POWER STORAGE APPARATUS AND ELECTRIC VEHICLE
BACKGROUND
[0001] The present disclosure relates to a power storage
apparatus as well as to an electric vehicle that utilizes
power from a power storage apparatus.
[0002] Recently, secondary batteries such as lithium-ion
batteries have been rapidly expanding to applications such
as storage batteries for automobiles and power storage
apparatus in which secondary batteries are combined with an
alternative energy system such as solar cells or wind
turbines. In the case of using a large number of storage
elements such as unit cells (also called electrical cells or
simply cells, and designated battery cells as appropriate in
the following description) in order to produce a large
output, a configuration is adopted in which a plurality of
storage modules are connected in series. A storage module
contains battery blocks in which a plurality of battery
cells (-four, for example) are connected in parallel and/or
in series. A large number of battery blocks are enclosed in
an outer case to form a storage module (also called an
assembled battery).
[0003] There also exists a battery system in which a
plurality of storage modules are connected, and in which a
control apparatus shared by the plurality of storage modules
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is provided. Each storage module includes a module
controller, with communication between the module
controllers and the control apparatus realized via a
communication unit or other means.
[0004] In the case of using a plurality of battery cells,
in some cases one of the plurality of battery cells will
reach the low-voltage threshold even though other battery
cells have not yet reached the low-voltage threshold, due to
factors such as differences in self-discharge among the
battery cells. If the battery cells are once again charged
in such a state, a problem occurs in that a battery cell may
not be sufficiently charged, and battery cell performance
may not be sufficiently exhibited.
[0005 ] In order to compensate for such disparities among
plural battery cells, battery cell balancing is typically
conducted. Controlling cell balancing involves acquiring
voltage information for a plurality of battery cells.
Japanese Unexamined Patent Application Publication No. 2010-
081756-.describes a configuration for acquiring battery
information from a battery cell.
SUMMARY
[0006] In the case of connecting a plurality of storage
modules in series, balancing of the modules is conducted.
Since differences in power expenditure by a control circuit
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connected to each storage module are a factor that can
disrupt module balance, it is preferable to not use power
from the battery pack of storage modules as the power for
the control circuits. Furthermore, since the voltage from a
serial connection becomes very high in the case of
connecting a plurality of storage modules in series,
isolation is desired for safety, and in addition, circuit
blocks able to operate at low voltages, such as a
communication unit and a controller, preferably operate
using a low-voltage power supply.
[0007] The configuration described in Japanese Unexamined
Patent Application Publication No. 2010-081756 above is for
acquiring battery information from single battery cells, and
does not make considerations for the acquisition of voltage
information from individual storage modules in the case of
outputting a high voltage, such as in the case where a
plurality of storage modules are connected in series.
[0006] Consequently, it is desirable to provide a power
storage apparatus and an electric vehicle suitable for
acquiring voltage information from individual storage
modules in the case where a plurality of storage modules are
connected in series.
[0009 ] Disclosed herein is a power storage apparatus that
includes a plurality of battery units each including a
single battery cell, a plurality of battery cells, or a
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plurality of battery blocks, a monitor configured to acquire
the respective voltages of the batteries in the battery
units, a communication unit configured to transmit
information on the voltages from the monitor to a managing
unit configured to manage the battery units, and an
isolating transmission unit, disposed in an isolating state
between the monitor and the communication unit, and
configured to communicate the voltage information while also
supplying the monitor with power and monitor control
information from the communication unit.
[0010 ] Also disclosed herein is a power storage apparatus
that includes a plurality of battery units each including a
single battery cell, a plurality of battery cells, or a
plurality of battery blocks, a monitor configured to acquire
the respective voltages of the batteries in the battery
units, a communication unit configured to transmit
information on the voltages from the monitor to a managing
unit configured to manage the battery units, and an
isolating transmission unit, connected in an isolating state
to the output side of the communication unit, and configured
to communicate the voltage information while also supplying
the communication unit with power from the managing unit.
[0011 ] Also disclosed herein is an electric vehicle that
includes a conversion apparatus configured to receive power
supplied from a power storage apparatus and convert received
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power into drive for the vehicle, and a control apparatus
configured to perform information processing related to
vehicle control on the basis of information regarding the
power storage apparatus. The power storage apparatus
includes a plurality of battery units each including a
single battery cell, a plurality of battery cells, or a
plurality of battery blocks, a monitor configured to acquire
the respective voltages of the batteries in the battery
units, a communication unit configured to transmit
information on the voltages from the monitor to a managing
unit configured to manage the battery units, and an
isolating transmission unit, disposed in an isolating state
between the monitor and the communication unit, and
configured to communicate the voltage information while also
supplying the monitor with power and monitor control
information from the communication unit.
[0012] In an embodiment, a power storage apparatus
includes a battery block comprising a plurality of battery
cells and an isolating unit that enables wireless
information transfer regarding battery information of the
battery block. In this embodiment, the isolating unit may
include a first card unit and a second card unit being
configured for a contactless smart card protocol to
facilitate the wireless information transfer, the first and
second card units configured to transmit the battery
information wirelessly to each other. Additionally, the
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isolating unit can include a first antenna mounted on a
first trace layer of a printed circuit board and
electrically connected to the first card unit and a second
antenna mounted on a second trace layer of the printed
circuit board and electrically connected to the second card
unit, the second antenna being directionally aligned with
the first antenna to enable the wireless information
transfer of battery information between the first and second
antennas.
[0013] In another embodiment, a power storage system
includes a first storage module including a first battery
block comprising a first plurality of battery cells and a
first isolating unit that enables wireless information
transfer regarding battery information of the first battery
block. In this other embodiment, the, power storage system
also includes a second storage module including a second
battery block comprising a second plurality of battery cells
and a second isolating unit that enables wireless
information transfer regarding battery information of the
second battery block. Additionally, in this embodiment,
battery information of the first storage module is
aggregated with battery information from the second storage
module.
[0014] In yet another embodiment, a power storage control
apparatus includes a battery block comprising a plurality of
battery cells, a controller configured to measure battery
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information of the battery block, and an isolating unit that
enables wireless communication with the controller and
wirelessly transmits power to the controller.
[0015] In a further embodiment, a power storage apparatus
to power a vehicle includes a plurality of storage modules,
each storage module including at least one battery block
comprising a plurality of battery cells a controller
configured to measure battery information of the at least
one battery block, and an isolating unit that enables
wireless communication with the controller and wirelessly
transmits power to the controller. In this embodiment, the
power storage apparatus to power the vehicle also includes
an electrical load including an electronic transmission or a
motor of a vehicle, the electrical load receiving power from
an aggregate of power from the plurality of storage modules.
[0016] In a module balancing circuit of the disclosure,
flyback transformers in each module are constructed
separately, thus enabling simplified wiring without wiring
in a star pattern, unlike configurations that share a
magnetic core. In the disclosure, the primary switches and
the secondary switches of the flyback transformers can be
controlled by independent control pulse signals.
Consequently, it becomes possible totransmit power via a
desired plurality of flyback transformers. Furthermore, by
setting the length of the on-periods during switching
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operation, the amounts of power to move via the flyback
transformers can be individually controlled. In other words,
the amount of power to move can be varied by lengthening the
period during which a switch is switched on in accordance
with the amount of power to move.
BRIEF DESCRIPTION OF THE DRAWINGS
[0017] Fig. 1 is a block diagram of an exemplary storage
system;
[0018] Fig. 2 is an exploded perspective view of an
exemplary storage module;
[0019 ] Fig. 3 is a wiring diagram illustrating the wiring
configuration of an exemplary storage module;
[0020 ] Fig. 4 is a block diagram illustrating a specific
configuration of a storage system;
[0021] Fig. 5 is a block diagram of an exemplary module
controller;
[0022 ] Fig. 6 is a block diagram illustrating a first
example of a configuration of a storage system connecting a
plurality of storage modules;
[0023 ] Fig. 7 is a schematic diagram illustrating how
components are packaged on a multilayer circuit board for a
storage module;
[0024] Fig. 8 is a wiring diagram illustrating the
circuit layout of an exemplary isolator;
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[0025 ] Figs. 9A and 9B are cross-section diagrams for
explaining a two-layer circuit board and a four-layer
circuit board;
[0026] Figs. 10A and 10B are schematic diagrams for
explaining specific examples of a PCB antenna;
[0027] Figs. 11A to 11C are schematic diagrams for
explaining bottom balancing;
[0020 ] Figs. 12A to 12C are schematic diagrams for
explaining active bottom cell balancing operation;
[0029 ] Figs. 13A to 13C are schematic diagrams for
explaining top balancing;
[0030 ] Figs. 14A to 14C are schematic diagrams for
explaining active top cell balancing operation;
[0031 ] Figs. 15A and 15C are wiring diagrams of an active
bottom cell balancing circuit of the related art;
[0032 ] Figs. 16A to 16D are timing charts for explaining
operation of an active bottom cell balancing circuit of the
related art;
[0033 ] Figs. 17A and 17B are wiring diagrams of an active
top cell balancing circuit of the related art;
[0034] Figs. 18A to 18D are timing charts for explaining
operation of an active top cell balancing circuit of the
related art;
[0035] Fig. 19 is a wiring diagram of an exemplary module
balancing circuit of the related art;
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[0036 ] Fig. 20 is a wiring diagram of an exemplary module
balancing circuit;
[003°7 ] Fig. 21 is a wiring diagram of a first exemplary
module balancing circuit of the present disclosure;
[0038] Fig. 22 is a wiring diagram illustrating a
specific example of a switch;
[0039] Fig. 23 is a wiring diagram for explaining
operation of a first exemplary module balancing circuit of
the present disclosure;
[0040 ] Figs. 24A to 24H are timing charts for explaining
operation of a first exemplary module balancing circuit of
the present disclosure;
[0041 ] Fig. 25 is a wiring diagram of a second exemplary
module balancing circuit of the present disclosure;
[0042 ] Fig. 26 is a wiring diagram of a third exemplary
module balancing circuit of the present disclosure;
[0043] Fig. 27 is a wiring diagram of a fourth exemplary
module balancing circuit of the present disclosure;
[0044] Fig. 28 is a block diagram of a first exemplary
storage system including a module balancing circuit of the
present disclosure;
[0045 ] Fig. 29 is a block diagram illustrating a second
example of a configuration of a storage system connecting a
plurality of storage modules;
[0046 ] Fig. 30 is a wiring diagram illustrating the
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circuit layout of another exemplary isolator;
[0047] Fig. 31 is a block diagram of a second exemplary
storage system including a module balancing circuit of the
present disclosure;
[0048 ] Fig. 32 is a wiring diagram for the case of
applying the present disclosure to a cell balancing circuit;
[0049] Fig. 33 is a block diagram of a first exemplary
application of a storage system including a module balancing
circuit of the present disclosure; and
[0050 ] Fig. 34 is a block diagram of a second exemplary
application of a storage system including a module balancing
circuit of the present disclosure.
DETAILED DESCRIPTION OF EMBODIMENTS
[0051] The embodiments described hereinafter are
preferred, specific examples of the disclosed technology,
and although various technically preferable limitations are
imposed, the scope of the disclosed technology is not to be
limited to these embodiments unless specifically limiting
statements are given in the following description.
Storage system
[ 0052] In the case of using a large number of storage
elements such as battery cells in order to produce a large
output, a configuration is adopted in which a plurality of
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storage units (hereinafter designated storage modules) are
connected, and in which a control apparatus shared by the
plurality of storage modules is provided. Such a
configuration is designated storage system.
[0053] A storage module is a unit combining a plurality
of battery cells and a controller. As illustrated in Fig. 1,
N storage modules MOD1 to MODN are connected in series. The
storage modules MODl to MODN are connected to an interface
bus BS via an isolator IS.
[0054 ] Additionally, monitors (hereinafter designated
module controllers as appropriate) are connected to an
overall control apparatus ICNT (hereinafter designated
control box as appropriate). The control box ICNT manages
charging, discharging, and wear suppression. The control
box ICNT may be realized by a microcontroller.
[0055 ] A serial interface is used as the bus inside the
storage modules and as the bus BS that connects the storage
modules M0D1 to MODN with the control box ICNT. For the
specific serial interface, an SM bus (System Management Bus),
CAN (Controller Area Network), or SPI (Serial Peripheral
Interface) may be used. For example, an 12C bus may be used.
On an I2C bus, synchronous serial communication is conducted
on two signal lines, SCL (serial clock) and a bidirectional
SDA (serial data).
[0056 ] The module controller CNT of each storage module
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MOD communicates with the control box ICNT. Namely, the
control box ICNT receives information on the internal state
of each storage module, or in other words battery
information, with charging and discharging processes being
managed for each storage module. The control box ICNT
supplies the output of the N serially-connected storage
modules (N x 51.2 V) to a load. In the example where N = 14,
the output becomes 14 x 51.2 V = 716.8 V.
Exemplary storage module
[0057] Fig. 2 is a perspective view illustrating a
mechanical configuration of a storage module MOD. The outer
case of the storage module MOD includes a metallic outer
case bottom 2a and outer case top 2b made from processed
sheet metal. It is preferable to use a material having high
terminal conductivity and emissivity as the material for the
outer case bottom 2a and outer case top 2b, as excellent
case heat dissipation can be obtained and temperature rises
inside the case can be suppressed. For example, the
material for the outer case bottom 2a and the outer case top
2b may be aluminum, an aluminum alloy, copper, or a copper
alloy. On the back of the case are provided an external
positive terminal 3 and an external negative terminal 4 for
charging and discharging the storage module MOD.
[0058] A current breaker 5 is additionally provided on
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the back of the storage module MOD. By providing the
current breaker 5, safety can be improved. Additionally, a
connector 6 for communication with a control circuit
disposed inside the case 2 is provided. The control circuit
is provided in order to monitor the temperature of the
battery unit and control charging, discharging, etc.
Additionally, one or more LEDs or other display elements
indicating the operational state are provided on the front
of the case.
[0059 ] The outer case bottom 2a of the case has a boxlike
structure, with the outer case top 2b being provided so
as to cover the opening. Sub-modules ASl to AS4 are stored
inside the storage space of the outer case bottom 2a. Since
the sub-modules AS1 to AS4 are secured by being screwed in
place, for example, a plurality of bosses are formed on the
floor of the outer case bottom 2a. The sub-modules ASl to
AS4 are pre-assembled outside of the case.
[0060] Each sub-module is an integrated combination of a
plurality of battery blocks by an insulating case that acts
as a secondary storage case. For the sub-module case, a
plastic or other molded component may be used. In the submodules
ASl to AS4, the plurality of battery blocks are
stored inside cases such that the internal positive and
negative terminals of the battery blocks are not exposed.
[0061] In a single battery block, eight cylindrical
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lithium-ion secondary batteries are connected in parallel,
for example. The sub-modules AS1 and AS2 are integrated
combinations of six battery blocks each by a case top and a
case bottom. The sub-modules AS3 and AS4 are integrated
combinations of two battery blocks each by a case top and a
case bottom. Consequently, a total of 6+6+2+2=16 battery
blocks are used. These battery blocks are connected in
series, for example.
[0062] In order to connect the battery blocks in series
in each of the sub-modules ASl to AS4, a connecting metal
plate such as a bus bar is used. A bus bar is a long, thin
bar of metal. A plurality of holes are formed on the bus
bar for connecting with connecting metal plates, etc.
leading out from the battery blocks.
[0063] As illustrated in Fig. 3, battery blocks Bl to B16
are connected in series, with each having eight batteries
connected in parallel. The battery blocks BI to B16 are
connected to the module controller CNT that acts as the
control apparatus for each storage module, with charging and
discharging being controlled. Charging and discharging is
done via the external positive terminal 3 and the external
negative terminal 4. For example, the battery blocks BI to
B6 may be included in the sub-module AS1, and the battery
blocks B11 to B16 may be included in the sub-module AS2.
Additionally, the battery blocks B7 and B10 may be included
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in the sub-module AS3, and the battery blocks B8 and B9 may
be included in the sub-module AS4.
[0064 ] Information on the voltage between the positive
and negative electrodes of each battery block, etc. is
supplied to the module controller CNT via a bus 10. The
module controller CNT monitors the voltage, current, and
temperature of each battery block, and outputs the
monitoring results as battery information. For example, a
single storage module MOD may output 16 x 3.2 V = 51.2 V.
[0065] Fig. 4 illustrates a more specific connection
configuration of a storage system. For example, four
storage modules MOD1 to MOD4 may be connected in series. In
this case, the total voltage retrieved from the positive
terminal 3 (VB+) and the negative terminal 4 (VB-) is
approximately 200 V. The storage modules include module
controllers CNT1 to CNT4 and battery block groups BB1 to BB4,
respectively. In each battery block group, 16 battery
blocks are connected in series, for example.
[0066] The module controllers CNT1 to CNT4 are connected
via a bus, with the communication terminal of the module
controller CNT4 connected to the control box ICNT.
Information on the per-module voltage, etc. from each module
controller is transmitted to the control box ICNT. The
control box ICNT additionally includes a communication
terminal 11 enabling external communication.
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Exemplary module controller
[0067 ] An exemplary configuration of a module controller
will be described with reference to Fig. 5. The module
controller CNT is configured to detect the voltage between
the terminals of n battery blocks B1 to Bn connected in
series, as well as the voltage of each battery block.
Provided is a multiplexer 15 that successively outputs the
voltage between the terminals of the battery blocks Si to Bn
and the voltage of each battery block.
[0060] The multiplexer 15 switches channels according to
a given control signal and selects one set of analog voltage
data from among n sets of analog voltage data. A set of
analog voltage data selected by the multiplexer 15 is
supplied to an A/D converter 16 (labeled an ADC, or Analog
to Digital Converter, in Fig. 5).
[ 0069] The A/D converter 16 converts analog volta<7e data
supplied from the multiplexer 15 into digital voltage data.
For example, analog voltage data may be converted into 14-
bit to 18-bit digital voltage data. Herein, various
techniques such as successive approximation or delta-sigma
may be used as the conversion technique in the A/D converter
16.
[ 0070 ] Digital voltage data from the A/D converter 16 is
supplied to a communication unit 17. The communication unit
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17 is controlled by a controller 18, and communicates with
external apparatus connected via communication terminals 19a
and 19b. For example, communication with the module
controller of another module may be conducted via the
communication terminal 19a, while communication with the
control box ICNT may be conducted via the communication
terminal 19b. Additionally, the module controller CNT
receives a control signal from the control box ICNT via the
communication terminal 19b. In this way, the communication
unit 17 communicates bidirectionally.
[0071] Additionally, it is configured such that the
controller 18 controls voltage leveling across battery
blocks. Such control is designated cell balancing. For
example, in the case where one battery block from among the
plurality of battery blocks B1 to Bn has reached the lowvoltage
threshold, other battery blocks still having
remaining charge may exist. At the next charging, the other
battery blocks with remaining charge may quickly reach the
high-voltage threshold, and charging to full charge may be
difficult. In order to avoid such imbalances, battery
blocks with remaining charge are forcibly made to discharge
by switching on a MOSFET (Metal-Oxide-Semiconductor Field-
Effect Transistor). However, the cell balancing technique
is not limited to the passive technique discussed above, and
what are called active techniques and various other
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techniques may be applied. Module balancing in this
disclosure will be described in detail later.
[ 0072] Meanwhile , the module controller CNT discussed
earlier monitors the voltage of each battery block, converts
the detected voltages into digital signals, and transmits
the digital signals to the control box ICNT. In addition to
voltage, the temperature of each battery block may also be
detected, with the temperatures converted into digital data
and transmitted to the control box ICNT.
[0073] Power for the module controller CNT is supplied
from the battery blocks Bl to Bn, as illustrated in Fig. S.
However, if the battery blocks B1 to Bn are used as the
power supply, disparities in the capacity of the battery
blocks Bl to Bn may occur among modules since the amounts of
power consumed by the module controllers CNT are not equal
to each other, and module imbalances may occur. Given this
factor, it is preferable to not use the battery blocks B1 to
Bn as the power supply for the module controller CNT.
[0074 ] In the module controller CNT illustrated in Fig. 5,
the A/D converter 16, the communication unit 17, and the
controller 18 enclosed by the inner broken lines constitute
a low-voltage power unit able to operate on a 5 V power
supply, for example. In this disclosure, it is configured
such that power to the low-voltage power unit is supplied
from the control box ICNT. If power is supplied from the
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battery blocks Bl Lo Bn, there is a risk of disrupting the
module balance due to different amounts of power consumed by
the module controllers CNT. In this disclosure, since power
to the low-voltage power units of the module controllers CNT
is supplied from the control box ICNT, such a problem may
not occur.
First example of storage system according to the disclosure
[0075] Fig. 6 illustrates a first example of a
configuration in which the present disclosure has been
applied to a storage system having n storage modules MOD1 to
MODn. The storage modules include communication units COM1
to COMn, isolators ISCl to ISCn, module controllers CNTl to
CNTn, and battery block groups BB1 to BBn, respectively.
The n storage modules are connected to a control box ICNT.
For connection, communication lines Li and L2 and a power
supply line Lp are used. Bidirectional communication
between the control box ICNT and the storage modules MOD1 to
MODn is done via the communication lines Ll and L2. CAN is
used as the communication protocol, for example. Recently,
CAN is being used for in-vehicle LAN.
[0076 ] The respective communication units COM1 to COMn in
the storage modules correspond to the. communication unit 17
in Fig. 5. Consequently, the module controllers CNT1 to
CNTn in Fig. 6 are configured to not include the
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communication unit 17 compared to the configuration in Fig.
5. However, both the communication units COM1 to COMn and
the communication unit 17 may also be provided and
configured to have respectively different functions. A
power supply voltage such as +5 V is supplied via the power
supply line Lp as power for the low-voltage power unit in
each storage module.
[0077] The isolators ISC1 to ISCn function to isolate the
communication units COM1 to COMn and the module controllers
CNT1 to CNTn from each other. In other words, the reference
potential of the power supply for the communication units
COM1 to COMn and the reference potential of the power supply
for the module controllers CNT1 to CNTn are split and made
to be independent. Additionally, the isolators ISCl to ISCn
function to supply power supply voltage to the module
controllers CNT1 to CNTn and function as a bidirectional
communication transmission medium while in an isolated state.
[0078] As an example, take the power supply voltage for
the control box ICNT and the communication units COM1 to
COMn to be 0 V to +5 V. Take the power supply voltage for
the module controller CNT1 of the storage module MOD1 to be
0 V to +5 V, the power supply voltage for the module
controller CNT2 of the storage module MOD2 to be +50 V to
+55 V, and the power supply voltage for the module
controller CNTn of the storage module MODn to be (+50 x n) V
I
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to (+50 x n) +5 V.
Isolators
[0079] The CAN standard may be used as the protocol for
bidirectional communication conducted via the isolators ISC1
to ISCn. Electromagnetic induction, magnetic resonance, or
electromagnetic radiation techniques may be used as the
technique for power transmission conducted via the isolators
ISCl to ISCn.
[0080] In this disclosure, contactless smart card
technology is used. With contactless smart card technology,
the antenna coil of a reader/writer is made to magnetically
couple with the antenna coil of a card to conduct
communication and power transmission between the
reader/writer and card. Communication, utilizes a technique
of applying ASK (Amplitude Shift Keying) modulation to a
carrier wave at a frequency of 13.56 kHz, and is conducted
at a speed of 212 kbps or 424 kbps. The isolators ISC1 to
ISCn are made to specifications similar to the above
contactless smart card protocol. Additionally, the
isolators ISCl to ISCn are configured to conduct
communication and power transmission between antennas
(coils) formed on different layers of a multilayer printed
circuit board.
[0081] As illustrated in Fig. 7, a microprocessor unit
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(MPU) constituting the control box ICNT and a reader/writer
chip 22 for the contactless smart card protocol are mounted
on a multilayer PCB 21. In addition, PCB antennas 23 and 24,
a card chip 25 for the contactless smart card protocol, and
the module controller CNT are mounted on the multilayer PCB
21.
[0062] As schematically illustrated in Fig. 8, with the
contactless smart card protocol, a transmit signal is formed
from the antenna 23 of a reader/writer unit 26 to a card
unit 27 with a carrier wave amplitude from 2 Vop to 13 Vop
and an approximately 10% degree of modulation, for example.
The transmit signal is transmitted from the antenna 23 to
the antenna 24 of the card unit 27. At the antenna 24, the
received signal is a high-frequency signal with a carrier
wave amplitude from 2 Vop to 13 Vop and, an approximately 10%
degree of modulation, for example. Power is formed at the
card unit 27 by smoothing the received signal. The power
consumption of the card unit 27 is significantly low.
[ 0063 ] An exemplary PCB antenna will now be described.
As illustrated in Fig. 9A, a four-layer PCB having four
trace layers LY1 to LY4 may be used as the multilayer PCB 21
on which antennas are formed as conductive patterns.
Alternatively, as illustrated in Fig. 9B, a two-layer PUB
having two trace layers LY11 and LY12 may be used.
[0064 ] As illustrated in Fig. 10A, the primary
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(reader/writer) antenna 23 is formed with a coil pattern 31a,
a linear pattern 31b, and a linear pattern 31c. The coil
pattern 31a is formed on the fourth trace layer LY4 of the
four-layer PCB, with the end at the center of the pattern
31a connected via a land and a through-hole to a land 32a on
the third trace layer LY3. The linear pattern 31b is formed
between the land 32a and the land 32b. The land 32b is
connected to the linear pattern 31c via a through-hole and a
land on the third trace layer LY3. The ends of the patterns
31a and 31c are connected to connectors not illustrated.
[0085] As illustrated in Fig. 10B, the secondary (card)
antenna 24 is formed with a coil pattern 41a, a linear
pattern 41b, a linear pattern 41c, and a linear pattern 41d.
The coil pattern 41a, one end of which is connected to a
connector (not illustrated), is formed oh the first trace
layer LY1 of the four-layer PCB. The land 42a is connected
to the linear pattern 41b via a through-hole and a 1mnd on
the second trace layer LY2. One end of the pattern 41b is
connected to a land on the first trace layer LY1 via a land
42b and a through-hole. One end of the linear pattern 41c
is connected to a land on the first trace layer LY1. The
other end of the linear pattern 41c is connected to a
connector (not illustrated). Additionally, one end of the
linear pattern 41d is connected to a land 42c which is
connected to the coil pattern 41a. The other end of the
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linear pattern 41d is connected to a reference potential
point.
[0086] In cases where patterns intersect, the PCB
antennas are realized by different trace layer patterns.
Through--holes and lands are used to connect different trace
layers. As a result, extra lands 32c and 32d are produced
on the fourth trace layer as illustrated in Fig. 1OA, and an
extra land 42d is produced on the first trace layer.
[0067 ] It may also be configured such that jumper lines
are used instead of forming the above-described patterns on
other trace layers of the PCB. In other words, jumper lines
may be used instead of the pattern 31b in Fig. 10A as well
as the patterns 41b and 41d in Fig. lOB. In this case, a
two-layer PCB may be used, through-holes may be omitted, and
the production of extra lands can be avoided. By not
forming through-holes, it becomes possible to further
increase the dielectric strength of the PCB.
[0088] The isolators in this disclosure provide
insulation between the primary antenna and the secondary
antenna by means of the PCB. Consequently, with the
isolators in this disclosure a DC insulation voltage of 1000
V or more becomes possible. This furthermore has the merit
of enabling bidirectional communication and power
transmission, while reducing costs.
- 25 -
SP327450
Cell balancing
[0089] In this disclosure, the voltage balance among the
above-described plurality of storage modules MOD1 to MODn
(hereinafter simply designated the module balance) is
controlled. In other words, the output voltages of the
storage modules are leveled by module balancing. Since each
storage module includes many battery cells, disparities
among modules are ordinarily greater than the voltage
balance among battery cells inside the storage modules
(hereinafter simply designated the cell balance).
Consequently, it is worthwhile to balance modules even if
the cells within the storage modules are also being balanced.
[0090 ] Before describing the present disclosure, typical
cell balancing will be described. As illustrated in Figs.
11A to 11C, the cell balance among three battery cells BT1,
BT2, and BT3 will be investigated. First, assume that all
battery cells are fully charged, as illustrated in Fig. 11A.
Next, assume that the battery cells have discharged and
disparities in the discharge amounts have occurred, and that
the voltage of the battery cell BT1 has reached the lowvoltage
threshold indicated by the broken line, as
illustrated in Fig. 11B. Due to the disparities among the
battery cells, the other battery cells BT2 and BT3 have not
yet reached the low-voltage threshold. Differences in selfdischarge
rates may be the cause of the disparities in the
- 26 -
SP327450
discharge amounts among the battery cells, for example.
[0091] If charging commences in this state, the battery
cell BT2, which had the most charge remaining at the time
the voltage of the battery cell BT1 reached the low-voltage
threshold, may reach full charge first. At this point, the
battery cell BT1 may not have been charged to full charge,
as illustrated in Fig. 11C. Consequently, the amount that
can be discharged from a full charge may decrease from the
discharge amount Cl to the discharge amount C2.
[0092] In order to solve this problem, as illustrated in
Figs. 12A and 12B, the remaining charges are nearly
equalized by transferring power from the battery cell BT2,
which had the most charge remaining (highest potential) at
the time the battery cell BT1 reached the low-voltage
threshold, to the battery cell BT1, which had the least
charge (lowest potential). By subsequently charging the
battery cells BT1, BT2, and BT3, the three battery cells can
be charged to nearly the full charge voltage. In practice,
the process is repeated multiple times.
[0093] Such control is designated active bottom cell
balancing. With bottom cell balancing, decreases in the
dischargeable amount can be prevented. Passive bottom cell
balancing designates a technique in which, given the state
illustrated in Fig. 12A, the battery cells BT2 and BT3 are
discharged to match the potential of the battery cell BT1
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SP327450
with the lowest potential. Compared to passive techniques,
active techniques can utilize charge more effectively and
are thus preferable.
[0094] Active balancing will not be described with
reference to Figs. l3A to 13C and l4A to 14C. First, assume
that all battery cells have been fully charged, as
illustrated in Fig. 13A. Next, assume that the battery
cells are discharged, as illustrated in Fig. 13B.
[0095 ] If charging subsequently commences, the voltage of
the battery cell BT2 reaches the high-voltage threshold
first, as illustrated in Fig. 13C. At this point, the
voltages of the battery cells BTl and BT3 have not reached
the high-voltage threshold. Consequently, the charged
amount decreases as indicated by C12 with respect to the
charged amount Cll (Fig. 13A).
[0096] In order to solve this problem, as illustrated in
Figs. 14A and 14B, the remaining charges are nearly
equalized by transferring power from the battery cell BT2,
which had the most charge (highest potential) at the time
the battery cell BT2 reached the high-voltage threshold, to
the battery cell BTl, which had the least charge (lowest
potential). By subsequently charging the battery cells BTl,
BT2, and BT3, the three battery cells, can be charged to
nearly the full charge voltage. In practice, the process is
repeated multiple times.
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SP327450
[0097 ] Such control is designated active top cell
balancing. With top cell balancing, decreases in the
chargeable amount can be prevented. Passive top cell
balancing designates a technique in which, given the state
illustrated in Fig. 14A, the battery cells BT2 and BT3 are
discharged to match the potential of the battery cell BT1
with the lowest potential. Compared to passive techniques,
active techniques can utilize charge more effectively and
are thus preferable.
Cell balancing circuit of the related art
[0098] An exemplary active bottom cell balancing circuit
of the related art that uses a flyback transformer will now
be described with reference to Figs. l5A to 15B and 16A to
16D. The cathode and anode of each battery cell are
respectively connected to both ends of primary coils Wl to
W6. The cathode and anode of six battery cells BT1 to BT6
connected in series are connected to both ends of a
secondary coil WO. Additionally, a common magnetic core M
is provided. Additionally, the secondary coil WO is
connected in series to a secondary switch SO, and the
primary coils W1 to W6 are respectively connected in series
to primary switches Si to S6. The switches SO to S6 are
realized with MOSFETs (Metal-Oxide-Semiconductor Field-
Effect Transistor), for example.
- 29 -
SP327450
[0099 ] Figs. 16A to 16D are timing charts for operation
of the active bottom cell balancing circuit illustrated in
Figs. l5A and 15B. As an example, the respective voltages
of the battery cells BT1 to BT6 are detected by a monitor
not illustrated, and the voltage of the battery cell BT2 is
the lowest. In this case, power is moved to the battery
cell BT2 from the other battery cells. First, the switch SO
is switched on as illustrated in Figs. 15A and 16A, and a
current Il as illustrated in Fig. 16C flows in the coil WO,
magnetizing the magnetic core M.
[0100] Next, the primary switch S2 connected in series to
the coil W2 is switched on as illustrated in Figs. 15B and
16B, while in addition, the secondary switch SO is switched
off, as illustrated in Fig. 16A. Electromagnetic energy in
the magnetic core M is released and a current 12 flows
through the primary coil W2, as illustrated in Fig. 16D.
This current 12 flows into the battery cell BT2, charging
the battery cell BT2.
[0101 ] After that, the primary switch S2 is switched off,
as illustrated in Fig. 16B. Additionally, a pause is
subsequently held for a given amount of time. Operation is
repeated, with the above on-period of the secondary switch
SO, the on-period of the primary switch S2, and the pause
period making up the cycle period.
[0102 ] An exemplary active top cell balancing circuit of
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SP327450
the related art will now be described with reference to Figs.
17A to 17B and 18A to 18D. The cathode and anode of each
battery cell are respectively connected to both ends of
primary coils Wl to W6. The cathode and anode of six
battery cells BT1 to BT6 connected in series are connected
to both ends of a secondary coil WO. Additionally, a common
magnetic core M is provided. Additionally, the secondary
coil WO is connected in series to a secondary switch SO, and
the primary coils W1 to W6 are respectively connected in
series to primary switches Sl to S6. The switches SO to S6
are realized with MOSFETs, for example.
[0103] Figs . 18A to 18D are timing charts for operation
of the active top cell balancing circuit illustrated in Figs.
17A and 176. As an example, the respective voltages of the
battery cells BT1 to BT6 are detected by a monitor not
illustrated, and the voltage of the battery cell BT5 is the
highest. In this case, power is moved to the battery cell
BT5 from the other battery cells. First, the switch S5 is
switched on as illustrated in Figs. 17A and 18B, and a
current Ii flows through the coil W5 as illustrated in Fig.
18D, magnetizing the magnetic core M.
[0109] Next, the secondary switch SO is switched on as
illustrated in Figs. 17B and 18A, while in addition, the
primary switch S5 is switched off, as illustrated in Fig.
18B. Due to the electromagnetic energy in the magnetic core
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SP327450
M, a current 12 flows through the secondary coil WO, as
illustrated in Fig. 18C. This current 12 flows into the
battery cells BT1 to BT6 connected in series, and power is
distributed among the battery cells.
[0105 ] After that, the secondary switch SO is switched
off, as illustrated in Fig. 18A. Additionally, a pause is
subsequently held for a given amount of time. Operation is
repeated,Iwith the above on-period of the primary switch S5,
the on-period of the secondary switch SO, and the pause
period making up the cycle period.
Module balancing circuit
[0106 ] The balancing circuit of the related art discussed
above relates to battery cells, and problems occur when
applied to balance among the modules described with
reference to Figs. 1 to 6. Herein, module balance refers to
the voltage balance of battery units that include a
plurality of battery cells or battery blocks inside
respective storage modules. Ordinarily, imbalances among
modules take greater values versus imbalances within modules.
Although it is possible to resolve imbalances among modules
as a result of balancing each storage module, the process
takes more time. However, module balancing and the cell
balancing of the related art discussed above may also be
used in conjunction. As an example, in this case inter-
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Se327450
module balancing is conducted first and then intra-module
balancing is conducted,
[0107] Fig. 19 illustrates a configuration in which a
cell balancing circuit of the related art has been applied
as-is to an active module balancing circuit. Balancing is
conducted among 14 modules, for example. Battery block
groups BB1 to BB14 are connected in series. Each battery
block group is configured with eight battery cells connected
in parallel and with 16 parallel connections of eight
battery cells each (battery blocks) connected in series
(referred to as an 8P16S configuration). A single battery
block group produces a voltage of 3.2 V x 16 = 51.2 V.
Consequently, 14 battery block groups BBl to BB14 connected
in series produce a voltage of 51.2 V x 14 = 716.8 V.
[0108] The cathode and anode of the 14 battery block
groups connected in series are connected to both ends of a
secondary coil WO. Additionally, a common magnetic core M
is provided. A secondary switch SO is connected in series
to the secondary coil WO, and primary switches Si to S14 are
respectively connected in series to primary coils Wl to W14.
The switches SO to S14 are realized with MOSFETs, for
example.
[0109 ] Active bottom cell balancing operation with the
configuration in Fig. 19 involves switching on the switch SO,
magnetizing the magnetic core M due to the current that
- 33 -
SP327450
flows through the secondary coil NO. Next, the primary
switch is switched on for the storage module with the lowest
voltage, and the battery block group of the corresponding
storage module is charged by the electromagnetic energy
imparted to its primary coil. As an example, in the case
where the voltage of the battery block group BB2 is 32.0 V
and the voltage of the other battery block groups is 32.6 V,
after the secondary switch SO has been switched on for a
given amount of time, the switch SO is switched off while
the primary switch S2 of the battery block group BB2 is
switched on. The battery block group BB2 is charged by the
current that flows through the primary coil W2.
[0110] Active top cell balancing operation with the
configuration in Fig. 19 involves switching on the switch
connected to the primary coil of the battery block group
with the highest voltage. Next, that switch is switched off
while the switch SO is switched on. Current flows through
the secondary coil WO, and the battery block groups BB1 to
BB14 are charged. As an example, in the case where the
voltage-of the battery block group BB2 is 56.5 V and the
voltage of the. other battery block groups is 55.9 V, after
the primary switch S2 has been switched on for a given
amount of time, the switch S2 is switched off while the
secondary switch SO is switched on. The battery block
groups BB1 to BB14 are charged by the current that flows
- 34 -
SP327450
through the secondary coil WO.
[0111 ] Since the magnetic core M of the transformer is
shared in the configuration in Fig. 19, it is difficult to
configure it such that a plurality of storage modules, such
as 14, are stored in separate cases. In such cases, a
transformer apparatus is configured such that a transformer
unit including a magnetic core, a coil, and a switch is
stored in a separate case from the 14 storage modules, with
the 14 storage modules being connected in a star pattern
centered about the transformer apparatus. Such a star
pattern configuration is problematic in that the star
pattern wiring becomes complex if there are many storage
modules.
Problems with module balancing circuit of the related art
[0112 ] In the configuration in Fig. 19, a voltage of
716.8 V is applied to the series circuit of the secondary
coil WO and the switch SO by the 14 battery block groups
connected in series. When used in practice, a preferable
withstand voltage is taken to be approximately three times
the applied voltage. Thus, the withstand voltage becomes
2000 V for the FETs or other semiconductor switch element
constituting the switch SO. The configuration in Fig. 19,
which includes semiconductor switch elements with such
withstand voltages, is difficult to realize.
- 35 -
SP327450
[0113] As illustrated in Fig. 20, the magnetic core M may
be split into 14 magnetic cores Ml to M14, and the secondary
coil WO may be split into 14 secondary coils WOl to W014.
In so doing, the 14 storage modules can be split up and
stored in cases. In the configuration in Fig. 20, a voltage
of 716.8 V is respectively applied to the primary switches
S01 to S014. However, with the configuration in Fig. 20, it
is possible to construct flyback transformers separately and
respectively connect the primary and secondary switches to
the coils for independent control of switching operation.
Consequently, as discussed later, it becomes possible to
control the parallel retrieval of power from a plurality of
battery block groups as well as the parallel supply of power
to a plurality of battery block groups. Moreover, the
amount of power can be controlled by controlling the length
of the on-periods during switching operation.
Module balancing circuit according to disclosure
[0114 ] As illustrated in Fig. 21, in this disclosure, a
flyback transformer Tl includes a primary coil W1, a
secondary coil W01, and a magnetic core Ml. A switch Si is
connected in series to the primary coil W1, and a switch S01
is connected in series to the secondary coil W01. Flyback
transformers T2 to T14 similarly include primary coils W2 to
W14, secondary coils W02 to W014, and magnetic cores M2 to
- 36 -
SP327450
M14. Switches S2 to S14 are connected in series to the
primary coils W2 to W14. Switches S02 to 5014 are connected
in series to the secondary coils W02 to W14.
[0115] The series circuit of the primary coil Wl and the
switch Sl in the flyback transformer Ti is connected to the
positive and negative ends of a battery block group BB1 in a
storage module. The other respective series circuits of the
primary coils W2 to W14 and the switches S2 to S14 are
connected to the positive and negative ends of the battery
block groups BB2 to BB14 in storage modules.
[0116] A storage element 51 is provided, and a common
power supply voltage CV is produced by the storage element
51. The common power supply voltage CV is taken to be a
lower voltage than the total voltage 716.8 V of the battery
block groups connected in series, and is preferably set to a
voltage that is approximately 1/3 of the withstand voltage
of the secondary switches or less. For example, the common
power supply voltage CV may be set to a value approximately
equal to the unit voltage (51.2 V) of a battery block group.
By controlling the total discharging current and the total
charging current, the common power supply voltage CV is
controlled at a desired voltage without overvoltage or
undervoltage.
[0117] The storage element 51 is a battery, capacitor,
etc. Due to the storage element 51, one common power supply
- 37 -
SP327450
line CL+ is taken to be at the common power supply voltage
CV, while another common power supply line CL- is taken to
be a OV. The other common power supply line CL- is taken to
be a separate power supply not connected to the power supply
(V-) for the battery block groups of the plurality of
storage modules connected in series. However, the common
power supply line CL- may be connected to the power supply
V-. One end of each of the split secondary coils WOl to
W014 is connected to the common power supply line CL+, while
the other end of each of split secondary coils WO1 to W014
is connected to the common power supply line CL- via the
switches S01 to S014.
[0118] The switches Si to S14 as well as the switches S01
to S014 are realized with MOSFETs, for example. As
illustrated in Fig. 22, the switch SOl of the flyback
transformer T1 for example includes a MOSFET QO1 with a
diode DO1 connected between its drain and source, while the
switch Sl includes a MOSFET Q1 with a diode D1 connected
between its drain and source. Switching on and off is
controlled by a control signal from the controller of the
control box ICNT. The control box ICNT receives information
on voltage monitoring results from the module controller CNT
in each storage module, and generates -a control signal
(pulse signal). However, other semiconductor switch
elements besides MOSFETs may also be used, such as IGBTs
- 38 -
SP327450
(Insulated Gate Bipolar Transistors). However, with a
switch (including a MOSFET and a diode connected between its
drain and source), current automatically flows through the
diode in response to current flowing in the source-to-drain
direction, even without a control signal (automatic switchon).
[0119] The common power supply voltage CV is applied to
the series circuits of the secondary coils W01 to WO1.4 and
the switches SO1 to 5014. For example, by setting the
common power supply voltage CV to a voltage similar to the
voltage applied to the primary coils and switches (51.2 V),
the withstand voltage of the secondary switches S01 to S014
can be taken to be approximately 154 V. Such a withstand
voltage is not a particularly high value for the
semiconductor switch constituting the secondary switches S01
to S014, making it easier to construct a module balancing
circuit.
[0120] In each of the flyback transformers T1 to T14, the
turns ratio of primary coil versus secondary coil is not
limited to one, but the phase is taken to be inverted
between primary and secondary. Furthermore, the flyback
transformers T1 to T14 are able to bidirectionally transmit
power. Consequently, the labeling of "primary" and
"secondary" is for the sake of convenience, and it is
possible to transmit power both from primary to secondary as
- 39 -
SP327450
well as from secondary to primary.
[0121] Taking the flyback transformer Ti as an example,
if the switch Si is switched on from a state where the
switches Si and S01 are off, current flows through the coil
W1, magnetizing the magnetic core Ml. During the period in
which the switch Sl is on, a current that increases with
time flows through the coil W1. Next, if the switch Si is
switched off and the switch S01 is switched on, current
flows into the coil W01 via the switch SO1, since the
magnetic core is magnetized. This current is a current that
decreases with time. Operation of the other flyback
transformers is similar. The flyback transformers function
as coupled inductors.
[0122] Active bottom cell balancing operation with the
configuration in Fig. 21 involves controlling the primary
switches to move power from the battery block group with the
highest voltage to the storage element 51, and additionally
controlling the secondary switches to move power to the
battery block group of the storage module with the lowest
voltage.` In this way, a module balancing circuit according
to the disclosure moves power in two stages via
bidirectional flyback transformers.
[0123] As an example, operation will be described for the
case where the voltage of the battery block group BB3 is the
highest at 32.6 V, while the voltage of the battery block
- 40 -
SP327450
group BB2 is the lowest at 32.0 V. First, the switch S3 is
switched on, and current flows into the primary coil W3 of
the flyback transformer T3 with the battery block group BB3
acting as the power supply. Next, the switch S3 is switched
off and the switch S03 is switched on. Due to the
electromagnetic energy, current flows through the secondary
coil W03, charging the storage element 51.
[0124] Next, the switch S03 is switched off while the
switch S02 is switched on. Due to the storage element 51,
current flows through the secondary coil W02 of the flyback
transformer T2. Next, the switch S02 is switched off while
the switch S2 is switched on. The battery block group BB2
is charged by the current that flows through the primary
coil W2. In so doing, active bottom cell balancing
operation is achieved.
[0125 ] Active top cell balancing operation with the
configuration in Fig. 21 involves controlling the primary
switches to move power from the battery block group with the
highest voltage to the storage element 51, and additionally
controlling the secondary switches to move power to the
battery block group of the storage module with the lowest
voltage. In this way, a module balancing circuit according
to the disclosure moves power in two stages via
bidirectional flyback transformers.
[0126 ] As an example, operation will be described for the
- 41 -
SP327450
case where the voltage of the battery block group BB3 is the
highest at 56.5 V, while the voltage of the battery block
group BB2 is the lowest at 55.9 V. First, the switch S3 of
the flyback transformer T3 is switched on, and current flows
into the primary coil W3 with the battery block group BB3
acting as the power supply. Next, the switch S3 is switched
off and the switch S03 is switched on. Due to the
electromagnetic energy, current flows through the secondary
coil W03, and the storage element 51 is charged.
[0127 ] Next, the switch S03 is switched off while the
switch S02 of the flyback transformer T2 is switched on.
Due to the storage element 51, current flows through the
secondary coil W02. Next, the switch S02 is switched off
while the switch S2 is switched on. The battery block group
BB2 is charged by the current that flows through the primary
coil W2. In so doing, active top cell balancing operation
is achieved.
[0128] Active top cell balancing operation will now be
described in further detail with reference to Figs. 23 and
24A to 24H. As illustrated in Fig. 23, a current that flows
through the coil W3 of the flyback transformer T3 is labeled
il, while a current that flows through the coil W03 is
labeled i2. The currents i1 and i2 are in antiphase. A
current that flows through the coil W02 of the flyback
transformer T2 is labeled i3, while a current that flows
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5P327450
through the coil W2 is labeled i4. The currents i3 and i4
are in antiphase. Furthermore, assume that the storage
element 51 is fully charged when operation commences.
[0129] As illustrated in the timing chart in Fig. 24,
power transmission via the flyback transformer T3 and power
transmission via the flyback transformer T2 are conducted in
parallel. First, the switches S3 and S02 are switched on
for the same period, as illustrated in Figs. 24A and 24C.
Switching on the switch S3 causes a gradually increasing
current it to flow through the coil W3, as illustrated in
Fig. 24E. Switching on the switch S02 causes a gradually
increasing current i3 to flow through the coil W02, as
illustrated in Fig. 24G. The current i3 flows in a
discharge direction to the storage element 51.
[0130] Next, the switches S3 and S02 are switched off,
and the switches S03 and S2 are switched on for the same
period, as illustrated in Figs. 24B and 24D. Switching on
the switch S03 causes a gradually decreasing current i2 to
flow through the coil W03, as illustrated in Fig. 24F. The
current i2 flows in a charging direction to the storage
element 51. Due to the charging of the storage element 51
by the current i2, power is moved from the battery block
group BB3 to the storage element 51.
[0131 ] Switching on the switch S2 causes a gradually
decreasing current i4 to flow through the coil W2, as
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SP327450
illustrated in Fig. 24H. The current i4 flows in a charging
direction to the battery block group BB2. Due to the
charging by the current i4, power in the storage element 51
is moved to the battery block group BB2. Note that in
actual power transmission, it is configured such that power
is moved a little bit at a time by multiple switching
operations rather than a single switching operation.
Furthermore, the amount of power to move can be set to a
desired amount by applying pulse-width modulation to a pulse
signal for a switch to control the switch's on-period. Also,
although the switches S3 and S02 are depicted in a
synchronized form in Figs. 24A and 24C, in practice an
asynchronous relationship may be acceptable by allowing a
given range in the common power supply voltage CV.
Modification of module balancing circuit according to
disclosure
[0132] In the above-described module balancing circuit
according to the disclosure, it is configured such that
power retrieved via a single flyback transformer is moved
via a single flyback transformer. However, power may also
be retrieved via a plurality of flyback transformers. For
example, it may be configured such that power is retrieved
from both the storage module with the largest voltage and
the storage module with the second-largest voltage.
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SP327450
Furthermore, it may also be configured such that retrieved
power is moved via a plurality of flyback transformers. For
example, it may be configured such that power is supplied to
both the storage module with the lowest voltage and the
storage module with the second-smallest voltage. For
example, with the configuration in Fig. 21 discussed above,
power may be retrieved with a small current via the flyback
transformer T14, while at the same time retrieving power
with a large current via the flyback transformer T3.
Additionally, it may be configured such that power is
respectively supplied with medium currents via the flyback
transformers Ti and T2, contemporaneously with the power
retrieval,
[0133 ] As illustrated in Fig. 25, capacitors Cl to C14
are inserted between the common power supply line CL+ and
the common power supply line CL- on the secondary side in
each of the flyback transformers Ti to T14 of the storage
modules. By reducing high-frequency components with the
capacitors C1 to C14, voltages produced on the common power
supply lines CL+ and CL- can be output as DC (Direct
Current) power. It may also be configured such that this DC
power is supplied as the power supply for the control box
ICNT.
[0134] Furthermore, as illustrated in Fig. 26, it may be
configured such that a common flyback transformer Tx is
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SP327450
provided for all storage modules. The flyback transformer
Tx includes a primary coil Wy, a secondary coil Wx, and a
magnetic core Tx. The coil Wx is connected in series to a
switch Sx. The coil Wy is connected in series to a switch
Sy. One end of the secondary coil Wx in the flyback
transformer Tx is connected to a terminal 52, while the
other end is connected to a OV line via the switch Sx. The
terminal 52 is connected to the common power supply voltage
CV terminal.
[0135] One end of the primary coil Wy is connected to the
cathode (V+) of a series connection of battery block groups
BB1 to BB14 in a plurality of storage modules, such as 14.
The other end of the primary coil Wy is connected to the
anode (V-) of the series connection of battery block groups
BB1 to BB14. Flyback transformers Tl to T14 and a storage
element 51 are connected to the battery block groups BB1 to
BB14 similarly to the configuration in Fig. 21, and module
balancing like that discussed earlier is conducted.
[0136] According to the configuration in Fig. 26, power
can be supplied to the battery block groups of all storage
modules at once via the flyback transformer Tx, enabling
increased variation in module balancing operation.
[0137] Furthermore, in this disclosure, it is possible to
use a power transmission apparatus based on an
electromagnetic coupling technique, such as a forward
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SP327450
converter or RCC (Ringing Choice Converter) technique, rather
than a flyback converter technique.
[0133] Fig. 27 illustrates an application of the
disclosure, in which the storage modules MODl to MOD14 (the
configuration illustrated in Fig. 21) are connected to
another storage system that includes storage modules MOD101
to MOD104. It is possible to connect the common power
supply lines CL+ and CL- to the other storage system if the
common power supply voltages CV have an equivalent
relationship between the two storage systems. In other
words, it is easy to increase the number of connected
storage modules.
[0139 ] Fig. 28 illustrates an exemplary overall
configuration of a storage system that includes storage
modules, such as storage modules MODI and MOD2. Control
pulses are supplied from pulse generators 53 to the primary
switches (MOSFETs) Sl and S2 of the flyback transformers T1
and T2 in the module balancing circuit discussed earlier.
The pulse generators 53 generate control pulses in response
to control signals from the module controllers CNTl and CNT2.
For example, the pulse generators 53 may output PWM control
pulses. Control pulses are supplied from MCUs
(Microcontroller Units) in communication units COM1 and COM2
to the secondary switches (MOSFETs) S01 and S02 of the
flyback transformers T1 and T2.
- 47 -
SP327450
[0140] The control box ICNT determines a module balancing
sequence from per-module voltage information. Any module
balancing charging or discharging is individually relayed to
the MCUs in the communication units COM1 and COM2 of the
respective modules. The MCUs respectively supply the
secondary side of the flyback transformers with control
signals directly, or transmit control signals to the primary
side of the flyback transformers by isolated communication
via isolators ISC.
[0141 ] Control signals are supplied from separate circuit
blocks for the primary and secondary sides because of
differences in the control signal levels. Also, in parallel
with the operation discussed earlier, the control box ICNT
measures the voltage between the power supply lines CL+ and
CL- supplying the common power supply voltage CV, and
applies overall module balancing control such that the
common power supply voltage CV becomes a desired voltage.
Advantages of power storage apparatus according to
disclosure
[0142] In a module balancing circuit of the disclosure,
the flyback transformers in each module are constructed
separately, thus enabling simplified wiring without wiring
in a star pattern, unlike configurations that share a
magnetic core.
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[0143 ] In a module balancing circuit of the disclosure,
the voltage at either end of a battery block group in each
storage module is applied to the primary coil and switch of
a flyback transformer, while a common power supply voltage
CV is applied to the secondary coil and switch. The common
power supply voltage CV is taken to be a value equivalent to
the voltage at either end of a battery block group in each
storage module, for example. Consequently, there is an
advantage in that the voltage of all storage modules
connected in series is not applied to the coils and switches,
and elements with low withstand voltages can be used for the
coils and switches.
[0144] In this disclosure, the primary switches S1 to S14
and the secondary switches S01 to S014 of the flyback
transformers can be controlled by independent control pulse
signals. Consequently, it becomes possible to transmit
power via a desired plurality of flyback transformers.
Furthermore, by setting the length of the on-periods during
switching operation, the amounts of power to move via the
flyback transformers can be individually controlled. In
other words, the amount of power to move can be varied by
lengthening the period during which a switch is switched on
in accordance with the amount of power to move.
[0145 ] Additionally, since a large current flows between
the output terminals V+ and V-° of the plurality of storage
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modules, a comparatively large amount of noise may be easily
produced. However, since the common power supply voltage CV
is isolated from the output terminals V+ and V-, the effects
of noise due to fluctuations in the load current can be
lessened.
[0146] A common power supply voltage CV with little
influence from noise can be used as the power supply for the
control box ICNT. For example, the value of the common
power supply voltage CV may be taken to be a value
equivalent to the power supply voltage of the controller
(such as +5 V or +12 V). When using the common power supply
voltage CV as the power supply for the control box ICNT, the
power supply for the control box ICNT can be made resilient
to voltage fluctuations in the storage modules.
Second example of storage system according to the disclosure
[0147] In the first example of a storage system discussed
above, isolators ISC1 to ISCn are disposed between the
communication units COM1 to COMn and the module controllers
CNT1 to'CNTn, as illustrated in Fig. 6. However, a second
example of a storage system is configured such that the
isolators ISM to ISCn are disposed between the
communication units COM1 to COMn and the control box ICNT,
as illustrated in Fig. 29. The isolators ISC1 to ISCn and
the control box ICNT are connected by communication lines Ll
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and L2, and by a power line Lp. An interface such as SPI or
CAN is used as the communication interface. Although
disposed inside the storage modules MOD1 to MODn in Fig. 29,
the isolators ISC1 to ISCn may also be disposed externally
to the modules.
[0148] Similarly to the first example discussed above,
the isolators ISCl to ISCn function to isolate the
communication units COMI to COMn and the control box ICNT
from each other, supply power supply voltage to the
communication units COM1 to COMn, and function as a
transmission medium for bidirectional communication. The
CAN standard, for example, may be used as the protocol for
bidirectional communication conducted via the isolators ISC1
to ISCn. Electromagnetic induction, magnetic resonance, or
electromagnetic radiation techniques may be used as the
technique for power transmission conducted via the isolators
ISC1 to ISCn.
[0149] Besides an isolator configuration that uses
contactiess smart card technology as in the first example
discussed above, a photocoupler configuration may also be
used, in which changes in light from a photodiode 61 are
converted to changes in voltage by a phototransistor 62, as
illustrated in Fig. 30A. The photocoupler is used for data
transmission. Additionally, a device that conducts wireless
communication based on short-range wireless technology may
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be used, the device including a transmitter device 71 and a
receiver device 72, as illustrated in Fig. 308.
Specifically, a technology such as Bluetooth (registered
trademark), USB, ZigBee, or NFC may be used. Wireless
technologies other than short-range wireless technology may
also be used.
[0150] Bluetooth (registered trademark) is a short-range
wireless technology with a maximum communication range of
100 meters, using the 2.4 GHz frequency band. UWB (Ultra-
Wideband) is able to use a very large bandwidth (3.1 GHz to
10.6 GHz) to communicate up to a maximum of 480 Mbps over a
distance of approximately 10 meters. ZigBee is a shortrange
wireless technology being standardized by the ZigBee
Alliance. ZigBee uses the 2.4 GHz, 902 to 928 MHz, and 868
to 870 MHz frequency bands, with a maximum communication
range from 9 to 69 meters. NFC (Near Field Communication)
is a short-range wireless technology in the 13.56 MHz band.
NFC standardizes the wireless interface portion of
contactless smart card technologies from multiple standards,
creating cross-compatibility among contactless smart cards.
NFC has been standardized in two stages, and two standards,
Type A and Type B, exist. Furthermore, a configuration
compatible with a plurality of communication protocols may
also be included.
[0151 ] In this disclosure, the isolators ISC1 to ISCn
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transmit power in addition to communicating data. In order
to transmit power, a wireless power transmission protocol
between a power transmitter device 73 and a power receiver
device 74 utilizing for example magnetic resonance is used,
as illustrated in Fig. 30C. A high-frequency signal from a
high-frequency power supply is supplied to the power
transmitter device 73 via a matching circuit. Connected to
the power receiver device 74 are a matching circuit and a
rectifier circuit.
[0152] Fig. 31 illustrates an exemplary overall
configuration of a second example of a storage system that
includes storage modules, such as storage modules MOD1 and
MOD2. Battery block groups BB1 and BB2 are respectively
connected to module balancing circuits. Each module
balancing circuit is supplied with a control signal from
module controllers CNTl and CNT2, and a control signal from
MCUs (Microcontroller Units) in the communication units COM1
and COM2. The module balancing circuits are controlled
similarly as in the configuration illustrated in Fig. 28.
[0153] A power supply line and a communication line from
the control box ICNT are respectively illustrated as single
lines. A connection between the control box ICNT and the
communication units COMI and COM2 is formed via the
isolators ISC1 and ISC2, and power is supplied from the
control box ICNT to the communication units COM1 and COM2
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via the isolators ISM and ISC2. The second example of a
storage system according to the disclosure likewise exhibits
advantages similar to those of the first example discussed
above.
[0154] Although the foregoing description is for the case
in which the disclosure is applied to a module balancing
circuit, the disclosure may also be applied to cell
balancing. In other words, by respectively substituting the
battery block groups BB1 to BB14 with battery cells in the
configuration illustrated in Fig. 21 discussed earlier, a
cell balancing circuit can be realized. Advantages similar
to those of the foregoing module balancing circuit are still
obtained in the case of applying the disclosure to a cell
balancing circuit,
[0155 ] The disclosure can be applied, to a cell balancing
circuit as illustrated by the typical configuration in Fig.
32. In Fig. 32, n battery cells B11 to Bin are connected in
series, and in addition, there are m sets of the battery
cells connected in series, with the sets connected in
parallel. The primary coils of flyback transformers Til to
Tin and Tml to Tmn are connected in parallel to each battery
cell, and primary switches S11 to Sln and Sml to Smn are
connected in series to the primary coils. One end of the
secondary coil of each flyback transformer is connected to
the power supply line CL+ of a common power supply voltage
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CV, while the other end of the secondary coil is connected
in series to the power supply line CL- of the common power
supply voltage CV via respective secondary switches SOll to
SOln and SOml to SOmn.
[0156] Furthermore, the disclosure may take
configurations like the following. In an embodiment, a
power storage apparatus includes a battery block comprising
a plurality of battery cells and an isolating unit that
enables wireless information transfer regarding battery
information of the battery block. In this embodiment, the
battery information includes one of a voltage value, a
current value, or a temperature value. In this embodiment
the isolating unit includes a first card unit and a second
card unit being configured for a contactless smart card
protocol to facilitate the wireless information transfer,
the first and second card units configured to transmit the
battery information wirelessly to each other.
[0157] In an embodiment, the isolating unit includes a
first antenna mounted on a first trace layer of a printed
circuit board and electrically connected to the first card
unit and a second antenna mounted on a second trace layer of
the printed circuit board and electrically connected to the
second card unit, the second antenna being directionally
aligned with the first antenna to enable the wireless
information transfer of battery information between the
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first and second antennas. In an embodiment, the
contactless smart cart protocol includes Amplitude Shift
Keying (ASK) modulation with a carrier wave frequency of
about 13.56 kHz at a speed between 212 kbps and 424 kbps,
the carrier wave having an amplitude between 2 volts to 13
volts with a 10% degree of modulation.
[0158] In an embodiment, the isolating unit enables
wireless communication with the battery block via noncontact
smart card technology by applying Amplitude Shift
Keying (ASK) modulation to a carrier wave frequency between
10kHz and 20kHz. In an embodiment, the isolating unit
includes a controller area network (CAN) communication
protocol to facilitate the wireless information transfer.
In an embodiment, wireless information transfer includes
transfer via at least one of electromagnetic induction,
magnetic resonance, or electromagnetic radiation.
[0159 ] In an embodiment, the power storage apparatus
further includes a controller configured to measure battery
information of the battery block. In an embodiment, the
isolating unit enables wireless power transfer to power the
controller. In an embodiment, the isolating unit includes a
first antenna mounted on a first trace layer of a printed
circuit board and a second antenna mounted on a second trace
layer of the printed circuit board, the second antenna being
directionally aligned with the first antenna to enable the
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wireless information transfer of battery information between
the first and second antennas.
[0160 ] In an embodiment, the first and second antennas
are shaped in linear coil patterns. In an embodiment, the
first and second antennas are magnetically coupled through
the printed circuit board. In an embodiment, the second
antenna is connected in parallel to a resistor and a
capacitor to filter the received battery information. In an
embodiment, the first trace layer is separated from the
second trace layer by at least one insulation layer of the
printed circuit board.
[0161] In another embodiment, a power storage system
includes a first storage module including a first battery
block comprising a first plurality of battery cells and a
first isolating unit that enables wireless information
transfer regarding battery information of the first battery
block and a second storage module. In this other embodiment,
the power storage system also includes a second battery
block comprising a second plurality of battery cells and a
second isolating unit that enables wireless information
transfer regarding battery information of the second battery
block. In this other embodiment, battery information of the
first storage module is aggregated with battery information
from the second storage module.
[0162 ] In an embodiment, the battery information includes
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one of a voltage value, a current value, or a temperature
value. In an embodiment, each of the first and second
isolating units includes a first card unit and a second card
unit being configured for a contactless smart card protocol
to facilitate the wireless information transfer, the first
and second card units configured to transmit the battery
information wirelessly to each other.
[0163] In an embodiment, the power storage system further
includes a managing unit configured to aggregate the battery
information of the first storage module with the battery
information from the second storage module. In an
embodiment, the power storage system further includes a
first communication unit included within the first storage
module configured to transmit battery information of the
first battery block to the managing unit, a first controller
included within the first storage module configured to
measure the battery information of the first battery block,
a second communication unit included within the second
storage module configured to transmit battery information of
the second battery block to the managing unit, and a second
controller included within the second storage module
configured to measure the battery information of the second
battery block.
[0164 ] In an embodiment, the isolating unit enables
wireless power transfer between the first communication unit
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and the first controller to power the first controller and
between the second communication unit and the second
controller to power the second controller. In an embodiment,
each of the first and second communication units are
communicatively coupled to the managing unit via a first
wire for bidirectional communication and a second wire for
power supply.
[0165 ] In an embodiment, each of the first and second
isolating units includes a first antenna mounted on a first
trace layer of a printed circuit board and a second antenna
mounted on a second trace layer of the printed circuit board,
the second antenna being directionally aligned with the
first antenna to enable the wireless information transfer
between the first and second antennas.
[0166 ] In a further embodiment, a power storage control
apparatus includes a battery block comprising a plurality of
battery cells, a controller configured to measure battery
information of the battery block, and an isolating unit that
enables wireless communication with the controller and
wirelessly transmits power to the controller. In this
further embodiment, the battery information includes one of
a voltage value, a current value, or a temperature value.
In this embodiment, the isolating unit includes a first card
unit and a second card unit being configured for a
contactless smart card protocol to facilitate the wireless
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information transfer, the first and second card units
configured to transmit the battery information wirelessly to
each other. Also in this embodiment, the isolating unit may
include a first antenna mounted on a first trace layer of a
printed circuit board and electrically connected to the
first card unit and a second antenna mounted on a second
trace layer of the printed circuit board and electrically
connected to the second card unit, the second antenna being
directionally aligned with the first antenna to enable the
wireless information transfer between the first and second
antennas.
[0167] In an embodiment, the power storage control
apparatus further includes a second battery block comprising
a plurality of battery cells, wherein the controller is
additionally configured to measure battery information of
the second battery block. In an embodiment, the power
storage control apparatus further include a multiplexor
communicatively coupled to the controller, the multiplexor
configured to switch between the first and second battery
blocks to enable the controller to measure battery
information of, the first battery block separately from
battery information of the second battery block and an
analog-to-digital converter communicatively coupled to the
multiplexor and the controller, the analog-to-digital
converter configured to convert analog data associated with
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the battery information of the first and second battery
blocks received via the multiplexor into corresponding
digital data for the controller.
[0166] In an embodiment, the controller is configured to
actively balance a voltage level of the first and second the
battery blocks. In an embodiment, the controller is
configured to actively balance the voltage of the first and
second the battery blocks by determining a difference
between a charge potential of the first and second battery
blocks and transferring power from the battery block with a
greater charge potential to the battery block with a lower
charge potential. In an embodiment, the isolating unit is
configured to wirelessly provide power to the controller,
thereby enabling the controller to operate independent of
power stored in the battery block.
[0169] In yet another embodiment, a power storage
apparatus to power a vehicle includes a plurality of storage
modules, each storage module including at least one battery
block comprising a plurality of battery cells, a controller
configured to measure battery information of the at least
one battery block, and an isolating unit that enables
wireless communication with the controller and wirelessly
transmits power to the controller. In this embodiment, the
power storage apparatus also includes an electrical load
including an electronic transmission or a motor of a vehicle,
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the electrical load receiving power from an aggregate of
power from the plurality of storage modules.
[0170] In an embodiment, the battery information includes
one of a voltage value, a current value, or a temperature
value. In an embodiment, each of the isolating units
includes a first card unit and a second card unit being
configured for a contactless smart card protocol to
facilitate the wireless information transfer, the first and
second card units configured to transmit the battery
information wirelessly to each other.
[0171] In an embodiment, the power storage apparatus to
power the vehicle further includes a managing unit
configured to aggregate the battery information and the
power from the plurality of storage modules. In an
embodiment, the managing unit is configured to actively
balance voltage levels of the plurality of storage modules
while the electronic transmission or the motor is being used
to drive the vehicle.
[0172] In an embodiment, the isolating unit is configured
with a controller area network (CAN) communication protocol
to facilitate the wireless information transfer. In an
embodiment, the managing unit is configured to communicate
the aggregated battery information with other processors in
the vehicle via the CAN communication protocol.
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Application in the form of home power storage system
[0173 ] An example of applying the disclosure to a home
power storage system will now be described with reference to
Fig. 33. For example, in the storage system 100 of a house
101, power is supplied from centralized power systems 102
such as fossil-fuel 102a, nuclear 102b, and hydroelectric
102c to a storage apparatus 103 via a power grid 109, an
information network 112, a smart meter 107, and a power hub
108, etc. In addition, power from an independent power
source such as a home generator 104 is supplied to the
storage apparatus 103. Power supplied to the storage
apparatus 103 is stored. Power used in the house 101 is
supplied by using the storage apparatus 103. The above is
not limited to a house 101, and a similar power storage
system may also be used for a building.,
[0174] The house 101 is provided with the generator 104,
power-consuming devices 105, the storage apparatus 103, a
control apparatus 110 that controls the respective apparatus,
a smart meter 107, and sensors 111 that acquire various
information. The respective apparatus are connected by the
power grid 109 and the information network 112. Solar cells,
fuel cells, etc. may be used as the generator 104, with
generated power being supplied to the power-consuming
devices 105 and/or the storage apparatus 103. The powerconsuming
devices 105 are a refrigerator 105a, an air
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conditioner 105b, a television receiver 105c, and a water
heater 105d, etc. Additionally, electric vehicles 106 are
included among the power-consuming devices 105. The
electric vehicles 106 are an electric car 106a, a hybrid car
106b, and an electric motorcycle 106c.
[0175] For the storage apparatus 103, a battery unit of
the disclosure discussed earlier is applied. The storage
apparatus 103 includes secondary batteries or capacitors,
and may include a lithium-ion battery, for example. The
lithium-ion battery may be stationary or used in the
electric vehicles 106. The smart meter 107 is provided with
functions for measuring commercial power usage and
transmitting the measured usage to a power company. The
power grid 109 may involve one of DC power transmission, AC
power transmission, or wireless power transmission, or a
combination of a plurality of the above.
[0176 ] The various sensors 111 are a motion sensor,
illumination sensor, object sensor, power consumption sensor,
vibration sensor, contact sensor, temperature sensor, and
infrared sensor, etc. Information acquired by the various
sensors 111 is transmitted to the control apparatus 110.
With information from the sensors 111, the state of the
weather, persons, etc. can be ascertained to automatically
control the power-consuming devices 105 and minimize energy
consumption. Additionally, the control apparatus 110 is
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able to externally transmit information regarding the house
101 to a power company, etc. via the Internet.
[ 0177 ] Processes such as power line routing and AC/DC
conversion are conducted by the power hub 108. Methods of
communication on the information network 112 to which the
control apparatus 110 is connected include methods that use
a communication interface such as DART (Universal
Asynchronous Receiver-Transmitter), and methods that utilize
a sensor network according to a wireless communication
protocol such as Bluetooth (registered trademark), ZigBee,
or Wi-Fi. The Bluetooth protocol is applied to multimedia
communication and is able to communicate on one-to-many
connections. ZigBee uses the physical layer of IEEE
(Institute of Electrical and Electronics Engineers) 802.15.4.
IEEE 802.15.4 is the name of a standard, for short-range
wireless networks called PANs (Personal Area Networks) or
WPANs (Wireless PANS).
[0176] The control apparatus 110 is connected to an
external server 113. The server 113 may be managed by the
house 101, a power company, or a service provider.
Information transmitted and received by the server 113 may
be power consumption information, lifestyle pattern
information, power rates, weather information, disaster
information, and information regarding power exchanges.
Such information may be transmitted and received by a power-
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consuming device within the home (the television, for
example), or by a device outside the home (such as a mobile
phone, for example). Such information may also be displayed
on a device with display functions, such as a television,
mobile phone, or PDA (Personal Digital Assistant), for
example.
[0179] The control apparatus 110 that controls the
respective units is composed of a CPU (Central Processing
Unit), RAM (Random Access Memory), and ROM (Read-Only
Memory), etc., and is housed inside the storage apparatus
103 in this example. The control apparatus 110 is connected
to the storage apparatus 103, the home generator 104, the
power-consuming devices 105, the various sensors 111, and
the server 113 by the information network 112, and has
functions for adjusting the amounts of commercial power
usage and power generation, for example. However, the
control apparatus 110 may also be provided with other
functions besides the above, such as functions for
exchanging power on an electricity market.
[0180] As above, power from not only centralized power
systems 102 such as fossil-fuel 102a, nuclear 102b, and
hydroelectric 102c but also generated power from a home
generator 104 (solar power, wind power) can be stored in the
storage apparatus 103. Consequently, the amount of power
sent out externally can be kept constant even if there are
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fluctuations in the generated power from the home generator
104, or alternatively, it can be controlled such that power
is discharged if necessary. For example, one possible usage
scenario may involve storing power obtained by solar power
in the storage apparatus 103 while also storing nighttime
power in the storage apparatus 103 at night when rates are
lower, and discharging power stored by the storage apparatus
103 during the daytime when rates are higher.
[0181] Also note that while in this example the control
apparatus 110 is described as being housed inside the
storage apparatus 103, it may also be housed inside the
smart meter 107 or have a standalone configuration.
Furthermore, the storage system 100 may also be used with
respect to a plurality of homes in a housing complex, and
may also be used with respect to a plurality of detached
homes.
Application in the form of vehicular power storage system
[0182] An example of applying the disclosure to a
vehicular power storage system will now be described with
reference to Fig. 34. Fig. 34 schematically illustrates an
exemplary configuration of a hybrid vehicle implementing a
series hybrid system to which the disclosure has been
applied. A series hybrid system is a vehicle running on an
electric transmission that uses power generated by a
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generator driving an engine, or power that has been
temporarily stored in a battery.
[0183 ] On board the hybrid vehicle 200 are an engine 201,
a generator 202, an electric transmission 203, a drive wheel
204a, a drive wheel 204b, a wheel 205a, a wheel 205b, a
battery 208, a vehicle control apparatus 209, various
sensors 210, and a charge port 211. The earlier-discussed
battery unit of the disclosure is applied as the battery 208.
[0184] The hybrid vehicle 200 runs by taking the electric
transmission 203 as the source of motive power. A motor is
an example of the electric transmission 203. The electric
transmission 203 operates on power from the battery 208,
with the torque of the electric transmission 203 being
transmitted to the drive wheels 204a and 204b. Note that
both DC motors and AC motors may be applied as the electric
transmission 203 by using an appropriate number of DC-AC or
AC-DC conversions. The various sensors 210 control the
number of engine revolutions via the vehicle control
apparatus 209 and control the position of a throttle valve
not illustrated (throttle position). The various sensors
210 include a velocity sensor, acceleration sensor, engine
revolution sensor, etc.
[0185 ] Torque from the engine 201 is imparted to the
generator 202, and it is possible to store power generated
by the generator 202 due to the torque in the battery 208.
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[0186 ] When the hybrid vehicle is made to decelerate by a
control mechanism not illustrated, the resistance during the
deceleration is added to the electric transmission 203 as
torque, and the regenerative power generated by the electric
transmission 203 due to the torque is stored in the battery
208.
[0187] By connecting to a power source external to the
hybrid vehicle, the battery 208 is able to receive supplied
power from the external power source with the charge port
211 acting as inlet, and is also able to store received
power.
[0188 ] Although not illustrated, an information
processing apparatus that performs information processing
related to vehicle control on the basis of secondary
battery-related information may also be, provided. Such an
information processing apparatus may be an information
processing apparatus that displays the remaining battery
charge level on the basis of information related to the
remaining charge level of the battery, for example.
[0189] Herein , the foregoing describes by way of example
a series hybrid car running on a motor that uses power
generated by a generator driven by an engine or power
therefrom which has been temporarily stored in a battery.
However, this disclosure is validly applicable to parallel
hybrid cars that take the output of both an engine and a
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motor as sources of motive power and appropriately switch
usage among the three modes of running on the engine only,
running on the motor only, and running on the engine and the
motor. Furthermore, this disclosure is validly applicable
to electric vehicles, which run on the drive provided by a
driving motor only, without using an engine.
Modifications
[0190] Although the foregoing describes specific
embodiments of the disclosure, the foregoing embodiments are
not limiting, and various modifications based on the
technical ideas in this disclosure are possible. For
example, the configurations, methods, processes, shapes,
materials, and values, etc. given in the foregoing
embodiments are merely examples, and different
configurations, methods, processes, shapes, materials, and
values, etc. may be used as appropriate.
[0191] Moreover, it is possible to combine together the
configurations, methods, processes, shapes, materials, and
values, etc. of the foregoing embodiments insofar as such
combinations do not depart from the principal matter of the
disclosure.
[0192] The present disclosure contains subject matter
related to that disclosed in Japanese Priority Patent
Application JP 2011-189562 filed in the Japan Patent Office
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on August 31, 2011 and Japanese Priority Patent Application
JP 2012-062257 filed in the Japan Patent Office on March 19,
2012, the entire contents of which are hereby incorporated
by reference.
[0193] It should be understood by those skilled in the
art that various modifications, combinations, subcombinations
and alterations may occur depending on design
requirements and other factors insofar as they are within
the scope of the appended claims or the equivalents thereof.
SP327450
WHAT IS CLAIMED IS:
1. A power storage apparatus comprising:
a battery block comprising a plurality of battery
cells; and
an isolating unit that enables wireless information
transfer regarding battery information of the battery block.
2. The power storage apparatus according to claim 1,
wherein the battery information includes one of a voltage
value, a current value, or a temperature value.
3. The power storage apparatus according to claim 1,
wherein the isolating unit includes a first card unit and a
second card unit being configured for a contactless smart
card protocol to facilitate the wireless information
transfer, the first and second card units configured to
transmit the battery information wirelessly to each other.
4. Thepower storage apparatus according to claim 3,
wherein the isolating unit includes:
a first antenna mounted on a first trace layer of a
printed circuit board and electrically connected to the
first card unit; and
a second antenna mounted on a second trace layer of the
printed circuit board and electrically connected to the
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second card unit, the second antenna being directionally
aligned with the first antenna to enable the wireless
information transfer of battery information between the
first and second antennas.
5. The power storage apparatus according to claim 3,
wherein the contactless smart cart protocol includes
Amplitude Shift Keying (ASK) modulation with a carrier wave
frequency of about 13.56 kHz at a speed between 212 kbps and
424 kbps, the carrier wave having an amplitude between 2
volts to 13 volts with a 10% degree of modulation.
6. The power storage apparatus according to claim 3,
wherein the isolating unit enables wireless communication
with the battery block via non-contact smart card technology
by applying Amplitude Shift Keying (ASK) modulation to a
carrier wave frequency between l0kHz and 201-Hz.
7. The power storage apparatus according to claim 1,
wherein- the isolating unit includes a controller area
network (CAN) communication protocol to facilitate the
wireless information transfer.
8. The power storage apparatus according to claim 1,
wherein wireless information transfer includes transfer via
at least one of electromagnetic induction, magnetic
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resonance, or electromagnetic radiation.
9. The power storage apparatus according to claim 1,
further comprising a controller configured to measure
battery information of the battery block.
10. The power storage apparatus according to claim 9,
wherein the isolating unit enables wireless power transfer
to power the controller.
11. The power storage apparatus according to claim 1,
wherein the isolating unit includes:
a first antenna mounted on a first trace layer of a
printed circuit board; and
a second antenna mounted on a second trace layer of the
printed circuit board, the second antenna being
directionally aligned with the first antenna to enable the
wireless information transfer of battery information between
the first and second antennas.
12. The power storage apparatus according to claim 11,
wherein the first and second antennas are shaped in linear
coil patterns.
13. The power storage apparatus according to claim 12,
wherein the first and second antennas are magnetically
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coupled through the printed circuit board.
14. The power storage apparatus according to claim 11,
wherein the second antenna is connected in parallel to a
resistor and a capacitor to filter the received battery
information.
15. The power storage apparatus according to claim 11,
wherein the first trace layer is separated from the second
trace layer by at least one insulation layer of the printed
circuit board.
16. A power storage system comprising:
a first storage module including:
a first battery block comprising a first plurality
of battery cells; and
a first isolating unit that enables wireless
information transfer regarding battery information of the
first battery block; and
a second storage module including:
a second battery block comprising a second
plurality of battery cells; and
a second isolating unit that enables wireless
information transfer regarding battery information of the
second battery block;
wherein battery information of the first storage module
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is aggregated with battery information from the second
storage module.
17. A power storage apparatus to power a vehicle
comprising:
a plurality of storage modules,
including:
each storage module
at least one battery block comprising a plurality
of battery cells;
a controller configured to measure battery
information of the at least one battery block; and
an isolating unit that enables wireless
communication with the controller and wirelessly transmits
power to the controller; and
an electrical load including an electronic transmission
or a motor of a vehicle, the electrical load receiving power
from an aggregate of power from the plurality of storage
modules.