Claims:
1. A battery box (100), comprising:
a battery pack (106) comprising a plurality of battery cells (116A-E) housed within the battery box (100);
at least one telescopic duct (112) that is disposed at least partially within the battery box (100) and is oriented axially with respect to the battery pack (106), wherein the telescopic duct (112) comprises a plurality of tubular profiles (128A-E) arranged concentrically, wherein at least one of the plurality of tubular profiles (128A-E) comprises one or more vents (130) disposed on an associated exterior surface (132);
an actuator device (114) that is operatively coupled to the telescopic duct (112) and is configured to axially move the telescopic duct (112) from a contracted state (202) to an extended state (301) when a temperature associated with a specific battery cell (116C) in the battery pack (106) is identified to be above a designated threshold;
wherein the axial movement of the telescopic duct (112) causes a designated tubular profile (128E) of the telescopic duct (112) to be positioned in a region (302) adjacent to the specific battery cell (116C) for enabling release of a coolant fluid adapted to travel towards the region (302) via the telescopic duct for cooling the specific battery cell (116C).

2. The battery box (100) as claimed in claim 1, wherein the actuator device (114) comprises:
an actuation nut (140) comprising a threaded portion (156) and a first end (148) and a second end (150) that are coupled to the designated tubular profile (128E) of the telescopic duct (112); and
a lead screw (138) disposed within the actuation nut (140) and comprising a threaded section (154), wherein the actuation nut (140) and the lead screw (138) are disposed within a cylindrical bore (142) of the telescopic duct (112).

3. The battery box (100) as claimed in claim 2, wherein the actuator device (114) further comprises a motor (146) comprising a motor shaft (160) that is operatively coupled to a proximal end (158) of the lead screw (138), wherein the motor (146) rotates the lead screw (138) in a designated direction, in turn, causing the actuation nut (140) to move along the lead screw (138) towards a distal end (159) of the lead screw (138), wherein the motor shaft (146) rotates the lead screw (138) in a direction opposite to the designated direction, in turn, causing the actuation nut (140) to move along the lead screw (138) towards the proximal end (158) of the lead screw (138).

4. The battery box (100) as claimed in claim 3, wherein the movement of the actuation nut (140) towards the distal end (159) of the lead screw (138) causes the telescopic duct (112) to move from the contracted state (202) to the extended state (301), wherein the movement of the actuation nut (140) towards the proximal end (158) of the lead screw (138) causes the telescopic duct (112) to move from the extended state (301) to the contracted state (202).

5. The battery box (100) as claimed in claim 4, further comprising a processing unit (110) that:
determines a number of motor rotations required for positioning the designated tubular profile (128E) in the region (302) adjacent to the specific battery cell (116C) based on a stored look-up table generated during an initial calibration of the telescopic duct (112); and
actuates the motor (146) to perform the determined number of motor rotations to position the designated tubular profile (128E) in the region (302) when the temperature associated with the specific battery cell (116C) in the battery pack (106) is identified to be above a designated threshold.

6. The battery box (100) as claimed in claim 3, further comprising one or more position sensors for enabling positioning of the designated tubular profile (128E) in the region (302) adjacent to the specific battery cell (116C), wherein the one or more position sensors comprise one or more of an optical sensor, an infrared sensor, an radio-frequency identification (RFID) reader and an RFID tag, a capacitive transducer, a capacitive displacement sensor, an eddy-current sensor, a ultrasonic sensor, a grating sensor, a hall effect sensor, an inductive non-contact position sensor, a laser Doppler vibrometer, a linear variable differential transformer, a multi-axis displacement transducer, a photodiode array, a piezo-electric transducer, a potentiometer, a proximity sensor, a rotatory encoder, a string potentiometer, a confocal chromatic sensor, a proximity sensor, and one or more magnetic switches.

7. The battery box (100) as claimed in claim 5, further comprising a vent control system (502) that comprises:
one or more lids (504A-B), one or more solenoid plungers (506A-B), and one or more solenoid switches (508A-B) disposed on the associated exterior surface (132) of each of the tubular profiles (128A-E); and
a power supply unit (510) that is operatively coupled to each of the solenoid switches (508A-B), wherein each of the lids (504A-B) is configured to be in a closed state to cover an associated vent (512A-B) on the exterior surface (132) of the tubular profiles (128A-E) when all the battery cells (116A-E) are identified to be operating at temperatures within the designated threshold.

8. The battery box (100) as claimed in claim 7, wherein the power supply unit (510) is configured to supply power only to the solenoid switch (508B) when a temperature associated with a specific battery cell (116E) is identified to be above the designated threshold, which causes the solenoid plunger (506B) to move from a rest position (514) to an activated position (516), thereby moving the lid (504B) to uncover the associated vent (512B).

9. An electric system (102), comprising:
a battery box (100);
a fluid supply system (122) that is operatively coupled to the battery box (100), wherein the battery box (100) comprises:
a battery pack (106) comprising a plurality of battery cells (116A-E) housed within the battery box (106);
at least one telescopic duct (112) that is disposed at least partially within the battery box (100) and is oriented axially with respect to the battery pack (106), wherein the telescopic duct (112) comprises a plurality of tubular profiles (128A-E) arranged concentrically, wherein at least one of the plurality of tubular profiles (128A-E) comprises one or more vents (130) disposed on an associated exterior surface (132), wherein the fluid supply system (122) comprises an outlet (126) that is coupled to an inlet (124) of the telescopic duct (112) and is adapted to release a coolant fluid into the telescopic duct (112) via the inlet (124);
an actuator device (114) that is operatively coupled to the telescopic duct (112) and is configured to axially move the telescopic duct (112) from a contracted state (202) to an extended state (301) when a temperature associated with a specific battery cell (116C) in the battery pack (106) is identified to be above a designated threshold; and
wherein the axial movement of the telescopic duct (112) causes a designated tubular profile (128E) of the telescopic duct (112) to be positioned in a region (302) adjacent to the specific battery cell (116C) for enabling release of the coolant fluid adapted to travel towards the region (302) via one or more associated vents (130) for cooling the specific battery cell (116C).

10. The electric system (102) as claimed in claim 9, wherein the electric system (102) comprises one or more of an electric vehicle, a hybrid vehicle, a plug-in hybrid vehicle, an internal combustion engine based vehicle, an unmanned aerial vehicle, a robot, an autonomous vehicle, a semi-autonomous vehicle, an industrial power system, and a home-based energy supply system.

11. The electric system (102) as claimed in claim 9, wherein the actuator device (114) further comprises a motor (146) comprising a motor shaft (160) that is operatively coupled to a proximal end (158) of a lead screw (138), wherein the motor (146) rotates the lead screw (138) in a designated direction, in turn, causing the actuation nut (140) to move along the lead screw (138) towards a distal end (159) of the lead screw (138), and wherein the movement of the actuation nut (140) towards the distal end (159) of the lead screw (138) causes the telescopic duct (112) to move from the contracted state (202) to the extended state (301).

12. The electric system (102) as claimed in claim 11, wherein the battery box (100) further comprises a processing unit (110) that determines a number of motor rotations required for positioning the designated tubular profile (128E) in the region (302) adjacent to the specific battery cell (116C) based on a stored look-up table generated during an initial calibration of the telescopic duct (112), and wherein the processing unit (110) further actuates the motor (146) to perform the determined number of motor rotations to position the designated tubular profile (128E) in the region (302).

13. The electric system (102) as claimed in claim 12, wherein the battery box (100) further comprises a conduit (402) that houses the telescopic duct (112) and comprises a corresponding opening (404) disposed adjacent to each of the plurality of battery cells (116A-E), wherein the telescopic duct (112) comprises a curved portion (406) that is adapted to be positioned below a specific opening (404) disposed adjacent to the specific battery cell (116C) when a temperature associated with the specific battery cell (116C) is determined to be more than the designated threshold for cooling the specific battery cell (116C).

14. The electric system (102) as claimed in claim 13, wherein the fluid supply system (122) comprises an on-board heat, ventilation, and air conditioning system.

15. A method for operating a battery box (100) adapted to supply power to an electric system (102), comprising:
identifying a temperature associated with one or more battery cells (116A-E) in the battery box (100), wherein the battery box (100) comprises a telescopic duct (112) comprising a plurality of tubular profiles (128A-E) arranged concentrically, a processing unit (110), and an actuator device (114);
determining a number of motor rotations required for moving a designated tubular profile (128E) from the plurality of tubular profiles (128A-E) to a region (302) adjacent to a specific battery cell (116C) in the one or more battery cells (116A-E) that is determined to be operating at a temperature outside a desired temperature range by the processing unit (110); and
actuating a motor (146) to move the telescopic duct (112) from a contracted state (202) to an extended state (301) based on the determined number of motor rotations, to position the designated tubular profile (128E) at the region (302); and
releasing the coolant fluid into an inlet of the telescopic duct (112), wherein the coolant fluid travels along the telescopic duct (112) towards the region (302) to cool the battery cell (116C).

, Description:
BACKGROUND

[0001] Embodiments of the present specification relate generally to a battery box for housing a battery pack. More particularly, the present specification relates to a thermally efficient battery box for use in an electric or a hybrid electric vehicle.
[0002] Typically, internal combustion engine (ICE)-based vehicles use gasoline or diesel as fuel for their operation. However, such vehicles emit toxic substances due to incomplete combustion of fossil fuels, causing environmental pollution and health concerns to living beings. This has led to increasing focus on electric and hybrid vehicles that cause significantly lesser environmental pollution as compared to ICE-based vehicles.
[0003] Generally, a drive system of an electric vehicle includes an electric motor. The drive system of a hybrid electric vehicle, however, includes both the electric motor and the internal combustion engine. The electric motors associated with electric and hybrid electric vehicles interact with an associated vehicle engine and drive the vehicles with electrical power supplied from an onboard electrical power system, such as a battery pack. The battery pack includes one or more individual batteries that are electrically interconnected. The battery pack is typically housed within a battery box that is mounted onto a vehicle. Further, the battery box includes a number of additional electronic components and software for controlling the process of charging and discharging of the battery pack.
[0004] Each battery associated with the battery pack produces heat during charging and discharging processes. The heat produced by each battery accumulates within the battery box when the heat is not efficiently removed, causing damage to the battery, and creating a risk of fire or an explosion due to various reasons including deterioration of battery. Additionally, excessive heat accumulation affects electrochemical reactions occurring within the battery, thereby affecting the round trip efficiency, power and energy availability, battery life, and dynamic charging which impedes vehicle driving range and performance.
[0005] Present day batteries, therefore, employ certain cooling systems housed within or outside the battery box. For example, one such existing system uses a heat exchanger for removing excessive heat accumulated within the battery box. The heat exchanger includes a fluid conduit mounted internally or externally on a rear, bottom, or sidewall surface of the battery box. The existing system causes a low temperature fluid to pass iteratively through the fluid conduit based on feedback from battery box components, including electronics and sensors, to cause transfer of the heat accumulated within the battery box to the fluid. Thus, continuous circulation of the fluid through the fluid conduit achieves temperature reduction within the battery box.
[0006] Though, the existing system using the heat exchanger reduces temperature within the battery box, the existing system may not be efficient in achieving temperature uniformity among all batteries. This is because, batteries that are located in proximity of the fluid conduit would likely be at lesser temperature when compared to batteries that are located farther away from the fluid conduit, resulting in inefficient battery discharge cycles. Particularly, in certain heat exchanger-based systems, temperatures associated with batteries that are located around a center portion of the battery box would be usually high, resulting in decreased life span of those batteries. Hence, the existing system may not be efficient in achieving temperature uniformity amongst batteries, thus leading to unreliable power supply and performance.
[0007] Accordingly, there is a need for an improved system and apparatus that enables efficient and uniform cooling of batteries using simple, cost-effective, and lightweight cooling mechanisms.

BRIEF DESCRIPTION

[0008] It is an objective of the present disclosure to provide a battery box. The battery box includes a battery pack, at least one telescopic duct, and an actuator device. The battery pack includes one or more battery cells housed within the battery box. The telescopic duct is disposed at least partially within the battery box and is oriented axially with respect to the battery pack. The telescopic duct includes a plurality of tubular profiles arranged concentrically. At least one of the plurality of tubular profiles includes one or more vents disposed on an associated exterior surface. The actuator device is operatively coupled to the telescopic duct is configured to axially move the telescopic duct from a contracted state to an extended state when a temperature associated with a specific battery cell in the battery pack is identified to be above a designated threshold.
[0009] The axial movement of the telescopic duct causes a designated tubular profile of the telescopic duct to be positioned in a region adjacent to the specific battery cell for enabling release of a coolant fluid adapted to travel towards the region via the telescopic duct for cooling the specific battery cell.
[0010] The actuator device includes an actuation nut, a lead screw, and a connecting member. The actuation nut includes a threaded portion, a first end and a second end that are coupled to the designated tubular profile of the telescopic duct. The lead screw disposed within the actuation nut. Further, the lead screw includes a threaded section. The actuation nut and the lead screw are disposed within a cylindrical bore of the telescopic duct. The actuator device further includes a motor including a motor shaft that is operatively coupled to a proximal end of the lead screw.
[0011] The motor rotates the lead screw in a designated direction, in turn, causing the actuation nut to move along the lead screw towards a distal end of the lead screw. The motor shaft rotates the lead screw in a direction opposite to the designated direction, in turn, causing the actuation nut to move along the lead screw towards the proximal end of the lead screw. The movement of the actuation nut towards the distal end of the lead screw causes the telescopic duct to move from the contracted state to the extended state. The movement of the actuation nut towards the proximal end of the lead screw causes the telescopic duct to move from the extended state to the contracted state. The battery box further includes a processing unit. The processing unit determines a number of motor rotations required for positioning the designated tubular profile in the region adjacent to the specific battery cell based on a stored look-up table generated during an initial calibration of the telescopic duct. The processing unit further actuates the motor to perform the determined number of motor rotations to position the designated tubular profile in the region when the temperature associated with the specific battery cell in the battery pack is identified to be above a designated threshold.
[0012] The battery box further includes one or more position sensors for enabling positioning of the designated tubular profile in the region adjacent to the specific battery cell. The one or more position sensors include one or more of an optical sensor, an infrared sensor, an radio-frequency identification (RFID) reader and an RFID tag, a capacitive transducer, a capacitive displacement sensor, an eddy-current sensor, a ultrasonic sensor, a grating sensor, a hall effect sensor, an inductive non-contact position sensor, and a laser Doppler vibrometer. The one or more position sensors may further include one or more of a linear variable differential transformer, a multi-axis displacement transducer, a photodiode array, a piezo-electric transducer, a potentiometer, a proximity sensor, a rotatory encoder, a string potentiometer, a confocal chromatic sensor, a proximity sensor, and one or more magnetic switches.
[0013] The battery box further includes a vent control system. The vent control system includes one or more lids, one or more solenoid plungers, and one or more solenoid switches disposed on the associated exterior surface of each of the tubular profiles. The vent control system further includes a power supply unit that is operatively coupled to each of the solenoid switches. Each of the lids is configured to be in a closed state to cover an associated vent on the exterior surface of the tubular profiles when all the battery cells are identified to be operating at temperatures within the designated threshold. The power supply unit is configured to supply power only to a specific solenoid switch when a temperature associated with a specific battery cell is identified to be above the designated threshold, which causes an associated solenoid plunger to move from a rest position to an activated position, thereby moving the lid to uncover the associated vent.
[0014] It is another objective of the present disclosure to provide an electric system. The electric system includes a battery box and a fluid supply system that is operatively coupled to the battery box. The battery box includes a battery pack, at least one telescopic duct, and an actuator device. The battery pack includes one or more battery cells housed within the battery box. The telescopic duct is disposed at least partially within the battery box and is oriented axially with respect to the battery pack. The telescopic duct includes a plurality of tubular profiles arranged concentrically. At least one of the plurality of tubular profiles includes one or more vents disposed on an associated exterior surface. The fluid supply system includes an outlet that is coupled to an inlet of the telescopic duct and is adapted to release a coolant fluid into the telescopic duct via the inlet.
[0015] The actuator device is operatively coupled to the telescopic duct and is configured to axially move the telescopic duct from a contracted state to an extended state when a temperature associated with a specific battery cell in the battery pack is identified to be above a designated threshold. The axial movement of the telescopic duct causes a designated tubular profile of the telescopic duct to be positioned in a region adjacent to the specific battery cell for enabling release of a coolant fluid adapted to travel towards the region via one or more associated vents for cooling the specific battery cell.
[0016] The electric system includes one or more of an electric vehicle, a hybrid vehicle, a plug-in hybrid vehicle, an internal combustion engine based vehicle, an unmanned aerial vehicle, a robot, an autonomous vehicle, a semi-autonomous vehicle, an industrial power system, an aircraft, a rocket and a home-based energy supply system. The actuator device further includes a motor including a motor shaft that is operatively coupled to a proximal end of a lead screw. The motor rotates the lead screw in a designated direction, in turn, causing the actuation nut to move along the lead screw towards a distal end of the lead screw. The movement of the actuation nut towards the distal end of the lead screw causes the telescopic duct to move from the contracted state to the extended state. The battery box further includes a processing unit that determines a number of motor rotations required for positioning the designated tubular profile in the region adjacent to the specific battery cell based on a stored look-up table generated during an initial calibration of the telescopic duct. The processing unit also actuates the motor to perform the determined number of motor rotations to position the designated tubular profile in the region.
[0017] The battery box further includes a conduit that houses the telescopic duct and including a corresponding opening disposed adjacent to each of the plurality of battery cells. The telescopic duct includes a curved portion that is adapted to be positioned below a specific opening disposed adjacent to the specific battery cell when a temperature associated with the specific battery cell is determined to be more than the designated threshold for cooling the specific battery cell. The fluid supply system may include an on-board heat exchanger, ventilation, and air conditioning system.
[0018] It is yet another objective of the present disclosure to provide a method for operating a battery box adapted to supply power to an electric system. The method includes identifying a temperature associated with one or more battery cells in the battery box. The battery box includes a telescopic duct including a plurality of tubular profiles arranged concentrically, a processing unit, and an actuator device. The method further includes determining a number of motor rotations required for moving a designated tubular profile from the plurality of tubular profiles to a region adjacent to a specific battery cell in the one or more battery cells that is determined to be operating at a temperature outside a desired temperature range by the processing unit.
[0019] A motor is actuated to move the telescopic duct from a contracted state to an extended state based on the determined number of motor rotations, to position the designated tubular profile at the region. The coolant fluid is released into an inlet of the telescopic duct. The coolant fluid travels along the telescopic duct towards the region to cool the battery cell.

DRAWINGS

[0020] These and other features, aspects, and advantages of the claimed subject matter will become better understood when the following detailed description is read with reference to the accompanying drawings in which like characters represent like parts throughout the drawings, wherein:
[0021] FIG. 1 is a front view illustrating an exemplary battery box mounted onto an electric system, in accordance with aspects of the present disclosure;
[0022] FIG. 2 is a front view of the exemplary battery box of FIG. 1 having a telescopic duct that is disposed in a contracted state, in accordance with aspects of the present disclosure;
[0023] FIG. 3 is a front view of the exemplary battery box of FIG. 1 having the telescopic duct disposed in an extended state for cooling one or more specific battery cells, in accordance with aspects of the present disclosure;
[0024] FIG. 4 is a front view of the exemplary battery box of FIG. 1 including a conduit that houses the telescopic duct for cooling one or more specific battery cells, in accordance with aspects of the present disclosure; and
[0025] FIG. 5 illustrates an exploded view of a portion of the battery box of FIG. 1 including a vent control system, in accordance with aspects of the present disclosure.

DETAILED DESCRIPTION

[0026] The following description presents an exemplary battery box housing a battery pack. Particularly, the embodiments presented herein describe a thermally efficient battery box including one or more telescopic ducts for selectively cooling one or more battery cells housed within a battery box. It may be noted that the present battery box having the battery pack is used for supplying electric power for operation of various systems. Examples of such systems include an electric vehicle, a hybrid electric vehicle, a plug-in hybrid vehicle, an internal combustion engine based vehicle, an autonomous vehicle, and a semi-autonomous vehicle.
[0027] Further, the term “vehicle” includes, but is not limited to, a car, a bus, a truck, a robot, an unmanned aerial vehicle, a watercraft such as a ship or a boat, an off-road vehicle, a rocket, and an aircraft. Although, the present battery box having the battery pack may be used for supplying electric power to several other industrial or home-based electrical systems, for clarity, the present disclosure describes an embodiment of the battery box in the context of an electric vehicle.
[0028] Generally, battery cells associated with the battery pack produce heat during charging and discharging process. Therefore, as noted previously, present day battery cells employ certain cooling systems that use a heat exchanger device for removing excessive heat accumulated within the battery box. However, heat exchanger-based cooling systems may not be efficient in achieving temperature uniformity amongst all batteries, leading to unreliable power supply and performance. Unlike such heat exchanger-based cooling systems, embodiments of the present battery box system include one or more telescopic ducts that are simple, cost-effective, and lightweight mechanisms that enable efficient and uniform cooling of batteries, as described greater detail with reference to FIG. 1.
[0029] FIG. 1 illustrates a front view depicting an exemplary battery box (100) disposed within an electric system (102). In one embodiment, the electric system (102) includes an electric vehicle (102). However, as noted previously, the electric system (102) can also include a hybrid vehicle, a plug-in hybrid vehicle, an internal combustion engine based vehicle, an autonomous vehicle, a semi-autonomous vehicle, and an industrial or a home-based energy supply system.
[0030] In one embodiment, the battery box (100) is disposed below a passenger compartment seat of the electric vehicle (102). In another embodiment, the battery box (100) is disposed under a floor associated with a passenger compartment of the electric vehicle (102). However, it is to be understood that the battery box (100) may also be disposed at any other suitable location within the electric vehicle (102). For example, the battery box (100) may be disposed in a vehicle’s storage space, also known as a vehicle boot.
[0031] In certain embodiments, the battery box (100) includes a battery pack (106), one or more temperature sensors (108A-E), a processing unit (110), one or more telescopic ducts (112) that may be oriented axially at an offset distance with respect to the battery pack (106), and one or more actuator units (114). The battery box (100) further includes a lid (115) for opening and closing the battery box (100), and one or more fans (117) that dissipate heat generated during charging and discharging cycle of the battery pack (106) via an outlet (119) disposed on a wall surface (120) of the battery box (100). In one embodiment, the battery pack (106) generates and delivers a desired amount of voltage and power for aiding operation of the electric vehicle (102). The battery pack (106) includes a plurality of rechargeable battery cells (116A-E) that are connected in one or more of a series connection and a parallel connection. Exemplary types of the battery cells (116A-E) housed within the battery box (100) include one or more of lithium-ion, lithium-ion polymers, lead-acid, nickel-cadmium, nickel metal hydride, zinc-air, and molten-salt battery cells.
[0032] For simplicity, FIG. 1 depicts only one set of five battery cells (116A-E) housed within the battery box (100). However, it is to be understood that the battery box (100) may include multiple sets of battery cells and a total number of the battery cells (116A-E) housed within the battery box (100) may vary, for example, depending on the desired amount of voltage and power to be generated. Further, the battery cells (116A-E) produce heat during charging and discharging of energy stored in the battery pack (106). Hence, one or more of the battery cells (116A-E) may not be always operating in a desired temperature range. Accordingly, the battery box (100) includes the one or more temperature sensors (108A-E) that measure a temperature value associated with each of the battery cells (116A-E) continuously or at determined intervals of time.
[0033] In one embodiment, each of the battery cells (116A-E) includes an associated temperature sensor. For example, the battery box (100) depicted in FIG. 1 includes five temperature sensors (108A-E) each of which measures a temperature value of an associated battery cell. For example, the temperature sensor (108A) measures temperature associated with the battery cell (116A). The other temperature sensors (108B, 108C, 108D, and 108E) measure temperature associated with the battery cells 116B, 116C, 116D, and 116E, respectively. However, in an alternative embodiment, the temperature sensor (108A) may be adapted to measure a temperature value associated with more than one battery cell, for example battery cells (116 A-B) in the battery box (100), to enable temperature measurements using fewer temperature sensors (108A-E).
[0034] In certain embodiments, each of the temperature sensors (108A-E) is communicatively coupled to the processing unit (110). The processing unit (110) may be implemented by suitable code on a processor-based system. Accordingly, the processing unit (110), for example, includes one or more microcontrollers, microprocessors, programming logic arrays, field programming gate arrays, and/or other suitable computing devices. The processing unit (110) receives temperature values measured by the temperature sensors (108A-E). In certain embodiments, the processing unit (110) includes an associated memory (118) that pre-stores a desired temperature range for safe operation and discharge of each of the battery cells (116A-E). The processing unit (110) compares the measured temperature value associated with each of the battery cells (116A-E) with the desired temperature range. The processing unit (110) then identifies one or more specific battery cells (116C) that operate at temperature values outside the desired temperature range. Subsequently, the processing unit (110) actuates a cooling system for cooling one or more specific battery cells (116C) operating at temperature values above the desired temperature range, as described in detail with reference to FIGS. 2 and 3.
[0035] In one embodiment, the cooling system includes the one or more telescopic ducts (112), the one or more actuator units (114), and a fluid supply system (122). For simplicity, FIG. 1 depicts only a single telescopic duct (112) and a single actuator unit (114). However, the battery box (100) can have more than one telescopic duct (112) and more than one actuator unit (114). In certain embodiments, an inlet (124) of the telescopic duct (112) is coupled to an outlet (126) of the fluid supply system (122). The fluid supply system (122) may be disposed inside or outside of the battery box (100). An example of the fluid supply system (122) includes an on-board heat exchanger, ventilation, and air conditioning system that introduces cooling air into the inlet (124) of the telescopic duct (112). The telescopic duct (112), in turn, carries the cooling air to a region adjacent to a specific battery cell (116C) operating at an abnormal temperature.
[0036] To that end, the telescopic duct (112) includes a plurality of concentrically arranged tubular profiles. For example, the telescopic duct (112) depicted in FIG. 1 includes five exemplary tubular profiles including a first tubular profile (128A), a second tubular profile (128B), a third tubular profile (128C), a fourth tubular profile (128D), and a fifth tubular profile (128E). The first tubular profile (128A) accommodates the second tubular profile (128B), which axially moves in and out of the first tubular profile (128A). Similarly, each of the second tubular profile (128B), the third tubular profile (128C), and the fourth tubular profile (128D) moveably accommodate the third tubular profile (128C), the fourth tubular profile (128D), and the fifth tubular profile (128E), respectively.
[0037] Though the telescopic duct (112) depicted in FIG. 1 includes only five tubular profiles, it is to be understood that the telescopic duct (112) can have any number of tubular profiles. For example, the telescopic duct (112) can have two or ten tubular profiles. According to aspects of the present disclosure, each of the tubular profiles (128A-E) includes one or more vents (130) disposed on an associated exterior surface (132). In certain embodiments, the telescopic duct (112) is mounted onto a wall surface (134) of the battery box (100) using a mounting structure, for example, including bolts and nuts, which are not shown in FIG. 1. In addition, though the tubular profiles (128A-E) in FIG. 1 are depicted as conical in shape, it is to be understood that the tubular profiles (128A-E) can be of any other shape such as a circle, rectangle, or square. For example, the telescopic duct (112) may have the tubular profiles (128A-E) that are square in shape and are stacked or concentrically arranged.
[0038] In one embodiment, the telescopic duct (112) is disposed in a contracted state (202) (shown in FIG. 2) within the battery box (100) when all the battery cells (116A-E) are operating in the desired temperature range. However, the telescopic duct (112) may be automatically actuated to expand from the contracted state to an extended state (301) (shown in FIG. 3) by the processing unit (110) using the actuator unit (114) when one or more specific battery cells (116C) are determined to be operating at temperature values above the desired temperature range. To that end, the telescopic duct (112) is operatively coupled to the actuator unit (114).
[0039] In one embodiment, the actuator unit (114) includes a lead screw (138) and an actuation nut (140) that are disposed within a cylindrical bore (142) (shown with dotted lines) associated with the telescopic duct (112), and a motor (146) that may be located inside or outside of the battery box (100). In one embodiment, the actuation nut (140) includes a first end (148) and a second end (150), both of which are coupled to an inner surface of the fifth tubular profile (128E). Further, the actuation nut (140) includes a threaded hole that houses the lead screw (138).
[0040] The lead screw (138) includes a threaded section (154) whose pitch matches with a pitch of a threaded portion (156) of the actuation nut (140). In one embodiment, the actuator unit (114) further includes one or more ball bearings (not shown in FIGS) disposed within a gap existing between the threaded section (154) of the lead screw (138) and the threaded portion (156) of the actuation nut (140). The one or more ball bearings ensure that the actuation nut (140) moves smoothly along the lead screw (138) and prevent lateral movements of the actuation nut (140). The lead screw (138) supports the tubular profiles (128A-E) of the telescopic duct (112). Moreover, a proximal end (158) of the lead screw (138) is coupled to a motor shaft (160) associated with the motor (146), for example, via a bracket (not shown in FIG. 1). In one embodiment, the lead screw (138) including the associated proximal end (158) and the distal end (159) are coupled to the wall surface (134) of the battery box via corresponding mechanical members, for example including bearings (not shown in FIGS), for supporting and mounting the lead screw (138) onto the wall surface (134) of the battery box (100). According to aspects of the present disclosure, the motor (146) actuates rotation of the motor shaft (160) under the control of the processing unit (110) when a temperature value associated with a specific battery cell (116C) is above a designated threshold range.
[0041] The rotation of the motor shaft (160) causes the lead screw (138) to rotate in a designated direction. The rotation of the lead screw (138), in turn, causes the actuation nut (140) to slide along the lead screw (138) and move towards a distal end (159) of the lead screw (138). As the actuation nut (140) and the telescopic duct (112) are coupled, movement of the actuation nut causes the telescopic duct (112) to move from the contracted state (202) to the extended state (301). In one embodiment, the processing unit (110) controls an extent to which the telescopic duct (112) is to be moved from the contracted state (202) to the extended state (301) for cooling the specific battery cell (116C). An exemplary mechanism for controlling the extent of movement of the telescopic duct (112) is described in greater detail with reference to FIGS. 2 and 3.
[0042] FIG. 2 illustrates a front view of the exemplary battery box (100) of FIG. 1 having the telescopic duct (112) disposed in a contracted state (202). In one embodiment, the telescopic duct (112) is disposed in the contracted state (202) when all the battery cells (116A-E) within the battery box (100) are operating within the desired temperature range. However, as noted previously, the processor unit (110) activates the actuator unit (114) when a temperature value associated with a particular battery cell (116C) is identified to be above the desired temperature range. Activation of the actuator unit (114) causes the telescopic duct (112) to move from the contracted state (202) to the extended state (301), further causing release of the cooling fluid via the one or more vents (130) for cooling the battery cell (116C), as described in detail with reference to FIG. 3.
[0043] FIG. 3 illustrates a front view of the exemplary battery box (100) of FIG. 1 when the telescopic duct (112) is disposed in the extended state (301) for cooling the battery cell (116C). In one embodiment, the temperature sensors (108A-E) disposed within the battery box (100) are configured to measure temperature values associated with the battery cells (116A-E) continuously or at designated intervals of time. The processing unit (110) compares the measured temperature values received from the temperature sensors (108A-E) with one or more desired temperature ranges that are pre-stored in the associated memory (118), and identifies one or more specific battery cells that are operating at temperature values above their desired temperature range.
[0044] For example, the processing unit (110) identifies that a specific battery cell (116C) is operating at a temperature that is above its desired temperature range. Subsequently, the processing unit (110) determines a number of motor rotations required to position a designated tubular profile, for example, the fifth tubular profile (128E) in a region (302) adjacent to the specific battery cell (116C). It may be noted that the telescopic duct (112) is mounted fixedly to the wall surface (134) of the battery box (100) at a reference point (304) and is pre-calibrated to determine the number of rotations needed to position the fifth tubular profile (128E) adjacent to the different battery cells (116A-E) within the battery box (100).
[0045] Accordingly, upon identifying the specific battery cell (116C) operating at a temperature that is above its desired temperature range, the processing unit (110) transmits control signals to actuate the motor (146). Actuation of the motor (146) rotates the motor shaft (160), causing the lead screw (138) to rotate in a designated direction. Rotation of the lead screw (138) triggers a linear motion of the actuation nut (140) towards the distal end (159) of the lead screw (138), resulting in the telescopic duct (112) moving from the contracted state (202) to the extended state (302) towards the distal end (159), as noted previously with reference to FIG. 1.
[0046] According to aspects of the present disclosure, movement of the telescopic duct (112) is pre-calibrated during initial deployment. Specifically, as the telescopic duct (112) moves towards the distal end (159), a number of motor rotations that caused the fifth tubular profile (128E) to be positioned adjacent to each of the plurality of battery cells (116A-E) is noted during initial calibration. For example, during initial calibration, it may be observed that positioning the fifth tubular profile (128E) adjacent to the first battery cell (116A), the second battery cell (116B), the third battery cell (116C), the fourth battery cell (116D), and the fifth battery cell (116E) requires 10 rotations, 20 rotations, 30 rotations, 40 rotations, and 50 rotations, respectively. At the end of the initial calibration, the processing unit (110) stores these observations as a look-up table in the memory (118).
[0047] Subsequently, the processing unit (110) may simply look-up the number of motor rotations required to position the fifth tubular profile (128E) in the region (302) adjacent to the specific battery cell (116C) to be 30 rotations using the stored look-up table. The processing unit (110) then actuates the motor to undergo 30 rotations so as to position the fifth tubular profile (128E) in the region (302) adjacent to the specific battery cell (116C). The processing unit (110) also controls a speed at which the motor shaft (160) rotates for adjusting a time taken for positioning the fifth tubular profile (128E) in the region (302).
[0048] Further, as previously noted, the inlet (124) of the telescopic duct is coupled to the outlet (126) of the fluid supply system (122). Once the requisite rotations position the fifth tubular profile (128E) in the region (302) adjacent to the specific battery cell (116C), the processing unit (110) activates the fluid supply system (122) to transmit cooling fluid through the telescopic duct (112). Consequently, the cooling fluid supplied by the fluid supply system (122) enters the inlet (124) of the telescopic duct (112) and travels to the region (302) via the extended fifth tubular profile (128E). In particular, the telescopic duct (112) releases the cooling fluid in the region (302) via the one or more vents (130) disposed on the exterior surface (132) of the fifth tubular profile (128E), thus causing the cooling fluid to come in contact with the battery cell (116C) operating at a higher temperature. The cooling fluid released via the one or more vents (130) cools the battery cell (116C) and helps in controlling the associated temperature to be within the desired temperature range.
[0049] In certain embodiments, the processing unit (110) enables the release of cooling fluid until the temperature value associated with the battery cell (116C) reverts back to a temperature value that is within the desired temperature range. Subsequently, the processing unit (110) terminates the release of the cooling fluid and further actuates the motor shaft (160) to rotate in a desired direction that is opposite to the direction of rotation of the motor shaft (160) during extension of the telescopic duct (112) towards the distal end (159). Rotation of the motor shaft (160) in the opposite direction causes the telescopic duct (112) to move back from the extended state (301) to the contracted state (202). In an alternative embodiment, however, the telescopic duct (112) may be further extended or may only be partially contracted to cool down another battery cell (116D) disposed in a different region (306) relative to the region (302) in the battery box (100).
[0050] Though FIG. 3 depicts the exemplary telescopic duct (112) in the extended state (301) for cooling the third battery cell (116C), it is to be understood that the telescopic duct (112) can be used to cool any battery cells within the battery box (100). For example, for cooling the battery cell (116D), the processing unit (110) controllably actuates the motor (146) to undergo 40 rotations based on a number of rotations data stored in the look-up table for enabling the fifth tubular profile (128E) to be positioned in a region (306) adjacent to the battery cell (116D). Further, the processing unit (110) causes release of the cooling fluid into the telescopic duct (112) that carries the cooling fluid to the region (306) via the one or more vents (130) in the fifth tubular profile (128E) for cooling the battery cell (116D). The processing unit (110) may enable the telescopic duct (112) to release the cooling fluid via one or more associated vents (130) when the telescopic duct is in the contracted state (202), in the expanded state (301), moving from the contracted state (202) to the expanded state (301), or moving from the expanded state (301) to the contracted state (202).
[0051] In one embodiment, the battery box (100) includes one or more sensors for extending the telescopic duct (112) and positioning the fifth tubular profile (128E) in the region (302) adjacent to the battery cell (116C) determined to be operating at a temperature level above than the desired temperature range. An example of the one or more sensors includes an RFID tag (308) and an RFID reader (310) disposed within the battery box (100). Specifically, the RFID tag (308) may be disposed on the exterior surface (132) of the fifth tubular profile (128E) and the RFID reader (310) may be disposed in proximity to the distal end (159) of the lead screw (138).
[0052] In one embodiment, the RFID reader (310) measures a strength of an RFID signal received from the RFID tag (308) fixed to the fifth tubular profile (128E) and enables the processing unit (110) to identify a position of the fifth tubular profile (128E) based on the measured signal strength. For example, in the embodiment depicted in FIG. 3, the measured signal strength would be low when the telescopic duct (112) is in the contracted state (202). However, the measured signal strength would gradually increase as the telescopic duct (112) extends towards the distal end (159). The processing unit (110) identifies and tracks the position of the fifth tubular profile (128E) based on the measured signal strength. In addition, the processing unit (110) stops the operation of the motor (146) upon determining that the fifth tubular profile (128E) has reached the region (302) adjacent to the specific battery cell (116C). The processing unit (110) then enables the release of cooling fluid towards the region (302) for cooling the specific battery cell (116C).
[0053] In one embodiment, the battery box (100) may include other types of sensors, for example, one or more position sensors, optical sensors, and/or infrared sensors instead of the RFID tag (308) and the RFID reader (310) for appropriately positioning the fifth tubular profile (128E) in the region (302) adjacent to the battery cell (116C) operating at an abnormal temperature. Additional examples of one or more position sensors include a capacitive transducer, capacitive displacement sensor, eddy-current sensor, ultrasonic sensor, grating sensor, hall effect sensor, inductive non-contact position sensor, laser Doppler vibrometer, linear variable differential transformer, multi-axis displacement transducer, photodiode array, piezo-electric transducer, potentiometer, proximity sensor, rotatory encoder, string potentiometer, confocal chromatic sensor, proximity sensor, and magnetic switches. The processing unit (110) receives outputs from one or more of the previously mentioned position sensors through a corresponding method of feedback and causes extension of the telescopic duct (112) to one or more specific battery cells (116A-E) operating at temperatures above than a designated threshold.
[0054] Further, FIG. 4 illustrates a front view of an exemplary embodiment of the battery box (100) of FIG. 1 including a conduit (402) that houses the telescopic duct (112) for cooling one or more specific battery cells (116A-E). In one embodiment, the conduit (402) includes a corresponding opening (404) disposed adjacent to each of the plurality of battery cells (116A-E) in lieu of the one or more vents (130) associated with the fifth tubular profile (128E). Further, the fifth tubular profile (128E) of the telescopic duct (112) includes a curved portion (406). When a temperature associated with a particular battery cell (116D) is determined to be more than the desired temperature range, the processing unit (110) activates the actuator unit (114)to extend the telescopic duct (112) to position the curved portion (406) below the opening (404) disposed adjacent to the battery cell (116D).
[0055] In addition, the processing unit (110) activates the fluid supply system (122) to release the cooling fluid that travels through the telescopic duct (112 towards the curved portion (406) positioned below the opening (404). In one embodiment, the telescopic duct (112) is made of plastic material for providing flexibility to the telescopic duct (112). The cooling fluid travels further along the curved portion (406) and escapes through the opening (404), thus coming in contact with an exterior surface of the battery cell (116D) and cooling the battery cell (116D). Though, a shape associated with the portion (406) is shown as a circular section in FIG. 4, it is to be understood that the portion (406) can also be configured in other shapes, for example, including a square, a prism, or a cone.
[0056] In certain embodiments, the telescopic duct (112) is coupled to an extinguisher supply system (408) that supplies a fire extinguishing material in the event of any fire accident occurring within the battery box (100). The telescopic duct (112) carries the fire extinguishing material such as water, carbon dioxide, wet chemical, or foam to a specific zone within the battery box (100) where the fire accident has occurred for extinguishing the fire.
[0057] In certain embodiments, the telescopic duct (112) additionally includes a vent control system for selectively cooling a particular battery cell (116D) or simultaneously cooling more than one specific battery cell from the battery cells (116D-E). An embodiment of the vent control system is described in greater detail with reference to FIG. 5.
[0058] FIG. 5 illustrates an exploded view (500) of a portion of the battery box (100) of FIG. 1 including a vent control system (502). In one embodiment, the vent control system (502) includes one or more lids (504A-B), one or more solenoid plungers (506A-B), one or more solenoid switches (508A-B), and a power supply unit (510). Specifically, FIG. 5 depicts an embodiment of the battery box (100) in which the lids including a first lid (504A) and a second lid (504B) are disposed on the fourth tubular profile (128D) and the fifth tubular profile (128E), respectively. Further, the first lid (504A) is disposed adjacent to a first vent (512A) disposed on the fourth tubular profile (128D) and the second lid (504B) is disposed adjacent to a second vent (512B) disposed on the fifth tubular profile (128E).
[0059] In addition, the first lid (504A) is operatively coupled to a corresponding solenoid plunger (506A) and a corresponding solenoid switch (508A). Similarly, the second lid (504B) is operatively coupled to a corresponding solenoid plunger (506B) and a corresponding solenoid switch (508B). Moreover, the solenoid switches (508A-B) are operatively coupled to the power supply unit (510).
[0060] In one embodiment, the temperature sensor (108D) identifies that the battery cell (116D) is operating at a temperature above than a designated threshold. In this example, the processing unit (110) enables the power supply unit (510) to supply power only to the solenoid switch (508A), which causes the associated solenoid plunger (506A) to move from a rest position (514) to an activated position (516). The movement of the solenoid plunger (506A) from the rest position (514) to the activated position (516) causes the first lid (504A) to open the first vent (512A), and thus, allow the cooling fluid to exit via the first vent (512A) for cooling the battery cell (116D).
[0061] In another example, the temperature sensor (108D) identifies that both the battery cells (116D-E) are operating at temperatures above than the designated threshold. In this example, the processing unit (110) enables the power supply unit (510) to supply power to both the solenoid switches (508A-B), which causes the associated solenoid plungers (506A-B) to move from the rest position (514) to the activated position (516). The movement of the solenoid plungers (506A-B) from the rest position (514) to the activated position (516) causes the lids (504A-B) to open the corresponding vents (512A-B), and thus, allow the cooling fluid to exit via the vents (512A-B) for simultaneously cooling the battery cells (116D-E). In one embodiment, the solenoid plungers (506A-B) rise upwards from the rest position (514) to the activated position (516) for opening the corresponding vents (512A-B) upon supplying power to the corresponding solenoid switches (508A-B). In another embodiment, the solenoid plungers (506A-B) undergo sliding movement in lieu of rising upwards from the rest position (514) to the activated position (516) for opening the corresponding vents (512A-B) when the power supply unit (510) supplies power to the corresponding solenoid switches (508A-B). Further, it may be noted that the power supply unit (510) does not supply power to the solenoid switches associated with other tubular profiles (128A-C) (not shown in FIGS) in such a scenario. Thus, the solenoid plungers associated with the tubular profiles (128A-C) remain inactive, and hence, the lids disposed on the tubular profiles (128A-C) remain closed. In one embodiment, the battery box (100) may use a hollow pipe in lieu of the telescopic duct (112) for releasing the cooling fluid in proximity to one or more specific battery cells (116A-E) operating at temperatures above a corresponding designated threshold.
[0062] The telescopic duct (112) of the present disclosure is a simple mechanism that can be used for cooling multiple battery cells (116A-E). Further, the telescopic duct (112) is made of one or more materials such as plastics or aluminium that are light in weight and possess fire –retardant properties. Unlike certain existing cooling systems that use large heat exchangers for removing excess heat from batteries, the battery box (100) of the present disclosure includes one or more lightweight telescopic ducts for selectively cooling one or more battery cells (116A-E). Hence, a weight associated with the battery box (100) is comparatively lesser than a conventional battery box that uses a heat exchanger resulting in improvements in driving range and performance of the electric vehicle (102).
[0063] Furthermore, as noted previously, conventional battery boxes using heat exchangers often fail to achieve temperature uniformity among all battery cells. In contrast, the present battery box (100) employs the telescopic duct (112) that is capable of extending to a corresponding region adjacent to each of the battery cells (116A-E) within the battery pack (106). Consequently, use of the telescopic duct (112) allows for localized cooling of the battery cells (116A-E) to ensure temperature uniformity amongst all the battery cells (116A-E), thereby leading to significant improvement in battery life and performance. The telescopic duct (112) can be used in addition to other existing cooling systems in the electric vehicle (102), for example, cold plate based battery-cooling systems, and serpentine pipe based battery-cooling systems for cooling the battery cells (128A-E).
[0064] Although specific features of various embodiments of the present systems and methods may be shown in and/or described with respect to some drawings and not in others, this is for convenience only. It is to be understood that the described features, structures, and/or characteristics may be combined and/or used interchangeably in any suitable manner in the various embodiments shown in the different figures.
[0065] While only certain features of the present systems and methods have been illustrated and described herein, many modifications and changes will occur to those skilled in the art. It is, therefore, to be understood that the appended claims are intended to cover all such modifications and changes as fall within the true spirit of the claimed invention.