Claims:I/We claim:

1. A battery module (100) for a powered device comprising:
a plurality of cells enclosed in a casing (101);
at least one end cover (102) securely attached to the casing (101);
a battery management system board (206) positioned proximal to the at least one end cover (102) in the casing (101); and
a plurality of end connections (103a and 103b) removably attached to the battery management system board (206), wherein the plurality of end connections (103a and 103b) comprises:
a first end connection (103a) corresponding to power lines of the battery module (100) comprising at least one protection device (404) positioned between the power lines for providing electrical protection to the battery module (100), and
a second end connection (103b) corresponding to signal lines of the battery module (100).

2. The battery module (100) as claimed in claim 1, wherein the first end connection (103a) comprises:
a terminal holder (401) removably attached to the battery management system board (206),
a positive terminal stud (405a) and a negative terminal stud (405b) extending from the terminal holder (401) for sourcing power to electrical loads, and
the at least one protection device (404) connected to the positive terminal stud (405a) to carry current from the battery management system board (206) to the positive terminal stud (405a).

3. The battery module (100) as claimed in claim 2, wherein the positive terminal stud (405a) and the negative terminal stud (405b) project from the battery management system board (206) though the at least one end cover (102) and wherein the positive terminal stud (405a) and the negative terminal stud (405b) have different geometries.

4. The battery module (100) as claimed in claim 2,
wherein the terminal holder (401) comprises a base member (411) with at least one connector (410, 411, 413) fastened on a bottom surface of the base member (411) at predetermined fastening locations, and
wherein the one of the at least one connector (410) connects the at least one protection device (404) to the positive terminal stud (405a).

5. The battery module (100) as claimed in claim 2, wherein the first end connection (103a) carries a current from the battery management system board (206), out of the battery module (100) to electrical loads.

6. The battery module (100) as claimed in claim 1, wherein the second end connection (103b) comprises:

at least one female signal connector (207) comprising at least one hollow pin (301) securely attached to the battery management system board (206), and
at least one corresponding male signal connector (208) comprising at least one plug (302) removably engaged with the at least one hollow pin (301) of the at least one female signal connector (207) for connecting the battery module (100) to a battery controller.

7. The battery module (100) as claimed in claim 6, wherein the at least one male signal connector (208) further comprises clips for secure and tight locking of the at least one plug (302) with the at least one hollow pin (301) of the at least one female signal connector (207).

8. The battery module (100) as claimed in claim 1, wherein the second end connection (103b) facilitates parallel connection of the battery module (100) with other battery modules.

9. The battery module (100) as claimed in claim 1, wherein the end cover (102) further comprises guiders (104) and a holding clamper (105) to route power cables and signal cables connected to the first end connection (103a) and the second connection (103b) respectively.
, Description:TECHNICAL FIELD
[0001] The present subject matter relates to battery modules. More particularly, end connections of the battery modules are disclosed.

BACKGROUND
[0002] Existing research in battery technology is directed to rechargeable batteries, such as sealed, starved electrolyte, lead/acid batteries, are commonly used as power sources in different applications, such as, vehicles and the like. However, the lead-acid batteries are heavy, bulky, and have short cycle life, short calendar life, and low turn around efficiency, resulting in limitations in applications.
[0003] Thus, in order to overcome problems associated with conventional energy storage devices including the lead-acid batteries, a lithium ion battery provides an ideal system for high energy-density applications, improved rate capability, and safety. Further, the rechargeable energy storage devices - lithium-ion batteries exhibit one or more beneficial characteristics which makes it useable on powered devices. First, for safety reasons, the lithium ion battery is constructed of all solid components while still being flexible and compact. Secondly, the energy storage device including the lithium ion battery exhibits similar conductivity characteristics to primary batteries with liquid electrolytes, i.e., deliver high power and energy density with low rates of self-discharge. Thirdly, the energy storage device as the lithium ion battery is readily manufacturable in a manner that it is both reliable and cost-efficient. Finally, the energy storage device including the lithium ion battery is able to maintain a necessary minimum level of conductivity at sub-ambient temperatures.
[0004] In a known structure for an energy storage device, one or more energy storage cells including lithium ion battery cells are disposed in at least one holder structure in series and parallel combinations using at least one interconnecting structure. The interconnecting structure is adapted for electrically interconnecting the energy storage cells with a battery management system (BMS). An output voltage and an output current generated by the energy storage device is transmitted to one or more electronic and electrical components configured to be powered by the energy storage device via end connections after being monitored and regulated by the BMS. The design of the end connections is critical to the safety, serviceability, and maintainability of the energy storage device.

BRIEF DESCRIPTION OF DRAWINGS
[0005] The detailed description is described with reference to the accompanying figures. The same numbers are used throughout the drawings to reference like features and components.

[0006] Fig. 1 exemplarily illustrates a battery module.
[0007] Fig. 2 exemplarily illustrates an exploded perspective view of the battery module exemplarily illustrated in Fig. 1.
[0008] Figs. 3A-3B exemplarily illustrate perspective views of a second end connection of the battery module.
[0009] Figs. 4A-4C exemplarily illustrate perspective views of a first end connection of the battery module.
[00010] Figs. 5A-5B exemplarily illustrate a perspective sectional view of the battery module with the first end connection and the second end connection.

DETAILED DESCRIPTION OF THE INVENTION
[00011] The energy storage device is connected to subsequent energy storage devices and electrical and electronic loads of a power supply system via a plurality of end connections. Typically, the output of the energy storage cells is connected to the battery management system (BMS) circuit board by means of wires and the output voltage and the output current from the end connections connect to the electronic and electrical loads in the power supply system by means of wires. Such interconnecting wires have a potential of short circuit while assembly of the energy storage device.
[00012] To prevent occurrences of such untoward events, in the existing structures of the energy storage device, the end connections are molded into an end cover of the energy storage device. Such end connections are not removable, requiring replacement of the entire end cover in case of repair of the end connections. In some other structures of the energy storage devices, the end connections are positioned on a printed circuit board (PCB) located in the energy storage device in addition to the BMS in the energy storage device. Such PCBs are inflexible and are under stress during the assembly of the energy storage device, leading to failure of the PCB in the energy storage device. Further, additional components in the energy storage device increase the weight of the energy storage device and the cost associated with the manufacturing, servicing, and replacement of the energy storage device.
[00013] There exists a need for an improved design of an energy storage device with end connections that ensure safety during assembly, maintainability, and serviceability of the energy storage device overcoming all problems disclosed above as well as other problems of known art.
[00014] The present subject matter discloses an energy storage device, that is, a battery module comprising an improved and simplified design of end connections for facilitating connection of the battery module to a battery controller, a charging unit, or subsequent battery modules in a powered device, for example, a vehicle.
[00015] Fig. 1 exemplarily illustrates perspective view of a battery module 100. The battery module 100 comprises a plurality of cells arranged in a particular sequence in a cell holder. The cells are electrically connected in series and/or parallel configuration to form an array of cells. Such arrays of cells are electrically connected to a battery management system (BMS) within the battery module 100. The BMS is a printed circuit board with one or more integrated circuits integrally built on it as exemplarily illustrated in Fig. 2.
[00016] As exemplarily illustrated, the battery module 100 comprises an external casing 101 with a dovetail pattern that is vibration proof and shock resistant, a first end cover 102, a second end cover (not shown), and a battery pack. The dovetail pattern of the external casing 101 facilitates easy mounting and unmounting of the battery module 100 in the space in a device or powered product. The external casing 101 encloses the battery pack from top and bottom. The second end cover (not shown) and the front-end cover 102 enclose the battery pack from the rear and the front respectively.
[00017] The terminal studs of a plurality of end connections 103a and 103b extend from the first end cover 102 as exemplarily illustrated. The first-end cover 102 further comprises guiders 104 and a holding clamper 105 to route power cables 106 and signal cables connected to the end connections 103a and 103b of the battery module 100.
[00018] Fig. 2 exemplarily illustrates an exploded perspective view of the battery module 100. As exemplarily illustrated, the battery pack 204 is enclosed between the second end cover 203, the external casing 101, the first-end cover 102. The BMS board 206 is attached to one of the sides of the battery pack 204. In an embodiment, the BMS board 206 is located between the battery pack 204 and the first end cover 102. The end connections 103a and 103b are removably attached to the BMS board 206. The external casing 101 has mounting provisions for the second end cover 203 and the first end cover 102. The second end cover 203 and the first end cover 102 are fastened to the external casing 101 using a plurality of attachment means 202 and 209 respectively. As per a preferred embodiment, the attachment means can be fasteners. The battery pack 204 has mounting provisions for the BMS board 206. The BMS board 206 is screwably attached to the cell holder 204a of the battery pack 204.
[00019] The plurality of end connections 103a and 103b include a first end connection 103a and a second end connection 103b. The first end connection 103a exemplarily illustrated in Fig. 1 corresponds to the power lines of the battery module 100. The first end connection 103a is mounted on the BMS board 206. The second end connection 103b corresponds to signal lines of the battery module 100. The second end connection 103b is a two-part signal connector including a female signal connector 207 and a male signal connector 208 that is fastened to the BMS board 206.
[00020] Figs. 3A-3B exemplarily illustrate perspective view of the second end connection 103b of the battery module 100. The second end connection 103b comprises the female signal connector 207 and the corresponding male signal connector 208. The female signal connector 207 comprises at least one hollow pin, such as, six hollow pins 301 centrally located in its body. The corresponding male signal connector 208 removably engages with the female signal connector 207. The female signal connector 207 is fastened on the BMS board 206 directly using fasteners 205. The at least one hollow pins 301 are molded into the body of the female signal connector 207. Corresponding to the hollow pins 301, the BMS board 206 comprises corresponding at least one mounting provisions, such as, holes 206a to removably attach the female signal connector 207 with the pins 301 to the BMS board 206 using fasteners 205 from the surface of the BMS board 206 that is in contact with the battery pack 204. The male signal connector 208 comprises six banana plugs 302 protruding from a rear surface 208a to engage with the six pins 301 in the female signal connector 207. The hollow pin 301 of the female signal connector 207 engages with the plug 302 of the male signal connector 208. On a first surface 208b of the male signal connector 208, the six banana plugs 302 facilitate signal lines of the battery pack 204 to be accessed from outside.
[00021] Further, the male signal connector 208 comprises of clips 303 on both sides for ease in mating and disengaging of the male signal connector 208 with the female signal connector 207. For mating of the banana plugs 302 with the hollow pins 301, the inner diameter of the hollow pins 301 are greater than or engageably conforming with the diameter of the banana plugs 302 and the banana plugs 302 are inserted into the hollow space of the hollow pins 301 to achieve a operable & stable electrical contact cum connection. While mating the banana plugs 302 with the hollow pins 301, the clips 303 are pressed, for example, inwards towards the banana plugs 302. Once the banana plugs 302 are engaged with the hollow pins 301, the clips 303 are released. The clips 303 ensure secure and tight locking of the banana plugs 302 with the hollow pins 301. To disengage the banana plugs 302 from the hollow pins 301, the clips 303 are again pressed and the banana plugs 302 are pulled out from the hollow pins 301. The pins 301 correspond to the signals from the BMS board 206. The second end connection 103b facilitates parallel connection of the battery module 100 with other battery modules of similar type. Also, the second end connection 103b aids in communication of the battery module 100 to the battery controller in the powered device, for example, a vehicle.
[00022] Figs. 4A-4C exemplarily illustrate perspective views of the first end connection 206b of the battery module 100. The first end connection 206b carries current from the BMS board 206 out of the battery module 100 to electrical loads. The current from the cells in the battery pack 204 culminate into a positive terminal and a negative terminal on the BMS board 206. The first end connection 206b comprises a terminal holder 401 removably attached using at least one mounting provision 402a and 402b to the BMS board 206 of the battery module 100. As exemplarily illustrated, the terminal holder 401 is a bus bar with mounting provisions to mount at least one protection device 404, a positive terminal stud 405a, and a negative terminal stud 405b of the battery module 100. The positive terminal of the BMS board 206 is connected to the positive terminal stud 405a and the negative terminal of the BMS board 206 is connected to the negative terminal stud 405b. Between the positive terminal stud 405a and the negative terminal stud 405b, the electrical loads of the battery module 100 or a charger of the battery module 100 to recharge the battery module 100 are connected. The positive terminal stud 405a and the negative terminal stud 405b protrude through the front-end cover 102. The positive terminal stud 405a and the negative terminal stud 405b are located in a depression (not shown) in the front-end cover 102 as exemplarily illustrated in Fig. 1.
[00023] The at least one protection device 404 on the terminal holder 401 is, for example, a fuse exposed to direct currents of predetermined value. As per an embodiment, the predetermined value can be 70 Amperes. The fuse is a self-acting circuit break appliance for protection of the battery module 100 against excessive currents. Excessive currents in the battery module 100 could be due to incorrect wiring of the components within the battery module 100, shorting of the positive terminal of the BMS board 206, or overloading of the battery module 100, etc. The fuse is located in close proximity to the positive terminal of the BMS board 206 and connected to the positive terminal. The negative terminal is connected to the ground. In case of fault between the fuse and the electrical load, the fuse blows and the current flow to the loads stops. The protection device 404 is mounted using the attachment means 403a and 403b, for example, screws and nuts at the mounting provisions 406a and 406b on the terminal holder 401.
[00024] The positive terminal stud 405a and the negative terminal stud 405b are securely attached to the terminal holder 401 at designated locations on the terminal holder 401. As per an embodiment, the positive terminal stud 405a is a bolt 408a in which a conductor from the positive terminal of the BMS board 206 is placed and fastened with a nut, such as, 409 to the terminal holder 401. Similarly, as per an embodiment, the negative terminal stud 405b is a bolt 408b in which a conductor from the negative terminal of the BMS board 206 is placed and fastened with a nut, such as, 409 to the terminal holder 401. Each of the positive terminal stud 405a and the negative terminal stud 405b is fastened to the terminal holder 401 using a fastener 409, for example, a screw and a washer from bottom of the terminal holder 401. In an embodiment, each of the positive terminal stud 405a and the negative terminal stud 405b comprise gaskets 407a and 407b, such as O-ring seals for tight sealing at the positive terminal stud 405a and the negative terminal stud 405b. The gaskets 407a and 407b provide a rugged sealed connection of the terminal studs 405a and 405b from water and dust for IP67 compliance of the battery module 100.
[00025] In an embodiment, the terminal holder 401 is a plastic base member 411 to which metal connectors, such as, 410, 412, and 413 are screwably attached or over molded on a bottom surface of the plastic base member 411 at predetermined fastening locations as exemplarily illustrated in Fig. 4C. The metal connectors 412 and 413 facilitate detachably attaching the terminal holder 401 to the BMS board 206. The metal connectors 412 and 413 have the mounting provisions 402a and 402b to mount the plastic base member 411 to the BMS board 206 of the battery module 100. The metal connector 410 connects the fuse in series with the positive terminal of the BMS board 206 at the positive terminal stud 405a.
[00026] The positive terminal stud 405a and the negative terminal stud 405b extend from the plastic base member 411 through the first end cover 102 for sourcing power to external loads. The positive terminal stud 405a and the negative terminal stud 405b form the first end connection 103a exemplarily illustrated in Fig. 1. As per an embodiment, the positive terminal stud 405a and the negative terminal stud 405b have different geometries to avoid interchanging of polarities during manufacturing, assembly, or servicing of the battery module 100. In an embodiment, the positive terminal stud 405a and the negative terminal stud 405b have anti-rotation feature for ensuring tight fastening of the positive terminal stud 405a and the negative terminal stud 405b to the terminal holder 401.
[00027] Figs. 5A-5B exemplarily illustrate a perspective sectional view of the battery module 100 with the first end connection 103a and the second end connection 103b. The battery pack 204 of the battery module 100 comprises a plurality of cells 501 positioned on a cell holder structure 204a and connected in series and parallel connections using an interconnecting sheet 502 as exemplarily illustrated. The terminals of the cells 501 are connected to the interconnecting sheet 502 and connected to the BMS board 206. An enlarged view of the sectional view of the second end connection 103b is exemplarily illustrated in Fig. 5B. In the second end connection 103b, the at least one banana plug 302 of the male signal connector 208 engages with the at least one pin 301 of the female signal connector 207. The male signal connector 208 comprises locking elements or clips 303 on both sides for ease in insertion and removal of the male signal connector 208 from mating and disengaging of the male signal connector 208 with the female signal connector 207.
[00028] The positive terminal stud 405a and the negative terminal stud 405b extend from the BMS board 206 and protrude through the first end cover 102. Eye terminals of the power lines of the battery pack 204 are screwed on the terminal studs 405a and 405b. The signal lines of the battery pack 204 are soldered or crimped into the banana plugs 302. The signal lines originate from at least one of a temperature sensor installed on the battery pack 204, a current measurement of an individual cell in the battery pack 204, or a voltage level detector of an individual cell in the battery pack 204, etc.
[00029] The first end cover 102 also includes guiders 104 for guiding the cables 106 arising from the positive terminal stud 405a and the negative terminal stud 405b as exemplarily illustrated in Fig. 1. The guiders 104 are located in depressions on the first-end cover 102 to guide the cable through the depressions in the first end cover 102. The first end cover 102 has projections over the positive terminal stud 405a and the negative terminal stud 405b beyond which the positive terminal stud 405a and the negative terminal stud 405b do not extend. The guiders 104 and the projections ensure the cables 106 extending from the positive terminal stud 405a and the negative terminal stud 405b are press fit into the guiders 104 and do not bulge from the surface of the front-end cover 102 avoiding stress and damage on the cables 106, when the battery module 100 is to be compactly positioned in a powered device, for example, a vehicle. The holding clamper 105 holds the guided cables and prevents dangling of the cables 106 to avoid damage to the cables 106.
[00030] The end connections in the battery module provide technical advancement in battery technology as follows: The battery module with such first end connection and second end connection avoids interference of the signal lines with the power lines. The clampers guide the cables from the first end connection further, thereby avoiding crimping, stripping, and tangling of the cables. The first end connections and the second end connections are rugged in construction allowing multiple times of engagement and disengagement of the cables from the first end connections and the second end connections, improving durability and reliability of the battery module. The gaskets in the end connections prevents dust and water entry into the battery module through the end connections resulting in a waterproof and dust resistant battery module. The different geometries of the terminal studs in the first end connections prevents interchanging of the polarities of the terminal studs and eases assembly and servicing of the battery module, thereby saving manhours in assembly, servicing, and maintenance of the battery module. Such battery modules allow uninterrupted supply to drive the powered device as the end connections facilitate interconnection of multiple such battery modules.
[00031] Improvements and modifications may be incorporated herein without deviating from the scope of the invention.