Battery Module

Abstract

The present application provides a battery module. The battery module comprises a box, a cell assembly, an upper cover, and a BMS plate, wherein the cell assembly is provided within the box, the BMS plate is mounted within the upper cover, an opening is formed in the box, and the upper cover is installed to cover the opening; the cell assembly comprises a bracket and a cell provided within the bracket, and the BMS plate is located on the bracket and electrically connected to the cell; the battery module further comprises a protective cover, the protective cover is connected within the upper cover, the cell is sprayed toward the outer surface of the protective cover, and the protective cover is provided to surround the outer side of the BMS plate and abuts against the bracket, thereby separating the BMS plate and the cell. The battery module according to the present application separates the BMS plate and the cell through the protective cover and the bracket, thereby protecting the BMS plate and the cell well, and thus can improve safety in the event of thermal runaway of the cell, while reducing the occupied area of ​​the battery module and ensuring good structural compactness.

Description

Technology Field

[0001] This application relates to the field of battery protection technology, specifically to battery modules.

[0002] The present application claims priority to a Chinese patent application with application number 202420687540.0 filed with the Chinese Intellectual Property Office on April 3, 2024, the entire contents of said application are incorporated into the present application by reference. Background Technology

[0003] In a cylindrical battery module, to prevent thermal mutual influence between the cylindrical cells and the Battery Management System (BMS) plate, two spaced-apart chambers are typically installed within the module box. By placing the cylindrical cells and the BMS plate within these two distinct chambers, physical separation is achieved between the cylindrical cells and the BMS plate. The BMS plate refers to a circuit board that monitors and protects the cylindrical cells.

[0004] However, as the separation method using the two chambers mentioned above is adopted, a bulky box is required, which increases the occupied area of ​​the entire cylindrical battery module and reduces the structural compactness inside the box. The problem to be solved

[0005] The present application provides a battery module capable of ensuring good structural compactness and a small footprint while improving safety during thermal runaway of the cell. means of solving the problem

[0006] In a first aspect, an embodiment according to the present application provides a battery module, wherein the battery module comprises a box, a cell assembly, an upper cover, and a BMS plate, wherein the cell assembly is provided within the box, the BMS plate is mounted within the upper cover, and an opening is formed in the box, and the upper cover is installed to cover the opening; wherein the cell assembly comprises a bracket and a cell provided within the bracket, and the BMS plate is located on the bracket and is electrically connected to the cell, and the battery module comprises

[0007] The above-mentioned upper cover further includes a protective member connected thereto, wherein the cell sprays toward the outer surface of the protective member, and the protective member is configured to surround the outer side of the BMS plate and abuts the bracket, thereby separating the BMS plate and the cell. Effects of the invention

[0008] A BMS plate is mounted within an upper cover and positioned on a bracket of a cell assembly, and the cell is sprayed toward the outer surface of a protective cover; a protective cover is provided within the upper cover so that it surrounds the outer side of the BMS plate and contacts the bracket, thereby completely separating the BMS plate and the cell through the protective cover and the bracket; in the event that high-temperature, high-pressure gas is generated due to thermal runaway of the cell, the isolation action of the bracket and the protective cover prevents the generated gas from being sprayed toward the BMS plate and ensures that the BMS plate is not damaged, thereby allowing the BMS plate to immediately report a thermal runaway alarm signal, thereby buying a certain amount of time for escape and improving safety during thermal runaway; furthermore, heat generated during the operation of the BMS plate is isolated to prevent the cell from receiving heat, thereby protecting the cell well and improving the service life of the cell; By providing a protective cover between the bracket and the upper cover of the cell assembly, a large-volume box is not required compared to having two spaced-apart chambers directly inside the box; thus, the structural occupancy area of ​​the entire box is small, and structural compactness is good. Brief explanation of the drawing

[0009] FIG. 1 is a schematic diagram of the structure of a battery module provided in the present application. FIG. 2 is a schematic diagram of the exploded structure of a battery module provided in the present application. FIG. 3 is a schematic diagram of the mounting structure between the protective device and the bracket provided in the present application. FIG. 4 is a schematic diagram of the structure when the upper cover and protective device are not mounted at one viewing angle provided in the present application. FIG. 5 is a schematic diagram of the structure when the upper cover and protective device are not mounted at another viewing angle provided in the present application. Specific details for implementing the invention

[0010] The present embodiment proposes a battery module, which ensures that the overall structural compactness of the battery module is good and the occupied area is small while improving safety against thermal runaway. In the present embodiment, the battery module is a 12V cylindrical battery module.

[0011] As illustrated in FIGS. 1 and 2, the battery module comprises a box (1), a cell assembly (2), an upper cover (3), and a BMS plate (4). The cell assembly (2) is provided within the box (1), and the BMS plate (4) is mounted within the upper cover (3). An opening is formed in the box (1), and the upper cover (3) is installed to cover the opening, so that the cell assembly (2) and the BMS plate (4) can be packaged within the box (1); the cell assembly (2) includes a bracket (21) and a cell (22) provided within the bracket (21), and the BMS plate (4) is horizontally positioned on the bracket (21), and the BMS plate (4) and the cell (22) are electrically connected. In this embodiment, the BMS plate (4) and the cell (22) are both conventional structures found in existing battery modules, and their operating principles are not further described here. The BMS plate (4) is connected within the upper cover (3) through a fastener. In this embodiment, the fastener may be a bolt.

[0012] As illustrated in FIGS. 2 to 5, the battery module further includes a protective cover (8), and the cell (22) is sprayed toward the outer surface of the protective cover (8). The protective cover (8) is connected within the upper cover (3), and the protective cover (8) is provided to surround the outer side of the BMS plate (4). The protective cover (8) comes into contact with the bracket (21), thereby separating the BMS plate (4) and the cell (22) by means of the bracket (21) and the upper cover (3) that come into contact with each other. In this embodiment, the cell (22) is a cylindrical cell, and the cylindrical cell is arranged horizontally within the box (1).

[0013] Compared to the prior art, the battery module in the present embodiment has a modified physical separation structure between the BMS plate (4) and the cell (22); the BMS plate (4) is mounted within the upper cover (3) and positioned horizontally on the bracket (21) of the cell assembly (2), and a protective cover (8) is provided within the upper cover (3), and the cell (22) is sprayed toward the outer surface of the protective cover (8), and the protective cover (8) is provided to surround the outer side of the BMS plate (4) and come into contact with the bracket (21), thereby completely separating the BMS plate (4) and the cell (22) through the protective cover (8) and the bracket (21); When the cell (22) generates high-temperature, high-pressure gas due to thermal runaway, the separation action of the bracket (21) and the protective cover (8) prevents the generated gas from being sprayed onto the BMS plate (4), thereby ensuring that the BMS plate (4) is not damaged, so that the BMS plate (4) immediately reports a thermal runaway alarm signal, thereby buying a predetermined time for escape and improving safety during thermal runaway; additionally, by isolating the heat generated during the operation of the BMS plate (4) and preventing the cell (22) from receiving heat, the cell (22) is well protected and the service life of the cell (22) is improved; and by providing the protective cover (8) between the bracket (21) and the upper cover (3) of the cell assembly (2), a large volume box (1) is not required compared to having two separated chambers directly inside the box (1), so the structural occupancy area of ​​the entire box (1) is small and the structural compactness is good.

[0014] The protective device (8) and the upper cover (3) are integrally molded structures, that is, the protective device (8) and the upper cover (3) are injection-molded as a single unit. On the one hand, processing is relatively simple and convenient, and there is no need to separately mount the protective device (8) and the upper cover (3), thereby saving time and effort; on the other hand, sealing between the protective device (8) and the upper cover (3) can be ensured, preventing high-temperature, high-pressure gas generated by heat during the operation of the BMS plate (4) and thermal runaway of the cell (22) from leaking out or entering through the gap between the upper cover (3) and the protective device (8), and ensuring a separation effect between the BMS plate (4) and the cell (22). In another embodiment, the upper cover (3) and the protective device (8) may be separable structures, but are not limited thereto.

[0015] It must be explained that the upper cover (3) is generally made of a flexible material, and accordingly, the protective cover (8), which is integrally molded with the upper cover (3), is also made of a flexible material. When heat or high-temperature, high-pressure gas flows into the protective cover (8), it is easy to rapidly melt the protective cover (8) within a short period of time and damage the BMS plate (4), so the BMS plate (4) inside the protective cover (8) cannot immediately report a thermal runaway alarm signal.

[0016] In this embodiment, the upper cover (3) and the protective cover (8) are integrally injection molded from polyamide-66 (PA66) and 30% glass fiber (GF) to ensure a high melting point for the upper cover (3) and the protective cover (8), with a melting point range of 200°C to 220°C. This extends the time (10s to 12s) from the occurrence of thermal runaway until the protective cover (8) melts, thereby ensuring that the protective cover (8) takes a long time to melt, and thus provides time for the BMS plate inside the protective cover (8) to report a thermal runaway alarm signal. PA66 is a general term for polyamide 66 or nylon 66 and is a thermoplastic resin material, and GF is an abbreviation for glass fiber and is an inorganic non-metallic material with excellent performance.

[0017] As shown in FIG. 2, a plurality of spaced-apart cells (22) are provided within the bracket (21), and an arc-shaped groove configured to accommodate the cells (22) is installed within the box (1). That is, the upper and lower ends of the cells (22) are each mounted on the bracket (21) and the arc-shaped groove, respectively, thereby ensuring the mounting stability and reliability of the cells (22) within the box (1). In this embodiment, four cells (22) are provided within the box (1).

[0018] In order to save space within the box (1) and to make the overall battery module more compact, as shown in FIGS. 2 and 3, the protective cover (8) is aligned with the bracket (21), that is, the outer surface of the protective cover (8) is placed in a plane with the outer surface of the bracket (21), the cell (22) is perpendicular to the outer surface of the bracket (21), and the outer surface of the bracket (21) is provided with a slot configured to expose the injection end (221) of the cell (22) to the outside, that is, the explosion-proof structure of the cell (22) and the slot are provided to correspond to each other so that the injection end (221) of the cell (22) is sprayed outward toward the outer surface of the protective cover (8), thereby allowing the protective cover (8) to block the high temperature and high pressure gas sprayed from the injection end (221) of the cell (22).

[0019] As illustrated in FIGS. 2 to 5, the protective device (8) includes a U-shaped plate (81) and a notched plate (82), the notched plate (82) is positioned at the opening side of the U-shaped plate (81), and the U-shaped plate (81) and the notched plate (82) are each aligned and in contact with the bracket (21), thereby surrounding the BMS plate (4) inside the protective device (8) by the U-shaped plate (81) and the notched plate (82), so that the cell (22) and the BMS plate (4) can be separated. The outer surface of the U-shaped plate (81) lies in one plane with the outer surface of the bracket (21).

[0020] What needs to be explained is that by ensuring that the outer surface of the U-shaped plate (81) and the outer surface of the bracket (21) are placed on one plane, the outer surface of the U-shaped plate (81) protrudes outward relative to the outer surface of the bracket (21), and that the injection unit (221) of the cell (22) is injected outwardly toward the outer surface of the U-shaped plate (81), the path for the gas injected by the injection unit (221) to reach the U-shaped plate (81) can be increased, and furthermore, the protective device (8) can provide more time to protect the BMS plate (4), thereby allowing more time to be saved for escape.

[0021] As illustrated in FIGS. 3 to 5, the notch plate (82) is provided with an avoidance notch (821) to provide an avoidance space for the mounting block (31) of the upper cover (3), that is, the mounting block (31) is positioned on the side of the avoidance notch (821) to prevent interference between the mounting block (31) and the notch plate (82); the mounting block (31) is configured to mount a pole (5), one end of the pole (5) is electrically connected to the BMS plate (4), and the other end of the pole (5) is drawn out from the top of the upper cover (3).

[0022] As illustrated in FIGS. 1 to 3, an explosion-proof valve (7) is provided in the box (1) to directionally discharge high-temperature, high-pressure gas generated by thermal runaway of the cell (22) through the explosion-proof valve (7) and to ensure safety from thermal runaway; the explosion-proof valve (7), the notch plate (82), and the injection section (221) of the cell (22) are located on the same side of the box (1).

[0023] By providing the explosion-proof valve (7), the notch plate (82), and the injection section (221) of the cell (22) on the same side of the box (1), when the injection section (221) of the cell (22) injects gas due to thermal runaway, the large amount of gas injected is directly injected by the explosion-proof valve (7), thereby preventing the large amount of gas from being injected from the avoidance notch (821) of the notch plate (82) to the BMS plate (4), and thus ensuring the separation and protection of the notch plate (82) from the BMS plate.

[0024] As shown in FIG. 3, a U-shaped plate (81) is provided on the other side of the injection unit (221) of the cell (22), so that the gas injected by the injection unit (221) can be blocked through the U-shaped plate (81), thereby ensuring a protective effect for the BMS plate (4).

[0025] The connection location between the pole (5) and the BMS plate (4) is sealed by a sealant to prevent a gap from forming between the pole (5) and the BMS plate (4); the upper cover (3) and the box (1) are sealed by a sealant, and the connection line connected to the BMS plate (4) passes through the bracket (21) by sealing, that is, by providing a sealant between the connection line and the bracket (21) to perform a sealing connection for the entire battery module, thereby preventing high-temperature, high-pressure gas generated by the heat from the BMS plate (4) and the thermal runaway of the cell (22) from flowing here and there, so that the BMS plate (4) and the cell (22) can be better protected.

[0026] As shown in FIG. 2, the battery module further includes a bus bar (6), one end of the bus bar (6) is electrically connected to a BMS plate (4), and the other end of the bus bar (6) is electrically connected to a cell (22), that is, the current of the cell (22) flows through the bus bar (6), the BMS plate (4), and the pole (5) in turn and is transferred to the outside of the battery module for use.

[0027] In the battery module of the present embodiment, by means of the action of the protective device (8) and the bracket (21), on one hand, separation between the thermal runaway gas of the cell (22) and the BMS plate (4) is achieved, and the BMS plate (4) is not damaged so that a thermal runaway alarm signal is reported immediately, thereby allowing time to escape; on the other hand, by isolating the heat generated by the operation of the BMS plate (4) and preventing the cell (22) from receiving heat, the service life and performance of the cell (22) can be improved. Explanation of the symbols

[0028] 1 box 2-cell assembly 21-Bracket 22-cell 221-Partition 3-Upper cover 31-Mounting Block 4-BMS Plate 5-pole 6-Busbar 7-Explosion-proof valve 8-Protective gear 81-U type plate 82-Notch Plate 821-Evasion Notch

Claims

Claim 1 A battery module comprises a box (1), a cell assembly (2), an upper cover (3), and a battery management system (BMS) plate (4), wherein the cell assembly (2) is provided within the box (1), the BMS plate (4) is mounted within the upper cover (3), an opening is formed in the box (1), and the upper cover (3) is installed to cover the opening; The cell assembly (2) comprises a bracket (21) and a cell (22) provided within the bracket (21), the BMS plate (4) is located on the bracket (21) and is electrically connected to the cell (22), the battery module further comprises a protective cover (8) connected within the upper cover (3), the cell (22) is sprayed toward the outer surface of the protective cover (8), the protective cover (8) is provided to surround the outer side of the BMS plate (4) and is in contact with the bracket (21) to separate the BMS plate (4) and the cell (22), the protective cover (8) comprises a U-shaped plate (81) and a notch plate (82), the notch plate (82) is located on the opening side of the U-shaped plate (81), and the notch plate (82) is provided with an avoidance notch (821), the U-shaped plate (81) and the notch The plates (82) are battery modules that each contact the bracket (21). Claim 2 In claim 1, the battery module in which the protective device (8) and the upper cover (3) are integrally molded structures. Claim 3 In claim 2, the battery module has a melting point range of 200℃-220℃ for the protective device (8). Claim 4 A battery module according to any one of claims 1 to 3, wherein the outer surface of the protective device (8) and the outer surface of the bracket (21) are placed on one plane, and the outer surface of the bracket (21) is provided with a slot configured to expose the injection end (221) of the cell (22) to the outside, and the injection end (221) is provided to correspond to the slot as an explosion-proof structure of the cell (22). Claim 5 In claim 1, the box (1) is provided with an explosion-proof valve (7), and the explosion-proof valve (7), the notch plate (82), and the injection section (221) of the cell (22) are located on the same side of the box (1), forming a battery module. Claim 6 In claim 1, the upper cover (3) is further provided with a mounting block (31), the mounting block (31) is configured to mount a pole (5), the pole (5) is electrically connected to the BMS plate (4), and the mounting block (31) is a battery module located on the side of the avoidance notch (821). Claim 7 In claim 6, the battery module is sealed and connected between the pole (5) and the BMS plate (4). Claim 8 A battery module according to any one of claims 1 to 3, wherein the upper cover (3) and the box (1) are sealed and a connecting line connected to the BMS plate (4) passes through the bracket (21) by sealing. Claim 9 A battery module according to any one of claims 1 to 3, further comprising a busbar (6), wherein one end of the busbar (6) is electrically connected to the BMS plate (4) and the other end of the busbar (6) is electrically connected to the cell (22). Claim 10 delete

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