Battery pack

Abstract

A battery pack (100), comprising: a housing (10) provided with an accommodating space (101); a battery module (20) arranged in the accommodating space (101); a BMS module (30) spaced apart from the battery module (20); and an isolation plate (40) provided between the battery module (20) and the BMS module (30) and sealedly connected to the housing (10) so as to isolate the battery module (20) from the BMS module (30).

Description

battery pack

[0001] This application claims priority to the Chinese patent application filed with the China Patent Office on March 27, 2024, with application number 202420619072.3. The entire contents of the above application are incorporated by reference into this application. Technical Field

[0002] The present application relates to the technical field of battery packs, and in particular to a battery pack. Background Art

[0003] The Battery Management System (BMS) plays a vital role in the health and safety of batteries. Failures in the BMS or problems with the batteries themselves can lead to a phenomenon known as thermal runaway, damaging the BMS. SUMMARY OF THE INVENTION

[0004] In related technologies, due to cost considerations and space limitations of battery packs, battery pack designs are often simple and highly integrated, and there are deficiencies in the protection design during thermal runaway.

[0005] The embodiments of the present application provide a battery pack that can improve the technical problem of damaging the BMS module during thermal runaway of the existing battery pack.

[0006] The battery pack provided in this application includes:

[0007] a housing, wherein a receiving space is provided in the housing;

[0008] a battery module, the battery module being disposed in the accommodation space;

[0009] A BMS module is spaced apart from the battery module;

[0010] The isolation plate is arranged between the battery module and the BMS module and is sealed with the housing to isolate the battery module from the BMS module. Beneficial effects

[0011] In the battery pack provided in the present application, the battery pack includes a shell, a battery module and a BMS module. An isolation plate is arranged between the battery module and the BMS module and is sealed with the shell to achieve isolation between the BMS module and the battery module, thereby preventing the gas, jet, etc. generated by thermal runaway of the battery module from damaging the BMS module. BRIEF DESCRIPTION OF THE DRAWINGS

[0012] FIG1 is a schematic structural diagram of a battery pack provided in an embodiment of the present application;

[0013] FIG2 is an exploded schematic diagram 1 of a battery pack provided in an embodiment of the present application;

[0014] FIG3 is an exploded schematic diagram 2 of a battery pack provided in an embodiment of the present application;

[0015] FIG4 is an exploded schematic diagram 3 of a battery pack provided in an embodiment of the present application;

[0016] FIG5 is a top view 1 of a battery pack provided in an embodiment of the present application;

[0017] FIG6 is a cross-sectional view of the battery pack along line AA provided in the embodiment of FIG5 ;

[0018] FIG7 is a top view 2 of the battery pack provided in an embodiment of the present application.

[0019] Description of reference numerals:

[0020] 100. Battery pack;

[0021] 10. Shell; 101. Accommodation space; 11. Bottom wall; 12. Shell wall; 13. Shell opening; 14. Second connecting edge; 141. Gasket;

[0022] 20. Battery module; 21. Battery pack; 22. Busbar; 221. Main body; 222. Extension section; 2221. First extension section; 2222. Second extension section;

[0023] 30. BMS module; 31. Bar; 311. First bar; 312. Second bar; 313. First through hole; 314. Second through hole; 32. Control board; 33. Cover; 331. First connecting edge;

[0024] 40. Isolation plate; 41. First opening; 411. First inner wall; 412. First notch; 42. Second opening; 421. Second inner wall;

[0025] 50. Sealing ring;

[0026] 60. Fasteners;

[0027] 70. Connecting wire; 71. Connecting terminal; 72. Connector. Modes for Carrying Out the Invention

[0028] In the description of this application, unless otherwise specified or limited, the terms "connected," "connect," and "fixed" should be understood in a broad sense. For example, they can refer to fixed connections, detachable connections, or integration; mechanical connections or electrical connections; direct connections or indirect connections through an intermediate medium; and can refer to internal communication between two components or interaction between two components. Those skilled in the art will understand the specific meanings of the above terms in this application based on the specific circumstances.

[0029] In this application, unless otherwise expressly specified or limited, a first feature being "above" or "below" a second feature may include the first and second features being in direct contact, or the first and second features being in contact not directly but through another feature between them. Furthermore, a first feature being "above," "above," and "above" a second feature includes the first feature being directly above and obliquely above the second feature, with the first feature having a higher horizontal height than the second feature. A first feature being "below," "below," and "below" a second feature includes the first feature being directly below and obliquely below the second feature, with the first feature having a lower horizontal height than the second feature.

[0030] In the description of this embodiment, terms such as "upper," "lower," "left," "right," "front," and "rear" are used to refer to positions or locations based on the positions or locations shown in the accompanying drawings. These terms are intended to facilitate description and simplify operation, and are not intended to indicate or imply that the devices or components referred to must have, be constructed, or operate in a specific orientation. Therefore, they should not be construed as limitations on this application. Furthermore, the terms "first" and "second" are used for descriptive purposes only and do not have any special meanings.

[0031] The BMS (Battery Management System) plays a vital role in the health and safety of batteries. Failures in the BMS or problems with the batteries themselves can lead to thermal runaway, damaging the BMS. In related technologies, battery pack designs are often simple and highly integrated due to cost considerations and space constraints, resulting in deficiencies in thermal runaway protection.

[0032] Please refer to Figures 1-3. Figure 1 is a schematic diagram of the structure of the battery pack provided in an embodiment of the present application. Figure 2 is an exploded schematic diagram 1 of the battery pack provided in an embodiment of the present application. Figure 3 is an exploded schematic diagram 2 of the battery pack provided in an embodiment of the present application. The battery pack 100 includes a housing 10, a battery module 20, a BMS module 30, and an isolation plate 40. The housing 10 has a storage space 101, and the battery module 20 is disposed in the storage space 101. The battery module 20 is assembled from multiple battery cells. The BMS module 30 is spaced apart from the battery module 20. The BMS is used to intelligently manage and maintain the battery, monitor the battery status, prevent overcharging and over-discharging, and thus extend the battery life. The isolation plate 40 is disposed between the battery module 20 and the BMS module 30 and is sealed to the housing 10 to isolate the battery module 20 from the BMS module 30. The isolation plate 40 may be made of heat-resistant insulating plastic. On the one hand, the isolation plate 40 of the present application can block the high-temperature gas and high-temperature ejecta generated by thermal runaway from being ejected toward the BMS module 30, thereby isolating the flue gas from the BMS module 30. Since the isolation plate 40 is sealed, when the battery module 20 experiences thermal runaway, the high-temperature gas and high-temperature ejecta generated by the thermal runaway are prevented from being transferred to the BMS module 30 along the joint between the isolation plate 40 and the housing 10, so that the isolation plate 40 can block the impact from the thermal runaway, ensure that the BMS module 30 is not damaged, and avoid damage to the BMS system, so that the BMS module 30 can report a thermal runaway warning signal. On the other hand, the isolation plate 40 is firmly connected to the housing 10, which can separate the battery module 20 from the BMS module 30, isolate the heat and heat radiation generated by the operation of the BMS module 30, and prevent the lower battery from being heated, thereby achieving the effect of insulation and heat insulation. In addition, the BMS module 30 is set on the isolation plate 40, which can fix the BMS module 30 and prevent the BMS module 30 from detaching, thereby improving battery safety.

[0033] In some embodiments, the shell 10 includes a bottom wall 11 and a shell wall 12. The shell wall 12 is arranged around the bottom wall 11 to form a accommodating space 101. The end of the shell wall 12 away from the bottom wall 11 is provided with a shell opening 13 facing the BMS module 30. The isolation plate 40 is provided at the shell opening 13, and the periphery of the isolation plate 40 is sealed to the shell wall 12. Providing the isolation plate 40 at the shell opening 13 away from the bottom wall 11 can increase the space for the battery module 20 and avoid the BMS module 30 and the battery module 20 being too close. Specifically, the BMS module 30 is arranged at the top of the shell 10 and is independently arranged from the battery module 20. The shell wall 12 includes an end face facing the BMS module 30 and an inner side face facing the accommodating space 101. The end face is arranged around the shell opening 13. In some embodiments, the bottom periphery of the isolation plate 40 is sealed to the end surface, that is, the isolation plate 40 is entirely located outside the shell 10; in some embodiments, the side of the isolation plate 40 is sealed to the end of the inner side surface away from the bottom wall 11, that is, the isolation plate 40 is at least partially located in the accommodating space 101, and the top surface of the isolation plate 40 can be higher than the end surface or flush with the end surface, but not lower than the end surface.

[0034] In some embodiments, an explosion-proof valve is provided on the housing wall 12. If thermal runaway occurs in the battery module 20, electrolyte will be ejected outward from the explosion-proof valve. Since the BMS module 30 is located on top of the battery module 20 and is not in the direction of the electrolyte ejection, the BMS module 30 is prevented from being the first to be impacted. Assuming the BMS module 30 is intact, a thermal runaway alarm can be issued, allowing for timely detection of thermal runaway events in the battery module 20.

[0035] In some embodiments, the battery pack 100 further includes a sealant layer (not shown), which is sealed at the junction between the separator 40 and the shell wall 12. Specifically, the sealant layer can be applied to the periphery of the separator 40 or to the inner periphery of the shell wall 12. The sealant can be a liquid sealant, hot melt sealant, or paste sealant. Sealant has high stability and good adhesion, preventing the separator 40 from moving or falling off.

[0036] In some embodiments, the battery pack 100 further includes a sealing ring 50, which can be made of a flexible material such as rubber or silicone. The sealing ring 50 is sleeved over the isolation plate 40 and abuts between the housing wall 12 and the isolation plate 40. Specifically, the sealing ring 50 sleeves over the edge of the isolation plate 40, with the side of the sealing ring 50 facing away from the isolation plate 40 resting against the housing wall 12. For example, an annular groove can be provided within the sealing ring 50, and the periphery of the isolation plate 40 is mounted within the annular groove, tightly fitting the sealing ring 50.

[0037] In some embodiments, the battery pack 100 also includes a sealing tape, which can be arranged on the periphery of the isolation plate 40, and then the isolation plate 40 is adhered to the shell wall 12; the sealing tape can also be adhered to the inner periphery of the shell wall 12, and then the isolation plate 40 is aligned with the sealing tape and adhered to fix the isolation plate 40.

[0038] It is understandable that those skilled in the art may adopt other methods to seal the isolation plate 40 to the shell wall 12 , and this application does not limit this.

[0039] In some embodiments, the isolation plate 40 is not limited to the housing opening 13. The isolation plate 40 can be disposed within the accommodation space 101, dividing the accommodation space 101 into a first chamber and a second chamber. The BMS module 30 is disposed in the first chamber, and the battery module 20 is disposed in the second chamber. The periphery of the isolation plate 40 is sealed to the housing 10. Because the volume of the battery module 20 is smaller than that of the BMS module 30, the size of the first chamber can be smaller than that of the second chamber.

[0040] Specifically, the housing 10 has a square structure and includes a bottom wall 11 and a housing wall 12 surrounding the bottom wall 11. The housing wall 12 includes two opposing side walls and two end walls, with the side walls being longer than the end walls. The housing 10 also includes a top wall (not shown) that covers the housing wall 12 to seal the accommodating space 101. The isolation plate 40 includes two opposite long sides and two opposite short sides. In some embodiments, the isolation plate 40 is arranged parallel to the end wall, that is, the two short sides of the isolation plate 40 are respectively sealed and connected to the two side walls, one of the long sides is connected to the bottom wall 11, and one of the long sides is connected to the top wall, so that the periphery of the isolation plate 40 and the shell 10 are sealed and connected, and the first chamber and the second chamber are separated in the horizontal direction to separate the battery module 20 from the BMS module 30; in some embodiments, the isolation plate 40 is arranged parallel to the bottom wall 11, the two long sides are respectively sealed and connected to the two side walls, and the two short sides are respectively sealed and connected to the two end walls, so as to separate the first chamber and the second chamber in the vertical direction to separate the battery module 20 from the BMS module 30.

[0041] In some embodiments, the isolation plate 40 is provided with a first opening 41, and the battery pack 100 further includes a connecting wire 70, which is passed through the first opening 41. One end of the connecting wire 70 is connected to the battery module 20, and the other end of the connecting wire 70 is connected to the BMS module 30. Specifically, a bracket is provided in the accommodating space 101, and the battery module 20 includes a bus 22. The bus 22 is mounted on the bracket, and the connecting wire 70 is electrically connected to the bus 22. One end of the connecting wire 70 is connected to the bus 22, and the other end is connected to the BMS module 30. The connecting wire 70 includes a plurality of branch harnesses, and the end of the branch harnesses close to the BMS is fastened together by a connecting terminal 71. The BMS module 30 is provided with a connector 72, and the connecting terminal 71 is correspondingly connected to the connector 72 to transmit the collected signal to the BMS module 30 to control and manage the operation of the battery pack 100. The first opening 41 provided on the isolation plate 40 can facilitate the connection of the connecting wire 70 to the BMS module 20 , thereby reducing the length of the wire required for wiring and facilitating the wiring of the battery module 20 .

[0042] In some embodiments, the battery module 20 also includes a heat conducting plate, on which a temperature collection portion is provided. The heat conducting plate is electrically connected to the battery pack 100 through the bus 22. The connecting line 70 is passed through the first opening 41 and connected to the BMS module 30. The temperature information of the battery pack 100 can be transmitted to the BMS module 30 through the connecting line 70, so that the BMS module 30 can detect the temperature information of the battery pack 100 to avoid overheating of the battery pack 100.

[0043] In some embodiments, the isolation plate 40 includes a first inner wall 411 surrounding the first opening 41, and the connecting wire 70 is sealed and connected to the first inner wall 411. The sealed connection can prevent the high-temperature gas and high-temperature ejecta generated by thermal runaway from being transmitted to the BMS module 30 along the gap of the first opening 41, thereby increasing the safety of the BMS module 30. Specifically, the connection method between the connecting wire 70 and the first inner wall 411 can be a sealed connection between one end of the branch wiring harness close to the connecting terminal 71 and the first inner wall 411, or it can be a sealed connection between the connecting terminal 71 and the first inner wall 411. The size and shape of the first opening 41 can be set according to actual conditions to ensure that the connecting wire 70 can be passed through the first opening 41. It can be understood that when the number of connecting wires 70 increases, a plurality of first openings 41 can be set accordingly.

[0044] In some embodiments, the connection line 70 and the first inner wall 411 can be connected by a sealant, a sealing ring, a sealing tape, or the like, such as by gluing the sealant between the connection line 70 and the first inner wall 411. It is understood that those skilled in the art can adopt other methods to seal the connection line 70 to the first inner wall 411, and this application does not limit this.

[0045] In some embodiments, the isolation plate 40 includes a protrusion that protrudes toward the accommodation space 101 and forms a groove. The first inner wall 411 serves as the groove wall, and a sealing structure is disposed within the groove. A first notch 412, opposite the first opening 41, is disposed at the end of the protrusion away from the BMS module 30. The first notch 412 is smaller than the first opening 41 and serves to guide the connection cable 70 toward the BMS module 30. After passing through the first notch 412, the connection cable 70 extends to the first opening 41 and connects to the connector 72. The connection cable 70 can be sealed with the first notch 412 to enhance structural stability.

[0046] Please refer to Figures 4-6 in conjunction with Figure 3. Figure 4 is an exploded schematic diagram 3 of a battery pack provided in an embodiment of the present application. Figure 5 is a top view 1 of a battery pack provided in an embodiment of the present application with the BMS module retained. Figure 6 is a cross-sectional view of the battery pack along line AA provided in Figure 5. In some embodiments, the BMS module 30 further includes a tab 31 and a control board 32. The control board 32 is mounted on the side facing the battery module 20. The control board 32 is used to collect information from the battery module 20 and upload the information to a host computer, where the host computer is a computer that manages the integrated control board and corresponding control software. The tab 31 is connected to the side of the control board 32 facing the battery module 20 and is provided with a through hole. The battery module 20 includes a battery pack 21 and a bus 22 connected to the battery pack 21. The bus 22 is provided with vias corresponding to the through holes. The bus 22 is used to collect, distribute, and output current to ensure safe and efficient operation of the battery system. The battery pack 100 also includes a fastener 60. The separator 40 is provided with a second opening 42. The fastener 60 is inserted through the second opening 42, the through hole, and the via to secure the tab 31 and the bus 22. The connection between the tab 31 and the bus 22 allows the BMS module 30 to measure the voltage of the battery module 20 to monitor the battery status. The second opening 42 in the separator 40 facilitates the connection between the tab 31 and the bus 22, ensuring the stability and reliability of the battery pack 100 without changing the internal structure of the original battery pack 100.

[0047] Specifically, please refer to Figure 7, which is a top view 2 of the battery pack provided by an embodiment of the present application with the BMS module removed. The battery pack 21 includes a plurality of battery cells, and the busbar 22 includes a main body 221 and an extension 222. The busbar 22 can be a copper busbar, an aluminum busbar, or the like. The main body 221 includes a plurality of busbars, each of which has two ends electrically connected to the first electrode of the first battery cell and the second electrode of the second battery cell, respectively. The first battery cell and the second battery cell are two adjacent battery cells in the direction of series connection among the plurality of battery cells, and the first and second electrodes have opposite polarities. The third battery cell, the fourth battery cell, and so on are analogous. Since this is common knowledge in the art, this application will not elaborate on this. The busbar connected to the first battery cell is connected to the first extension 2221, and the busbar connected to the last battery cell is connected to the second extension 2222. The first extension 2221 and the second extension 2222 have opposite polarities.

[0048] The tab 31 is connected to the side of the control board 32 facing the battery pack 21. The tab 31 includes a first tab 311 and a second tab 312. The first tab 311 and the first extension 2221 have the same polarity, while the second tab 312 and the second extension 2222 have the same polarity. For example, the first tab 311 is the negative pole and is connected to the first extension 2221, which is also the negative pole. The second tab 312 is the positive pole and is connected to the second extension 2222, which is also the positive pole. The battery pack 100 also includes a plurality of fasteners 60, which can be screws, bolts, studs, etc. The busbar 22 and tab 31 connected using fasteners 60 are easy to install and disassemble, and the connection is more reliable and stable. Specifically, there are at least two second openings 42, and each fastener 60 is provided through one second opening 42. The second opening 42 is provided on one side of the isolation plate 40 and is spaced apart from the first opening 41. The size and shape of the second opening 42 can be set according to actual conditions to ensure that the fastener 60 can be inserted into the second opening 42. Specifically, the first tab 311 defines a first through hole 313, the first extension section 2221 defines a first via hole, the first tab 311 is attached to the first extension section 2221, and a fastener 60 is inserted through the first through hole 313 and the first via hole to secure the first tab 311 and the first extension section 2221. The second tab 312 defines a second through hole 314, the second extension section 2222 defines a second via hole, the second tab 312 is attached to the second extension section 2222, and a fastener 60 is inserted through the second through hole 314 and the second via hole to secure the second tab 312 and the second extension section 2222.

[0049] In some embodiments, the isolation plate 40 includes a second inner wall 421 surrounding the second opening 42, with a fastener 60 sealingly connected to the second inner wall 421. This sealed connection prevents high-temperature gases and high-temperature ejecta generated by thermal runaway from being transmitted through the gap in the second opening 42 to the BMS module 30, thereby enhancing the safety of the BMS module 30. Specifically, one fastener 60 secures the first extension 2221 and the first tab 311, then seals the fastener 60 to the second inner wall 421 via a sealing structure. Another fastener 60 secures the second extension 2222 and the second tab 312, then seals the fastener 60 to the second inner wall 421 via a sealing structure. The fastener 60 and the second inner wall 421 can be connected using a sealant, a sealing ring, or a sealing tape, such as a sealant bonded between the fastener 60 and the second inner wall 421. It is understood that those skilled in the art may employ other methods to achieve a sealing connection between the fastener 60 and the second inner wall 421, and this application is not limited thereto.

[0050] Please continue to refer to Figures 6 and 7. Figure 6 is a cross-sectional view of the battery pack provided in an embodiment of the present application along AA. Figure 7 is a top view 2 of the battery pack provided in an embodiment of the present application. In some embodiments, the BMS module 30 includes a cover body 33, the cover body 33 includes a first connecting edge 331 facing the shell 10, the shell 10 includes a bottom wall 11 and a shell wall 12 surrounding the bottom wall 11, the shell wall 12 also includes a second connecting edge 14 facing the cover body 33, and the second connecting edge 14 is arranged around the isolation plate 40. Specifically, the shell wall 12 includes an end face facing the BMS module 30, the second connecting edge 14 is connected to the periphery of the end face, when the isolation plate 40 is arranged at the shell opening 13, the isolation plate 40 and the first connecting edge 331 are located in the same plane, and when the isolation plate 40 is arranged in the accommodating space 101, the isolation plate 40 is arranged below the first connecting edge 331. The first connecting edge 331 and the second connecting edge 14 are adapted to each other. When the cover 33 is placed on the housing 10, the first connecting edge 331 and the second connecting edge 14 are sealed. The first connecting edge 331 and the second connecting edge 14 can be fastened around the housing 10 by screws, bolts, or other fastening structures. Those skilled in the art can also use plug-in, snap-on, or other methods to connect the cover 33 and the housing 10, which is not limited in this application.

[0051] In some embodiments, the shell 10 also includes a gasket 141, a groove is provided in the second connecting edge 14, and the gasket 141 is disposed in the groove. The cover body 33 includes a protrusion, which is connected to the first connecting edge 331 and protrudes toward the shell 10. When the cover body 33 is covered on the shell 10, the protrusion is embedded in the gasket 141 to increase the sealing effect of the cover body 33 and the shell 10.

Claims

1. A battery pack (100), comprising: A housing (10), wherein a receiving space (101) is provided in the housing (10); a battery module (20), the battery module (20) being disposed in the accommodating space (101); A BMS module (30) is spaced apart from the battery module (20); The isolation plate (40) is disposed between the battery module (20) and the BMS module (30) and is sealed and connected to the housing (10) to isolate the battery module (20) and the BMS module (30).

2. The battery pack (100) according to claim 1, wherein: The shell (10) comprises a bottom wall (11) and a shell wall (12), wherein the shell wall (12) is arranged around the periphery of the bottom wall (11) to form the accommodating space (101), and an opening of the shell (10) is provided at one end of the shell wall (12) away from the bottom wall (11), and the isolation plate (40) is arranged at the opening of the shell (10), and the periphery of the isolation plate (40) is sealed and connected to the shell wall (12).

3. The battery pack (100) according to claim 2, further comprising a sealant layer, wherein the sealant layer is sealed and connected to a connection between the isolation plate (40) and the shell wall (12).

4. The battery pack (100) according to claim 2, further comprising a sealing ring (50), wherein the sealing ring (50) is sleeved on the isolation plate (40) and abuts between the shell wall (12) and the isolation plate (40).

5. The battery pack (100) according to claim 1, wherein: The isolation plate (40) is arranged in the accommodating space (101) and divides the accommodating space (101) into a first chamber and a second chamber. The BMS module (30) is arranged in the first chamber, and the battery module (20) is arranged in the second chamber. The periphery of the isolation plate (40) is sealed and connected to the shell (10).

6. The battery pack (100) according to any one of claims 1 to 5, wherein: The isolation plate (40) is provided with a first opening (41), and the battery pack (100) further includes a connecting wire (70), the connecting wire (70) being passed through the first opening (41), one end of the connecting wire (70) being connected to the battery module (20), and the other end of the connecting wire (70) being connected to the BMS module (30).

7. The battery pack (100) according to claim 6, wherein: The isolation plate (40) comprises a first inner wall (411) surrounding the first opening (41), and the connecting line (70) is sealedly connected to the first inner wall (411).

8. The battery pack (100) according to any one of claims 1 to 5, wherein the BMS module (30) comprises a tab (31) and a control board (32), wherein the tab (31) is connected to a side of the control board (32) facing the battery module (20), and the tab (31) is provided with a through hole; The battery module (20) includes a battery pack (21) and a busbar (22) connected to the battery pack (21), wherein the busbar (22) is provided with a via hole corresponding to the through hole; The battery pack (100) further includes a fastener (60), the isolation plate (40) is provided with a second opening (42), and the fastener (60) is passed through the second opening (42), the through hole and the via hole to fix the tab (31) and the busbar (22).

9. The battery pack (100) according to claim 8, wherein: The isolation plate (40) includes a second inner wall (421) surrounding the second opening (42), and the fastener (60) is sealedly connected to the second inner wall (421).

10. The battery pack (100) according to claim 1, wherein the BMS module (30) includes a cover (33), the cover (33) includes a first connecting edge (331) facing the shell (10), the shell (10) includes a bottom wall (11) and a shell wall (12) surrounding the bottom wall (11), the shell wall (12) includes a second connecting edge (14) facing the cover (33), the second connecting edge (14) is arranged around the isolation plate (40), and the first connecting edge (331) and the second connecting edge (14) are sealed and connected.

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