Integrated battery pack and electric vehicle

Abstract

Provided in the present application are an integrated battery pack and an electric vehicle. The integrated battery pack comprises: a case (1), a battery module (2) and a liquid cooling plate (3), wherein an accommodating cavity (110) is provided inside the case (1), the battery module (2) is arranged in the accommodating cavity (110), and the liquid cooling plate (3) is arranged below the battery module (2). A pressure relief valve (22) is provided at the bottom of the battery module (2), the side surface of the battery module (2) provided with the pressure relief valve (22) abutting against the liquid cooling plate (3). A pressure relief channel (33) is provided in the liquid cooling plate (3), the side surface of the liquid cooling plate (3) facing the battery module (2) being provided with a pressure relief hole (30) in communication with the pressure relief channel (33), the pressure relief hole (30) facing the pressure relief valve (22). High-temperature gases and other substances discharged by a battery cell during pressure relief may be kept away from the top of the case, thereby reducing the thermal impact of high-temperature substances on an occupant compartment. The high-temperature gases discharged during pressure relief can also be rapidly cooled during the movement in the pressure relief channel, thereby reducing the temperature in the whole case, and effectively reducing the thermal impact of the case on the occupant compartment, improving the thermal safety of the occupant compartment.

Description

Integrated battery packs and electric vehicles

[0001] This application claims priority to the Chinese patent application filed with the China Patent Office on August 6, 2024, with application number 202421894953.2. The entire contents of the above application are incorporated by reference into this application.

[0002] Technical Field

[0003] The present application relates to the field of battery manufacturing technology, for example, to an integrated battery pack and an electric vehicle.

[0004] Background Art

[0005] With the rapid development and technological iteration of new energy vehicles, the industry has placed higher demands on vehicle lightweighting, safety, and manufacturing costs. To this end, Cell-to-Body (CTB) technology has emerged. Through integrated vehicle design, it meets market demands for fewer parts and lower vehicle manufacturing costs.

[0006] A CTB electric vehicle in related technology integrates the chassis of the entire vehicle with the box of the battery pack, thereby greatly simplifying the structure of the entire vehicle.

[0007] Technical issues

[0008] Since the top of the battery pack box forms the bottom of the vehicle's passenger compartment, when the battery module in the battery pack experiences thermal runaway, the high-temperature material discharged from the pressure relief valve spreads to the bottom of the passenger compartment, directly causing thermal impact on the passenger compartment and making it impossible to guarantee the thermal safety of the passenger compartment.

[0009] Technical Solutions

[0010] An integrated battery pack provided in the present application includes a box body, a battery module and a liquid cooling plate. The box body has a accommodating cavity, the battery module is arranged in the accommodating cavity, the liquid cooling plate is arranged below the battery module, a pressure relief valve is formed at the bottom of the battery module, one side of the battery module having the pressure relief valve abuts against the liquid cooling plate, a pressure relief channel is formed in the liquid cooling plate, and a pressure relief hole connected to the pressure relief channel is opened on one side of the liquid cooling plate facing the battery module, and the pressure relief hole faces the pressure relief valve.

[0011] The present application also provides an electric vehicle, comprising a vehicle body, seats and an integrated battery pack, wherein the integrated battery pack is arranged on the vehicle body and the seats are installed on the top of the box of the integrated battery pack.

[0012] Beneficial effects

[0013] Beneficial effects of this application:

[0014] By placing the pressure relief valve at the bottom of the battery module, high-temperature gases and other substances emitted during pressure relief from the individual cells are directed away from the top of the chassis, reducing the thermal impact of these substances on the passenger compartment. Furthermore, because the pressure relief channel for conveying high-temperature substances is located on the liquid cooling plate, the high-temperature gases discharged during pressure relief can also be rapidly cooled during their movement within the pressure relief channel, thereby lowering the temperature of the entire chassis, effectively reducing the thermal impact on the passenger compartment from the chassis and improving the thermal safety performance of the passenger compartment.

[0015] BRIEF DESCRIPTION OF THE DRAWINGS

[0016] FIG1 is an exploded view of an integrated battery pack provided in some implementations of the present application.

[0017] FIG2 is a top view of an integrated battery pack provided in some implementations of the present application.

[0018] FIG3 is a schematic diagram of a battery module and a liquid cooling plate provided in some implementations of the present application.

[0019] FIG4 is a partial cross-sectional view of a battery module provided by some implementations of the present application.

[0020] FIG5 is a partial cross-sectional view of an integrated battery pack provided by some implementations of the present application.

[0021] FIG6 is an enlarged view of point A in FIG5 .

[0022] FIG7 is a schematic diagram of the entire vehicle structure provided by some implementations of the present application.

[0023] In the picture:

[0024] 1. Box body; 11. Box bottom; 110. Accommodation cavity; 111. Bottom plate; 112. Side plate; 113. Side beam; 12. Box cover; 13. Mounting bracket;

[0025] 2. Battery module; 21. Single cell; 22. Pressure relief valve; 23. Terminal; 24. CCS assembly; 25. Insulation sheet;

[0026] 3. Liquid cooling plate; 30. Pressure relief hole; 31. First plate; 32. Second plate; 33. Pressure relief channel; 34. Liquid cooling channel;

[0027] 4. Layering; 41. Support plate;

[0028] 5. Bottom guard plate;

[0029] 6. BDU electrical components; 61. Copper busbar;

[0030] 7. First buffer layer; 8. Second buffer layer; 9. Mounting slot; 10. Vehicle body; 14. Seat; 15. Integrated battery pack.

[0031] Modes for Carrying Out the Invention

[0032] The technical solution of this application is explained below with reference to the accompanying drawings and through specific implementation methods.

[0033] As shown in Figures 1, 5, and 6, the present application provides an integrated battery pack comprising a housing 1, a battery module 2, and a liquid cooling plate 3. The housing 1 is a rectangular parallelepiped, with its length extending in the X direction, its width in the Y direction, and its height in the Z direction. The housing 1 is hollow and defines a receiving cavity 110. The battery module 2 and the liquid cooling plate 3 are both mounted within the receiving cavity 110, with the liquid cooling plate 3 positioned below the battery module 2. For example, the liquid cooling plate 3 is positioned at the bottom of the housing 1, i.e., the liquid cooling plate 3 is located at the bottom of the receiving cavity 110. The battery module 2 includes a plurality of battery cells 21. Each battery cell 21 has two terminals 23 at one end, one positive terminal and one negative terminal. A pressure relief valve 22 is provided at the end of the battery cell 21 facing away from the terminals 23. When thermal runaway occurs in the battery module 2, the pressure relief valve 22 opens to release high-temperature gases and other substances (e.g., electrolyte) within the battery cell 21. The orientation described in this embodiment is based on the integrated battery pack being installed in an electric vehicle, with the pressure relief valve 22 located at the bottom of the battery module 2 and the terminal 23 at the top. The battery module 2 is mounted on a liquid cooling plate 3. The side of the battery module 2 with the pressure relief valve 22 (i.e., the bottom of the battery module 2) abuts the liquid cooling plate 3, enabling heat exchange between the liquid cooling plate 3 and the battery module 2, thereby cooling the battery module 2. A pressure relief channel 33 is formed within the liquid cooling plate 3. Pressure relief holes 30 are provided on the side of the liquid cooling plate 3 facing the battery module 2, communicating with the pressure relief channel 33. The number and location of the pressure relief holes 30 correspond to the number and location of the pressure relief valves 22 in the battery module 2. Each pressure relief hole 30 faces the corresponding pressure relief valve 22. When thermal runaway occurs in the battery module 2, high-temperature gases and other substances are discharged sequentially through the pressure relief valve 22 and the pressure relief hole 30 into the pressure relief channel 33, and are ultimately transported along the pressure relief channel 33 to the exterior of the housing 1.

[0034] It is understandable that the integrated battery pack is installed on the body of the electric vehicle, and the top of the box body 1 forms the bottom of the passenger compartment, so as to realize the integrated design of the vehicle chassis and the integrated battery pack. Since the pressure relief valve 22 is located at the bottom of the battery module 2, the high-temperature gas and other substances discharged when the single battery 21 is depressurized can be kept away from the top of the box body 1, so as to reduce the thermal impact of the high-temperature substances on the passenger compartment. In addition, since the pressure relief channel 33 configured to transport high-temperature substances is provided on the liquid cooling plate 3, the high-temperature gas discharged during pressure relief can also be quickly cooled during the movement in the pressure relief channel 33, thereby reducing the temperature inside the entire box body 1, and effectively reducing the thermal impact of the box body 1 on the passenger compartment.

[0035] The box body 1 includes a box bottom 11 and a box cover 12. The box bottom 11 includes a bottom plate 111, four side plates 112, and side beams 113. The bottom plate 111 is a square flat plate, and the four side plates 112 are arranged around the bottom plate 111, so that a storage cavity 110 is formed between the bottom plate 111 and the four side plates 112. The two side plates 112 facing each other in the Y direction are arranged in an "L" shape, that is, the side plates 112 include vertical plates and horizontal plates arranged vertically, and the free ends of the horizontal plates extend in a direction away from the storage cavity 110. There are multiple side beams 113, and the multiple side beams 113 are arranged at intervals on the "L"-shaped side plates 112, that is, the side beams 113 are connected and fixed to both the vertical plates and the horizontal plates. The side beams 113 are manufactured through a rolling process and are used to strengthen the structural strength of the box body 1 and prevent the box body 1 from deforming when it is hit from the side. The box cover 12 is placed on the top of the box bottom 11 to form a storage cavity 110 between the box cover 12 and the box bottom 11. A mounting bracket 13 is provided on one side of the box cover 12 facing away from the box bottom 11. The mounting bracket 13 is provided for mounting a seat. The box cover 12 and the box bottom 11 are fixed by bolts, screws, rivets, welding, etc.

[0036] Optionally, the integrated battery pack further includes a bottom guard plate 5, which is sandwiched between the bottom of the accommodating cavity 110 and the liquid cooling plate 3. The bottom guard plate 5 protects the liquid cooling plate 3, preventing damage to the liquid cooling plate 3 caused by impact on the bottom plate 111 of the box body 1 when the electric vehicle hits the bottom.

[0037] Optionally, the integrated battery pack further includes a battery disconnect unit (BDU) electrical component 6. The BDU electrical component 6 can be an electrical component known in the related art. The BDU electrical component 6 is configured for high-voltage power distribution and is electrically connected to the battery module 2.

[0038] 1 and 3 , there are four battery modules 2, and the four battery modules 2 are distributed in a rectangular array. In some embodiments, the number and distribution of the battery modules 2 can be flexibly selected according to the specific internal structure and storage capacity of the integrated battery pack. The battery module 2 includes a plurality of battery packs arranged in sequence along a first direction (the Y direction in the figure), and each battery pack includes a plurality of single cells 21 arranged in sequence along a second direction (the X direction in the figure). In this embodiment, each battery module 2 includes four battery packs. The single cell 21 is a square battery, and the top of the single cell 21 has a positive electrode column and a negative electrode column. In the same battery pack, all the positive electrode columns are arranged in a row along the length direction of the box body 1, and all the negative electrode columns are arranged in a row along the length direction of the box body 1.

[0039] The battery module 2 also includes a CCS assembly 24 and an insulating sheet 25. The integrated busbar (CCS) assembly 24 is connected to the pole 23 of the single cell 21 and is configured to collect voltage, temperature, and other data from the single cell 21. The CCS assembly 24 is located on top of the battery module 2, and the insulating sheet 25 covers the CCS assembly 24 to provide insulation protection. The BDU electrical assembly 6 includes a copper busbar 61, the length of which extends along the length of the box 1. The four battery modules 2 are arranged in groups of two on either side of the copper busbar 61, so that the corresponding CCS assemblies 24 on the four battery modules 2 can be connected to the copper busbar 61.

[0040] As shown in Figures 3, 5, and 6, the pressure relief holes 30 of the liquid cooling plate 3 are covered with mica sheets (not shown). The mica sheets are configured to selectively block the pressure relief holes 30. The mica sheets provide thermal insulation and isolation, preventing high-temperature gases discharged into the pressure relief channel 33 from passing through the surrounding pressure relief holes 30 and causing thermal contamination to other cells 21 when a cell 21 releases pressure. When a cell 21 releases pressure, the high-temperature, high-pressure gas can break through the mica sheets and enter the pressure relief channel 33 through the pressure relief holes 30.

[0041] The liquid cooling plate 3 is formed with multiple liquid cooling channels 34 spaced along a first direction (direction Y in the figure). The pressure relief channel 33 is located between two adjacent liquid cooling channels 34. The liquid cooling plate 3 comprises a first plate 31 and a second plate 32, which are stacked. The second plate 32 has multiple grooves formed on the side facing the battery module 2. These grooves are spaced along the first direction, with each groove extending along the length of the housing 1. The first plate 31 is positioned on the side of the second plate 32 facing the battery module 2. The first plate 31 covers the notches of the grooves, sealing them and keeping them closed. A portion of the grooves encloses the pressure relief channel 33 with the first plate 31, located directly below the pressure relief valve 22 of the battery module 2. Another portion of the grooves encloses the liquid cooling channel 34 with the first plate 31. Pressure relief holes 30 are provided on the first plate 31, located above the pressure relief channel 33. Correspondingly, a pressure relief port is also provided on the side wall of the box body 1, and the pressure relief channel 33 on the liquid cooling plate 3 is connected to the pressure relief port so that the high-temperature gas and gaseous substances can be discharged to the outside of the box body 1 through the pressure relief port during pressure relief. In addition, the liquid cooling plate 3 is also provided with a liquid inlet and a liquid outlet connected to the liquid cooling channel 34. The liquid inlet and the liquid outlet are respectively connected to the external coolant storage tank to realize the circulation of liquid coolant between the liquid cooling plate 3 and the coolant storage tank. In this embodiment, by arranging the pressure relief channel 33 between adjacent liquid cooling channels 34, it is beneficial to utilize the liquid cooling channel 34 to quickly absorb the heat of the high-temperature substance in the pressure relief channel 33, thereby playing a role in quickly cooling the integrated battery pack. In order to facilitate the processing and manufacturing of the second plate 32, the second plate 32 is bent back and forth along the first direction, that is, the cross-section of the second plate 32 is "S"-shaped, so that a plurality of spaced grooves are formed on one side of the second plate 32.

[0042] As shown in Figures 3 and 4 , the top of the battery module 2 is interspersed with multiple beadings 4. The opposing ends of the beadings 4 are bonded to the battery module 2 and the inner wall of the case 1, respectively. The beadings 4 are elongated, columnar structures that extend along the length of the case 1. Multiple beadings 4 are spaced parallel and spaced apart across the width of the case 1. The beadings 4 support the case lid 12. When pressure from the seat and occupants is applied to the case lid 12, the pressure is evenly distributed across the housings of the multiple battery cells 21 through the beadings 4. This prevents deformation of the top of the case 1 from concentrated stress and prevents direct pressure from the case lid 12 on the battery cell terminals 23, potentially causing circuit failure. The opposing ends of the beadings 4 are bonded to the battery module 2 and the inner wall of the case 1, respectively. Specifically, the top of the beadings 4 is bonded to the inner wall of the case lid 12 with structural adhesive, while the bottom of the beadings 4 is secured to the battery module 2.

[0043] A plurality of battery modules 2 are installed in the box body 1. In this embodiment, the number of battery modules 2 is four. The four battery modules 2 are divided into two groups, and the two groups of battery modules 2 are spaced apart along the first direction so that the copper busbar 61 of the BDU electrical component 6 can be installed between the two groups of battery modules 2. This structure not only facilitates the connection between the copper busbar 61 and the battery module 2, but also saves space. Along the first direction, a support plate 41 is provided between two adjacent battery modules 2, and the two ends of the support plate 41 are respectively connected to the pressure strips 4 on the two adjacent battery modules 2, and a mounting groove 9 is formed between the support plate 41 and the two pressure strips 4. The copper busbar 61 is installed in the mounting groove 9. In another embodiment, the support plate 41 and the pressure strip 4 can be an integrally formed structure.

[0044] As shown in Figure 5, the sidewalls of the box body 1 are hollow. Since the corresponding area of ​​the accommodating cavity 110 is primarily located on the box bottom 11, the sidewalls of the box bottom 11 are hollow. The sidewalls of the box bottom 11 are filled with a first buffer layer 7. This first buffer layer 7 is made of foam and acts as a buffer and energy absorber. When the sidewalls of the box body 1 are impacted by external forces, the first buffer layer 7 provides protection and cushioning, preventing damage to the battery modules 2 within the box body 1.

[0045] Optionally, a second buffer layer 8 is placed between the battery module 2 and the inner wall of the box 1. Since the area corresponding to the accommodating cavity 110 primarily exists on the box bottom 11, the second buffer layer 8 is positioned between the inner wall of the box bottom 11 and the battery module 2. The second buffer layer 8 is made of foam and acts as a buffer and energy absorber. When the sidewalls of the box 1 are impacted by external forces, the second buffer layer 8 provides protection and cushioning, preventing damage to the battery module 2 within the box 1.

[0046] In the battery module 2, adjacent cells 21 are bonded together using structural adhesive. Filling with structural adhesive eliminates gaps between adjacent cells 21, allowing all cells 21 to form a single unit, thereby increasing the structural strength of the entire battery module 2 and allowing the entire module 2 to withstand pressure from the cover 12.

[0047] As shown in Figures 1, 2 and 7, an electric vehicle is also provided, comprising a vehicle body 10, a seat 14 and an integrated battery pack 15. The integrated battery pack 15 is mounted on the vehicle body 10, and the top of the housing 1 of the integrated battery pack 15 (i.e., the housing cover 12) also serves as the bottom of the passenger compartment of the vehicle body 10, thereby simplifying the overall vehicle structure. The seat 14 is mounted on a mounting bracket 13 on the housing cover 12. Since the pressure relief valve 22 of the battery module 2 is located at the bottom of the housing 1, the high-temperature gas discharged when the single cell 21 is depressurized is discharged from the bottom area of ​​the housing 1, reducing the thermal impact of the high-temperature gas on the top area of ​​the housing 1, thereby reducing the thermal impact of the interior of the housing 1 on the passenger compartment, and improving the thermal safety performance of the passenger compartment.

[0048] In this embodiment, by positioning the pressure relief valve 22 at the bottom of the battery module 2, the high-temperature gases and other substances discharged during pressure relief from the single cells 21 are directed away from the top of the chassis 1, thereby reducing the thermal impact of these substances on the passenger compartment. Furthermore, since the pressure relief channel 33, which is configured to convey high-temperature substances, is located on the liquid cooling plate 3, the high-temperature gases discharged during pressure relief can also be rapidly cooled during their movement within the pressure relief channel 33, thereby lowering the temperature within the entire chassis 1. This effectively reduces the thermal impact on the passenger compartment from the chassis 1 and improves the thermal safety of the passenger compartment.

Claims

1. An integrated battery pack, comprising a box, a battery module and a liquid cooling plate, wherein the box has a accommodating cavity, the battery module is arranged in the accommodating cavity, the liquid cooling plate is arranged below the battery module, a pressure relief valve is formed at the bottom of the battery module, a side of the battery module having the pressure relief valve abuts against the liquid cooling plate, a pressure relief channel is formed in the liquid cooling plate, a side of the liquid cooling plate facing the battery module is provided with a pressure relief hole connected to the pressure relief channel, and the pressure relief hole faces the pressure relief valve.

2. The integrated battery pack according to claim 1, wherein: The liquid cooling plate is arranged at the bottom of the box body.

3. The integrated battery pack according to claim 1, wherein: The pressure relief hole is covered with a mica sheet, and the mica sheet is configured to selectively block the pressure relief hole.

4. The integrated battery pack according to claim 1, wherein: A plurality of liquid cooling channels spaced apart along a first direction are formed in the liquid cooling plate, and the pressure relief channel is located between two adjacent liquid cooling channels.

5. The integrated battery pack according to claim 4, wherein: The liquid cooling plate includes a first plate and a second plate which are stacked, a side of the second plate facing the battery module having a plurality of grooves spaced apart along the first direction, the first plate being arranged on a side of the second plate facing the battery module, and the first plate being capable of blocking the notches of the grooves, some of the plurality of grooves forming the pressure relief channel with the first plate, and another part of the grooves forming the liquid cooling channel with the first plate, and the pressure relief hole being provided on the first plate.

6. The integrated battery pack according to any one of claims 1 to 5, wherein: A plurality of pressure strips are arranged at intervals on the top of the battery module, and opposite ends of the pressure strips are respectively connected to the battery module and the inner wall of the box body.

7. The integrated battery pack according to any one of claims 1 to 5, wherein: The battery module includes a plurality of battery packs arranged in sequence along a first direction, each of the battery packs includes a plurality of single cells arranged in sequence along a second direction, the first direction is perpendicular to the second direction, and adjacent single cells are bonded and fixed by structural adhesive.

8. The integrated battery pack according to any one of claims 1 to 5, wherein: The side wall of the box body is a hollow structure, and the side wall of the box body is filled with a first buffer layer.

9. The integrated battery pack according to any one of claims 1 to 5, wherein: A second buffer layer is filled between the battery module and the inner wall of the box.

10. The integrated battery pack according to any one of claims 1 to 5, further comprising a bottom guard plate, wherein the bottom guard plate is sandwiched between the bottom of the accommodating cavity and the liquid cooling plate.

11. An electric vehicle, comprising a vehicle body, a seat and an integrated battery pack as claimed in any one of claims 1 to 10, wherein the integrated battery pack is arranged on the vehicle body, and the seat is installed on the top of the box of the integrated battery pack.

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