Battery module and electric equipment with same

Abstract

The invention relates to the technical field of batteries, and provides a battery module and electric equipment with the same. The battery module comprises a plurality of soft package batteries and a fixed end plate. The plurality of soft package batteries comprise shells and battery cells, extend in a first direction and are stacked in a second direction, each shell comprises two shell parts, at least one shell part is provided with a concave part and an edge sealing part located on at least part of the periphery of the concave part, and the concave part and the other shell part define a containing cavity; the edge sealing part and the shell part opposite to the edge sealing part are bonded in a sealing manner so as to seal an accommodating cavity for accommodating the battery cell; the edge sealing part comprises a first edge sealing part for sealing the accommodating cavity in a first direction; the fixing end plate and the first edge sealing part are located on the same side of the soft package batteries in the height direction and provided with exhaust holes, the first direction, the second direction and the height direction are perpendicular in pairs, the sealing width of the first edge sealing part is d, in the first direction, the size of the fixing end plate is L, the size of the exhaust holes is L1, and d1L1 / L is larger than or equal to 0.3 and smaller than or equal to 8.4.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of batteries, in particular, to a battery module and a power consumption device with the same. BACKGROUND

[0002] In recent years, with the rapid development of new energy vehicles, energy storage systems and other fields, high-performance batteries represented by lithium-ion batteries have significant advantages such as high energy density and long cycle life. However, under abnormal working conditions such as overcharging, soft package batteries may cause thermal runaway, which threatens the safety of the battery.

[0003] When a sharp exothermic reaction occurs inside the soft package battery, a large amount of high-temperature gas and heat will be generated in the process of electrolyte decomposition and electrode material reaction, causing the internal pressure of the battery to increase sharply. Once the internal pressure exceeds the bearing limit of the shell, the high-temperature gas will burst through the seal at the thinnest edge of the structure, causing the shell seal to fail. At this time, the high-temperature gas will be instantly ejected to the outside space of the battery, and a large amount of heat will be rapidly transferred to the adjacent battery during the release process, causing a strong thermal shock, which may cause thermal runaway to spread throughout the battery module. SUMMARY

[0004] Therefore, the present application provides a battery module and a power consumption device with the same, aiming to improve the safety and reliability of the battery module as a whole.

[0005] In a first aspect, the battery module provided by the present application comprises a plurality of soft package batteries and a fixed end plate.

[0006] The plurality of soft package batteries extend along a first direction and are stacked along a second direction, the first direction being perpendicular to the second direction. The soft package battery comprises a shell and an electrode core. The shell comprises two shell parts, at least one of which is provided with a recess and an edge part located at least part of the outer periphery of the recess. The recess and the other shell part enclose a containing cavity. The edge part and the shell part opposite to it are sealingly bonded to close the containing cavity. The containing cavity contains the electrode core. The edge part comprises a first edge part sealing the containing cavity in the first direction. The fixed end plate is located on the same side of the plurality of soft package batteries in the height direction as the first edge part. The first direction, the second direction and the height direction are perpendicular to each other. The fixed end plate is provided with an exhaust hole. The sealing width of the first edge part is d, in mm. In the first direction, the size of the fixed end plate is L, in mm, and the size of the exhaust hole is L, in mm. 0.3≤d L1 / L≤8.4.

[0007] In a second aspect, the power consumption device provided by the present application comprises the battery module of the first aspect.

[0008] The battery module provided by the present application has the following advantages: d1 Limiting L1 / L within the aforementioned range ensures that the vent provides sufficient outlet channels for the high-temperature gas released from the first sealing edge, reducing the residence time of the high-temperature gas inside the module and preventing the accumulation of high-temperature gas released during thermal runaway of the pouch battery inside the battery module, thereby reducing the risk of thermal shock to adjacent pouch batteries. At the same time, it does not excessively weaken the structural strength of the fixed end plate, reducing the possibility of deformation or even structural failure under mechanical load, thus helping to improve the structural stability and safety performance of the battery module. Attached Figure Description

[0009] To more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings used in the embodiments will be briefly described below.

[0010] It should be understood that the following figures only illustrate certain embodiments of the invention and should not be construed as limiting the scope.

[0011] It should also be understood that the same or similar reference numerals are used in the accompanying drawings to denote the same or similar elements.

[0012] It should also be understood that the accompanying drawings are only schematic, and the dimensions and scales of the elements in the drawings are not necessarily precise.

[0013] Figure 1 This is a schematic diagram of the structure of a battery module according to an embodiment of the present invention.

[0014] Figure 2 yes Figure 1 An exploded view of the battery module.

[0015] Figure 3 yes Figure 1 A top view of the battery module.

[0016] Figure 4 yes Figure 2 A schematic diagram of the structure of the soft-pack battery in the battery module.

[0017] Figure 5 yes Figure 4 An exploded view of the pouch cell in the diagram.

[0018] Figure 6 yes Figure 5 A schematic diagram of a portion of the pouch cell.

[0019] Figure 7 yes Figure 5 A schematic diagram of a portion of the pouch cell.

[0020] Figure 8 yes Figure 2 A schematic diagram of a portion of the battery module.

[0021] Figure 9 is Figure 2 a sectional view of a part of the battery module in

[0022] Figure 10 is Figure 9 a close-up view of a part of the battery module in

[0023] Figure 11 is a structural schematic view of a part of a soft-pack battery of a battery module according to a variant of the present application.

[0024] Figure 12 is a structural schematic view of an electrical device according to an embodiment of the present application.

[0025] BRIEF DESCRIPTION OF DRAWINGS: soft-pack battery - 100; housing - 10; housing part - 101; recess - 11; edge sealing part - 12; first edge sealing part - 121; first section - 1211; second section - 1212; second section - 1213; accommodating cavity - 13; cell - 20; fixed end plate - 30; flat part - 301; recessed part - 302; exhaust hole - 31; side plate - 32; spacer - 40; adhesive - 50; first adhesive area - 51; second adhesive area - 52; battery module - 200; electrical device - 300. DETAILED DESCRIPTION

[0026] Embodiments of the present application are described herein with reference to the drawings. It should be understood that the implementations of the present application can vary as

[0027] <Example soft-pack battery> With reference to Figure 4 and Figure 5 , the soft-pack battery 100 provided by the embodiments of the present application includes a cell 20 and a housing 10.

[0028] The cell 20 is a component in which electrochemical reactions occur, and is also the smallest unit in the soft-pack battery 100 that can perform electrochemical reactions such as charging or discharging. The cell 20 generally includes a positive electrode sheet, a negative electrode sheet, and a separator. As an example, the cell 20 can be a lithium-ion cell 20 that operates by lithium ions moving between the positive electrode sheet and the negative electrode sheet.

[0029] It can be understood that the cell 20 has various implementations, for example, the cell 20 can be a cylindrical cell 20 formed by winding a positive electrode sheet, a separator, and a negative electrode sheet, and for another example, the cell 20 can be a cell 20 having a substantially cuboid shape formed by winding or stacking a positive electrode sheet, a separator, and a negative electrode sheet.

[0030] The shell 10 is used to provide a containing cavity 13 to accommodate the battery cell 20 and other components therein and to isolate them from the outside. The containing cavity 13 can be obtained by stamping. In the current embodiment, the shell 10 comprises two shell parts 101, each of which is formed with a recess 11 by stamping, and the part outside the periphery of the recess 11 and not stamped is the sealing edge 12. When packaging the soft package battery 100, the battery cell 20 is first placed in the recess 11, and then the two shell parts 101 are folded, the recesses 11 of the two shell parts 101 enclose the containing cavity 13, and the sealing edges 12 of the two shell parts 101 are sealed and bonded to close the containing cavity 13.

[0031] It can be understood that in other embodiments, with reference to Figure 11 , one of the two shell parts 101 is formed with a recess 11 by stamping, and the part outside the periphery of the recess 11 and not stamped is the sealing edge 12. The other shell part 101 is not stamped. When packaging the soft package battery 100, the battery cell 20 is first placed in the recess 11, and then the two shell parts 101 are folded, the recess 11 of one of the shell parts 101 and the other shell part 101 enclose the containing cavity 13, and the sealing edge 12 of one of the shell parts 101 and the other shell part 101 are sealed and bonded to close the containing cavity 13.

[0032] The two implementation manners are suitable for different thicknesses of the battery cell. Specifically, the implementation manner that both of the two shell parts 101 are formed with a recess 11 by stamping is suitable for a battery cell with a larger thickness, and the implementation manner that only one of the two shell parts 101 is formed with a recess 11 by stamping is suitable for a battery cell with a smaller thickness. Those skilled in the art can make reasonable selection and design according to actual needs to adapt to different actual situations.

[0033] In the current embodiment, one edge of each recess 11 is adjacent to the other recess 11, and the remaining three edges are surrounded by the corresponding sealing edge 12. It can be understood that in other embodiments, each recess 11 can be configured to have its four edges surrounded by the corresponding sealing edge 12.

[0034] The material of the shell 10 is composed of a first inner insulating layer, a second metal layer, and a third outer insulating layer in a three-layer structure. In the current embodiment, the shell 10 adopts an aluminum plastic film.

[0035] The material of the first inner insulating layer can be a film formed of one or more of polypropylene (PP), cast polypropylene (CPP), and the like.

[0036] The second metal layer can be one or more of aluminum, aluminum alloy, copper, nickel, and the like.

[0037] The third outer insulating layer can be made of one or more of the following materials: polycaprolactam, polyethylene terephthalate (PET), or polybutylene succinate (PBS).

[0038] <Example Battery Module> Studies have found that pouch cells generally have a thinner casing compared to prismatic and cylindrical batteries, typically between 80 and 200 micrometers. The casing is usually made of metal foil, covered with an insulating layer, and the sealing edges are often achieved using hot-pressing or bonding processes with adhesive layers. Compared to batteries that use welding to fix the cover, this sealed structure is more prone to cracking under mechanical and thermal stress. Furthermore, pouch cells are difficult to integrate with directional pressure relief mechanisms, and failure often begins at the sealing edge. Especially with the current trend towards high energy density and fast charging performance, the longitudinal dimensions of pouch cells continue to increase, and high-rate charge / discharge applications are becoming increasingly common, further increasing the risk of sealing failure.

[0039] In the event of thermal runaway, the high-pressure gas accumulated inside can rupture the sealing edges, causing the sealing structure to fail. High-temperature electrolyte, gas, and metal fragments will then be ejected, easily triggering a chain reaction in adjacent batteries and accelerating the propagation of thermal runaway. Furthermore, the pouch cell casing itself has relatively low mechanical strength and is prone to deformation, typically requiring encapsulation with potting compound or external metal end plates for overall fixation. This structure compresses the venting and heat dissipation gaps between batteries, making it easier for heat to accumulate within the battery module, further exacerbating the risk of thermal runaway propagation.

[0040] In view of this, refer to Figure 1 and Figure 2 This invention provides a battery module 200, which includes multiple pouch cells 100 and a fixed end plate 30. The multiple pouch cells 100 extend along a first direction and are stacked along a second direction. The fixed end plate 30 protects the multiple pouch cells 100, fixing them in place and preventing the battery pack formed by the multiple pouch cells 100 from being impacted and causing the casing 10 of the pouch cells 100 to break. It should be noted that, to ensure the protective effect, the thickness of the fixed end plate 30 is greater than the thickness of the casing 10.

[0041] It should be noted that in the accompanying drawings of this invention, arrows Z+ and Z- are used to indicate opposite sides in the height direction, with arrow Z+ pointing to the side where the top is located; arrows X+ and X- are used to indicate opposite sides in the first direction; and arrows Y+ and Y- are used to indicate opposite sides in the second direction. The height direction, the first direction, and the second direction are perpendicular to each other.

[0042] As one possible implementation, the fixed end plate 30 may include a metal plate, and the metal material may be one or more of aluminum, aluminum alloy, stainless steel, and titanium alloy.

[0043] It should be noted that the two surfaces of the fixed end plate 30 in the height direction may be provided with an insulating structure. For example, the insulating layer can be attached to the surface of the fixed end plate 30 by spraying or pasting to achieve electrical insulation between the fixed end plate 30 and the soft-pack battery 100.

[0044] refer to Figures 4 to 7 The sealing portion 12 includes a first sealing portion 121 extending beyond the recess 11 in the height direction, which seals the receiving cavity 13 in a first direction. In the current embodiment, the first sealing portion 121 is bent twice to form a first segment 1211, a second segment 1212, and a third segment 1213. This implementation enhances the protection of the first sealing portion 121, reduces the risk of high-temperature gas inside the soft-pack battery 100 breaking through the first sealing portion 121 and causing seal failure, thereby reducing safety hazards such as leakage and gas leakage. In addition, since the bending direction of the second segment 1212 is close to the recess 11, this implementation can also reduce the size of the first sealing portion 121 in the height direction, thereby reducing the size of the battery module 200 in the height direction, which helps to improve the space utilization and energy density of the battery module 200.

[0045] refer to Figure 2 The fixed end plate 30 and the first sealing edge 121 are located on the same side of the multiple pouch batteries 100 in the height direction, and the fixed end plate 30 is provided with an exhaust hole 31. Since the fixed end plate 30 and the first sealing edge 121 are located on the same side of the battery module 200, the exhaust hole 31 on the fixed end plate 30 can provide an exhaust path for the high-temperature gas released from the first sealing edge 121, thereby reducing the residence time of the high-temperature gas in the internal space of the module and preventing the high-temperature gas released by the pouch battery 100 during thermal runaway from accumulating inside the battery module 200, thereby reducing the risk of thermal shock to adjacent pouch batteries 100.

[0046] Further, refer to Figure 2 , Figure 5 and Figure 6The sealing width of the first sealing edge 121 is d1 in mm. In the first direction, the dimension of the fixed end plate 30 is L in mm, and the dimension of the vent hole 31 is L1 in mm. 0.3 ≤ d1 L1 / L≤8.4. For example, d1 L1 / L can be 0.3, 0.4, 0.65, 0.8, 1, 1.5, 2, 2.8, 3.6, 4.5, 5.5, 6, 6.5, 7, 8, or 8.4.

[0047] When d1 When L1 / L is too small, the exhaust port 31 provides an excessively narrow channel for the high-temperature gas, resulting in low exhaust efficiency. Consequently, the high-temperature gas generated by the thermal runaway of the pouch battery 100 is difficult to expel quickly and tends to accumulate inside the module, thereby accelerating heat propagation and significantly increasing the risk of cascading thermal runaway between adjacent pouch batteries 100.

[0048] When d1 When L1 / L is too large, it will excessively weaken the structural strength of the fixed end plate 30, which is prone to deformation or even structural failure under mechanical load, which is not conducive to the structural stability and safety performance of the battery module 200.

[0049] According to the battery module 200 provided in the embodiment of the present invention, d1 Limiting L1 / L within the aforementioned range ensures that the vent 31 provides sufficient outlet for the high-temperature gas released from the first sealing edge 121, reducing the residence time of the high-temperature gas in the internal space of the module and preventing the high-temperature gas released from the pouch battery 100 during thermal runaway from accumulating inside the battery module 200, thereby reducing the risk of thermal shock to adjacent pouch batteries 100. At the same time, it does not excessively weaken the structural strength of the fixed end plate 30, reducing the possibility of deformation or even structural failure under mechanical load, thus helping to improve the structural stability and safety performance of the battery module 200.

[0050] It should be noted that the reference Figure 5 and Figure 6 The sealing width d1 of the first sealing portion 121 refers to the length of the sealing portion 12 in the unfolded state in the direction perpendicular to the length of the soft-pack battery 100 (i.e., the first direction).

[0051] It should be noted that the present invention does not impose a particular limitation on the number of exhaust holes 31. As an example, see reference... Figure 3The number of exhaust holes 31 can be multiple, and the size L1 of the exhaust holes 31 refers to the sum of the sizes of the multiple exhaust holes 31 in the first direction, that is, L1 = L11 + L12 + L13 + L14. In some other embodiments, the number of exhaust holes 31 can also be one, in which case the size L1 of the exhaust hole 31 refers to the size of the exhaust hole 31 in the first direction.

[0052] It should be noted that the shape of the exhaust hole 31 can be implemented in various ways. For example, the exhaust hole 31 can be a circular hole, a square hole, or a long strip hole. The present invention does not impose any particular limitation.

[0053] refer to Figure 8 The projection of the vent 31 along the height direction coincides with the projection of at least two adjacent first sealing portions 121 along the height direction in the second direction. In this way, the vent 31 can spatially cover the first sealing portion 121 areas of two adjacent pouch cells 100. When one pouch cell 100 experiences thermal runaway, the high-temperature gas released from its first sealing portion 121 can be discharged from the battery module 200 through the vent 31; similarly, when an adjacent pouch cell 100 also experiences thermal runaway or gas is discharged from its first sealing portion 121 after being heated, the gas can also be discharged through the vent 31. According to the battery module 200 provided by the present invention, a single vent 31 can accommodate the first sealing portions 121 of multiple pouch cells 100, thus ensuring the venting efficiency of the vent 31 while reducing the number of openings, which helps optimize the structural integrity and overall strength of the fixed end plate 30.

[0054] refer to Figure 9 In the height direction, the distance from the vent 31 to the first sealing edge 121 is H1, in mm, and 0.5 ≤ H1 ≤ 8. For example, H1 can be 0.5, 0.8, 1.2, 1.6, 2, 2.5, 3, 3.4, 3.9, 4.5, 5.2, 5.8, 6.4, 7.2 or 8.

[0055] When the distance from the vent 31 along the height direction to the first sealing edge 121 is too small, after the pouch battery 100 experiences thermal runaway, the high-temperature gas released from the first sealing edge 121 will rapidly accumulate in the confined space and cannot be discharged in time. The trapped high-temperature gas will further aggravate the thermal load of adjacent pouch batteries 100, causing the overall temperature to rise and increasing the risk of thermal runaway propagation.

[0056] When the distance from the vent 31 to the first sealing edge 121 along the height direction is too large, it will increase the size of the battery module 200 in the height direction, which is not conducive to space utilization and energy density of the battery module 200.

[0057] According to the battery module 200 provided in the embodiment of the present invention, the distance from the vent 31 to the first sealing edge 121 along the height direction is limited to the above-mentioned numerical range. This ensures that there is sufficient venting space between the fixed end plate 30 and the first sealing edge 121, thereby reducing the risk of thermal runaway propagation of the battery module 200, and also ensures the space utilization and energy density of the battery module 200.

[0058] refer to Figure 2 and Figure 9 The battery module 200 also includes a separator 40, which is located between the fixed end plate 30 and the first sealing edge 121. The projection of the separator 40 along the height direction covers the projection of the vent 31 along the height direction. The melting point of the separator 40 is T, in °C, and T ≥ 900. For example, T can be 900, 910, 920, 930, 945, 960, 970, 980, 990, 1000, 1100, 1150, or 1200.

[0059] According to the battery module 200 provided by the present invention, the separator 40 is located between the fixed end plate 30 and the first sealing portion 121. Therefore, when the soft-pack battery 100 experiences thermal runaway, the high-temperature gas released at the first sealing portion 121 can destroy the separator 40 at the nearest exhaust port 31, allowing the high-temperature gas to be discharged from the battery module 200 through the exhaust port 31. The separators 40 at the other exhaust ports 31 are not destroyed, thus preventing the high-temperature gas discharged from the battery module 200 from returning to the battery module 200 through the other exhaust ports 31, thereby avoiding the transfer of heat to the adjacent soft-pack battery 100 and preventing the spread of thermal runaway.

[0060] It is understood that the material of the insulating member 40 can be implemented in various ways, and the present invention does not impose any particular limitation on it. As an example, the material of the insulating member 40 can be mica, calcium silicate, ceramic fiber, aluminum silicate fiber, basalt fiber, etc.

[0061] refer to Figure 9 The dimension of the separator 40 in the height direction is H2, in mm, and 0.2 ≤ H2 ≤ 3. For example, H2 can be 0.2, 0.3, 0.45, 0.6, 0.8, 1, 1.2, 1.45, 1.7, 2, 2.2, 2.4, 2.6, 2.8 or 3.

[0062] When the size of the separator 40 in the height direction is too small, the separator 40 is less effective at preventing high-temperature gas from returning to the inside of the battery module 200. This will increase the thermal load on the other pouch cells 100 in the battery module 200 and increase the risk of thermal runaway propagation.

[0063] When the size of the separator 40 in the height direction is too large, it will increase the size of the battery module 200 in the height direction, which is not conducive to space utilization and energy density of the battery module 200.

[0064] According to the battery module 200 provided in the embodiments of the present invention, the size of the separator 40 in the height direction is limited to the above-mentioned numerical range. This ensures that the separator 40 can block the high-temperature gas from returning to the interior of the battery module 200, thereby suppressing the spread of thermal runaway in the battery module 200, and also ensures the space utilization and energy density of the battery module 200.

[0065] As one possible implementation, the separator 40 can be fixed to the side of the fixed end plate 30 facing the pouch battery 100 by adhesive bonding. This implementation has a simple structure, does not require additional fixing components for the separator 40, and can simplify the installation process and improve assembly efficiency.

[0066] refer to Figure 10 The battery module 200 includes an adhesive component 50, which adhesively bonds the separator 40 and the fixed end plate 30. By adhesively fixing the separator 40 to the fixed end plate 30, the risk of displacement or detachment under vibration or impact conditions can be reduced, thereby ensuring the installation stability of the separator 40.

[0067] refer to Figure 3 The adhesive component 50 includes a first adhesive region 51 and a second adhesive region 52 spaced apart in a first direction, the boundaries of which are shown by dashed lines. At least one vent 31 is provided between the first adhesive region 51 and the second adhesive region 52. By constructing multiple adhesive regions, the stability of the bond can be enhanced. Furthermore, since at least one vent 31 is provided between the first adhesive region 51 and the second adhesive region 52, the adhesive component 50 does not completely cover or block the venting passage. This implementation does not increase the resistance to the discharge of high-temperature gas through the vent 31, thereby ensuring the smooth discharge of high-temperature gas.

[0068] refer to Figure 3 , Figure 9 and Figure 10 The projection of the adhesive component 50 along the height direction at least partially coincides with the projection of the vent 31 along the height direction. The dimension of the adhesive component 50 in the height direction is H3, in mm, and H3 ≤ 2. For example, H3 can be 0.1, 0.15, 0.22, 0.3, 0.4, 0.55, 0.7, 0.9, 1.1, 1.3, 1.5, 1.65, 1.8, 1.9 or 2.

[0069] When the dimension of the adhesive component 50 in the height direction is too large, the high-temperature gas released during thermal runaway of the pouch battery 100 will be blocked by the adhesive component 50 and accumulate inside the battery module 200 when it is discharged through the vent 31. The trapped high-temperature gas will further aggravate the thermal load of adjacent pouch batteries 100, causing the overall temperature to rise and increasing the risk of thermal runaway propagation.

[0070] According to the battery module 200 provided by the present invention, setting the dimensions of the adhesive 50 in the height direction within the above-mentioned numerical range can reduce the resistance of high-temperature gas discharged through the exhaust port 31, thereby ensuring the discharge efficiency of high-temperature gas and preventing the high-temperature gas released by the soft-pack battery 100 during thermal runaway from accumulating inside the battery module 200.

[0071] refer to Figure 2 The battery module 200 also includes two side plates 32, which are respectively disposed on opposite sides of the plurality of pouch batteries 100 in the second direction and are fixedly connected to the fixed end plate 30. The fixed connection between the two side plates 32 and the fixed end plate 30 can enhance the strength of the overall structure, thereby reducing the risk of structural failure of the fixed end plate 30 due to the opening of the vent 31.

[0072] It is understood that there are various ways to fix the two side plates 32 to the fixed end plate 30, and the present invention does not impose any particular limitation on this. For example, the two side plates 32 and the fixed end plate 30 can be fixedly connected by means of integral connection, riveting, welding, bonding, snap-fitting, screwing, etc.

[0073] refer to Figure 3 The vent 31 has a larger dimension in the second direction than in the first direction. Since multiple pouch cells 100 are stacked along the second direction, making the vent 31 larger in the second direction than in the first direction allows the projection of the vent 31 in the height direction to cover the projection of the multiple pouch cells 100 in the height direction as much as possible. This reduces the number of openings while ensuring the venting efficiency of the vent 31.

[0074] refer to Figure 9 The fixed end plate 30 includes a flat portion 301 and a recessed portion 302. The recessed portion 302 protrudes from the flat portion 301 toward the side where the battery cell 20 is located, and the vent 31 is provided in the recessed portion 302. After multiple battery modules 200 are stacked along the height direction, since the fixed end plate 30 is recessed along the height direction toward the side where multiple pouch batteries 100 are located, high-temperature gas can be discharged from the vent 31 and then discharged from the stacked multiple battery modules 200 through the recessed portion 302.

[0075] refer to Figure 3The recess 302 extends in the second direction to both ends of the fixed end plate 30. In this way, after the high-temperature gas is discharged from the exhaust port 31, it can be discharged in two opposite directions in the second direction to ensure exhaust efficiency.

[0076] refer to Figure 3 There are multiple exhaust holes 31. In the first direction, the shortest distance between two adjacent exhaust holes 31 is D1, in mm, where 30≤D1≤150. For example, D1 can be 30, 40, 50, 60, 70, 80, 90, 100, 110, 120, 130, 140 or 150.

[0077] When the shortest distance between two adjacent exhaust holes 31 along the first direction is too small, it will excessively weaken the structural strength of the fixed end plate 30. Under mechanical load, it is prone to deformation or even structural failure, which is not conducive to the structural stability and safety performance of the battery module 200.

[0078] When the shortest distance between two adjacent vent holes 31 along the first direction is too large, it will limit the size of the vent holes 31 on the fixed end plate 30. As a result, the high-temperature gas released during thermal runaway of the pouch battery 100 cannot be discharged in time and is prone to accumulate inside the battery module 200. The trapped high-temperature gas will further aggravate the thermal load of adjacent pouch batteries 100, causing the overall temperature to rise and increasing the risk of thermal runaway propagation.

[0079] According to the battery module 200 provided in the embodiment of the present invention, the shortest distance between two adjacent vent holes 31 along the first direction is limited to the above-mentioned numerical range. This can ensure the size of the vent holes 31 in the first direction, thereby ensuring the discharge efficiency of high-temperature gas and preventing the high-temperature gas released by the soft-pack battery 100 during thermal runaway from accumulating inside the battery module 200. It can also reduce the risk of structural failure of the fixed end plate 30 due to the opening of the vent holes 31.

[0080] refer to Figure 3 and Figure 5 In the first direction, the dimension of the housing 10 is L2 in mm, and the distance between two adjacent exhaust holes 31 is D1 in mm, where L2 ≥ 400 and 30 ≤ D1 ≤ 140. For example, D1 can be 30, 40, 50, 60, 70, 80, 90, 100, 110, 120, 130, 135 or 140.

[0081] When the size of the casing 10 in the first direction is greater than 400mm, the heat generated inside the pouch battery 100 is concentrated and the exhaust is not smooth. The first sealing edge 121 is at greater risk of being broken by the high-temperature gas released when the pouch battery 100 experiences thermal runaway. Therefore, the distance between two adjacent exhaust holes 31 needs to be small to ensure that the exhaust hole 31 has a large size in the first direction, so that the projection of the exhaust hole 31 in the height direction can cover the projection of the first sealing edge 121 in the height direction as much as possible. This ensures that when the pouch battery 100 experiences thermal runaway, the high-temperature gas accumulated inside can be discharged quickly and evenly through the nearest exhaust hole 31.

[0082] <Example Electrical Equipment> refer to Figure 12 This invention provides an electrical device 300, which includes a battery module 200.

[0083] By way of example only, electrical equipment 300 can be, but is not limited to, vehicles, ships, aircraft, household appliances, and industrial equipment. For example, vehicles can be passenger cars, trucks, engineering vehicles, etc.

[0084] In addition, electrical equipment 300 can also be used for the storage, conversion and release of recyclable electrical energy.

[0085] In a non-restrictive example, refer to Figure 12 The electrical equipment 300 can be an electric vehicle, and the battery module 200 can be used as a power source to provide power to the electric vehicle.

[0086] <Examples and Comparative Examples> The following specific embodiments and comparative examples are provided to illustrate how the battery provided by the present invention helps reduce the risk of deformation of the fixed end plate and the risk of thermal runaway of adjacent batteries.

[0087] I. The batteries in the following examples and comparative examples can be prepared using the following methods.

[0088] 1. The prepared positive electrode active material, conductive agent acetylene black, and binder PVDF are mixed, and solvent NMP is added. The mixture is stirred under vacuum until the system is homogeneous to obtain a positive electrode slurry. The positive electrode slurry is uniformly coated on both surfaces of the positive electrode current collector aluminum foil, air-dried at room temperature, and then transferred to an oven for further drying. After cold pressing and slitting, the positive electrode sheet is obtained. Specifically, the mass ratio of positive electrode material: conductive agent: binder satisfies (92~98): (4~1): (4~1).

[0089] 2. Preparation of the negative electrode: The negative electrode active material graphite, conductive agent acetylene black, thickener CMC, and binder SBR are mixed, and deionized water is added as a solvent. The mixture is stirred under vacuum until the system is homogeneous to obtain a negative electrode slurry. The negative electrode slurry is uniformly coated on both surfaces of the negative electrode current collector copper foil, air-dried at room temperature, and then transferred to an oven for further drying. After cold pressing and slitting, the negative electrode sheet is obtained. The ratio of negative electrode graphite: conductive agent: thickener: binder is (90~96): (4~2): (2~1): (4~1).

[0090] 3. Preparation of electrolyte: Ethylene carbonate (EC), ethyl methyl carbonate (EMC), and diethyl carbonate (DEC) were mixed in a volume ratio of 1:1:1 to obtain an organic solvent. Then, fully dried lithium salt LiPF6 was dissolved in the mixed organic solvent to prepare an electrolyte with a concentration of 1 mol / L.

[0091] 4. Preparation of the diaphragm: Polyethylene film is selected as the diaphragm.

[0092] 5. Preparation of lithium-ion batteries: The aforementioned positive electrode sheet, separator, and negative electrode sheet are stacked in sequence, and then wound or stacked to obtain a bare battery cell. The bare battery cell is placed in an outer packaging shell, dried, injected with electrolyte, and then packaged, allowed to stand, formed, and capacitively adjusted to obtain a lithium-ion battery. The positive electrode active material can be selected from one or more lithium-containing positive electrode active materials, including lithium iron phosphate, ternary materials containing nickel, cobalt, and manganese, and lithium manganese iron phosphate. The negative electrode active material can be selected from one or more negative electrode active materials, including artificial graphite, natural graphite, silicon carbide, silicon oxide, and lithium titanate.

[0093] In this test, the positive electrode active material of the battery was selected as a nickel-cobalt-manganese ternary LiNi0.6Co0.2Mn0.2O2, with a mass ratio of positive electrode active material: conductive agent: binder satisfying 96:2:2. The negative electrode active material was selected as artificial graphite, with a ratio of negative electrode active material: conductive agent: thickener: binder satisfying 95:2:1:2.

[0094] 6. Fabrication of Soft-Pack Battery Modules Multiple pouch batteries are connected in series or parallel and then installed into a fixed end plate to form a battery module.

[0095] II. The performance involved in the following embodiments and comparative examples can be tested using the following methods.

[0096] 1. Test Method 1: Fixed End Plate Deformation Following the battery fabrication method described above, for each embodiment and comparative example, corresponding batteries were prepared. Twelve prepared batteries were then assembled into a battery module, with all other test conditions remaining consistent. A reference surface was created using the four corners of the top surface of the fixed end plate as reference points. The distance between the fixed end plate and the reference surface was measured and denoted as A1.

[0097] The battery module was mounted on a vibration table according to GB / T2423.43. The testing process was conducted according to GB / T2423.56. Random and fixed-frequency vibration loads were applied in each direction, and the loading sequence should preferably be random z-axis, fixed-frequency z-axis, random y-axis, fixed-frequency y-axis, random x-axis, fixed-frequency x-axis (the direction connecting the front and rear of the battery is the x-axis direction, and the other horizontal direction perpendicular to the x-axis is the y-axis direction). The vibration frequency, power spectral density (PSD), vibration time, etc., are shown in the table below.

[0098] After the vibration is complete, remove the fixed end plate from the battery module and measure the distance between the center point of the fixed end plate and the reference surface again, which is recorded as A2. When |A1-A2|>5mm, it is recorded as unqualified; when 3mm≤|A1-A2|<5mm, it is recorded as qualified; when |A1-A2|≤3mm, it is recorded as good.

[0099] 2. Test Method 2: Thermal Runaway Time Test of Adjacent Batteries The battery module was prepared according to the above preparation method. For each embodiment and comparative example, the prepared 9 batteries were connected in series to form a battery module. All other structures were the same.

[0100] Charge each battery in the battery pack to its upper limit voltage using a 0.33C rate. Then, using a high-temperature resistant steel needle with a diameter of 3 mm, penetrate the central pouch cell (i.e., the 5th cell in the battery pack, starting from the edge) from the height direction at a speed of 25 ± 5 mm per second. Induce thermal runaway in the central pouch cell. Start timing from the moment the central pouch cell experiences thermal runaway and calculate the shortest time for thermal runaway in the other batteries in the battery pack. If the time is greater than or equal to 6 minutes, it is considered good; if the time is between 5 and 6 minutes, it is considered acceptable; and if the time is less than 5 minutes, it is considered unacceptable.

[0101] For different batteries, the upper and lower voltage limits need to be adjusted accordingly during testing: Lithium iron phosphate (LFP) - upper limit 3.65V, lower limit 2.5V; Nickel-cobalt-manganese ternary (NCM) - upper limit 4.25V, lower limit 2.5V; Lithium manganese iron phosphate (LFMP) - upper limit 4.25V, lower limit 2.5V; Lithium nickel manganese oxide (LiMC) - upper limit 4.8V, lower limit 3.5V. The battery used in this test is a nickel-cobalt-manganese ternary battery, with an upper limit voltage of 4.25V during charging.

[0102] The table below lists test data for several embodiments and comparative examples.

[0103] Referring to the table above, in any one of Examples 1 to 12, formula d1 The value of L1 / L falls within the range of 0.3 to 8.4. Analysis of the table above shows that in any of Examples 1 to 12, the battery demonstrated satisfactory or good performance in both Test 1 and Test 2. This verifies the validity of formula d1. When the value of L1 / L falls within the range of 0.3 to 8.4, it not only has a lower risk of deformation of the fixed end plate, but also a lower risk of thermal runaway of adjacent cells.

[0104] In contrast, in Comparative Example 1, formula d1 The value of L1 / L is less than 0.3. Analysis of the table above shows that the battery provided in Example 1 performed well in Test 1, but failed in Test 2. This verifies the validity of formula d1. When the value of L1 / L is less than 0.3, the risk of deformation of the fixed end plate is relatively high.

[0105] Meanwhile, in Comparative Example 2, formula d1 The value of L1 / L is greater than 8.4. Analysis of the table above shows that the battery provided in Comparative Example 2 performs well in Test 2, but fails in Test 1. This verifies the validity of formula d1. When the value of L1 / L is greater than 8.4, the risk of thermal runaway of adjacent batteries is relatively high.

[0106] It should be understood that the term "comprising" and its variations as used in this invention are open-ended, meaning "including but not limited to". The term "according to" means "at least in part according to". The term "one embodiment" means "at least one embodiment"; the term "another embodiment" means "at least another embodiment".

[0107] It should be understood that although terms such as "first" or "second" may be used in this invention to describe various elements (such as the first adhesive region and the second adhesive region), these elements are not defined by these terms, which are only used to distinguish one element from another.

[0108] The scope of protection of this invention is not limited to the above embodiments. Any variations or substitutions that can be conceived by those skilled in the art within the technical scope disclosed in this invention should be included within the scope of protection of this invention. Therefore, the scope of protection of this invention should be determined by the scope of the claims.

Claims

1. A battery module (200), characterized in that, The application relates to a soft package battery (100) comprising a plurality of soft package batteries (100) extending along a first direction and stacked along a second direction, the first direction being perpendicular to the second direction, the soft package battery (100) comprising a shell (10) and an electric core (20), the shell (10) comprising two shell parts (101), at least one shell part (101) being provided with a recess (11) and an edge sealing part (12) located at least part of the outer periphery of the recess (11), the recess (11) and the other shell part (101) enclosing a containing cavity (13), the edge sealing part (12) and the shell part (101) opposite to the edge sealing part (12) being sealingly bonded to close the containing cavity (13), the containing cavity (13) containing the electric core (20), the edge sealing part (12) comprising a first edge sealing part (121) sealing the containing cavity (13) in the first direction; and The projection of the exhaust hole (31) in the height direction partially coincides with the projection of at least two first edge sealing parts (121) adjacent in the second direction in the height direction. A fixed end plate (30) is located on the same side of the plurality of soft package batteries (100) in the height direction as the first edge sealing portion (121), the first direction, the second direction, and the height direction are perpendicular to each other, wherein the fixed end plate (30) is provided with an exhaust hole (31), the sealing width of the first edge sealing portion (121) is d1, unit: mm, in the first direction, the size of the fixed end plate (30) is L, unit: mm, the size of the exhaust hole (31) is L1, unit: mm, 0.3≤d1 L1 / L≤8.

4.

2. The battery module (200) according to claim 1, characterized in that In the height direction, the distance from the exhaust hole (31) to the first edge sealing part (121) is H1, mm, 0.5<=H1<=8.

3. The battery module (200) according to claim 1, characterized in that, Further comprising a separation piece (40) located between the fixed end plate (30) and the first edge sealing part (121), the projection of the separation piece (40) in the height direction covering the projection of the exhaust hole (31) in the height direction, the melting point of the separation piece (40) being T, ℃, T>=900.

4. The battery module (200) according to claim 1, characterized in that, The size of the separation piece (40) in the height direction is H2, mm, 0.2<=H2<=3.

5. The battery module (200) according to claim 4, characterized in that Further comprising a bonding piece (50) bonding the separation piece (40) and the fixed end plate (30).

6. The battery module (200) according to claim 4, characterized in that The bonding piece (50) comprises a first bonding area (51) and a second bonding area (52) spaced apart in the first direction, at least one exhaust hole (31) being arranged between the first bonding area (51) and the second bonding area (52).

7. The battery module (200) according to claim 6, characterized in that The projection of the bonding piece (50) in the height direction at least partially coincides with the projection of the exhaust hole (31) in the height direction, the size of the bonding piece (50) in the height direction being H3, mm, H3<=2.

8. The battery module (200) according to claim 6, characterized in that, The size of the exhaust hole (31) in the second direction is greater than the size of the exhaust hole (31) in the first direction.

9. The battery module (200) according to any one of claims 1 to 8, characterized in that The fixed end plate (30) comprises a flat part (301) and a recess part (302) protruding from the flat part (301) to the side where the electric core (20) is located, the exhaust hole (31) being arranged in the recess part (302).

10. The battery module (200) according to any one of claims 1 to 8, characterized in that, The recess part (302) extends to both ends of the fixed end plate (30) in the second direction.

11. The battery module (200) according to claim 10, characterized in that The number of exhaust holes (31) is multiple, and the shortest distance between two adjacent exhaust holes (31) in the first direction is D1, mm, 30<=D1<=150.

12. The battery module (200) according to any one of claims 1 to 8, characterized in that ​ 13. The battery module (200) according to any one of claims 1 to 8, characterized in that In the first direction, the size of the shell (10) is L2, unit: mm, the shortest distance between two adjacent exhaust holes (31) is D1, unit: mm, L2≥400, 30≤D1≤140.

14. The battery module (200) of claim 1, wherein, Two side plates (32) are further included, which are respectively arranged on opposite sides of the plurality of soft package batteries (100) in the second direction and fixedly connected with the fixed end plate (30).

15. An electrical device (300) characterized by The battery module (200) of any one of claims 1 to 14 is included.

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