Battery pack

Abstract

The present invention relates to the technical field of batteries, and provides a battery pack, which comprises: a box body having a first plate part and a second plate part which are oppositely arranged; the battery cell is arranged in the box body and comprises a shell and a pole, and the shell is provided with a first end face and a second end face which are opposite to each other; the first end face is convexly provided with the pole and the convex hull, the pole and the convex hull are arranged on the first end face at an interval, the convex hull is connected with the first plate part in a supporting manner, and the second end face is connected with the second plate part in a supporting manner; the busbar is connected to the pole and located between the pole and the first plate part, and the distance between the convex hull and the first plate part is smaller than the distance between the busbar and the first plate part. The shell of the battery cell of the battery pack is used as a supporting force bearing piece, so that the first plate part can be prevented from being greatly deformed under the impact effect, the thickness of the first plate part can be reduced, the weight of the battery pack is reduced, and the lightweight design of the battery pack is facilitated.

Description

Technical Field

[0001] This invention relates to the field of battery technology, and more particularly to a battery pack. Background Technology

[0002] A battery pack consists of a housing and battery modules assembled inside the housing. Each battery module is composed of multiple cells connected in a specific series-parallel configuration. The housing provides physical support for the battery modules, protecting them from external impacts, pressure, and other damage, while also preventing the intrusion of moisture, dust, and other impurities. However, current battery packs rely solely on the rigidity of the housing itself to withstand external impacts, resulting in a relatively thick housing, which is detrimental to lightweight battery pack design. Summary of the Invention

[0003] This invention provides a battery pack to solve the problem in the prior art where the battery pack relies solely on the rigidity of the casing to withstand external impacts, resulting in a thicker casing that is not conducive to lightweight battery pack design.

[0004] This invention provides a battery pack, comprising: The housing has a first plate portion and a second plate portion that are arranged opposite to each other; A battery cell, disposed within the housing, includes a housing and a terminal post. The housing has a first end face and a second end face facing away from each other. The first end face is provided with the terminal post and a protrusion. The terminal post and the protrusion are spaced apart on the first end face. The protrusion is supported and connected to the first plate portion. The second end face is supported and connected to the second plate portion. A busbar is connected to the pole and located between the pole and the first plate portion, wherein the distance between the convex bulge and the first plate portion is less than the distance between the busbar and the first plate portion.

[0005] According to a battery pack provided by the present invention, the distance between the first end face and the first plate portion in the direction perpendicular to the first end face is H1, the thickness of the busbar in the direction perpendicular to the first end face is H2, and the height of the terminal post relative to the first end face is H3, where 0.1mm≤H1-(H2+H3)≤5mm.

[0006] According to a battery pack provided by the present invention, the side of the convex bulge away from the first end face is a connecting surface, the connecting surface is supported and connected to the first plate portion, the number of convex bulges is at least one, the total area of ​​the connecting surfaces of all the convex bulges is S1, the area of ​​the first end face is S0, and 0.1≤S1 / S0≤0.9.

[0007] According to a battery pack provided by the present invention, the side of the convex bulge away from the first end face is a connecting surface, the connecting surface is supported and connected to the first plate portion, and the area of ​​the connecting surface is S1', where S1' ≥ 10 mm.2 .

[0008] According to a battery pack provided by the present invention, the battery cell further includes an explosion-proof valve, the explosion-proof valve is disposed on the first end face, the terminal post, the explosion-proof valve and the convex bulge are arranged along the length direction of the first end face, and the convex bulge is provided between the terminal post and the explosion-proof valve.

[0009] According to a battery pack provided by the present invention, the distance between the explosion-proof valve and the convex bulge is b, where b ≥ 10 mm.

[0010] According to a battery pack provided by the present invention, the first end face is provided with a plurality of said protrusions arranged along its length direction, and / or the first end face is provided with a plurality of said protrusions arranged along its width direction.

[0011] According to a battery pack provided by the present invention, the convex bulge has multiple layers of protrusions stacked in its convex direction.

[0012] According to a battery pack provided by the present invention, the first plate portion includes a first housing and a first cold plate, the first cold plate being located between the first housing and the convex bulge, the convex bulge being in contact with the first cold plate; The second plate portion includes a second housing and a second cold plate, the second cold plate being located between the second housing and the second end face, and the second end face being in contact with the second cold plate.

[0013] According to a battery pack provided by the present invention, at least one of the convex bulge and the busbar is fixed to the first plate portion by adhesive bonding.

[0014] The battery pack provided by this invention features a protrusion on the first end face of the cell's outer casing. This protrusion is supported and connected to the first plate of the housing, and the second end face is supported and connected to the second plate of the housing. This allows the cell's outer casing to act as a load-bearing component, supporting the first and second plates. This prevents significant deformation of the first plate under impact, thereby reducing its thickness and the weight of the battery pack, facilitating lightweight design. Furthermore, while ensuring the first plate does not compress the busbars and terminals, the distance between the busbars and the first plate can be reduced, increasing the cell's volume and fully utilizing the space within the housing, thus improving the battery pack's energy density. Simultaneously, by setting the distance between the protrusion and the first plate to be less than the distance between the busbars and the first plate, the protrusion acts as the primary load-bearing component of the cell, protecting the busbars and terminals and improving the battery pack's safety performance. Attached Figure Description

[0015] To more clearly illustrate the technical solutions in this invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of this invention. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0016] Figure 1 This is one of the structural schematic diagrams of the battery pack provided by the present invention.

[0017] Figure 2 This is a schematic diagram of the structure of the battery cell in the battery pack provided by the present invention.

[0018] Figure 3 This is the second schematic diagram of the battery pack provided by the present invention.

[0019] Figure 4 This is the third schematic diagram of the battery pack provided by the present invention.

[0020] Figure 5 This is one of the schematic diagrams showing the arrangement of the battery cells in the battery pack provided by the present invention.

[0021] Figure 6 This is the second schematic diagram of the cell arrangement in the battery pack provided by the present invention.

[0022] Figure 7 This is the fourth schematic diagram of the battery pack provided by the present invention.

[0023] Figure 8 yes Figure 7 Sectional view at AA.

[0024] Figure label: 11. First plate section; 12. Second plate section; 2. Battery cell; 20. Outer shell; 21. Housing; 22. Cover plate; 221. First end face; 222. Second end face; 223. Protrusion; 2231. Connecting surface; 23. Terminal post; 24. Explosion-proof valve; 3. Busbar; 31. Bending section; 4. Adhesive. Detailed Implementation

[0025] To make the objectives, technical solutions, and advantages of this invention clearer, the technical solutions of this invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of this invention. All other embodiments obtained by those skilled in the art based on the embodiments of this invention without creative effort are within the scope of protection of this invention.

[0026] In the description of the embodiments of the present invention, it should be noted that, unless otherwise explicitly specified and limited, the terms "first" and "second" are numbered for the purpose of clearly identifying product components and do not represent any substantial difference. The terms "installed," "connected," and "linked" should be interpreted broadly; for example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in the embodiments of the present invention according to the specific circumstances. Furthermore, "multiple" means two or more. In the specification and claims, "and / or" indicates at least one of the connected objects, and the character " / " generally indicates that the preceding and following related objects are in an "or" relationship.

[0027] The following is combined with Figures 1-8 The battery pack of the present invention is described.

[0028] like Figure 1 As shown, the battery pack provided in this embodiment of the invention includes a housing, battery cells 2, and a busbar 3. The housing has a first plate portion 11 and a second plate portion 12 disposed opposite to each other. The battery cell 2 is disposed inside the housing and includes a housing 20 and a terminal post 23. The housing 20 has a first end face 221 and a second end face 222 facing away from each other. The first end face 221 has a protruding terminal post 23 and a protruding bulge 223, which are spaced apart on the first end face 221. The protruding bulge 223 is supported and connected to the first plate portion 11, and the second end face 222 is supported and connected to the second plate portion 12. The busbar 3 is connected to the terminal post 23 and is located between the terminal post 23 and the first plate portion 11, and the distance between the protruding bulge 223 and the first plate portion 11 is less than the distance between the busbar 3 and the first plate portion 11.

[0029] Among them, see Figure 2 The outer casing 20 of the battery cell 2 includes a housing 21 and a cover plate 22. The electrode group of the battery cell 2 is located in the cavity formed by the housing 21 and the cover plate 22. The outer casing 20 of the battery cell 2 provides protection for the internal components of the battery cell 2 and can withstand certain external impacts.

[0030] In some alternative embodiments, such as Figure 2 As shown, the cover plate 22 has through holes for installing the pole post 23 and the explosion-proof valve 24. The pole post 23 passes through the through holes in the cover plate 22 and is inserted into the cover plate 22. A part of the pole post 23 is located in the receiving cavity and connected to the pole lug of the pole group, while a part protrudes from the outside of the cover plate 22 to form a pole post terminal.

[0031] In other embodiments, a first end face 221 is formed on the housing 21, and a second end face 222 is formed on the cover plate 22. The housing 21 has through holes for mounting the pole post 23 and the explosion-proof valve 24. The pole post 23 passes through the through holes in the housing 21 and is inserted into the housing 21. A portion of the pole post 23 is located in the receiving cavity and connected to the electrode tab of the pole assembly, while a portion protrudes from the outside of the housing 21 to form a pole post terminal.

[0032] The length and width directions of the first end face 221 are as follows: Figure 2 As shown. In this embodiment, the first end face 221 can be the outer surface of the cover plate 22, and the protrusion 223 can be integrally stamped from the cover plate 22, or it can be welded and fixed to the cover plate 22 as an independent structural component. Multiple battery cells 2 are arranged between the first plate portion 11 and the second plate portion 12, and the terminal posts of the multiple battery cells 2 are connected in series and parallel through the busbar 3 to form a battery module. The first end face 221 of the outer casing 20 faces the first plate portion 11, and the second end face 222 faces the second plate portion 12. The protrusion 223 on the first end face 221 is supported and connected to the first plate portion 11, and the second end face 222 is supported and connected to the second plate portion 12. That is, the outer casing 20 of the battery cell 2 is supported and disposed between the first plate portion 11 and the second plate portion 12.

[0033] The distance between the convex 223 and the first plate 11 is smaller than the distance between the busbar 3 and the first plate 11, so that the convex 223 can serve as the main load-bearing part of the cell 2, thereby transmitting the force to the outer shell 20 of the cell 2, avoiding or significantly reducing the force on the busbar 3, protecting the busbar 3 and the terminal post 23, and improving the safety performance of the battery pack.

[0034] The convex hull 223 can be directly connected to the first plate portion 11, or it can be connected through an intermediate medium, with the purpose of transmitting load between the first plate portion 11 and the convex hull 223. The second end face 222 can be directly connected to the second plate portion 12, or it can be connected through an intermediate medium, with the purpose of transmitting load between the second plate portion 12 and the second end face 222.

[0035] When the protrusion 223 is in direct contact with the first plate 11, the heat of the battery cell 2 can be transferred to the first plate 11 through the protrusion 223, thereby cooling the battery cell 2. Similarly, when the second end face 222 is in direct contact with the second plate 12, the heat of the battery cell 2 can be transferred to the second plate 12 through the second end face 222, thereby cooling the battery cell 2.

[0036] When the protrusion 223 is connected to the first plate portion 11 through an intermediate medium, the intermediate medium can be a thermally conductive medium to facilitate the transfer of heat from the battery cell 2 to the first plate portion 11 via the protrusion 223. Similarly, when the second end face 222 is connected to the first plate portion 11 through an intermediate medium, the intermediate medium can be a thermally conductive medium to facilitate the transfer of heat from the battery cell 2 to the second plate portion 12 via the second end face 222. The thermally conductive medium can be an adhesive with certain thermal conductivity properties.

[0037] In traditional battery pack structures, the battery pack relies solely on the rigidity of the first plate 11 to resist external impacts. Because the first plate 11 has a large area, insufficient rigidity can easily lead to deformation. To prevent excessive compression of the busbar 3 due to deformation of the first plate 11, a large space needs to be reserved between the busbar 3 and the first plate 11 in the structural design, and supporting foam needs to be placed between the battery module and the first plate 11. Some designs also incorporate concave and convex structures on the first plate 11 to enhance its rigidity and prevent deformation. However, these measures result in a large gap between the battery module and the first plate 11, wasting space. Increasing the thickness of the first plate 11 to increase its rigidity would increase the weight of the battery pack, hindering lightweight design.

[0038] The battery pack provided in this embodiment of the invention provides a protrusion 223 on the first end face 221 of the outer shell 20 of the cell 2, which is supported and connected to the first plate 11 of the housing, and the second end face 222 is supported and connected to the second plate 12 of the housing. This allows the outer shell 20 of the cell 2 to act as a supporting member between the first plate 11 and the second plate 12, preventing the first plate 11 from deforming significantly under impact. This reduces the thickness of the first plate 11 and the weight of the battery pack, which is beneficial for lightweight design. Furthermore, it reduces the distance between the busbar 3 and the first plate 11 without compressing the busbar 3 and the terminal post 23, thereby increasing the volume of the cell 2 and making full use of the space inside the housing, thus improving the energy density of the battery pack. Meanwhile, by setting the distance between the convex 223 and the first plate 11 to be less than the distance between the busbar 3 and the first plate 11, the convex 223 serves as the main load-bearing part of the cell 2, protecting the busbar 3 and the terminal post 23, and improving the safety performance of the battery pack.

[0039] It should be noted that the battery cell 2 has two terminals 23, namely a positive terminal and a negative terminal. Optionally, both terminals 23 are disposed on the first end face 221. Alternatively, one terminal 23 is disposed on the first end face 221, and the other terminal 23 is disposed on the second end face 222. When the second end face 222 is also provided with a terminal 23, the second end face 222 may also have a protrusion 223 spaced apart from the terminal 23, and the second end face 222 is supported and connected to the second plate portion 12 through the protrusion 223. The distance between the protrusion 223 on the second end face 222 and the second plate portion 12 may also be less than the distance between the busbar 3 and the second plate portion 12.

[0040] like Figure 3 As shown, in some embodiments of the present invention, the distance between the first end face 221 and the first plate portion 11 in the direction perpendicular to the first end face 221 is H1, the thickness of the busbar 3 in the direction perpendicular to the first end face 221 is H2, and the height of the pole post 23 relative to the first end face 221 is H3, 0.1mm≤H1-H2-H3≤5mm.

[0041] H1-H2-H3 represent the distances between the busbar 3 and the first plate 11. If this distance is too small, the busbar 3, as the main load-bearing component, is prone to damage to its welds, deformation of the terminal blocks, and leakage of the terminal blocks 23. If this distance is too large, it is not conducive to the full utilization of the space inside the casing, affecting the volume of the cell 2 and the improvement of the energy density of the battery pack. Optionally, the distance between the busbar 3 and the first plate 11 is 0.1mm, 0.5mm, 1mm, 1.5mm, 2mm, 2.5mm, 3mm, 3.5mm, 4mm, 4.5mm, or 5mm.

[0042] Table 1: Battery pack pressure test results under different H1 values

[0043] Using a battery pack with H2 of 1 mm and H3 of 3.2 mm as the test object (see Cases 1-13 in Table 1), the battery pack was subjected to pressure tests under different H1 values, and the test results are shown in Table 1.

[0044] As shown in Table 1, when H1-H2-H3 < 0.1mm (see Case 1 in Table 1), the distance between busbar 3 and the first plate 11 is too small, the protrusion 223 does not bear any force and does not provide support. Busbar 3 and terminal post 23 serve as the main support components. After the battery pack is disassembled, busbar 3 deforms, and cell 2 fails the helium test. When 0.1mm ≤ H1-H2-H3 ≤ 5mm (see Cases 2-12 in Table 1), the protrusion 223 serves as the main support component. After the battery pack is disassembled, busbar 3 does not show significant deformation, and cell 2 passes the helium test. When H1-H2-H3 > 5mm (see Case 13 in Table 1), the protrusion 223 serves as the main support component. After the battery pack is disassembled, busbar 3 does not show significant deformation, and cell 2 passes the helium test. However, the height of the protrusion 223 is relatively high, which is not conducive to improving the volumetric energy density of the battery pack.

[0045] Furthermore, with 0.1mm≤H1-H2-H3≤5mm, battery packs with different H2 and H3 were used as test objects (see Cases 14~17 in Table 1). The test results all showed that the convex 223 served as the main support component. After the battery pack was disassembled, the busbar 3 did not show obvious deformation, and the cell helium test was passed.

[0046] like Figure 2 As shown, in some embodiments of the present invention, the side of the convex hull 223 away from the first end face 221 is the connecting surface 2231, and the connecting surface 2231 is supported and connected to the first plate portion 11. The number of convex hulls 223 is at least one, the total area of ​​the connecting surfaces 2231 of all convex hulls 223 is S1, the area of ​​the first end face 221 is S0, and 0.1≤S1 / S0≤0.9.

[0047] It should be noted that the area of ​​the first end face 221 is the sum of the length and width of the first end face 221 minus the area of ​​the through hole on it.

[0048] The connecting surface 2231 is the side of the protrusion 223 away from the first end face 221, and also the side of the protrusion 223 facing the first plate portion 11. The connecting surface 2231 is supported and connected to the first plate portion 11, bearing the load transmitted by the first plate portion 11. In this embodiment, by setting the total area S1 of the connecting surfaces 2231 of all the protrusions 223 to between 0.1 and 0.9 times the area of ​​the first end face 221, the overall support strength of all the protrusions 223 can be guaranteed. If S1 is set too small, the overall support capacity of the protrusions 223 will be insufficient, and the ability to resist impact and vibration will be insufficient; if S1 is set too large, there will be insufficient space left for the installation of the pole post 23 and the explosion-proof valve 24, affecting the design of the pole post and the explosion-proof valve.

[0049] In some embodiments of the present invention, the area of ​​the connecting surface 2231 is S1', where S1' ≥ 10 mm. 2 That is, the area of ​​the connecting surface 2231 of a single convex hull 223 is at least 10 mm.2 This ensures the support strength of a single convex hull 223 and reduces the risk of deformation of a single convex hull 223 under local pressure.

[0050] Table 2: Results of battery pack vibration and shock tests under different S1 and S1' conditions

[0051] With S0 as 10000mm 2 The battery pack was used as the test object (see Cases 1-12 in Table 2). Vibration and shock tests were conducted on the battery pack with different values ​​of S1 and S1'. The test results are shown in Table 2.

[0052] As shown in Table 2, when S1 / S0 < 0.1 (see Case 2 in Table 2), busbar 3 deforms after the battery pack vibration and shock test. When 0.1 ≤ S1 / S0 ≤ 0.9 (see Cases 3-11 in Table 2), neither the convex pack 223 nor busbar 3 deforms after the battery pack vibration and shock test, and cell 2 passes the helium test. When S1 / S0 > 0.9 (see Case 12 in Table 2), neither the convex pack 223 nor busbar 3 deforms after the battery pack vibration and shock test, and cell 2 passes the helium test, but it has a significant impact on the design of terminal post 23 and explosion-proof valve 24.

[0053] When S1'≥10mm 2 When (see Cases 2-16 in Table 2), no deformation was observed in convex 223 during the vibration and impact test. When S1' < 10 mm 2 At that time (see Case 1 in Table 2), the convex hull 223 deformed during the vibration and impact test.

[0054] Furthermore, with 0.1≤S1 / S0≤0.9, battery packs with different S0 and S1 were used as test objects (see Cases 13~16 in Table 2). The results showed that after the battery pack vibration and shock test, the convex 223 and busbar 3 did not deform, and the cell 2 passed the helium test.

[0055] Furthermore, the connecting surface 2231 of the convex hull 223 is provided with reinforcing ribs to improve the structural strength of the convex hull 223.

[0056] like Figure 7 As shown, in some embodiments of the present invention, the connecting surface 2231 is bonded and fixed to the first plate portion 11 by adhesive 4, so that multiple battery cells 2 in the housing can be connected into a whole through the first plate portion 11, and a heat-conducting connection is formed between the convex bulge 223 and the first plate portion 11.

[0057] The total area of ​​all connecting surfaces 2231 is S1, and the total area of ​​adhesive 4 on all connecting surfaces 2231 is S2. S2 / S1≥0.5, meaning the total area of ​​adhesive 4 on all connecting surfaces 2231 is at least 0.5 times the total area of ​​connecting surfaces 2231 of all protrusions 223. This ensures the bonding strength between the battery module and the first plate 11, preventing adhesive layer cracking under impact and vibration. It also helps ensure stable contact between each protrusion 223 and the first plate 11, allowing the load acting on the first plate 11 to be transferred to each protrusion 223, preventing damage to the battery cell 2 due to excessive local pressure. Furthermore, it helps ensure the heat conduction area between the battery module and the first plate 11, guaranteeing the heat dissipation performance of the battery pack.

[0058] Furthermore, the area of ​​the adhesive 4 on each connecting surface 2231 is S2', and S2' / S1'≥0.5. This ensures reliable bonding between the individual protrusion 223 and the first plate portion 11, while also ensuring the contact area between the individual protrusion 223 and the first plate portion 11, which is beneficial for load and heat transfer.

[0059] Based on the above embodiment, the thickness of the adhesive layer between the connecting surface 2231 and the first plate portion 11 is T, where 0.5mm ≤ T ≤ 2mm. Optionally, the adhesive layer thickness T is 0.5mm, 0.8mm, 1mm, 1.2mm, 1.5mm, or 1.8mm. Since the protrusion 223 and the first plate portion 11 are insulatedly connected, an adhesive layer that is too thin can easily cause insulation failure; an adhesive layer that is too thick will occupy a large amount of internal space in the battery pack, which is not conducive to improving battery energy density, and instead of increasing adhesion, it will cause a decrease in thermal conductivity.

[0060] Table 3: Vibration and shock test results of battery packs under different S2 / S1, S2' / S1', and T conditions

[0061] With S1 as 1600mm 2 S1' is 400mm 2 The battery pack was used as the experimental object (see Cases 1-16 in Table 3). Vibration and shock tests were conducted on the battery pack with different values ​​of S2 and S2'. The experimental results are shown in Table 3.

[0062] As shown in Table 3, when S2 / S1 < 0.5 and S2' / S1' < 0.5 (see Case 1 in Table 3), the adhesive layer cracked after the battery pack vibration and impact test. When S2 / S1 ≥ 0.5 and S2' / S1' ≥ 0.5 (see Cases 2-16 in Table 3), the adhesive layer remained normal and did not crack after the battery pack vibration and impact test.

[0063] When S2 / S1≥0.5 and S2' / S1'≥0.5, and T<0.5mm (see Case 12 in Table 3), the insulation test fails after the battery pack vibration and shock test. When 0.5mm≤T≤2mm (see Cases 13~15 in Table 3), the insulation test passes after the battery pack vibration and shock test. When T>2mm (see Case 16 in Table 3), the insulation test passes after the battery pack vibration and shock test, but the adhesive layer is thicker, resulting in a significant increase in the weight and cost of the battery pack.

[0064] Furthermore, with S2 / S1 and S2' / S1' both greater than 0.5 and T being 1 mm, battery packs with different S1 and S1' were used as experimental subjects (see Cases 17-19 in Table 3). The experimental results all showed that after the battery pack vibration and shock test, the adhesive layer was normal and no cracks appeared, and the insulation test was passed.

[0065] like Figure 1 , Figure 3 and Figure 4 As shown in the embodiment of the invention, the battery cell 2 further includes an explosion-proof valve 24. Optionally, the explosion-proof valve 24 is disposed on the first end face 221, and the terminal post 23, the explosion-proof valve 24, and the protrusion 223 are arranged along the length direction of the first end face 221, with the protrusion 223 between the terminal post 23 and the explosion-proof valve 24. In this embodiment, the protrusion 223 separates the terminal post 23 and the explosion-proof valve 24. The protrusion 223 can be used to prevent the high-temperature gas discharged from the explosion-proof valve 24 from diffusing to the terminal post 23 and the busbar 3. In the event of thermal runaway of the battery cell 2, the protrusion 223 can also prevent the liquid sprayed from the explosion-proof valve 24 from splashing onto the terminal post 23 and the busbar 3, thereby achieving thermoelectric isolation and improving the safety of the battery pack.

[0066] There is a gap between the explosion-proof valve 24 and the first plate portion 11 to ensure that the gas inside the battery cell 2 can be discharged through the explosion-proof valve 24. The height of the explosion-proof valve 24 relative to the first end face 221 can be set to be less than the height of the protrusion 223 relative to the first end face 221, so as to ensure that there is a gap between the explosion-proof valve 24 and the first plate portion 11 when the side of the first plate portion 11 facing the first end face 221 is flat.

[0067] Furthermore, the distance between the explosion-proof valve 24 and the protrusion 223 is b, where b ≥ 10 mm. This prevents the protrusion 223 from affecting the opening pressure of the explosion-proof valve 24 when it acts as a load-bearing component.

[0068] In this embodiment of the invention, the number of protrusions 223 on the first end face 221 can be one or more. The number of protrusions 223 can be specifically determined according to the size of the first end face 221 and the volume and load-bearing capacity of the protrusions 223. When there are multiple protrusions 223, the first end face 221 is provided with multiple protrusions 223 arranged along its length direction; and / or, the first end face 221 is provided with multiple protrusions 223 arranged along its width direction. The dimensions of the multiple protrusions 223 in the length direction and / or width direction of the first end face 221 can be the same or different.

[0069] Based on the existing bulge 223 between the pole post 23 and the explosion-proof valve 24, bulges 223 can be installed at other locations as needed. A bulge 223 may be installed on the side of the pole post 23 furthest from the explosion-proof valve 24, or it may not be installed. A bulge 223 may be installed on the side of the explosion-proof valve 24 furthest from the pole post 23; see [reference needed]. Figure 4 The protrusion 223 may not be provided on the side of the explosion-proof valve 24 away from the pole post 23, see [reference]. Figure 3 .

[0070] In some embodiments of the present invention, a plurality of protrusions 223 are provided on the first end face 221 along its length direction. The explosion-proof valve 24 is located between two adjacent protrusions 223 along the length direction of the first end face 221. It is understood that at least two protrusions 223 are arranged on the first end face 221 along its length direction, wherein at least one protrusion 223 is located between the explosion-proof valve 24 and the pole post 23, and the other protrusions 223 are set according to actual needs.

[0071] See Figure 1 As a specific example, the first end face 221 is provided with two pole posts 23 and two protrusions 223. The two protrusions 223 are located between the two pole posts 23, and the explosion-proof valve 24 is located between the two protrusions 223, so as to realize the thermoelectric isolation between the explosion-proof valve 24 and the two pole posts 23.

[0072] See Figure 4 As a specific example, the first end face 221 is provided with two pole posts 23 and two protrusions 223. The two pole posts 23 are located on the same side of the two protrusions 223, and the explosion-proof valve 24 is located between the two protrusions 223. One of the protrusions 223 is used to prevent the material ejected by the explosion-proof valve 24 from reaching the pole post 23 of the battery cell 2, thereby achieving thermoelectric isolation of the battery cell 2 itself. In the case where multiple battery cells 2 are arranged along the length of the first end face 221 inside the housing, the other protrusion 223 can be used to prevent the material ejected by the explosion-proof valve 24 from reaching the adjacent battery cell 2, thereby achieving thermoelectric isolation between two adjacent battery cells 2.

[0073] In some embodiments of the present invention, at least a plurality of battery cells 2 are arranged along the width direction of the first end face 221 inside the housing, and the protrusions 223 of the plurality of battery cells 2 are arranged opposite to each other in the width direction of the first end face 221 to form a strip-shaped baffle.

[0074] Specifically, when there is only one protrusion 223 on the first end face 221, the protrusions 223 of multiple battery cells 2 arranged along the width direction of the first end face 221 are arranged to form a strip-shaped baffle. When there are multiple protrusions 223 arranged along the length direction of the first end face 221, the multiple protrusions 223 of multiple battery cells 2 arranged along the width direction of the first end face 221 are arranged one-to-one to form multiple strip-shaped baffles. The strip-shaped baffles can effectively prevent the material ejected from the explosion-proof valve 24 from reaching the terminal post 23 and busbar 3 of the adjacent battery cell 2, and also play a role in guiding the exhaust gas.

[0075] Furthermore, when the explosion-proof valve 24 is located between two adjacent protrusions 223 along the length of the first end face 221, two strip-shaped baffles are formed on both sides of the explosion-proof valve 24 of the plurality of battery cells 2 arranged along the width of the first end face 221. An exhaust channel is defined between the two strip-shaped baffles, the first end face 221, and the first plate portion 11, and the gas discharged from the explosion-proof valve 24 can be discharged to the outside of the battery pack along this exhaust channel.

[0076] In related technologies, the explosion-proof valve 24 and the terminal post 23 are located at opposite ends of the battery cell 2, for example, the terminal post 23 is located at the top of the battery cell 2 and the explosion-proof valve 24 is located at the bottom of the battery cell 2. To ensure that the gas discharged from the explosion-proof valve 24 can be discharged outside the battery pack, an exhaust channel needs to be provided between the casing and the bottom of the battery cell 2. In this embodiment, the explosion-proof valve 24 and the terminal post 23 are located at the same end. The exhaust channel is formed between the first end face 221 and the first plate portion 11 by the protrusion 223 supported between the first end face 221 and the first plate portion 11. This eliminates the need for a separate exhaust channel, improving the space utilization within the casing, which is beneficial for increasing the volume of the battery cell 2 and improving the energy density of the battery pack.

[0077] In this embodiment of the invention, the protrusion 223 adjacent to the explosion-proof valve 24 is preferably rectangular, which provides good blocking effect against the material ejected from the explosion-proof valve 24. For protrusions 223 in other positions, they can be rectangular, circular, triangular, or rhomboid, etc., depending on requirements or available space.

[0078] In some embodiments of the present invention, two pole posts 23 are provided on the first end face 221. The two pole posts 23 are arranged along the length direction, and the bulge 223 and the explosion-proof valve 24 are both located between the two pole posts 23. See [reference needed] Figure 1That is, the side of the pole post 23 away from the explosion-proof valve 24 does not have a protrusion 223. The two pole posts 23 can be set close to the two ends of the first end face 221 in the length direction, so as to reserve a large space between the two pole posts 23 to set multiple or large-area protrusions 223, thereby improving the support strength.

[0079] In the battery pack structure, to facilitate the installation of the busbar 3, among the multiple battery cells 2 arranged along the width direction of the first end face 221, the polarities of the opposing terminals 23 of two adjacent battery cells 2 in the width direction of the first end face 221 are opposite, that is, the positive and negative terminals of two adjacent battery cells 2 are opposite to each other. To facilitate the dissipation of heat inside the battery pack, the explosion-proof valves 24 of the multiple battery cells 2 arranged along the width direction of the first end face 221 are also arranged opposite to each other in the width direction of the first end face 221, so that the multiple explosion-proof valves 24 can discharge along the designated exhaust channels.

[0080] like Figure 1 and Figure 2 As shown, in some embodiments of the present invention, two pole posts 23 are provided on the first end face 221, and the two pole posts 23 are arranged along the length direction of the first end face 221. The explosion-proof valve 24 is located at the center of the length direction of the first end face 221, and the two pole posts 23 are symmetrically arranged about the explosion-proof valve 24. It can be understood that a protrusion 223 is provided between the two pole posts 23 and the explosion-proof valve 24. The protrusions 223 on both sides of the explosion-proof valve 24 of the multiple battery cells 2 arranged in the width direction of the first end face 221 are arranged to form two strip-shaped baffles. An exhaust channel is defined between the two strip-shaped baffles, the first end face 221 and the first plate portion 11, and the gas discharged from the explosion-proof valve 24 of the multiple battery cells 2 can be discharged to the outside of the battery pack along the exhaust channel.

[0081] In this embodiment, the explosion-proof valve 24 is positioned at the center of the length direction of the first end face 221, and the two terminals 23 are symmetrically arranged about the explosion-proof valve 24, so that the polarity of the terminals 23 of each cell 2 can be set to be the same. Among the multiple cells 2 arranged along the width direction of the first end face 221, each pair of adjacent cells 2 is arranged at 180°, which ensures that the explosion-proof valves 24 of adjacent cells 2 are opposite each other and that the positive and negative terminals are opposite, thus facilitating heat dissipation of the battery pack and the setting of the busbar 3. At the same time, since there is no need to set up two types of cells 2 with opposite terminal polarities 23, the production of cells 2 is simplified and error-proofing is facilitated.

[0082] Furthermore, the first end face 221 is provided with a plurality of protrusions 223 arranged along its length direction. The explosion-proof valve 24 is located between two adjacent protrusions 223 in the length direction, and the two adjacent protrusions 223 on both sides of the explosion-proof valve 24 are symmetrically arranged about the explosion-proof valve 24. In this way, when multiple battery cells 2 are arranged along the width direction of the first end face 221, arranging each two adjacent battery cells 2 at 180°, it can also ensure that the two adjacent protrusions 223 on both sides of the explosion-proof valve 24 of the multiple battery cells 2 are arranged as two strip-shaped baffles.

[0083] Due to structural design requirements, the two terminals 23 of the battery cell 2 cannot be too close to the two ends of the first end face 221 along its length. If the two terminals 23 were placed close to the two ends, it would waste the length space of the first end face 221. Figure 3 and Figure 4 As shown, in some other embodiments of the present invention, the two pole posts 23 are disposed on the same side of the explosion-proof valve 24 and the protrusion 223, that is, the protrusion 223 is not disposed on the side of the two pole posts 23 away from the explosion-proof valve 24. In this case, one pole post 23 can be disposed closer to the end of the first end face 221, and a larger space can be reserved between the other pole post 23 and the other end of the first end face 221 for the placement of the protrusion 223 and the explosion-proof valve 24. Compared with the pole post 23, the protrusion 223 and the explosion-proof valve 24 can be closer to the end of the first end face 221, thereby increasing the space on the first end face 221 for the placement of the protrusion 223, which is beneficial to increasing the area of ​​the protrusion 223 and improving the support strength of the protrusion 223.

[0084] like Figure 3 As shown, in some embodiments of the present invention, the convex bulge 223 is located between the pole post 23 and the explosion-proof valve 24. It can be understood that all the convex bulges 223 on the first end face 221 are located between the pole post 23 and the explosion-proof valve 24. Specifically, the first end face 221 has a first end and a second end opposite to each other in its length direction. The explosion-proof valve 24 is disposed near the first end, the two pole posts 23 are disposed near the second end, and the convex bulges 223 are concentrated between the pole post 23 and the explosion-proof valve 24. This allows the two pole posts 23 and the explosion-proof valve 24 to be separated by a single convex bulge 223, which helps to increase the area of ​​the single convex bulge 223, thereby improving the supporting strength of the convex bulge 223.

[0085] Furthermore, the explosion-proof valve 24 is positioned near the first end of the first end face 221 along its length, and the distance between the explosion-proof valve 24 and the edge of the first end is 'a', where 'a' ≥ 4 mm. It can be understood that, while ensuring the area and support strength of the bulge 223, the minimum distance between the explosion-proof valve 24 and the edge of the first end face 221 is 4 mm. Since a hole needs to be drilled in the cover plate 22 of the battery cell 2 to install the explosion-proof valve 24, if the distance between the explosion-proof valve 24 and the edge of the first end is too small, the strength of the cover plate 22 near the explosion-proof valve 24 will be low, and the cover plate 22 will be prone to deformation, affecting the opening pressure of the explosion-proof valve 24.

[0086] like Figure 5 and Figure 6 As shown in the embodiment of the present invention, a plurality of battery cells 2 are arranged in the box along the length and width directions of the first end face 221. Any two adjacent battery cells 2 in the length direction are arranged in a mirror symmetrical arrangement about the plane of symmetry perpendicular to the length direction of the first end face 221.

[0087] See Figure 5 When the protrusion 223 is located on the pole post 23 and the explosion-proof valve 24, that is, when there is no protrusion 223 on the side of the explosion-proof valve 24 away from the pole post 23, the explosion-proof valves 24 on two adjacent cells 2 are side by side in the length direction of the first end face 221, and there is no protrusion 223 between the two explosion-proof valves 24. That is, the protrusion 223 between the explosion-proof valve 24 and the pole post 23 blocks the material ejected from the explosion-proof valve 24 from reaching the pole post terminal, and thermoelectric separation is achieved by the two rows of cells 2 as a whole.

[0088] See Figure 6 When the explosion-proof valve 24 is provided with a protrusion 223 on the side away from the pole post 23, that is, the first end face 221 is provided with a protrusion 223 near its first end, then the outermost protrusions 223 of two adjacent cells 2 in the length direction of the first end face 221 are side by side, and there are two protrusions 223 between the two explosion-proof valves 24. The substances ejected from the explosion-proof valve 24 can be blocked from reaching the adjacent cells 2 through these two protrusions 223, so as to realize the thermoelectric separation between the adjacent cells 2.

[0089] In some embodiments of the present invention, the convex bulge 223 has multiple layers of protrusions stacked in its protruding direction. The convex bulge 223 serves a supporting function and needs to reach a certain height. When the convex bulge 223 is formed by stamping a plate-like part, excessively high single stamping height can easily cause the plate to break or affect the structural strength of the convex bulge 223. This embodiment sets the convex bulge 223 as a multi-layered protrusion structure, which can be formed by multiple stamping processes. This reduces the height of a single stamping, thereby preventing plate breakage and ensuring the structural strength of the convex bulge 223.

[0090] In some embodiments of the present invention, the first plate portion 11 and the second plate portion 12 can be the shell structure of a housing. For example, one of the first plate portion 11 and the second plate portion 12 is the first shell of the housing, and the other is the second shell of the housing. The protrusion 223 is fitted with the first shell, and the second end face 222 is fitted with the second shell. The heat of the battery cell 2 is transferred to the housing shell through the protrusion 223 and the second end face 222. The housing shell is usually made of thermally conductive steel or aluminum. The heat of the battery cell 2 is transferred to the housing shell, and heat exchange occurs through convection between the housing and the outside air.

[0091] In other embodiments of the present invention, the first plate portion 11 includes a first housing and a first cold plate, the first cold plate being located between the first housing and the protrusion 223, and the protrusion 223 being in contact with the first cold plate. The second plate portion 12 includes a second housing and a second cold plate, the second cold plate being located between the second housing and a second end face 222, and the second end face 222 being in contact with the second cold plate. The first and second cooling plates can be any of a liquid cooling plate, a direct cooling plate, or a phase change material cold plate. The heat from the battery cell 2 can be transferred to the first and second cooling plates through the protrusion 223 and the second end face 222, improving the cooling effect on the battery pack.

[0092] like Figure 7 As shown, in some embodiments of the present invention, at least one of the convex foil 223 and the busbar 3 is bonded and fixed to the first plate portion 11 by adhesive 4. In this way, multiple battery cells 2 can be connected into a whole through the first plate portion 11, forming a thermally conductive connection between the convex foil 223 and / or the busbar 3 and the first plate portion 11. Specifically, as... Figure 2 As shown, the side of the convex bulge 223 away from the first end face 221 is the connecting surface 2231, and the connecting surface 2231 is bonded and fixed to the first plate portion 11 by adhesive 4. The side of the busbar 3 away from the pole post 23 is bonded and fixed to the first plate portion 11 by adhesive 4.

[0093] In some embodiments of the present invention, the convex bulge 223 and the first plate portion 11 are bonded and fixed together by structural adhesive. The structural adhesive has certain thermal conductivity, enabling stable fixing of the convex bulge 223 and the first plate portion 11, and also possesses high strength, capable of withstanding large loads and exhibiting excellent resistance to dynamic loads or impacts. The structural adhesive exhibits minimal deformation under long-term stress, which helps maintain effective support of the convex bulge 223 for the first plate portion 11, thereby protecting the busbar 3 and the terminal post 23.

[0094] In some embodiments of the present invention, the busbar 3 and the first plate portion 11 are bonded and fixed together by thermally conductive adhesive. The thermally conductive adhesive has high thermal conductivity and maintains stable performance over a wide temperature range. This facilitates the rapid transfer of heat from the battery cell 2 through the terminal post 23, the busbar 3, and the thermally conductive adhesive to the first plate portion 11. Simultaneously, the thermally conductive adhesive is deformable under low compressive force, reducing the force exerted by the first plate portion 11 on the busbar 3 and preventing excessive compression of the busbar 3 by the first plate portion 11.

[0095] In the case where the protrusion 223 is in direct contact with the first plate 11, i.e. the distance between the protrusion 223 and the first plate 11 is zero, the distance between the busbar 3 and the first plate 11 is greater than zero. At this time, the busbar 3 and the first plate 11 can be set as a gap, or they can be fixed by thermally conductive adhesive. Both methods can ensure that the load acting on the first plate 11 can be preferentially transferred to the outer casing 20 of the cell 2, so as to protect the busbar 3 and the terminal 23.

[0096] When both the convex shank 223 and the busbar 3 are bonded and fixed to the first plate 11 with adhesive 4, the distance between the convex shank 223 and the first plate 11 is less than the distance between the busbar 3 and the first plate 11, resulting in a thinner adhesive layer between the convex shank 223 and the first plate 11 than between the busbar 3 and the first plate 11. Alternatively, both the convex shank 223 and the busbar 3 can be connected to the first plate 11 using thermally conductive adhesive, which improves the thermal conductivity from the cell 2 to the first plate 11; or the convex shank 223 can be connected to the first plate 11 using structural adhesive, and the busbar 3 can be connected to the first plate 11 using thermally conductive adhesive. Both methods allow the load acting on the first plate 11 to be preferentially transferred to the outer casing 20 of the cell 2, thus protecting the busbar 3 and the terminal post 23.

[0097] In some embodiments of the present invention, a glue-free zone is provided on the first end face 221 surrounding the explosion-proof valve 24, and glue overflowing onto the outer periphery of the protrusion 223 and the manifold 3 is located outside the glue-free zone. The distance c from the outer periphery of the explosion-proof valve 24 along its radial direction is c≥3mm.

[0098] When the required adhesive area between the connecting surface 2231 or the busbar 3 and the first plate portion 11 is large, adhesive overflow may occur. Since both the convex 223 and the pole post 23 protrude from the first end face 221, an adhesive overflow groove can be formed between two adjacent convex 223s, between two adjacent busbars 3, or between adjacent convex 223s and busbars 3, which can be used to collect adhesive overflowing from the convex 223 or the busbar 3.

[0099] In this embodiment, a glue-free zone is provided on the first end face 221 surrounding the explosion-proof valve 24. Glue that overflows onto the outer periphery of the protrusion 223 and the manifold 3 is restricted outside the glue-free zone, that is, outside a range of at least 3mm around the outer periphery of the explosion-proof valve 24, to ensure that the glue does not cover the explosion-proof valve 24 and cause the explosion-proof valve 24 to be unable to open.

[0100] Optionally, the first end face 221 is provided with an annular baffle surrounding the explosion-proof valve 24, and the area enclosed by the annular baffle serves as a glue-free zone. The presence of the annular baffle reduces the precision required to control the amount of glue applied and ensures that excess glue does not cover the explosion-proof valve 24.

[0101] like Figure 8 As shown, in some embodiments of the present invention, the portion of the busbar 3 connected between two adjacent cells 2 is provided with a bending portion 31, and a groove is formed on the side of the bending portion 31 near the first plate portion 11.

[0102] The bend 31 on the busbar 3, located between two adjacent cells 2, serves as a buffer structure to resist the impact of the first plate 11 on the busbar 3, as well as the impact caused by the expansion of the cells 2. Simultaneously, by providing the bend 31, a certain length of the busbar 3 can be reserved. When the distance between two adjacent cells 2 increases, the bend 31 can be straightened to compensate for the increased distance, reducing the risk of the weld between the busbar 3 and the tab being torn and improving the reliability of the connection between the busbar 3 and the tab.

[0103] A groove is formed on the side of the bent portion 31 near the first plate portion 11, which can act as an overflow groove. During the process of fixing the manifold 3 and the first plate portion 11 with adhesive, the adhesive overflowing from the manifold 3 can be at least partially contained in the overflow groove, thereby reducing the risk of adhesive overflowing into the explosion-proof valve 24.

[0104] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A battery pack, characterized in that, include: The housing has a first plate portion and a second plate portion that are arranged opposite to each other; A battery cell, disposed within the housing, includes a housing and a terminal post. The housing has a first end face and a second end face facing away from each other. The first end face is provided with the terminal post and a protrusion. The terminal post and the protrusion are spaced apart on the first end face. The protrusion is supported and connected to the first plate portion. The second end face is supported and connected to the second plate portion. A busbar is connected to the pole and located between the pole and the first plate portion, wherein the distance between the convex bulge and the first plate portion is less than the distance between the busbar and the first plate portion.

2. The battery pack according to claim 1, characterized in that, The distance between the first end face and the first plate portion in the direction perpendicular to the first end face is H1, the thickness of the busbar in the direction perpendicular to the first end face is H2, and the height of the pole relative to the first end face is H3, 0.1mm≤H1-(H2+H3)≤5mm.

3. The battery pack according to claim 1, characterized in that, The side of the convex hull away from the first end face is the connecting surface, and the connecting surface is supported and connected to the first plate portion. The number of convex hulls is at least one, the total area of ​​the connecting surfaces of all the convex hulls is S1, the area of ​​the first end face is S0, and 0.1≤S1 / S0≤0.

9.

4. The battery pack according to claim 1, characterized in that, The side of the convex bulge furthest from the first end face is the connecting surface, which is supported and connected to the first plate portion. The area of ​​the connecting surface is S1', where S1' ≥ 10 mm. 2 .

5. The battery pack according to claim 1, characterized in that, The battery cell also includes an explosion-proof valve, which is disposed on the first end face. The electrode post, the explosion-proof valve, and the convex bulge are arranged along the length direction of the first end face, and the convex bulge is provided between the electrode post and the explosion-proof valve.

6. The battery pack according to claim 5, characterized in that, The distance between the explosion-proof valve and the convex bulge is b, where b ≥ 10 mm.

7. The battery pack according to claim 1, characterized in that, The first end face is provided with a plurality of said protrusions arranged along its length direction, and / or the first end face is provided with a plurality of said protrusions arranged along its width direction.

8. The battery pack of claim 1, wherein, The convex hull has multiple layers of protrusions stacked in its convex direction.

9. The battery pack of claim 1, wherein, The first plate portion includes a first housing and a first cold plate, the first cold plate being located between the first housing and the protrusion, the protrusion being in contact with the first cold plate; The second plate portion includes a second housing and a second cold plate, the second cold plate being located between the second housing and the second end face, and the second end face being in contact with the second cold plate.

10. The battery pack of claim 1, wherein, At least one of the convex bulge and the busbar is fixed to the first plate portion by adhesive bonding.

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