Battery cell cover plate with force bearing function and battery

Abstract

The invention relates to the technical field of battery production, and provides a battery cell cover plate with a force bearing function and a battery. The negative pole and the positive pole are arranged at two ends of the outer surface of the cell cover plate along a first direction, and the first direction is the length direction of the cell cover plate; the plurality of bosses are arranged on the outer surface of the battery cell cover plate along the second direction and are used for bearing the structural stress of the battery module or the battery pack; the plurality of bosses are arranged between the negative pole and the positive pole at intervals in the first direction, the heights of the bosses in the second direction are consistent, the heights of the positive pole and the negative pole in the second direction are smaller than those of the bosses, and the second direction is the thickness direction of the battery cell cover plate; the step is arranged at the edge of the periphery of the battery cell cover plate and is used for abutting against the top end surface of the battery cell shell; according to the invention, the boss becomes the highest bearing structure of the outer surface of the cover plate, so that the potential safety hazard of the battery caused by the stress of the pole is avoided, the stress concentration of the welding area is reduced through the step, and the welding mark cracking is avoided.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of battery production, and in particular to a battery cell cover plate with a force bearing function and a battery. BACKGROUND

[0002] Lithium-ion power batteries have been widely used in new energy vehicles and other fields due to their high energy density and long cycle life. The structural reliability and space utilization rate of the batteries directly affect the overall performance of the battery module and the battery pack.

[0003] In the existing structure of lithium-ion power batteries, the highest point of the battery cell cover plate is usually the pole. In order to avoid the safety risks caused by the damage of the pole under stress, the battery cell is generally designed not to bear the structural force in the battery module or battery pack, and only relies on the external structure such as the module frame to bear the weight. However, this directly leads to low overall strength of the battery module or battery pack, and the structure is prone to deformation or even failure under mechanical impact in the height direction and other working conditions. SUMMARY

[0004] The present application provides a battery cell cover plate with a force bearing function and a battery to solve the defects of insufficient force bearing capacity of the battery cell cover plate and low overall strength of the battery cell in the prior art, and to improve the bearing capacity of the battery cell cover plate to the structural force of the battery module or battery pack.

[0005] In a first aspect, the present application provides a battery cell cover plate with a force bearing function, comprising: a positive pole; a negative pole, the negative pole and the positive pole being arranged at both ends of the outer surface of the battery cell cover plate along a first direction, the first direction being the length direction of the battery cell cover plate; a plurality of bosses arranged on the outer surface of the battery cell cover plate along a second direction for bearing the structural stress of the battery module or battery pack, the plurality of bosses being arranged at intervals along the first direction between the negative pole and the positive pole, the height of each boss along the second direction being uniform, and the height of the positive pole and the negative pole along the second direction being less than the height of the boss, the second direction being the thickness direction of the battery cell cover plate.

[0006] The battery cell cover plate with a force bearing function provided by the present application further comprises: a step arranged on the edge of the battery cell cover plate around for abutting against the top end surface of the battery cell shell.

[0007] The battery cell cover plate with a force bearing function provided by the present application further comprises: an aluminum plate, the boss and the step being arranged on the aluminum plate, both ends of the aluminum plate along the first direction being provided with a pair of electrode holes, the electrode holes being adapted to the positive pole or the negative pole.

[0008] The battery cell cover plate with force bearing function provided by the present application further comprises: The explosion-proof valve is arranged on the outer surface of the light aluminum plate and located between two adjacent bosses.

[0009] The boss has a rectangular cross section in the first direction, and the length L1 of the top surface of the boss and the length L of the light aluminum plate satisfy the relationship: 0.15L≤L1≤0.45L. In a third direction, the width W1 of the top surface of the boss and the width W of the battery cell cover plate satisfy the relationship: 0.45W≤L1≤0.85W, and the third direction is the width direction of the light aluminum plate.

[0010] The boss has a rectangular cross section in the first direction, and the length L1 of the top surface of the boss and the length L of the light aluminum plate satisfy the relationship: 0.15L≤L1≤0.45L.

[0011] The height T of the step in the second direction is between 0.45 mm and 1.2 mm, and the width D of the step in the first direction and the second direction is between 0.35 mm and 1.5 mm.

[0012] The battery cell cover plate with force bearing function provided by the present application further comprises: The connecting piece is arranged on the inner side of the light aluminum plate, one end of the connecting piece is used to extend into the battery cell shell corresponding to the inner side of the light aluminum plate and connect with the tab of the pole group, and the other end of the connecting piece is connected with the positive pole or the negative pole.

[0013] The inner side of the light aluminum plate is provided with a recess cavity corresponding to each boss, and the part of the connecting piece corresponding to the recess cavity is in a bent shape and accommodated in the recess cavity.

[0014] In a second aspect, the present application further provides a battery comprising: a battery cell shell and the battery cell cover plate as described in the first aspect, the battery cell cover plate is covered on the top of the battery cell shell, and the step of the peripheral edge of the battery cell cover plate abuts against the top end surface of the battery cell shell.

[0015] The application provides a battery cell cover plate with a bearing function, a plurality of bosses are arranged along the length direction of the cover plate at intervals between the negative pole column and the positive pole column on the outer surface of the battery cell cover plate, the boss is a protrusion along the thickness direction of the aluminum plate, which is equivalent to a reinforcing structure formed on the surface of the aluminum plate, and the height of the boss along the thickness direction of the aluminum plate is higher than that of the positive pole column and the negative pole column, so that the boss becomes the highest bearing structure on the outer surface of the cover plate, and the structural stress of the battery module or the battery pack is borne by the boss preferentially instead of directly acting on the pole column, thereby avoiding damage of the pole column caused by extrusion and collision under stress, preventing interference between the pole column and external components, ensuring the stable current conduction function of the pole column, and reducing the battery safety hazards such as liquid leakage and short circuit caused by the pole column failure. The step arranged around the periphery of the battery cell cover plate is in precise abutment with the top end face of the battery cell shell, which can position the assembly position of the battery cell cover plate and the battery cell shell, ensure the reliability and sealing performance of the connection between the battery cell cover plate and the battery cell shell, and make the battery cell shell share the stress of the welding area of the battery cell cover plate and the battery cell shell, eliminate the limitation that the force in the height direction is borne by the welding area alone in the traditional design, reduce the stress concentration of the welding area, avoid the cracking of the welding mark, and prolong the service life of the battery structure. BRIEF DESCRIPTION OF DRAWINGS

[0016] In order to more clearly illustrate the technical solutions in the application or the prior art, the following will briefly introduce the drawings needed to be used in the embodiments or the prior art description. Obviously, the drawings in the following description are some embodiments of the application, and other drawings can be obtained by those skilled in the art without any creative effort on the basis of these drawings.

[0017] Figure 1 is a front view of the battery cell cover plate provided by the embodiment of the application.

[0018] Figure 2 is Figure 1 is a sectional view along A-A direction in the embodiment.

[0019] Figure 3 is Figure 2 is a sectional view along B-B direction in the embodiment.

[0020] Figure 4 is Figure 3 is a local enlarged view of the embodiment.

[0021] Figure 5 is a schematic view of the inner side structure of the aluminum plate provided by the embodiment of the application.

[0022] Figure 6 is an axial side view of the battery provided by the embodiment of the application.

[0023] Reference signs: 1, positive post; 2, negative post; 3, boss; 4, step; 5, light aluminum plate; 6, explosion-proof valve; 7, connecting piece; 8, concave cavity; 9, lower plastic; 10, battery cell shell; 11, sealing element; 12, upper plastic; 13, liquid injection hole; 14, reinforcing rib; 15, post bottom plate. DETAILED DESCRIPTION

[0024] In order to make the objects, technical solutions and advantages of the present application clearer, the technical solutions in the present application will be clearly and completely described below with reference to the drawings in the present application. Obviously, the described embodiments are only some of the embodiments of the present application, but not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without creative work fall within the protection scope of the present application.

[0025] In the description of the embodiments of the present application, it should be noted that unless otherwise explicitly specified and limited, the terms "connected", "connected" should be understood in a broad sense, for example, it can be fixedly connected, or it can be detachably connected, or it can be integrally connected; it can be mechanically connected, or it can be electrically connected; it can be directly connected, or it can be indirectly connected through an intermediate medium. For those of ordinary skill in the art, the specific meaning of the above terms in the embodiments of the present application can be understood according to the specific circumstances.

[0026] In the description of the present application, the description of the terms "one embodiment", "some embodiments", "way", "specific way", or "some ways" means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or way are included in at least one embodiment or way of the embodiments of the present application. In the present application, the illustrative description of the above terms is not necessarily for the same embodiment or way. Moreover, the specific features, structures, materials or characteristics described can be combined in any appropriate way in any one or more embodiments or ways. In addition, those of ordinary skill in the art can combine and combine the different embodiments or ways described in the present application and the characteristics of different embodiments or ways without contradiction.

[0027] The following will be combined Figures 1-6 A battery cell cover plate with bearing function and a battery are described.

[0028] Referring to Figure 1The embodiment of the present application provides a battery cell cover plate with a bearing function, comprising: a positive pole 1, a negative pole 2, a plurality of bosses 3 and a step 4, wherein the negative pole 2 and the positive pole 1 are arranged at both ends of the outer surface of the battery cell cover plate along a first direction, the first direction is the length direction of the battery cell cover plate; a plurality of bosses 3 are arranged on the outer surface of the battery cell cover plate along a second direction, used for bearing the structural stress of the battery module or the battery pack; a plurality of bosses 3 are arranged between the negative pole 2 and the positive pole 1 along the first direction, and the height of the positive pole 1 and the negative pole 2 along the second direction is less than the height of the boss 3, the second direction is the thickness direction of the battery cell cover plate; the step 4 is arranged on the edge of the battery cell cover plate, used for abutting with the top end surface of the battery cell shell 10.

[0029] Through the above scheme, since the traditional battery cell cover plate has no special bearing structure, usually the positive and negative poles are the highest points of the outer surface of the cover plate, the present application arranges a plurality of bosses 3 between the negative pole 2 and the positive pole 1 of the outer surface of the battery cell cover plate along the length direction of the cover plate, the boss 3 is a protrusion along the thickness direction of the aluminum plate 5, which is equivalent to a reinforcing structure formed on the surface of the aluminum plate 5, and the height of the boss 3 along the thickness direction of the aluminum plate 5 is higher than that of the positive and negative poles 2, so that the boss 3 becomes the highest bearing structure of the outer surface of the cover plate, and the structural stress of the battery module or the battery pack is borne by the boss 3, rather than directly acting on the pole, avoiding damage of the pole caused by stress extrusion and collision, preventing interference between the pole and the external components, ensuring the stability of the current conduction function of the pole, and reducing the battery safety hazards such as liquid leakage and short circuit caused by the pole failure. The step 4 arranged on the edge of the battery cell cover plate is in precise abutment with the top end surface of the battery cell shell 10, which can position the assembly position of the battery cell cover plate and the battery cell shell 10, and ensure the connection reliability and sealing performance of the two; on the other hand, the abutment structure of the step 4 and the battery cell shell 10 makes the battery cell shell 10 share the stress of the welding area of the battery cell cover plate and the battery cell shell 10, eliminates the limitation that the force in the height direction is only borne by the welding area in the traditional design, reduces the stress concentration of the welding area, avoids the cracking of the welding mark, and prolongs the service life of the battery structure.

[0030] In some embodiments, the heights of all bosses 3 along the second direction are consistent, and the shapes and sizes of all bosses 3 are the same, by arranging the bosses 3 to have the same height along the thickness direction of the aluminum plate 5 and being higher than the heights of the positive and negative poles, the boss 3 becomes the highest bearing structure of the outer surface of the cover plate, and a plurality of support points with the same height and uniform distribution can be formed, when the battery cell is integrated into the module or the Pack, the pressure of the battery module and the Pack shell will act on the boss 3, and the plurality of bosses 3 bear the pressure synchronously, realizing uniform stress of multiple points, avoiding stress concentration in the local part of the cover plate, and significantly improving the bearing effect and sealing performance of the cover plate.

[0031] In this embodiment, the light aluminum plate 5 is also included, the boss 3 and the step 4 are arranged on the light aluminum plate 5, and a pair of electrode holes are arranged at two ends of the light aluminum plate 5 along the first direction, and the electrode holes are matched with the positive pole column 1 or the negative pole column 2.

[0032] As shown in Figure 1 the light aluminum plate 5 is a rectangular plate, and the explosion-proof valve 6 is arranged on the outer surface of the light aluminum plate 5 and located between the adjacent two bosses 3; in this way, the positive and negative poles are isolated from the explosion-proof valve 6 through the bosses 3, the heat is transferred to the explosion-proof valve 6 area by bypassing the surface of the light aluminum plate 5 between the bosses 3 when the electrode hole area generates high temperature due to large current, thereby prolonging the heat conduction path and avoiding the accumulation of electrode heat around the explosion-proof valve 6; when the explosion-proof valve 6 works, the high-temperature gas released by the explosion-proof valve 6 is limited in the independent space between the bosses 3, avoiding impacting the electrode hole area at both ends, and improving the safety of the power battery; thereby, through the design, the close-range conduction of the two types of hot spots is avoided, and the risk of accelerated aging of the material around the explosion-proof valve 6 and short circuit caused by the impact of high-temperature gas on the electrode when the explosion-proof valve 6 is relieved is eliminated from the root cause, and efficient hot spot separation is realized.

[0033] As preferred, the light aluminum plate 5 is an integral molding structure, and the cross section of the boss 3 is circular or rectangular, the integral molding structure avoids the weak joint area of the spliced light aluminum plate 5, which leads to subsequent force failure of the boss 3 or damage of the cover plate sealing; and the integral molding process forms a seamless whole structure of the light aluminum plate 5, the boss 3 and the electrode hole peripheral structure, without local stress overload risk, and ensures that the light aluminum plate 5 as a whole does not deform or break when the boss 3 bears the vibration and extrusion stress of the module or the battery pack.

[0034] As shown in Figure 1 in some embodiments, when the cross section of the boss 3 is rectangular along the first direction, the relationship between the length L1 of the top surface of the boss 3 and the length L of the light aluminum plate 5 along the first direction is 0.15L≤L1≤0.45L; and the relationship between the width W1 of the top surface of the boss 3 and the width W of the cover plate of the battery cell along the third direction is 0.45W≤L1≤0.85W, and the third direction is the width direction of the light aluminum plate 5.

[0035] Thus, the length L1 of the single boss 3 in the length direction of the light aluminum plate 5 is limited to 0.15L-0.45L, which avoids insufficient stress area caused by too small length of the single boss 3 and avoids occupying the installation space of key components such as the pole and the explosion-proof valve 6 caused by too large length of the single boss 3; in the width direction of the light aluminum plate 5, the width W1 of the single boss 3 is limited to 0.45W-0.85W, which can make the single boss 3 cover enough area in the width of the cover plate, ensure that the structural force of the battery module or the battery pack can be evenly transmitted to the boss 3, and avoid local stress concentration to cause deformation or fracture of the boss 3. Thus, through the size design of the boss 3, the idle area on the surface of the cell cover plate is fully utilized, the normal layout of other functional structures such as the explosion-proof valve 6, the pole and the electrolyte injection port is not affected, the interference between the boss 3 and the surrounding components is avoided, and the overall size of the cover plate does not need to be additionally expanded.

[0036] In some embodiments, the total area S1 of the top surface and the four surrounding side surfaces of the boss 3 and the total area S of the light aluminum plate 5 satisfy the relationship: 0.25S≤S1≤0.7S. Thus, the limitation of the size range ensures that the boss 3 has enough supporting area and can effectively disperse the structural force of the battery module or the battery pack, and also ensures that the boss 3 does not interfere with the layout of other functional structures while providing sufficient supporting force, which balances the load-bearing performance and space utilization efficiency.

[0037] As shown in Figure 3 , Figure 4 In the embodiment, the height T of the step 4 in the second direction is between 0.45mm and 1.2mm, and the width D of the step 4 in the first direction and the second direction is the same and is between 0.35mm and 1.5mm.

[0038] In the embodiment, a connecting piece 7 is further included, the connecting piece 7 is arranged on the inner side of the light aluminum plate 5, one end of the connecting piece 7 is used to extend into the cell shell 10 corresponding to the inner side of the light aluminum plate 5 and is connected with the tab of the pole group, and the other end of the connecting piece 7 is connected with the positive pole 1 or the negative pole 2.

[0039] Referring to Figure 5 , preferably, the inner side of the light aluminum plate 5 is provided with a recess 8 corresponding to the position of each boss 3, and the part of the connecting piece 7 corresponding to the recess 8 is in a bent shape and is accommodated in the recess 8.

[0040] Thus, the connecting piece 7 can be directly bent and embedded in the recess 8 from the tab, and then extended to the positive pole 1 or the negative pole 2 through the electrode hole at the corresponding position of the recess 8, so that the conductive length of the connecting piece 7 is directly shortened without additional winding or extension in the plane, and the space utilization rate inside the cover plate is improved, the design can reduce the current transmission loss and improve the fast charging efficiency and energy utilization efficiency of the cell.

[0041] AsFigure 5 As shown, the inner side of the light aluminum plate 5 is also provided with reinforcing ribs 14, for example, the reinforcing ribs 14 are arranged around the pole base plate 15 and the explosion-proof valve, which is used to improve the structural strength of the key structural position of the light aluminum plate 14, and is conducive to improving the overall bearing effect of the light aluminum plate 5.

[0042] In this embodiment, a lower plastic 9 is also included, which is arranged on the inner side of the light aluminum plate 5 and between the light aluminum plate 5 and the connecting piece 7. The lower plastic 9 is arranged between the positive pole 1 and the negative pole 2 along the first direction, and the part of the lower plastic 9 corresponding to the recessed cavity 8 is in a bent shape and is accommodated in the recessed cavity 8.

[0043] In this way, since the light aluminum plate 5 is of metal material and has conductivity, the connecting piece 7 serves as a conductive carrier of the positive and negative poles, and the lower plastic 9 is located between the light aluminum plate 5 and the connecting piece 7, which avoids direct electrical contact between the light aluminum plate 5 and the connecting piece 7 through its own insulation, ensures the transmission of current along the path of the tab, the connecting piece 7 to the busbar, and avoids the battery cell failure caused by abnormal conduction.

[0044] In some embodiments, a pair of electrode holes are symmetrically distributed on the light aluminum plate 5, and the explosion-proof valve 6 is arranged at the center of the light aluminum plate 5; two bosses 3 can be arranged, and the two bosses 3 are respectively arranged between the first electrode hole and the explosion-proof valve 6, and between the explosion-proof valve 6 and the second electrode hole.

[0045] In this way, the design of symmetrically distributing a pair of electrode holes and centrally arranging the explosion-proof valve 6 facilitates the symmetrical layout of the components inside the light aluminum plate 5, such as the lower plastic 9 and the connecting piece 7, which can avoid the problem of unilateral component crowding and the other side space idling in asymmetric design, and maximizes the utilization of the inner side space of the light aluminum plate 5; at the same time, it is conducive to the symmetrical consistency of the bending path of the connecting piece 7 corresponding to the positive and negative poles, and the consistency of the conductive path length, which can ensure the balanced distribution of the current of the positive and negative poles during charging and discharging, and balanced current transmission can reduce local overheating, combined with the above-mentioned hotspot separation design, to jointly improve the performance and long-term reliability of the battery cell.

[0046] As shown in the above-mentioned, Figure 1 , Figure 2 The injection hole 13 is arranged in one of the bosses 3 and penetrates the boss 3, and the injection hole 13 is used for injecting electrolyte into the battery cell shell 10; in this embodiment, the injection hole 13 is only arranged in one of the bosses 3, and after the through hole is arranged in the single boss 3, the remaining bosses 3 still maintain the complete bearing form, which can jointly bear the external stress and avoid the decline of the overall bearing capacity of the cover plate caused by the arrangement of the injection hole 13; at the same time, the cross section of the boss 3 has a certain area, and the diameter of the injection hole 13 is much smaller than the cross section size of the boss 3, which will not damage the mechanical structural integrity of the boss 3, and ensure that the boss 3 can still stably bear the vibration and extrusion stress of the module or the battery pack.

[0047] In the embodiment, the sealing member 11 is arranged at the connection between the connecting piece 7 and the electrode hole, and the upper plastic 12 is arranged on the outer surface of the aluminum plate 5 and is provided with a through hole matched with the positive pole 1 and the negative pole 2.

[0048] As shown in Figure 1 , Figure 2 , the positive pole 1 and the negative pole 2 extend to the outside of the aluminum plate 5 through the corresponding electrode holes, and there is a small gap between the poles and the walls of the electrode holes. The sealing member 11 is arranged at the connection between the poles and the electrode holes, and the sealing member 11 is compressed and deformed by its elastic material to fill the gap between the poles and the walls of the electrode holes, prevent the electrolyte from leaking out of the gap, and prevent external water vapor and dust from entering the inside of the battery shell 10 through the gap between the connecting piece 7 and the electrode hole, thereby ensuring the sealing property of the battery cover plate.

[0049] The upper plastic 12 can be fixed to the outer surface of the aluminum plate 5 by buckling or bonding. The upper plastic 12 is provided with a through hole matched with the poles at the position corresponding to the electrode hole. The poles extend to the outside through the through hole of the upper plastic 12 after passing through the electrode hole from the inside of the aluminum plate 5. The poles are embedded in the through hole of the upper plastic 12, and the positive pole 1 and the negative pole 2 are isolated from the aluminum plate 5 by the insulating property of the upper plastic 12, thereby blocking the abnormal conduction path. In addition, the upper plastic 12 can limit the poles in the radial direction from the outer circumferential side of the poles. During module assembly, the bus bar and the connecting piece 7 need to be accurately positioned for welding. The through hole of the upper plastic 12 can ensure that the positive pole 1 and the negative pole 2 do not deviate in the radial direction during the welding process, thereby ensuring the accuracy of the welding position.

[0050] Optionally, the upper plastic 12 and the lower plastic 9 are made of PP (polypropylene) material, which has excellent insulation and corrosion resistance. The upper plastic 12 isolates the welding block, the bus bar and the aluminum plate 5 from the outside of the aluminum plate 5, and the lower plastic 9 isolates the connecting piece 7 and the aluminum plate 5 from the inside of the aluminum plate 5, thereby blocking the abnormal conduction path between the inside and outside of the battery.

[0051] Referring to Figure 6 , the embodiment of the present application also provides a battery, which comprises a battery shell 10 and the battery cover plate described above. The battery cover plate is combined with the top of the battery shell 10, and the step 4 of the peripheral edge of the battery cover plate abuts against the top end surface of the battery shell 10.

[0052] The actual effect of the battery cover plate provided by the embodiment of the present application is verified through a plurality of test examples in combination with Table 1.

[0053] In the embodiment 1, the height T of the step 4 is 0.5 mm, satisfying 0.45 mm≤T≤1.2 mm, the width D of the step 4 is 0.35 mm, satisfying 0.35 mm≤D≤1.5 mm, and the ratio of the total area S1 of all the bosses 3 to the total area S of the light aluminum plate 5 is 25%, satisfying 0.25S≤S1≤0.7S. After actual processing test, the cell cover plate in the embodiment 1 can stably withstand stress without deformation, the welding mark at the connection between the cell shell 10 and the cell cover plate is not cracked, and the air tightness test also meets the requirements.

[0054] The parameter values of the embodiments 2 to 8 are shown in Table 1, which will not be repeated here.

[0055] In summary, in the embodiments 1-8, the parameters of the step 4 and the boss 3 are all valued according to the parameter range defined in the embodiment, and after actual processing test, finally, all the cell cover plates can stably withstand stress without deformation, and the welding mark at the connection between the cell shell 10 and the cell cover plate is not cracked, and the air tightness test also meets the requirements.

[0056] In the comparative example 1, the width D of the step 4 is 1.0 mm, satisfying 0.35 mm≤D≤1.5 mm, and the ratio of the total area S1 of all the bosses 3 to the total area S of the light aluminum plate 5 is 50%, satisfying 0.25S≤S1≤0.7S, but the height T of the step 4 is 0.35 mm, which is too small, finally resulting in insufficient overall strength of the cell, and the welding mark is cracked.

[0057] In the comparative example 2, the height T of the step 4 is 1.0 mm, satisfying 0.45 mm≤T≤1.2 mm, and the ratio of the total area S1 of all the bosses 3 to the total area S of the light aluminum plate 5 is 60%, satisfying 0.25S≤S1≤0.7S, but the width D of the step 4 is 0.25 mm, which is too small, finally also resulting in insufficient overall strength of the cell, and the welding mark is cracked.

[0058] In the comparative example 3, the height T of the step 4 is 1.0 mm, satisfying 0.45 mm≤T≤1.2 mm, the width D of the step 4 is 1.0 mm, satisfying 0.35 mm≤D≤1.5 mm, and the ratio of the total area S1 of all the bosses 3 to the total area S of the light aluminum plate 5 is 20%, which is too small, resulting in insufficient support area of the cover plate, finally also resulting in insufficient overall strength of the cell, and the welding mark is cracked.

[0059] It should be pointed out finally that the above embodiments are only used to illustrate the technical solutions of the present application, but not to limit the same; and although the present application has been described in detail with reference to the foregoing embodiments, it should be appreciated by those skilled in the art that the technical solutions recorded in the foregoing embodiments can be modified, or some technical features thereof can be replaced equivalently; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the spirit and scope of the technical solutions of the embodiments of the present application.

Claims

1. A battery cell cover plate with load-bearing function, characterized in that, include: Positive terminal (1); The negative electrode post (2) and the positive electrode post (1) are disposed at both ends of the outer surface of the cell cover plate along a first direction, the first direction being the length direction of the cell cover plate; Multiple protrusions (3) are disposed on the outer surface of the cell cover plate along the second direction to bear the structural stress of the battery module or battery pack; the multiple protrusions (3) are disposed at intervals between the negative electrode post (2) and the positive electrode post (1) along the first direction, and the height of each protrusion (3) along the second direction is the same, and the height of the positive electrode post (1) and the negative electrode post (2) along the second direction is less than the height of the protrusion (3), and the second direction is the thickness direction of the cell cover plate.

2. The battery cell cover plate with load-bearing function according to claim 1, characterized in that, Also includes: Steps (4) are provided around the edges of the cell cover plate to abut against the top end face of the cell housing (10).

3. The battery cell cover plate with load-bearing function according to claim 2, characterized in that, Also includes: The aluminum plate (5) has a boss (3) and a step (4) on it. The aluminum plate (5) has a pair of electrode holes at both ends along the first direction. The electrode holes are adapted to the positive electrode post (1) or the negative electrode post (2).

4. The battery cell cover plate with load-bearing function according to claim 3, characterized in that, Also includes: An explosion-proof valve (6) is disposed on the outer surface of the aluminum plate (5) and located between two adjacent bosses (3).

5. The battery cell cover plate with load-bearing function according to any one of claims 1-4, characterized in that, The protrusion (3) has a rectangular cross-section along the first direction. Along the first direction, the relationship between the length L1 of the top surface of a single protrusion (3) and the length L of the aluminum plate (5) is: 0.15L≤L1≤0.45L. Along the third direction, the relationship between the width W1 of the top surface of the boss (3) and the width W of the cell cover is: 0.45W≤L1≤0.85W, where the third direction is the width direction of the aluminum plate (5).

6. The battery cell cover plate with load-bearing function according to any one of claims 1-4, characterized in that, The relationship between the total area S1 of the top surface and the surrounding sides of the boss (3) and the total area S of the aluminum plate (5) is: 0.25S≤S1≤0.7S.

7. The battery cell cover plate with load-bearing function according to claim 3, characterized in that, The height T of the step (4) along the second direction is between 0.45 mm and 1.2 mm. The width D of the step (4) is the same along both the first and second directions, and is between 0.35 mm and 1.5 mm.

8. The battery cell cover plate with load-bearing function according to claim 3, characterized in that, Also includes: A connecting piece (7) is disposed on the inner side of the light aluminum plate (5). One end of the connecting piece (7) is used to extend into the cell housing (10) corresponding to the inner side of the light aluminum plate (5) and connect to the electrode tab of the electrode group. The other end of the connecting piece (7) is connected to the positive electrode post (1) or the negative electrode post (2).

9. The battery cell cover plate with load-bearing function according to claim 8, characterized in that, The inner side of the aluminum plate (5) is provided with a cavity (8) corresponding to the position of each of the protrusions (3), and the part of the connecting piece (7) corresponding to the cavity (8) is bent and accommodated in the cavity (8).

10. A battery, characterized in that, include: The battery cell housing (10) and the battery cell cover plate with load-bearing function as described in any one of claims 1-9, wherein the battery cell cover plate covers the top of the battery cell housing (10), and the steps (4) on the four periphery of the battery cell cover plate abut against the top end face of the battery cell housing (10).

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