Welding fixture and pre-welding equipment for single battery

Abstract

The utility model discloses a welding clamp and pre-welding equipment for a single battery, and belongs to the technical field of battery manufacturing, the single battery comprises an end cover and a shell with an opening, the end face of the end cover is provided with a protrusion, the end cover seals the opening in the first direction so that the protrusion can be sleeved with the shell, and the shell is arranged in the first direction. The welding clamp of the battery monomer comprises at least one pair of clamping assemblies, each pair of clamping assemblies comprises two clamping assemblies which are arranged at intervals in the second direction, each clamping assembly is provided with a first area and a second area, in the second direction, the first area protrudes out of the second area, the first area is used for abutting against a shell, and the second area is used for abutting against an end cover. The first direction is perpendicular to the second direction. According to the technical scheme provided by the invention, the gap between the shell and the bulge when the shell and the end cover are welded or pre-welded can be reduced, so that the sunken deformation of a welding seam is reduced, and the reliability of the single battery is improved.

Description

Technical Field

[0001] The present application relates to the technical field of battery manufacturing, and in particular to a welding fixture and pre-welding equipment for a battery cell. Background Art

[0002] At present, the batteries most commonly used in vehicles are generally lithium-ion batteries. As a rechargeable battery, lithium-ion batteries have the advantages of small size, high energy density, high power density, many cycles and long storage time.

[0003] A battery cell generally includes a shell, an end cover and an electrode assembly. The end face of the end cover has a protrusion. When the electrode assembly is accommodated in the shell and the opening of the shell is sealed by the end cover, the shell will be sleeved outside the protrusion. When welding or pre-welding the shell and the end cover, the gap between the shell and the protrusion causes the weld molten pool to flow toward the protrusion, which in turn causes a concave deformation in some areas of the weld, thereby reducing the connection strength between the shell and the end cover, thereby reducing the reliability of the battery cell. Utility Model Content

[0004] The embodiments of the present application provide a welding fixture and pre-welding equipment for a battery cell to reduce the gap between the shell and the protrusion when welding or pre-welding the shell and the end cover, thereby reducing the weld concave deformation and further improving the reliability of the battery cell.

[0005] In a first aspect, an embodiment of the present application provides a welding fixture for a battery cell, wherein the battery cell comprises an end cover and a shell having an opening, wherein an end face of the end cover has a protrusion, and the end cover seals the opening along a first direction so that the shell is sleeved outside the protrusion, and the welding fixture for the battery cell comprises at least one pair of clamping assemblies, each pair of the clamping assemblies is two arranged at intervals along a second direction, and the clamping assemblies have a first area and a second area, and along the second direction, the first area protrudes from the second area, the first area is used to abut against the shell, and the second area is used to abut against the end cover, and the first direction is perpendicular to the second direction.

[0006] In the above technical solution, since the first area protrudes beyond the second area along the second direction, when the first area abuts against the shell and the second area abuts against the end cover along the second direction, the second area will limit the movement of the end cover in the second direction, and the first area will drive part of the shell to elastically deform along the second direction, so that the shell is close to the protrusion, thereby reducing the gap between the shell and the protrusion in the second direction, so that when the shell and the end cover are pre-welded or welded, the molten pool formed by the melting of part of the shell and part of the end cover is used to fill the gap between the shell and the protrusion in the second direction. The part is reduced, thereby reducing the area of ​​the concave deformation region, thereby reducing the concave deformation of the weld, thereby reducing the stress concentration of the weld, thereby increasing the connection strength between the shell and the end cover, and improving the reliability of the battery cell.

[0007] In some embodiments, the first area and the second area are arranged sequentially along the first direction.

[0008] In the above technical solution, since the end cover covers the opening along the first direction, the first area and the second area are arranged in sequence along the first direction, which facilitates the first area and the second area to abut against the shell and the end cover respectively along the second direction, and the structure is simple and easy to implement.

[0009] In some embodiments, a dimension B of the first region protruding from the second region in the second direction satisfies 0 mm < B ≤ 0.2 mm.

[0010] In the above technical solution, when B>0mm, the first area can protrude from the second area in the second direction, so that when the second area restricts the end cover from moving in the second direction, the first area can drive the shell to elastically deform in the second direction; when B≤0.2mm, it can reduce the risk of excessive deformation of the shell caused by the first area, and reduce the risk of the end cover not being limited due to the second area not abutting against the end cover in the second direction when the first area drives the shell to abut against the protrusion; therefore, when 0mm<B≤0.2mm, it can not only meet the requirement that the first area can drive the shell to elastically deform, but also reduce the risk of excessive deformation of the shell caused by the first area, and reduce the risk of the end cover not being limited due to the second area not abutting against the end cover in the second direction when the first area drives the shell to abut against the protrusion.

[0011] In some embodiments, the clamping assembly includes a pressure strip; the pressure strip includes a plurality of first pressure teeth, the plurality of first pressure teeth are arranged at intervals along a third direction, and the sides of each pair of first pressure teeth of the clamping assembly arranged facing each other have the first area and the second area, and the first direction, the second direction and the third direction are perpendicular to each other.

[0012] In the above technical solution, multiple first pressure teeth are arranged at intervals along the third direction. On the one hand, it is convenient for the pressure strip to evenly provide supporting force to the shell and the end cover, thereby improving the reliability of the pressure strip limiting the shell and the end cover; on the other hand, it enables the pressure strip to provide extrusion force to the shell more evenly to drive uniform elastic deformation of the shell, which is beneficial to improving the quality of the weld; on the other hand, there is a gap between adjacent first pressure teeth to facilitate pre-welding by the welding gun, and the structure is simple and easy to implement.

[0013] In some embodiments, a distance between adjacent first pressing teeth in the third direction is L, satisfying 5mm≤L≤20mm.

[0014] In the above technical solution, when L>5mm, the two adjacent first pressing teeth can have a sufficient distance in the third direction for the structural parts of the welding mechanism to pass through, so as to facilitate the pre-welding of the shell and the end cover, and at the same time reduce the risk of the first pressing teeth being burned during pre-welding; when L≤20mm, the first pressing teeth can drive the elastic deformation of the shell more evenly, reducing the risk of the shell warping between adjacent first pressing teeth resulting in a larger gap between the shell and the protrusion; therefore, when 5mm≤L≤20mm, it can facilitate the pre-welding of the shell and the end cover, reduce the risk of the first pressing teeth being burned during pre-welding, and reduce the risk of the shell warping between adjacent first pressing teeth resulting in a larger gap between the shell and the protrusion.

[0015] In some embodiments, the pressure strip also includes a plurality of second pressure teeth; a plurality of the first pressure teeth and a plurality of the second pressure teeth are alternately arranged along the third direction, the second pressure teeth have a third area for abutting against the shell, and the third area is flush with the first area; along the first direction, the first pressure teeth protrude from the second pressure teeth.

[0016] In the above technical solution, the third area is flush with the first area, and along the first direction, the first pressing tooth protrudes from the second pressing tooth. On the one hand, the third area can press the shell between adjacent first pressing teeth, so that the first pressing tooth and the second pressing tooth can drive the shell to deform elastically more evenly, and further reduce the risk of warping of the shell between adjacent first pressing teeth, resulting in a larger gap between the shell and the protrusion; on the other hand, the first pressing tooth protrudes from the second pressing tooth, and then it is convenient to adjust the pressure strip in the first direction so that when the first pressing tooth presses the end cover, the second pressing tooth can avoid the connection between the shell and the end cover, thereby facilitating the pre-welding of the shell and the end cover.

[0017] In some embodiments, a dimension H of the first pressing tooth protruding from the second pressing tooth in the first direction satisfies 1 mm ≤ H ≤ 5 mm.

[0018] In the above technical solution, when L>1mm, when the first pressing tooth restricts the end cover, the second pressing tooth can have a certain distance from the weld in the first direction, thereby reducing the risk of the second pressing tooth being burned; when L≤5mm, the second pressing tooth can drive the shell close to the weld to elastically deform, thereby reducing the gap between the shell and the protrusion in the second direction, thereby reducing the area of ​​the concave deformation area, and improving the reliability of the battery cell; therefore, when 1mm≤H≤5mm, it can not only reduce the risk of the second pressing tooth being burned, but also reduce the gap between the shell and the protrusion in the second direction, thereby reducing the area of ​​the concave deformation area, and improving the reliability of the battery cell.

[0019] In some embodiments, the pressure bar further includes a pressure bar body, and the plurality of first pressure teeth are connected to the pressure bar body and protrude from the pressure bar body along a first direction.

[0020] In the above technical solution, multiple first pressing teeth are connected to the pressure strip body and protrude from the pressure strip body along the first direction, so that the multiple first pressing teeth are connected through the pressure strip body, thereby increasing the integrity of the pressure strip and facilitating the installation and disassembly of the pressure strip.

[0021] In some embodiments, along the second direction, the layering strip body has a fourth area connected to the first area, and the fourth area is flush with the first area; along the first direction, the first area is located between the second area and the fourth area.

[0022] In the above technical solution, the fourth area is flush with the first area, and along the first direction, the first area is located between the second area and the fourth area, so that the pressure strip body can also cooperate with the first pressure tooth to provide extrusion force to the shell, so that the shell can be elastically deformed more evenly in the second direction, thereby further reducing the risk of warping of the shell between adjacent first pressure teeth, resulting in a larger gap between the shell and the protrusion.

[0023] In some embodiments, the welding fixture of the battery cell also includes a mounting frame and at least one pair of first driving members; the clamping assembly is movably arranged on the mounting frame along the second direction; at least one pair of first driving members, two of the first driving members in each pair of the first driving members are configured to respectively drive the two of the clamping assemblies in each pair of the clamping assemblies to move closer to or away from each other along the second direction.

[0024] In the above technical solution, at least one pair of first driving members drives at least one pair of clamping assemblies to clamp the two sides of the battery cell in the second direction, so that the clamping device can limit the movement of the battery cell before the pre-welding process of the battery cell, and the structure is simple and easy to implement.

[0025] In some embodiments, the clamping assembly includes a pressure strip and a transmission member; the sides of the pressure strips of each pair of the clamping assemblies that are arranged opposite to each other have the first area and the second area; one end of the transmission member is connected to the first driving member, and the pressure strip is detachably mounted on the other end of the transmission member extending along the first direction.

[0026] In the above technical solution, the pressure strip is detachably mounted on the other end of the transmission member extending along the first direction to connect the pressure strip and the first driving member. On the one hand, it is convenient for the first driving member to drive the pressure strip to abut against the battery cell in the second direction; on the other hand, since the pressure strip is detachably mounted on the transmission member, it is convenient to replace different pressure strips according to the size of the battery cell shell and end cover, so that the clamping assembly can limit battery cells of different sizes, thereby increasing the scope of application of the clamping assembly.

[0027] In some embodiments, the clamping assemblies are a plurality of pairs spaced apart along a third direction, the first driving members correspond one-to-one to the clamping assemblies, and the first direction, the second direction and the third direction are perpendicular to each other.

[0028] In the above technical solution, the clamping assemblies are multiple pairs arranged at intervals along the third direction, and the first driving member corresponds to the clamping assemblies one by one, so that when the side wall of the shell in the second direction is not flat (such as the part of the side wall in the third direction is convex or concave relative to the other part along the second direction), the multiple pairs of clamping assemblies can respectively apply extrusion force to the shell to drive a more uniform elastic deformation of the shell.

[0029] In some embodiments, the battery cell welding fixture further includes a second driving member; the second driving member is configured to drive the clamping assembly to move along the first direction.

[0030] In the above technical solution, by configuring the second driving member to drive the clamping assembly to move along the first direction, it is convenient to adjust the clamping assembly in the first direction so that when the first area abuts the shell, the second area can abut the end cover. The structure is simple and easy to implement.

[0031] In a second aspect, an embodiment of the present application further provides a pre-welding device including a welding fixture for a battery cell as described in any embodiment of the first aspect. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings required for use in the embodiments will be briefly introduced below. It should be understood that the following drawings only show certain embodiments of the present application and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other related drawings can be obtained based on these drawings without paying creative work.

[0033] Figure 1 A cross-sectional view of a welding fixture for a battery cell provided in some embodiments of the present application;

[0034] Figure 2 A cross-sectional view of another battery cell welding fixture provided for some embodiments of the present application;

[0035] Figure 3 An exploded view of the structure of a battery cell provided in some embodiments of the present application;

[0036] Figure 4 A schematic diagram of the structure of a welding fixture for a battery cell provided in some embodiments of the present application;

[0037] Figure 5 for Figure 4 The enlarged view of point A in the middle;

[0038] Figure 6 A schematic diagram of the structure of the layering strips provided in some embodiments of the present application;

[0039] Figure 7 for Figure 6 The enlarged view of point B in the middle;

[0040] Figure 8 A schematic structural diagram of a welding fixture and a carrier for a battery cell provided in some embodiments of the present application.

[0041] Icon: 10- Welding fixture for battery cells;

[0042] 11-clamping assembly; 111-pressing strip; 111A-first body; 111B-second body; 1111-first pressing tooth; 1111A-first area; 1111B-second area; 1112-second pressing tooth; 1112A-third area; 1113-pressing strip body; 1113A-fourth area; 112-transmission member; 12-mounting frame; 121-platform; 13-first driving member; 14-second driving member;

[0043] 20 - battery cell; 21 - end cap; 211 - protrusion; 22 - housing; 221 - opening; 23 - electrode assembly;

[0044] 30- bearing member;

[0045] 40- welding gun;

[0046] X-first direction; Y-second direction; Z-third direction. DETAILED DESCRIPTION

[0047] In order to make the purpose, technical solution and advantages of the embodiments of the present application clearer, the technical solution in the embodiments of the present application will be clearly described below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of this application.

[0048] Unless otherwise defined, all technical and scientific terms used in this application have the same meanings as those commonly understood by technicians in the technical field of this application; the terms used in the specification of this application are only for the purpose of describing specific embodiments and are not intended to limit this application; the terms "including" and "having" in the specification and claims of this application and the above-mentioned drawings and any variations thereof are intended to cover non-exclusive inclusions. The terms "first", "second", etc. in the specification and claims of this application or the above-mentioned drawings are used to distinguish different objects, rather than to describe a specific order or a primary and secondary relationship.

[0049] Reference to "embodiment" in this application means that a particular feature, structure, or characteristic described in conjunction with the embodiment may be included in at least one embodiment of the present application. The appearance of the phrase in various places in the specification does not necessarily refer to the same embodiment, nor is it an independent or alternative embodiment that is mutually exclusive with other embodiments.

[0050] In the description of this application, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected", "connected", and "attached" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a direct connection, or an indirect connection through an intermediate medium, or it can be the internal communication of two elements. For ordinary technicians in this field, the specific meanings of the above terms in this application can be understood according to specific circumstances.

[0051] The term "and / or" in this application is only a description of the association relationship of associated objects, indicating that there can be three relationships. For example, A and / or B can represent: A exists alone, A and B exist at the same time, and B exists alone. In addition, the character " / " in this application generally indicates that the associated objects before and after are in an "or" relationship.

[0052] In the embodiments of the present application, the same reference numerals represent the same components, and for the sake of brevity, detailed descriptions of the same components are omitted in different embodiments. It should be understood that the thickness, length, width and other dimensions of various components in the embodiments of the present application shown in the drawings, as well as the overall thickness, length, width and other dimensions of the integrated device are only exemplary descriptions and should not constitute any limitation to the present application.

[0053] The term “plurality” used in this application refers to two or more (including two).

[0054] At present, from the perspective of market development, the application of power batteries is becoming more and more extensive. Power batteries are not only used in energy storage power systems such as hydropower, thermal power, wind power and solar power stations, but also widely used in electric vehicles such as electric bicycles, electric motorcycles, electric cars, as well as military equipment and aerospace and other fields. With the continuous expansion of the application field of power batteries, the market demand is also constantly expanding.

[0055] The battery cell includes a shell, an end cap and an electrode assembly, and the electrode assembly is accommodated in the shell. The shell has an opening, and the shell has a first wall facing away from the end cap. The end cap is used to cover the opening so that the end cap and the shell together form a storage space for accommodating the electrode assembly. Among them, a protrusion is provided on the end surface of the end cap facing the electrode assembly, and the protrusion is made of insulating material to insulate and isolate the electrode assembly and the end cap, so as to reduce the risk of internal short circuit in the battery cell. When the electrode assembly is accommodated in the shell and the opening of the shell is sealed by the end cap, the shell will be sleeved outside the protrusion. During the welding or pre-welding process of the end cap and the shell, due to the gap between the shell and the protrusion, the weld pool (part of the end cap material and part of the shell material melted in the molten pool) will flow toward the protrusion, thereby causing a concave deformation in some areas of the weld.

[0056] In order to improve the energy density of battery cells during the production process of battery cells, the thickness of the shell is thinned to reduce the volume of the battery cell occupied by the shell, so as to increase the volume of the electrode assembly. However, as the thickness of the shell becomes thinner, on the one hand, the melted material of the shell in the molten pool will be reduced, thereby reducing the thickness of the molten pool; on the other hand, the gap between the shell and the protrusion will become larger, thereby increasing the distance the molten pool flows toward the protrusion, thereby aggravating the concave deformation caused by the weld, making it easier for stress to concentrate at the weld, resulting in easy cracking at the weld, thereby reducing the connection strength between the shell and the end cover, thereby reducing the reliability of the battery cell.

[0057] Based on the above considerations, in order to reduce the gap between the shell and the protrusion when welding or pre-welding the shell and the end cover, thereby reducing the weld depression deformation and further improving the reliability of the battery cell, the present application embodiment provides a welding fixture and pre-welding equipment for a battery cell, wherein the welding fixture for the battery cell, the battery cell includes an end cover and a shell with an opening, the end face of the end cover has a protrusion, the end cover seals the opening along a first direction so that the shell is sleeved outside the protrusion, the welding fixture for the battery cell includes at least one pair of clamping assemblies, each pair of clamping assemblies is two arranged at intervals along a second direction, the clamping assembly has a first area and a second area, along the second direction, the first area protrudes from the second area, the first area is used to abut against the shell, the second area is used to abut against the end cover, and the first direction is perpendicular to the second direction.

[0058] In the welding fixture of the battery cell of this structure, since the first area protrudes beyond the second area along the second direction, when the first area abuts against the shell and the second area abuts against the end cover along the second direction, the second area will limit the movement of the end cover in the second direction, and the first area will drive part of the shell to elastically deform along the second direction, so that the shell is close to the protrusion, thereby reducing the gap between the shell and the protrusion in the second direction, so that when the shell and the end cover are pre-welded or welded, the molten pool formed by the melting of part of the shell and part of the end cover is used to fill the gap between the shell and the protrusion in the second direction. The area of ​​the concave deformation region is reduced, and the concave deformation of the weld is reduced, thereby reducing the stress concentration of the weld, thereby increasing the connection strength of the shell and the end cover, and improving the reliability of the battery cell.

[0059] The specific structures of the welding fixture and pre-welding equipment of the battery cell are described in detail below with reference to the accompanying drawings.

[0060] Please refer to Figure 1 and Figure 2 , and please refer to Figure 3 , Figure 1 and Figure 2 A cross-sectional view of two battery cell welding fixtures 10 provided in some embodiments of the present application, Figure 3An exploded view of the structure of a battery cell 20 provided in some embodiments of the present application. The embodiment of the present application provides a welding fixture 10 for a battery cell, wherein the battery cell 20 includes an end cover 21 and a shell 22 having an opening 221, wherein the end surface of the end cover 21 has a protrusion 211, and the end cover 21 seals the opening 221 along a first direction X so that the shell 22 is sleeved outside the protrusion 211, and the welding fixture 10 for the battery cell includes at least one pair of clamping assemblies 11, wherein each pair of clamping assemblies 11 is two arranged at intervals along a second direction Y, and the clamping assemblies 11 have a first area 1111A and a second area 1111B, wherein the first area 1111A protrudes from the second area 1111B along the second direction Y, and the first area 1111A is used to abut against the shell 22, and the second area 1111B is used to abut against the end cover 21, and the first direction X is perpendicular to the second direction Y.

[0061] The clamping assembly 11 is a component of the battery cell welding fixture 10 for abutting against the housing 22 and the end cover 21 of the battery cell 20 .

[0062] Each pair of clamping assemblies 11 is two and spaced apart along the second direction Y. It can be understood that at least one of each pair of clamping assemblies 11 can move relative to the other along the second direction Y to facilitate placing the battery cell 20 between each pair of clamping assemblies 11 .

[0063] In some embodiments, both clamping assemblies 11 in each pair of clamping assemblies 11 can move along the second direction Y. In some embodiments, one of the clamping assemblies 11 in each pair of clamping assemblies 11 is fixed in the second direction Y, and the other one can move along the second direction Y.

[0064] In some embodiments, the clamping assembly 11 is adjustably disposed on the ground along the second direction Y. In some embodiments, the battery cell welding fixture 10 further includes a mounting frame 12 , and the clamping assembly 11 is adjustably disposed on the mounting frame 12 along the second direction Y.

[0065] The first direction X is the direction in which the end cover 21 covers the housing 22, and the protrusion 211 protrudes from the side of the end cover 21 facing the housing 22 along the first direction X; the second direction Y is a direction perpendicular to the first direction X. Exemplarily, the first direction X may be the direction of gravity, and the second direction Y may be any horizontal direction; or the first direction X may be any horizontal direction, and the second direction Y may be the direction of gravity.

[0066] In some embodiments, each pair of clamping assemblies 11 has an open structure at both ends of the third direction Z, so that the battery cells 20 can be placed between each pair of clamping assemblies 11 through each pair of clamping assemblies 11 at both ends of the third direction Z. The first direction X, the second direction Y and the third direction Z are perpendicular to each other.

[0067] The first area 1111A and the second area 1111B may be two parts of the outer surface of one of each pair of clamping assemblies 11 facing the other along the second direction Y. Exemplarily, the first area 1111A may be in contact with the housing 22 along the second direction Y with a contact force to drive the housing 22 to elastically deform; the second area 1111B may be in contact with the end cover 21 along the second direction Y without a contact force; and the second area 1111B may be in contact with the end cover 21 along the second direction Y with a contact force.

[0068] In some embodiments, a portion of the outer surface of one of each pair of clamping components 11 facing the other along the second direction Y protrudes from the other portion along the second direction Y to form a convex portion, and the end surface of the convex portion facing the other clamping component 11 is the first area 1111A, and the non-convex portion of the outer surface is the second area 1111B.

[0069] In some embodiments, a portion of the outer surface of one of each pair of clamping components 11 facing the other along the second direction Y is recessed into the other portion along the second direction Y to form a groove, the bottom surface of the groove is the second area 1111B, and the non-groove portion of the outer surface is the first area 1111A.

[0070] It can be understood that the first area 1111A protrudes from the second area 1111B along the second direction Y. Therefore, when a pair of clamping components 11 respectively abut against the opposite sides of the battery cell 20 in the second direction Y, the first area 1111A will drive the shell 22 to elastically deform along the second direction Y, so that the shell 22 is recessed toward the direction close to the electrode assembly 23, and the gap between the shell 22 and the protrusion 211 along the second direction Y becomes smaller.

[0071] In the present embodiment, since the first region 1111A protrudes beyond the second region 1111B along the second direction Y, when the first region 1111A abuts against the shell 22 and the second region 1111B abuts against the end cover 21 along the second direction Y, the second region 1111B will limit the movement of the end cover 21 in the second direction Y, and the first region 1111A will drive part of the shell 22 to elastically deform along the second direction Y, so that the shell 22 is close to the protrusion 211, thereby reducing the gap between the shell 22 and the protrusion 211 in the second direction Y, so that when the shell 22 and the end cover 21 are pre-welded or welded, the molten pool formed by the melting of part of the shell 22 and part of the end cover 21 is used to fill the gap between the shell 22 and the protrusion 211 in the second direction Y. The area of ​​the concave deformation region is reduced, and the concave deformation of the weld is reduced, thereby reducing the stress concentration of the weld, thereby increasing the connection strength between the shell 22 and the end cover 21, and improving the reliability of the battery cell 20.

[0072] Please refer to Figure 1 and Figure 2According to some embodiments of the present application, the first region 1111A and the second region 1111B are arranged sequentially along the first direction X.

[0073] In some embodiments, please refer to Figure 1 , the first direction X is parallel to the direction of gravity, the end cover 21 is located below the shell 22, the clamping assembly 11 extends along the first direction X, and the first area 1111A is located above the second area 1111B, along the second direction Y, the shell 22 is located between a pair of clamping assemblies 11, and part of the end cover 21 is located between the pair of clamping assemblies 11.

[0074] In some embodiments, please refer to Figure 2 , the first direction X is parallel to the direction of gravity, the end cover 21 is located above the shell 22, the clamping assembly 11 extends along the first direction X, and the first area 1111A is located below the second area 1111B, along the second direction Y, part of the shell 22 is located between a pair of clamping assemblies 11, and the end cover 21 is located between the pair of clamping assemblies 11.

[0075] In this embodiment, since the end cover 21 covers the opening 221 along the first direction X, the first area 1111A and the second area 1111B are arranged in sequence along the first direction X, so that the first area 1111A and the second area 1111B are respectively abutted against the shell 22 and the end cover 21 along the second direction Y, and the structure is simple and easy to implement.

[0076] Please refer to Figure 1 and Figure 2 According to some embodiments of the present application, the first region 1111A protrudes from the second region 1111B in the second direction Y by a dimension B, satisfying 0mm<B≤0.2mm.

[0077] B can be any point value among 0.1mm, 0.2mm, 0.3mm, 0.4mm, 0.5mm, 0.6mm, 0.7mm, 0.8mm, 0.9mm, 1mm, 1.1mm, 1.2mm, 1.3mm, 1.4mm, 1.5mm, 1.6mm, 1.7mm, 1.8mm, 1.9mm, 2mm, etc., or a range value between any two of them.

[0078] In the present embodiment, when B>0 mm, the first area 1111A can protrude from the second area 1111B in the second direction Y, so that when the second area 1111B restricts the end cover 21 from moving in the second direction Y, the first area 1111A can drive the shell 22 to elastically deform in the second direction Y; when B≤0.2 mm, the risk of excessive deformation of the shell 22 caused by the first area 1111A can be reduced, and the risk of the shell 22 being brought into contact with the protrusion 211 by the first area 1111A can be reduced. The second area 1111B does not abut against the end cover 21 in the second direction Y, resulting in the risk of the end cover 21 not being limited. Therefore, when 0mm<B≤0.2mm, it can not only satisfy that the first area 1111A can drive the shell 22 to elastically deform, but also reduce the risk of excessive deformation of the shell 22 caused by the first area 1111A, and can also reduce the risk of the end cover 21 not being limited when the first area 1111A drives the shell 22 to abut against the protrusion 211, resulting in the second area 1111B not abutting against the end cover 21 in the second direction Y.

[0079] Please refer to Figure 4 and Figure 5 , Figure 4 This is a schematic diagram of the structure of a welding fixture 10 for a battery cell provided in some embodiments of the present application. Figure 5 for Figure 4 Enlarged view of A in the figure. According to some embodiments of the present application, the clamping assembly 11 includes a pressure strip 111. The pressure strip 111 includes a plurality of first pressure teeth 1111, and the plurality of first pressure teeth 1111 are arranged at intervals along the third direction Z. The side surfaces of each pair of first pressure teeth 1111 of the clamping assembly 11 facing each other have a first area 1111A and a second area 1111B, and the first direction X, the second direction Y and the third direction Z are perpendicular to each other.

[0080] The pressure strip 111 is a component in the clamping assembly 11 used to abut against the housing 22 and the end cover 21 of the battery cell 20 along the second direction Y.

[0081] The first pressing tooth 1111 is a portion of the pressing strip 111 used to abut against the housing 22 and the end cover 21 of the battery cell 20 along the second direction Y. Exemplarily, the first pressing tooth 1111 is in the shape of a strip extending along the first direction X. Exemplarily, the first pressing tooth 1111 of one of each pair of clamping assemblies 11 is provided with a first region 1111A and a second region 1111B on a side facing the other along the second direction Y.

[0082] In some embodiments, a side of the first pressing tooth 1111 facing the other clamping component 11 in the second direction Y is completely covered by the first region 1111A and the second region 1111B.

[0083] In some embodiments, a side of the first pressing tooth 1111 facing the other clamping component 11 in the second direction Y is partially covered by the first region 1111A and the second region 1111B.

[0084] It can be understood that the plurality of first pressing teeth 1111 are arranged at intervals along the third direction Z so as to provide gaps between adjacent first pressing teeth 1111 for the laser beam of the welding gun 40 to pass through.

[0085] In this embodiment, a plurality of first pressing teeth 1111 are arranged at intervals along the third direction Z. On the one hand, it is convenient for the pressure strip 111 to evenly provide supporting force to the shell 22 and the end cover 21, thereby improving the reliability of the pressure strip 111 limiting the shell 22 and the end cover 21; on the other hand, it enables the pressure strip 111 to more evenly provide extrusion force to the shell 22, so as to drive the shell 22 to evenly elastically deform, which is beneficial to improving the quality of the weld; on another hand, there is a gap between adjacent first pressure teeth 1111 to facilitate pre-welding by the welding gun 40, and the structure is simple and easy to implement.

[0086] Please refer to Figure 5 According to some embodiments of the present application, the distance between adjacent first pressing teeth 1111 in the third direction Z is L, satisfying 5mm≤L≤20mm.

[0087] L can be any point value among 5mm, 6mm, 7mm, 8mm, 9mm, 10mm, 11mm, 12mm, 13mm, 14mm, 15mm, 16mm, 17mm, 18mm, 19mm, 20mm, etc., or a range value between any two of them.

[0088] In this embodiment, when L>5mm, two adjacent first pressing teeth 1111 can have a sufficient distance in the third direction Z for the structural parts of the welding mechanism to pass through, so as to facilitate the pre-welding of the shell 22 and the end cover 21, and at the same time reduce the risk of the first pressing teeth 1111 being burned during pre-welding; when L≤20mm, the first pressing teeth 1111 can drive the shell 22 to elastically deform more evenly, reducing the risk of warping of the shell 22 between adjacent first pressing teeth 1111, resulting in a larger gap between the shell 22 and the protrusion 211; therefore, when 5mm≤L≤20mm, it is convenient for pre-welding the shell 22 and the end cover 21, reduces the risk of the first pressing teeth 1111 being burned during pre-welding, and reduces the risk of warping of the shell 22 between adjacent first pressing teeth 1111, resulting in a larger gap between the shell 22 and the protrusion 211.

[0089] Please refer to Figure 6 and Figure 7 , Figure 6 This is a schematic diagram of the structure of the pressure strip 111 provided in some embodiments of the present application. Figure 7 for Figure 6 Enlarged view of point B in the figure. According to some embodiments of the present application, the pressure strip 111 further includes a plurality of second pressing teeth 1112; the plurality of first pressing teeth 1111 and the plurality of second pressing teeth 1112 are alternately arranged along the third direction Z, the second pressing teeth 1112 have a third area 1112A for abutting against the housing 22, and the third area 1112A is flush with the first area 1111A; along the first direction X, the first pressing teeth 1111 protrude from the second pressing teeth 1112.

[0090] The second pressing teeth 1112 are another part of the pressing strip 111 for abutting against the housing 22 and the end cover 21 of the battery cell 20 along the second direction Y. Exemplarily, the second pressing teeth 1112 are strip-shaped extending along the first direction X. Exemplarily, the side of the second pressing teeth 1112 of one of each pair of clamping assemblies 11 facing the other along the second direction Y is provided with a third area 1112A.

[0091] In some embodiments, a side of the second pressing tooth 1112 facing the other clamping component 11 in the second direction Y is completely covered by the third area 1112A.

[0092] In some embodiments, a side of the second pressing tooth 1112 facing the other clamping component 11 in the second direction Y is partially covered by the third area 1112A.

[0093] In some embodiments, two ends of the third region 1112A in the first direction X are flush with two ends of the first region 1111A in the first direction X.

[0094] In some embodiments, two ends of the first region 1111A in the first direction X extend beyond two ends of the third region 1112A in the first direction X, respectively.

[0095] In this embodiment, the third area 1112A is flush with the first area 1111A, and along the first direction X, the first pressing tooth 1111 protrudes from the second pressing tooth 1112. On the one hand, the third area 1112A can press the shell 22 between adjacent first pressing teeth 1111, so that the first pressing teeth 1111 and the second pressing teeth 1112 can drive the shell 22 to elastically deform more evenly, and further reduce the risk of warping of the shell 22 between adjacent first pressing teeth 1111, resulting in a larger gap between the shell 22 and the protrusion 211; on the other hand, the first pressing tooth 1111 protrudes from the second pressing tooth 1112, and then it is convenient to adjust the pressure strip 111 in the first direction X so that when the first pressing tooth 1111 presses the end cover 21, the second pressing tooth 1112 can avoid the connection between the shell 22 and the end cover 21, thereby facilitating the pre-welding of the shell 22 and the end cover 21.

[0096] Please refer to Figure 7According to some embodiments of the present application, the dimension of the first pressing tooth 1111 protruding from the second pressing tooth 1112 in the first direction X is H, satisfying 1mm≤H≤5mm.

[0097] H can be any point value among 1mm, 1.1mm, 1.2mm, 1.3mm, 1.4mm, 1.5mm, 1.6mm, 1.7mm, 1.8mm, 1.9mm, 2mm, 2.5mm, 3mm, 3.5mm, 4mm, 4.5mm, 5mm, etc., or a range value between any two of them.

[0098] In the present embodiment, when L>1mm, when the first pressing tooth 1111 restricts the end cover 21, the second pressing tooth 1112 can have a certain distance from the weld in the first direction X, thereby reducing the risk of the second pressing tooth 1112 being burned; when L≤5mm, the second pressing tooth 1112 can drive the shell 22 close to the weld to elastically deform, thereby reducing the gap between the shell 22 and the protrusion 211 in the second direction Y, thereby reducing the area of ​​the concave deformation area, thereby improving the reliability of the battery cell 20; therefore, when 1mm≤H≤5mm, it can not only reduce the risk of the second pressing tooth 1112 being burned, but also reduce the gap between the shell 22 and the protrusion 211 in the second direction Y, thereby reducing the area of ​​the concave deformation area, thereby improving the reliability of the battery cell 20.

[0099] Please refer to Figure 6 and Figure 7 According to some embodiments of the present application, the pressure strip 111 further includes a pressure strip body 1113, and a plurality of first pressure teeth 1111 are connected to the pressure strip body 1113 and protrude from the pressure strip body 1113 along the first direction X.

[0100] The pressure strip body 1113 may be a portion of the pressure strip 111 that connects the first pressure tooth 1111 and other structural components of the clamping assembly 11 .

[0101] In an embodiment in which the pressure strip 111 and other structural parts of the clamping assembly are split, or in an embodiment in which the first pressure tooth 1111 and other structural parts of the pressure strip 111 are split, by connecting the pressure strip body 1113 and the first pressure tooth 1111 to connect multiple first pressure teeth 1111 and other structural parts, the installation of multiple pressure teeth and other structural parts can be completed more quickly, thereby reducing the processing time of the clamping assembly 11 and facilitating the installation and disassembly of the clamping assembly 11.

[0102] In some embodiments, the plurality of first pressing teeth 1111 and the plurality of second pressing teeth 1112 are connected to the pressure strip body 1113 , the plurality of first pressing teeth 1111 and the plurality of second pressing teeth 1112 are alternately arranged along the third direction Z and protrude from the pressure strip body 1113 along the first direction X.

[0103] In this embodiment, multiple first pressing teeth 1111 are connected to the pressure strip body 1113 and protrude from the pressure strip body 1113 along the first direction X, so that the multiple first pressing teeth 1111 are connected through the pressure strip body 1113, thereby increasing the integrity of the pressure strip 111 and facilitating the installation and disassembly of the pressure strip 111.

[0104] Please refer to Figure 6 and Figure 7 According to some embodiments of the present application, along the second direction Y, the layering body 1113 has a fourth area 1113A connected to the first area 1111A, and the fourth area 1113A is flush with the first area 1111A; along the first direction X, the first area 1111A is located between the second area 1111B and the fourth area 1113A.

[0105] In some embodiments, a side of the pressure strip body 1113 facing the other clamping assembly 11 in the second direction Y is completely covered by the fourth area 1113A.

[0106] In some embodiments, a side of the pressure strip body 1113 facing the other clamping assembly 11 in the second direction Y is partially covered by the fourth area 1113A.

[0107] In some embodiments, the fourth region 1113A is connected to both the first region 1111A and the third region 1112A, thereby facilitating one-time processing of the first region 1111A, the third region 1112A, and the fourth region 1113A.

[0108] In some embodiments, please refer to Figure 6 The pressure strip 111 includes a first body 111A and a second body 111B, which are stacked along the second direction Y. The first body 111A is used to connect with other structural members of the clamping assembly 11. The first body 111A can be made of metal materials (such as copper alloy, steel, aluminum alloy) to make the pressure strip 111 have a certain strength, and the second body 111B can be made of plastic (such as PEEK (polyetheretherketone), PEK (polyetherketone), PTFE (polytetrafluoroethylene) etc.) to reduce the risk of the pressure strip 111 scratching the housing 22 and the end cover 21. The first body 111A and the second body 111B are detachably connected.

[0109] In this embodiment, the fourth area 1113A is flush with the first area 1111A, and along the first direction X, the first area 1111A is located between the second area 1111B and the fourth area 1113A, so that the pressure strip body 1113 can also cooperate with the first pressure tooth 1111 to provide extrusion force to the shell 22, so that the shell 22 can be elastically deformed more evenly in the second direction Y, thereby further reducing the risk of warping of the shell 22 between adjacent first pressure teeth 1111, resulting in a larger gap between the shell 22 and the protrusion 211.

[0110] Please refer to Figure 4 , and please refer to Figure 8 , Figure 8 A schematic diagram of the structure of a welding fixture 10 and a carrier 30 for a battery cell provided in some embodiments of the present application. According to some embodiments of the present application, the welding fixture 10 for a battery cell further includes a mounting frame 12 and at least one pair of first driving members 13; the clamping assembly 11 is movably arranged on the mounting frame 12 along the second direction Y; at least one pair of first driving members 13, and the two first driving members 13 in each pair of first driving members 13 are configured to respectively drive the two clamping assemblies 11 in each pair of clamping assemblies 11 to move closer to or away from each other along the second direction Y.

[0111] In some embodiments, the welding fixture 10 of the battery cell further includes a mounting frame 12, and the mounting frame 12 includes a plurality of support rods (not shown in the figure) and a platform 121. The plurality of support rods are arranged at intervals and supported below the platform 121, and the plurality of support rods are evenly arranged at intervals along the outer periphery of the platform 121 to improve the uniformity of the force on the platform 121, and a first placement space is formed below the platform 121, and the first driving member 13 is arranged on the side of the platform 121 away from the first placement space, and the clamping assembly 11 is located in the first placement space and is connected to the first driving member 13 through the platform 121. The first placement space can be an open structure in the third direction Z so that the carrier 30 drives the battery cell 20 along the third direction Z to enter the first placement space and enter between a pair of clamping assemblies 11.

[0112] The first driving member 13 is a component that drives the clamping assembly 11 to abut against the battery cell 20 along the second direction Y. Exemplarily, the first driving member 13 may be a driving element such as an electric telescopic rod, a cylinder or a hydraulic cylinder.

[0113] In this embodiment, at least one pair of first driving members 13 drives at least one pair of clamping assemblies 11 to clamp the two side edges of the battery cell 20 in the second direction Y. This allows the clamping device to limit the movement of the battery cell 20 before the pre-welding process of the battery cell 20, and the structure is simple and easy to implement.

[0114] Please refer to Figure 4 , and please refer to Figure 8According to some embodiments of the present application, the clamping assembly 11 includes a pressure strip 111 and a transmission member 112; the sides of the pressure strip 111 of each pair of clamping assemblies 11 that are arranged opposite to each other have a first area 1111A and a second area 1111B; one end of the transmission member 112 is connected to the first driving member 13, and the pressure strip 111 is detachably mounted on the other end of the transmission member 112 extending along the first direction X.

[0115] The transmission member 112 is a component that connects the output end of the first driving member 13 with the pressure bar 111 .

[0116] In this embodiment, the pressure strip 111 is detachably mounted on the other end of the transmission member 112 extending along the first direction X to connect the pressure strip 111 and the first driving member 13. On the one hand, it is convenient for the first driving member 13 to drive the pressure strip 111 to abut against the battery cell 20 in the second direction Y; on the other hand, since the pressure strip 111 is detachably mounted on the transmission member 112, it is convenient to replace different pressure strips 111 according to the sizes of the shell 22 and the end cover 21 of the battery cell 20, so that the clamping assembly 11 can limit the battery cells 20 of different sizes, thereby increasing the scope of application of the clamping assembly 11.

[0117] Please refer to Figure 4 , and please refer to Figure 8 According to some embodiments of the present application, the clamping assemblies 11 are multiple pairs arranged at intervals along the third direction Z, the first driving members 13 correspond one-to-one to the clamping assemblies 11, and the first direction X, the second direction Y and the third direction Z are perpendicular to each other.

[0118] In this embodiment, the clamping assemblies 11 are multiple pairs arranged at intervals along the third direction Z, and the first driving members 13 correspond one-to-one to the clamping assemblies 11. Therefore, when the side wall of the shell 22 in the second direction Y is not a plane (such as a portion of the side wall in the third direction Z is convex or concave relative to another portion along the second direction Y), the multiple pairs of clamping assemblies 11 can respectively apply extrusion force to the shell 22 to drive a more uniform elastic deformation of the shell 22.

[0119] Please refer to Figure 4 , and please refer to Figure 8 According to some embodiments of the present application, the welding fixture 10 of the battery cell further includes a second driving member 14; the second driving member 14 is configured to drive the clamping assembly 11 to move along the first direction X.

[0120] In some embodiments, the second driving member 14 is disposed on a side of the platform 121 away from the first placement space, and the clamping assembly 11 is located in the first placement space and passes through the platform 121 to connect with the second driving member 14 .

[0121] The second driving member 14 is a component that drives the clamping assembly 11 to abut against the battery cell 20 along the first direction X. For example, the second driving member 14 may be a driving element such as an electric telescopic rod, a cylinder or a hydraulic cylinder.

[0122] In this embodiment, by configuring the second driving member 14 to drive the clamping assembly 11 to move along the first direction X, it is convenient to adjust the clamping assembly 11 in the first direction X so that when the first area 1111A abuts against the shell 22, the second area 1111B can abut against the end cover 21. The structure is simple and easy to implement.

[0123] The embodiment of the present application also provides a pre-welding device including a welding fixture 10 for a battery cell according to any one of the above embodiments.

[0124] According to some embodiments of the present application, referring to Figure 1-Figure 8The present application provides a welding fixture 10 for a battery cell. The battery cell 20 includes an end cover 21 and a shell 22 having an opening 221. The end surface of the end cover 21 has a protrusion 211. The end cover 21 covers the opening 221 along a first direction X so that the shell 22 is sleeved outside the protrusion 211. The welding fixture 10 for the battery cell includes at least one pair of clamping assemblies 11. Each pair of clamping assemblies 11 is two clamping assemblies arranged at intervals along a second direction Y. The clamping assemblies 11 have a first area 1111A and a second area 1111B. Along the second direction Y, the first area 1111A protrudes from the second area 1111B. The first area 1111A is used to abut against the shell 22, and the second area 1111B is used to abut against the end cover 21. The first direction X is perpendicular to the second direction Y. The first area 1111A and the second area 1111B are arranged in sequence along the first direction X. The dimension of the first area 1111A protruding from the second area 1111B in the second direction Y is B, satisfying 0mm<B≤0.2mm. The clamping assembly 11 includes a pressure strip 111. The pressure strip 111 includes a plurality of first pressing teeth 1111, and the plurality of first pressing teeth 1111 are arranged at intervals along the third direction Z. The sides of the first pressing teeth 1111 of each pair of clamping assemblies 11 facing each other have a first area 1111A and a second area 1111B, and the first direction X, the second direction Y and the third direction Z are perpendicular to each other. The distance between adjacent first pressing teeth 1111 in the third direction Z is L, satisfying 5mm≤L≤20mm. The pressure strip 111 also includes a plurality of second pressure teeth 1112; the plurality of first pressure teeth 1111 and the plurality of second pressure teeth 1112 are alternately arranged along the third direction Z, the second pressure teeth 1112 have a third area 1112A for abutting against the shell 22, and the third area 1112A is flush with the first area 1111A; along the first direction X, the first pressure teeth 1111 protrude from the second pressure teeth 1112. The dimension of the first pressure teeth 1111 protruding from the second pressure teeth 1112 in the first direction X is H, satisfying 1mm≤H≤5mm. The pressure strip 111 also includes a pressure strip body 1113, the plurality of first pressure teeth 1111 are connected to the pressure strip body 1113, and protrude from the pressure strip body 1113 along the first direction X. Along the second direction Y, the pressure strip body 1113 has a fourth region 1113A connected to the first region 1111A, and the fourth region 1113A is flush with the first region 1111A; along the first direction X, the first region 1111A is located between the second region 1111B and the fourth region 1113A. The welding fixture 10 for the battery cell further includes a mounting frame 12 and at least one pair of first driving members 13; the clamping assembly 11 is movably disposed on the mounting frame 12 along the second direction Y; at least one pair of first driving members 13, and the two first driving members 13 in each pair of first driving members 13 are configured to respectively drive the two clamping assemblies 11 in each pair of clamping assemblies 11 to move closer to or away from each other along the second direction Y.The clamping assembly 11 includes a pressure strip 111 and a transmission member 112; the side surfaces of the pressure strips 111 of each pair of clamping assemblies 11 facing each other have a first area 1111A and a second area 1111B; one end of the transmission member 112 is connected to the first drive member 13, and the pressure strip 111 is detachably mounted on the other end of the transmission member 112 extending along the first direction X. The clamping assemblies 11 are arranged in pairs at intervals along the third direction Z, and the first drive member 13 corresponds to the clamping assemblies 11 one by one. The welding fixture 10 of the battery cell also includes a second drive member 14; the second drive member 14 is configured to drive the clamping assembly 11 to move along the first direction X.

[0125] It should be noted that, in the absence of conflict, the embodiments and features in the embodiments of the present application may be combined with each other.

[0126] The above embodiments are only used to illustrate the technical solution of the present application and are not used to limit the present application. For those skilled in the art, the present application may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application shall be included in the protection scope of the present application.

Claims

1. A welding fixture for a battery cell, the battery cell comprising an end cover and a shell having an opening, the end surface of the end cover having a protrusion, the end cover sealing the opening along a first direction so that the shell is sleeved outside the protrusion, characterized in that: include: At least one pair of clamping assemblies, each pair of the clamping assemblies is two clamping assemblies arranged at intervals along a second direction, the clamping assemblies have a first area and a second area, along the second direction, the second area is used to abut against the end cover, the first area protrudes from the second area, the first area is used to abut against the shell, and the first direction is perpendicular to the second direction.

2. The battery cell welding fixture according to claim 1, characterized in that: The first area and the second area are arranged in sequence along the first direction.

3. The battery cell welding fixture according to claim 1, characterized in that: The first region protrudes from the second region in the second direction by a dimension B, which satisfies 0 mm < B ≤ 0.2 mm.

4. The battery cell welding fixture according to claim 1, characterized in that: The clamping assembly comprises: The pressure strip comprises a plurality of first pressure teeth, the plurality of first pressure teeth are arranged at intervals along a third direction, the sides of each pair of first pressure teeth of the clamping assembly facing each other have the first area and the second area, and the first direction, the second direction and the third direction are perpendicular to each other.

5. The battery cell welding fixture according to claim 4, characterized in that: A distance between adjacent first pressing teeth in the third direction is L, which satisfies 5mm≤L≤20mm.

6. The battery cell welding fixture according to claim 4, characterized in that: The layering strip also includes: a plurality of second pressing teeth, wherein the plurality of first pressing teeth and the plurality of second pressing teeth are alternately arranged along the third direction, and the second pressing teeth have a third area for abutting against the housing, and the third area is flush with the first area; Along the first direction, the first pressing tooth protrudes beyond the second pressing tooth.

7. The battery cell welding fixture according to claim 6, characterized in that: The first pressing tooth protrudes from the second pressing tooth in the first direction by a dimension H, which satisfies 1 mm ≤ H ≤ 5 mm.

8. The battery cell welding fixture according to claim 4, characterized in that: The pressure strip further comprises a pressure strip body, and the plurality of first pressure teeth are connected to the pressure strip body and protrude from the pressure strip body along a first direction.

9. The battery cell welding fixture according to claim 8, characterized in that: Along the second direction, the layering strip body has a fourth area connected to the first area, and the fourth area is flush with the first area; Along the first direction, the first region is located between the second region and the fourth region.

10. The battery cell welding fixture according to claim 1, characterized in that: The welding fixture of the battery cell also includes: A mounting frame, wherein the clamping assembly is movably disposed on the mounting frame along the second direction; At least one pair of first driving members, two of the first driving members in each pair of the first driving members are configured to respectively drive two of the clamping assemblies in each pair of the clamping assemblies to move closer to or farther from each other along the second direction.

11. The battery cell welding fixture according to claim 10, characterized in that: The clamping assembly comprises: A pressure strip, wherein the sides of the pressure strips of each pair of the clamping assemblies facing each other have the first area and the second area; A transmission member has one end connected to the first driving member, and the pressure strip is detachably mounted on the other end of the transmission member extending along the first direction.

12. The battery cell welding fixture according to claim 10, characterized in that: The clamping assemblies are multiple pairs arranged at intervals along the third direction, the first driving members correspond to the clamping assemblies one by one, and the first direction, the second direction and the third direction are perpendicular to each other.

13. The battery cell welding fixture according to claim 1, characterized in that: The welding fixture of the battery cell also includes: A second driving member is configured to drive the clamping assembly to move along the first direction.

14. A pre-welding device, characterized in that: A welding fixture comprising a battery cell as claimed in any one of claims 1 to 13.

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