CN220492141U - Novel welding structure of composite current collector - Google Patents

Abstract

The novel welding structure of the composite current collector comprises composite current collector layers and lugs, wherein the composite current collector layers are provided with a plurality of layers, each composite current collector layer is connected with a conductive foil piece, and adjacent conductive foil pieces are connected with each other and are electrically connected with the lugs; each composite current collecting layer comprises a first metal layer, a second metal layer and an insulating layer which are arranged in a stacked manner; the insulating layer is arranged between the first metal layer and the second metal layer; and a supporting piece is arranged between the conductive foil piece and the composite current collecting layer and is used for supporting the conductive foil piece. According to the welding structure of the composite current collector, the supporting piece for supporting the conductive foil piece is arranged in the structure formed by welding the composite current collector layer and the electrode lugs through the conductive foil, and the traction tension born by the foil can be reduced during welding, so that the shrinkage deformation of the foil is reduced; and the single composite current collecting layer and the conductive foil piece are welded into a composite welding unit, and each composite welding unit is welded with the electrode lug after being stacked up and down, so that the welding efficiency can be improved.

Description

Novel welding structure of composite current collector

Technical Field

The utility model relates to the field of lithium batteries, in particular to a novel welding structure of a composite current collector.

Background

The current collector refers to a structure or a part for collecting current, and is used for connecting the tabs and collecting the current generated by the active materials of the battery so as to form a larger current output. The composite current collector has the advantages of small thickness, high stability and the like, and is widely applied.

At present, the welding structure of the composite current collector generally adopts foil materials to connect a plurality of composite current collecting layers with the electrode lugs, and when in welding, the foil materials can shrink due to the influences of welding temperature, air flow and the like, and the foil materials are easy to deform, so that the shrinkage deformation of the foil materials after welding is more serious, and the defective rate is increased.

Therefore, the applicant has devised a novel welding structure of a composite current collector to solve the above-mentioned problems.

It should be noted that the foregoing description of the background art is only for the purpose of providing a clear and complete description of the technical solution of the present utility model and is presented for the convenience of understanding by those skilled in the art. The above-described solutions are not considered to be known to the person skilled in the art simply because they are set forth in the background of the utility model section.

Disclosure of Invention

In order to overcome the defects in the prior art, the utility model aims to provide a novel welding structure of a composite current collector.

To achieve the above and other related objects, the present utility model provides the following technical solutions: a novel welding structure of a composite current collector comprises a composite current collector layer and a tab,

the composite current collecting layers are provided with multiple layers, each composite current collecting layer is connected with one conductive foil piece, and adjacent conductive foil pieces are connected with each other and are electrically connected with the electrode lugs; each composite current collecting layer comprises a first metal layer, a second metal layer and an insulating layer which are arranged in a stacked manner; the insulating layer is arranged between the first metal layer and the second metal layer;

and a supporting piece is arranged between the conductive foil piece and the composite current collecting layer and is used for supporting the conductive foil piece.

In the scheme, a supporting piece is added in a structure formed by welding a composite current collecting layer and a pole lug through conductive foil materials, and the supporting piece is arranged between the conductive foil pieces and the composite current collecting layer, namely, the inner side of the conductive foil pieces, because both ends of the conductive foil pieces, which are connected up and down, of the composite current collecting layer are required to be welded, the conductive foil pieces and the conductive foil pieces are also required to be welded, the body of the conductive foil pieces is a foil material, the conductive foil pieces are easy to deform, and the supporting piece is internally provided with the supporting piece which can realize the supporting of the upper part, the lower part and the middle bending part of the conductive foil pieces; when the two ends of the conductive foil piece are welded, due to the influences of factors such as temperature and air flow, the foil above the supporting piece and the foil below the supporting piece are influenced, the existence of the supporting piece can reduce the traction tension born by the foil at the two parts, so that the shrinkage deformation of the foil during welding is reduced, the supporting piece supports the middle bending part of the conductive foil piece, the supporting piece plays a role in expanding when the conductive foil piece is bent, the problem of easy deformation of the conductive foil piece body can be solved, the deformation of the foil body is reduced, and the yield of the composite current collector is improved.

In an embodiment of the present application, the support member is disposed on a side of the composite current collecting layer connected to the conductive foil member, the conductive foil member is wrapped around the support member, two ends of the conductive foil member connected to the composite current collecting layer from top to bottom are respectively fixedly connected to the first metal layer and the second metal layer, and the composite current collecting layer, the support member and the conductive foil member together form a composite welding unit. In the scheme, one end of the composite current collecting layer is clamped by two ends of the conductive foil piece and welded and fixed, the conductive foil piece wraps the supporting piece in the composite current collecting layer, each point position in contact with the supporting piece can play a supporting role, the disadvantage that the foil material is easy to deform is balanced, the upper and lower bending deformation of the foil material can be prevented, and the deformation of the foil material can be reduced during welding; and the single composite current collecting layer and the conductive foil piece are welded into a composite welding unit, and each composite welding unit is welded with the electrode lug after being stacked up and down, so that the welding efficiency can be improved.

In an embodiment of the present application, the support member is a plate-shaped structure, the longitudinal length of the support member is not less than the longitudinal length of the composite current collector layer, the transverse length of the support member is greater than half of the transverse folded length of the conductive foil member, and the thickness of the support member is equal to the thickness of the composite current collector layer and the support member and the composite current collector layer are arranged in an up-down flush manner.

In the scheme, the longitudinal length of the supporting piece is not smaller than that of the composite current collecting layer, so that the supporting piece can be ensured to completely cover the supporting range required by the longitudinal direction of the conductive foil piece, and the supporting effect is ensured; the transverse length of the supporting piece is larger than half of the transverse folded length of the conductive foil piece, so that the transverse supporting coverage rate of the supporting piece on the conductive foil piece exceeds 50%, and the supporting stability can be better ensured; the thickness of the supporting piece is equal to that of the composite current collecting layer, the upper end face and the lower end face of the supporting piece can be respectively arranged in the same plane with the upper end face and the lower end face of the composite current collecting layer, after the two ends of the conductive foil piece are fixed with the composite current collecting layer, the supporting piece can keep stable in the upper position and the lower position, and the supporting piece can play a role in supporting better and more stable in effect.

In an embodiment of the present application, a cross section of an end of the supporting member, which is abutted against the bending portion of the conductive foil member, is circular arc.

In this scheme, support piece is used for supporting the position of conductive foil spare bending part, has set to convex, and the contact of the inside surface of bending part that can be better, convex holding surface compare other shapes such as square, and the atress of each point position is more even, can play better supporting role.

In an embodiment of the present application, a glue layer is disposed between the support member and the composite current collector layer.

In this scheme, make to be connected stably between support piece and the compound mass flow layer through scribbling the colloid, prevent in the welding of compound welding unit and the welding of whole compound mass flow body, the skew takes place for support piece's position, and the better support effect of support piece of assurance of glue film.

In an embodiment of the present application, the composite welding units are connected up and down through conductive foil pieces, and adjacent conductive foil pieces are electrically connected through upper and lower end face welding of each other, where one conductive foil piece is connected with the tab.

In this scheme, make independent compound welding unit with compound current collector layer and conductive foil spare earlier, pile up each compound welding unit from top to bottom the back through conductive foil spare welding again, with one of them conductive foil spare and utmost point ear welding again at last for realize electric connection between upper and lower looks two compound current collector layers, improved welded efficiency, also made welding operation more convenient.

In an embodiment of the present application, the conductive foil member is an aluminum foil or a copper foil.

In this scheme, electrically conductive foil spare can be the aluminium foil, also can be the copper foil, and both have better conductivity to and good ductility, can make the better laminating of foil and support piece for support piece plays better supporting role to the foil.

In an embodiment of the present application, the material of the support member is ceramic or carbon fiber.

In this scheme, adopt ceramic or carbon fiber, both are insulating hard material, are difficult for buckling, can play effectual supporting role.

Due to the application of the technical scheme, compared with the prior art, the utility model has the following beneficial effects:

1. according to the utility model, the support piece for supporting the conductive foil piece is arranged in the structure formed by welding the composite current collecting layer and the electrode lugs through the conductive foil, and the traction tension applied to the foil can be reduced during welding, so that the contraction deformation of the foil is reduced.

2. According to the utility model, a single composite current collecting layer and the conductive foil piece are welded into the composite welding unit, and each composite welding unit is stacked up and down and then welded with the electrode lug, so that the welding efficiency can be improved.

3. The utility model designs a close fitting structure between the supporting piece and the conductive foil piece, and each point of contact is uniformly stressed, so that the supporting effect is good, and the welding deformation of the conductive foil piece is reduced.

Drawings

FIG. 1 is a schematic diagram of an embodiment of the present utility model;

FIG. 2 is a schematic diagram of a hybrid welding unit according to an embodiment of the present utility model;

FIG. 3 is a schematic diagram of an embodiment of the present utility model;

in the above drawings, 1, a composite current collecting layer; 101. a first metal layer; 102. a second metal layer; 103. an insulating layer; 2. a tab; 3. a conductive foil member; 301. an upper connection part; 302. a bending part; 303. a lower connecting part; 4. a composite welding unit; 5. a support; 6. and (5) a glue layer.

Detailed Description

Further advantages and effects of the present utility model will become apparent to those skilled in the art from the disclosure of the present utility model, which is described by the following specific examples.

It should be noted that, in the description of the present utility model, it should be noted that, directions or positional relationships indicated by terms such as "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc., are directions or positional relationships based on those shown in the drawings, or directions or positional relationships in which the inventive product is conventionally put in use, are merely for convenience of describing the present utility model and for simplifying the description, and are not indicative or implying that the apparatus or element to be referred to must have a specific direction, be constructed and operated in a specific direction, and therefore should not be construed as limiting the present utility model. Furthermore, the terms "first," "second," "third," and the like are used merely to distinguish between descriptions and should not be construed as indicating or implying relative importance. The terms "horizontal," "vertical," "overhang," and the like do not denote that the component is required to be absolutely horizontal or overhang, but may be slightly inclined. As "horizontal" merely means that its direction is more horizontal than "vertical", and does not mean that the structure must be perfectly horizontal, but may be slightly inclined.

In the description of the present utility model, it should also be noted that, unless explicitly specified and limited otherwise, the terms "disposed," "mounted," "connected," and "connected" are to be construed broadly, and may be, for example, fixedly connected, detachably connected, integrally connected, mechanically connected, electrically connected, directly connected, indirectly connected through an intermediary, or communicating between two elements. The specific meaning of the above terms in the present utility model will be understood in specific cases by those of ordinary skill in the art.

In the description of the present application, it should be understood that, where azimuth terms such as "front, rear, upper, lower, left, right", "transverse, vertical, horizontal", and "top, bottom", etc., indicate azimuth or positional relationships generally based on those shown in the drawings, only for convenience of description and simplification of the description, these azimuth terms do not indicate and imply that the apparatus or elements referred to must have a specific azimuth or be constructed and operated in a specific azimuth, and thus should not be construed as limiting the scope of protection of the present application; the orientation word "inner and outer" refers to inner and outer relative to the contour of the respective component itself.

The preferred embodiments of the present utility model will be described in detail below with reference to the accompanying drawings so that the advantages and features of the present utility model can be more easily understood by those skilled in the art, thereby making clear and defining the scope of the present utility model.

In an embodiment of the present application, referring to fig. 1 and 2, the present embodiment discloses a novel welding structure of a composite current collector, including a composite current collector layer 1 and a tab 2,

the composite current collecting layers 1 are provided with a plurality of layers, each composite current collecting layer 1 is connected with one conductive foil piece 3, and adjacent conductive foil pieces 3 are connected with each other and are electrically connected with the electrode lugs 2;

each composite current collector layer 1 includes a first metal layer 101, a second metal layer 102, and an insulating layer 103 which are stacked; an insulating layer 103 is provided between the first metal layer 101 and the second metal layer 102; for limiting the electrical connection of the first metal layer 101 and the second metal layer 102, the thickness of the first metal layer 101 and the second metal layer 102 is 30-70 nm.

A support 5 is arranged between the conductive foil 3 and the composite current collector layer 1 for supporting the conductive foil 3. Wherein the support 5 is made of an insulating material, such as: hard materials such as ceramics and carbon fibers.

The conductive foil member 3 includes an upper connection portion 301 connected to the first metal layer 101, a lower connection portion 303 connected to the second metal layer 102, and a bent portion 302 connecting the upper connection portion 301 and the lower connection portion 303.

In the embodiment, in the structure formed by welding the composite current collecting layer 1 and the tab 2 through the conductive foil, a supporting piece 5 is added, and the supporting piece 5 is arranged between the conductive foil 3 and the composite current collecting layer 1, namely, the inner side of the conductive foil 3, because both ends of the conductive foil 3, which are vertically connected with the composite current collecting layer 1, need to be welded, the conductive foil 3 and the conductive foil 3 need to be welded, and the body of the conductive foil 3 is a foil, and is easy to deform, and the supporting piece 5 is internally provided with the supporting parts which can realize the supporting of the upper connecting part 301, the lower connecting part 303 and the bending part 302 of the conductive foil 3; when the two ends of the conductive foil 3 are welded, due to the influence of factors such as temperature and air flow, both the upper connecting part 301 above the supporting piece 5 and the lower connecting part 303 below the supporting piece 5 are influenced, and the existence of the supporting piece 5 can reduce the traction tension applied to the foil at the two parts, so that the shrinkage deformation of the foil during welding is reduced, and the supporting piece 5 supports the bending part 302, so that the supporting piece plays a role in expanding when the conductive foil 3 is bent, and the problem of easily deforming the body of the conductive foil 3 is solved.

In an embodiment of the present application, referring to fig. 2, a supporting member 5 is disposed on one side of a composite current collecting layer 1 connected to a conductive foil member 3, the conductive foil member 3 is wrapped around the supporting member 5, two ends of the conductive foil member 3 connected to the composite current collecting layer 1 from top to bottom are respectively fixedly connected to a first metal layer 101 and a second metal layer 102, and the composite current collecting layer 1, the supporting member 5 and the conductive foil member 3 together form a composite welding unit 4. As shown in fig. 2, the section of the conductive foil 3 is U-shaped, two ends of the conductive foil 3 clamp one end of the composite current collector layer 1 and are welded and fixed, the conductive foil 3 wraps the supporting piece 5 for supporting the body inside the conductive foil, each point position where the inner part contacts can play a supporting role, the disadvantage that the foil is easy to deform is balanced, the deformation of the body caused by bending up and down can be prevented, and the deformation of the foil can be reduced during welding.

In this embodiment, the two ends of the conductive foil 3 are welded and fixed with the upper and lower surfaces of the composite current collector layer 1 respectively, that is, a single composite current collector layer 1 is welded with the conductive foil 3 to form a composite welding unit 4, and then each composite welding unit 4 is stacked up and down together and welded with the tab 2, so that the welding efficiency can be improved.

In an embodiment of the present application, referring to fig. 2, the supporting member 5 is in a plate-shaped structure, the longitudinal length of the supporting member is not less than the longitudinal length of the composite current collecting layer 1, the transverse length of the supporting member is greater than half of the transverse folded length of the conductive foil member 3, and the thickness of the supporting member 5 is equal to the thickness of the composite current collecting layer 1 and the supporting member and the composite current collecting layer are arranged in an up-down flush manner.

In this embodiment, the longitudinal direction of the support 5 and the longitudinal direction of the composite current collector layer 1 each refer to: perpendicular to the cross-section shown in fig. 2. The lateral direction of the support 5 and the lateral direction of the conductive foil 3 both refer to: the cross section shown in fig. 2 is in the horizontal direction.

When the conductive foil 3 is connected with the composite current collecting layer 1, the longitudinal direction of the conductive foil 3 covers the welding end of the composite current collecting layer 1, and the longitudinal length of the supporting piece 5 is not smaller than the longitudinal length of the composite current collecting layer 1, so that the supporting piece 5 can be ensured to completely cover the supporting range required by the longitudinal direction of the conductive foil 3.

The transverse length of the supporting piece 5 is larger than half of the transverse folded length of the conductive foil piece 3, and the transverse supporting coverage rate of the supporting piece 5 on the conductive foil piece 3 exceeds 50% in the state that the conductive foil piece 3 is welded with the composite current collector layer 1, so that the supporting stability can be better ensured.

The thickness of the supporting piece 5 is equal to that of the composite current collecting layer 1, so that the upper end face and the lower end face of the supporting piece 5 are respectively arranged in the same plane with the upper end face and the lower end face of the composite current collecting layer 1, the two ends of the conductive foil piece 3 are fixedly connected with the composite current collecting layer 1, the supporting piece 5 can keep stable up and down positions, the upper connecting portion 301 and the lower connecting portion 303 of the conductive foil piece 3 are relatively parallel to the composite current collecting layer 1, and the supporting piece 5 has better and more stable supporting effect.

In an embodiment of the present application, referring to fig. 2, a cross section of an end of the supporting member 5 abutting against the bending portion of the conductive foil member 3 is circular arc.

In this embodiment, since the upper connection portion 301 and the lower connection portion 303 of the conductive foil 3 are respectively connected to the upper end surface and the lower end surface of the composite current collector layer 1, the middle portion of the conductive foil 3 needs to be bent to form the bending portion 302; the position of the support piece 5 for supporting the bending part 302 is set to be in circular arc shape, so that the support piece can be better contacted with the inner side surface of the bending part 302, compared with other shapes such as square shapes, the circular arc-shaped support surface is more uniform in stress of each point, and better supporting effect can be achieved.

In an embodiment of the present application, a glue layer 6 is provided between the support 5 and the composite collector layer 1, see fig. 3.

In this embodiment, a relatively stable connection is formed between the support member 5 and the composite current collector layer 1 by applying the colloid, so that the support member 5 is prevented from being stressed to cause position deviation when the conductive foil member 3 is wrapped and welded by the composite current collector layer 1, and the support effect of the support member 5 is ensured.

In an embodiment of the present application, referring to fig. 1, the composite welding units 4 are connected up and down through conductive foil pieces 3, and adjacent conductive foil pieces 3 are electrically connected through welding upper and lower end surfaces of each other, where one conductive foil piece 3 is connected to the tab 2.

In this embodiment, the composite current collector layer 1 and the conductive foil pieces 3 are made into independent composite welding units 4, then each composite welding unit 4 is stacked up and down and then welded through the conductive foil pieces 3, and finally one of the conductive foil pieces 3 is welded with the tab 2, so that electrical connection between the upper and lower composite current collector layers 1 is realized, welding efficiency is improved, and welding operation is more convenient.

In an embodiment of the present application, not shown in the drawings, the conductive foil member 3 is an aluminum foil or a copper foil.

In this embodiment, the conductive foil member 3 may be an aluminum foil or a copper foil, both of which are suitable for welding the composite current collector layer 1; the preferred copper foil of this embodiment, the conductivity is good, and ductility is good, can with the better laminating of support piece 5 for support piece 5 plays better supporting role to the foil material.

According to the welding structure of the composite current collector, the supporting piece for supporting the conductive foil piece is arranged in the structure formed by welding the composite current collector layer and the electrode lugs through the conductive foil, and the traction tension born by the foil can be reduced during welding, so that the shrinkage deformation of the foil is reduced; the single composite current collecting layer and the conductive foil piece are welded into the composite welding unit, and each composite welding unit is stacked up and down and then welded with the electrode lug, so that the welding efficiency can be improved; the supporting piece is closely attached to the conductive foil piece, all points in contact are uniformly stressed, the supporting effect is good, and the welding deformation of the conductive foil piece is reduced.

The above embodiments are only for illustrating the technical concept and features of the present utility model, and are intended to enable those skilled in the art to understand the content of the present utility model and to implement the same, but are not intended to limit the scope of the present utility model, and all equivalent changes or modifications made according to the spirit of the present utility model should be included in the scope of the present utility model.

Claims (8)

1. The utility model provides a novel welded structure of compound current collector, includes compound current collector layer (1) and utmost point ear (2), its characterized in that:

the composite current collecting layers (1) are provided with multiple layers, each composite current collecting layer (1) is connected with one conductive foil piece (3), and adjacent conductive foil pieces (3) are connected with each other and are electrically connected with the electrode lugs (2);

each composite current collecting layer (1) comprises a first metal layer (101), a second metal layer (102) and an insulating layer (103) which are arranged in a laminated manner; the insulating layer (103) is arranged between the first metal layer (101) and the second metal layer (102);

a supporting piece (5) is arranged between the conductive foil piece (3) and the composite current collecting layer (1) and is used for supporting the conductive foil piece (3).

2. The welded structure according to claim 1, wherein: the support piece (5) is arranged on one side of the composite current collecting layer (1) connected with the conductive foil piece (3), the conductive foil piece (3) is wrapped outside the support piece (5), the conductive foil piece (3) is fixedly connected with the first metal layer (101) and the second metal layer (102) respectively at the two ends of the composite current collecting layer (1) which are vertically connected, and the composite current collecting layer (1), the support piece (5) and the conductive foil piece (3) jointly form a composite welding unit (4).

3. The welded structure according to claim 2, characterized in that: the supporting piece (5) is of a plate-shaped structure, the longitudinal length of the supporting piece is not smaller than that of the composite current collecting layer (1), the transverse length of the supporting piece is larger than half of the transverse folding length of the conductive foil piece (3), and the thickness of the supporting piece (5) is equal to that of the composite current collecting layer (1) and is flush with the composite current collecting layer.

4. A welded structure according to claim 3, characterized in that: the cross section of one end of the supporting piece (5) which is abutted against the bending part of the conductive foil piece (3) is arc-shaped.

5. The welded structure according to claim 4, wherein: an adhesive layer (6) is arranged between the supporting piece (5) and the composite current collecting layer (1).

6. The welded structure according to claim 5, wherein: the composite welding units (4) are connected up and down through conductive foil pieces (3), adjacent conductive foil pieces (3) are electrically connected through welding of upper end surfaces and lower end surfaces of the conductive foil pieces, and one conductive foil piece (3) is connected with the electrode lug (2).

7. The welded structure according to claim 6, wherein: the conductive foil piece (3) is an aluminum foil or a copper foil.

8. The welded structure according to claim 1, wherein: the material of the supporting piece (5) is ceramic or carbon fiber.