CN221486758U

CN221486758U - Pole piece, battery core structure and battery

Info

Publication number: CN221486758U
Application number: CN202323033970.5U
Authority: CN
Inventors: 臧世伟
Original assignee: Shenzhen Jinmei New Material Technology Co ltd
Current assignee: Shenzhen Jinmei New Material Technology Co ltd
Priority date: 2023-11-09
Filing date: 2023-11-09
Publication date: 2024-08-06
Anticipated expiration: 2033-11-09

Abstract

The application discloses a pole piece, a battery core structure and a battery, wherein the pole piece comprises a current collector and a pole lug, the current collector comprises a supporting layer, a conductive connecting area and an insulating connecting area are arranged on the supporting layer, and a conductive layer is arranged in the conductive connecting area; the electrode lug comprises a conductive connecting part and an insulating connecting part, and the insulating connecting part and the conductive connecting part are arranged in a lamination manner; at least part of the conductive connecting part is positioned in the conductive connecting area and welded with the conductive layer, and at least part of the insulating connecting part is positioned in the insulating connecting area and connected with the supporting layer. The application solves the problem of lower connection strength caused by the fact that the lugs of the battery and the current collector are connected only by means of metal welding in the prior art.

Description

Pole piece, battery core structure and battery

Technical Field

The application relates to the technical field of battery production and manufacturing, in particular to a pole piece, an electric core structure and a battery.

Background

The ion battery has the advantages of high energy density, excellent power performance, long cycle life and the like, and is widely applied to the field of new energy.

In the process of manufacturing the ion battery, the current collector is used as an important part, and when the current collector is used in the battery, the electrode lugs are welded on the current collector, and the current collector is used for collecting current so as to output the current better.

The existing tab is welded on the current collector only through a metal welding mode, so that the connection area between the current collector and the tab is small, the connection strength is low, the tab is easy to separate from the current collector, and the current transmission efficiency is reduced.

Disclosure of utility model

The application mainly aims to provide a pole piece, a battery core structure and a battery, which are used for solving the problem of lower connection strength caused by the fact that the pole lugs of the battery and a current collector are connected only by means of metal welding in the prior art.

According to one aspect of the application, there is provided a pole piece comprising a current collector and a pole lug, the current collector comprising a support layer, the support layer being provided with a conductive connection region and an insulating connection region, the conductive connection region being provided with a conductive layer therein; the electrode lug comprises a conductive connecting part and an insulating connecting part, and the insulating connecting part and the conductive connecting part are arranged in a lamination manner; at least part of the conductive connecting part is positioned in the conductive connecting area and welded with the conductive layer, and at least part of the insulating connecting part is positioned in the insulating connecting area and welded with the supporting layer.

Further, the conductive connection part comprises a metal connection belt body; at least part of the metal connecting band body is adhered to the surface of the conductive layer and welded with the conductive layer.

Further, the current collector further includes: the insulating layer is arranged in the insulating connection area and connected with the supporting layer, and the thickness of the insulating layer is smaller than that of the conducting layer; the insulating connecting part is welded with the insulating layer.

Further, the insulating connecting part comprises a connecting film; at least part of the connecting film is adhered to the surface of the insulating layer and welded with the insulating layer.

Further, the insulating connecting part comprises a connecting film, and the conductive connecting part comprises a metal connecting belt body; the connecting film is arranged on the surface of the metal connecting belt body, and the length of the metal connecting belt body is larger than that of the connecting film so as to form a first step structure between the metal connecting belt body and the connecting film.

Further, the current collector further comprises an insulating layer, the insulating layer is arranged in the insulating connection area, the conducting layer is located in the middle of the supporting layer, the insulating layer is located on the side of the conducting layer, a second step structure is arranged between the conducting layer and the insulating layer, and the second step structure is embedded with the first step structure.

Further, the connection film comprises a first connection film and a second connection film; the first connecting film and the second connecting film are respectively arranged at two sides of the metal connecting belt body, and the first connecting film or the second connecting film is connected with the supporting layer.

Further, the supporting layer is made of plastic, and the thickness of the supporting layer is 500nm to 8 mu m.

According to a second aspect of the application, there is provided a cell structure comprising a diaphragm and a pole piece, the diaphragm being connected to the pole piece, the pole piece being the pole piece described above.

According to a third aspect of the application, there is provided a battery comprising a cell membrane and a pole piece, the pole piece being connected to the cell membrane, the pole piece being the pole piece described above.

Compared with the prior art, the technical scheme of the application has at least the following technical effects:

In the actual processing process, the metal connecting strip body in the tab is only put on the conductive layer in the middle of the current collector, and then the connection between the current collector and the tab can be completed by welding; in addition, the application can also limit the material of the supporting layer, so that the connecting film is directly welded with the supporting layer by ultrasonic, or a layer of amorphous polymer is compounded or coated on the supporting layer to form the insulating layer, and then the connecting film is connected with the insulating layer, thereby the operation is simple and convenient, the insulativity of the pole piece is improved, and the connection between the pole lug and the current collector is more stable, so that the service life of the battery is prolonged.

Drawings

The accompanying drawings, which are included to provide a further understanding of the application and are incorporated in and constitute a part of this specification, illustrate embodiments of the application and together with the description serve to explain the application and do not constitute a limitation on the application. In the drawings:

FIG. 1 is a schematic diagram of an embodiment of a pole piece of the present disclosure;

fig. 2 is a schematic structural view of a current collector in a pole piece according to the present disclosure;

fig. 3 is a schematic structural view of a tab in a pole piece according to the present disclosure.

Wherein the above figures include the following reference numerals:

1. A current collector; 10. a support layer; 101. a conductive connection region; 102. an insulating connection region; 11. a conductive layer; 12. an insulating layer; 13. a second step structure; 2. a tab; 20. a conductive connection portion; 21. an insulating connection portion; 22. a first step structure; 201. a metal connecting band body; 210. connecting films; 2101. a first connection film; 2102. and a second connection film.

Detailed Description

It should be noted that, without conflict, the embodiments of the present application and features of the embodiments may be combined with each other. The application will be described in detail below with reference to the drawings in connection with embodiments.

It is noted that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of exemplary embodiments according to the present application. As used herein, the singular is also intended to include the plural unless the context clearly indicates otherwise, and furthermore, it is to be understood that the terms "comprises" and/or "comprising" when used in this specification are taken to specify the presence of stated features, steps, operations, devices, components, and/or combinations thereof.

The relative arrangement of the components and steps, numerical expressions and numerical values set forth in these embodiments do not limit the scope of the present application unless it is specifically stated otherwise. Meanwhile, it should be understood that the sizes of the respective parts shown in the drawings are not drawn in actual scale for convenience of description. Techniques, methods, and apparatus known to one of ordinary skill in the relevant art may not be discussed in detail, but should be considered part of the authorization specification where appropriate. In all examples shown and discussed herein, any specific values should be construed as merely illustrative, and not a limitation. Thus, other examples of the exemplary embodiments may have different values. It should be noted that: like reference numerals and letters denote like items in the following figures, and thus once an item is defined in one figure, no further discussion thereof is necessary in subsequent figures.

As described in the background art, in the existing current collector, only the conductive connection portion is usually welded between the current collector and the tab, the connection area between the current collector and the tab is small, and detachment between the tab and the current collector is easily caused in the use process, so that current transmission is affected. Therefore, in order to strengthen the joint strength between the tab and the current collector, the problem that the tab is easy to separate is solved, the welding point is increased, on the basis of the existing metal welding, the insulating joint area of the connecting film on the tab and the supporting layer in the current collector is welded, and in the welding process, the metal connecting belt body of the tab and the conductive layer lamination of the current collector are arranged, the connecting film of the tab and the insulating joint area lamination of the supporting body are arranged, the contact area between the tab and the current collector is increased, after welding, the problem that gaps are generated between the tab and the current collector to cause the tab to easily separate is avoided, the service life of the pole piece is prolonged in the process of using the pole piece, and the transmission efficiency of the pole piece is optimized.

Referring to fig. 1 to 3, the application provides a pole piece, which comprises a current collector 1 and a pole lug 2, wherein the current collector 1 comprises a supporting layer 10, a conductive connecting area 101 and an insulating connecting area 102 are arranged on the supporting layer 10, and a conductive layer 11 is arranged in the conductive connecting area 101; the tab 2 comprises a conductive connecting part 20 and an insulating connecting part 21, the insulating connecting part 21 and the conductive connecting part 20 are arranged in a laminated mode, the conductive connecting part 20 extends towards the current collector 1 relative to the insulating connecting part 21, and a first step structure 22 is arranged between the conductive connecting part 20 and the insulating connecting part 21; at least part of the conductive connection 20 is located in the conductive connection region 101 and soldered to the conductive layer 11, and at least part of the insulating connection 21 is located in the insulating connection region 102 and soldered to the supporting layer 10.

According to the pole piece provided by the application, the pole piece comprises a current collector 1 and a pole lug 2, wherein the current collector 1 comprises a supporting layer 10, a conductive connecting area 101 and an insulating connecting area 102 are arranged on the supporting layer 10, a conductive layer 11 is arranged in the conductive connecting area 101, the number of the insulating connecting areas 102 is two, the two insulating connecting areas 102 are respectively positioned at two sides of the conductive connecting area 101, the pole lug 2 comprises a conductive connecting part 20 and an insulating connecting part 21, the insulating connecting part 21 and the conductive connecting part 20 are arranged in a laminated mode so as to form a first step structure between the conductive connecting part 20 and the insulating connecting part 21, at least part of the conductive connecting part 20 is positioned in the conductive connecting area 101 and connected with the conductive layer 11, and at least part of the insulating connecting part 21 is positioned in the insulating connecting area 102 and connected with the supporting layer 10. In this way, two connection areas are arranged between the current collector 1 and the current collector 2, after the conductive connection part 20 is welded with the conductive layer 11, in order to strengthen the connection strength, the insulation connection part 21 is welded with the insulation connection area 102 on the support layer 10, and a double welding mode is adopted, so that the connection between the current collector 1 and the current collector 2 is more stable, the welding area between the current collector 1 and the current collector 2 is increased, and the separation between the current collector 1 and the current collector 2 is avoided.

As shown in fig. 2, the conductive connection part 20 includes a metal connection band 201; at least part of the metal connecting band 201 is attached to the surface of the conductive layer 11 and welded to the conductive layer 11, so that the problem of low connection strength after point contact welding between the conductive layer 11 and the metal connecting band 201 is avoided, and in the welding process, both the metal connecting band 201 and the conductive layer 11 can be welded in the circumferential direction of the metal connecting band 201 due to the attachment between the metal connecting band 201 and the conductive layer 11.

In the first embodiment provided by the application, the supporting layer 10 is directly welded to the insulating connecting portion 21 by ultrasonic, the conductive layer 11 is made of copper, aluminum, copper alloy or aluminum alloy, at least part of the metal connecting strip 201 is stacked on the surface of the conductive layer 11 in the process of connecting the current collector 1 with the tab 2, and the insulating connecting portion 21 is stacked in the insulating connecting region 102, the supporting layer 10 is made of amorphous polymer, such as ABS plastic, PC (polycarbonate), PS (polystyrene), PVC (polyvinyl chloride) or PMMA (polymethyl methacrylate), and the molecular arrangement of the materials is disordered, so that the materials are obviously softened and melted gradually to a flowing temperature, ultrasonic vibration can be effectively transmitted, and good welding is realized within a certain pressure/amplitude range, even if the supporting layer 10 and the insulating connecting portion 21 are combined into a whole after ultrasonic welding, so that stable connection of the supporting layer 10 and the insulating connecting portion 21 is ensured.

In this embodiment, the insulating connecting portion 21 includes a connecting film 210, at least a portion of the connecting film 210 is attached to the surface of the insulating connecting region 102 of the supporting layer 10, so as to increase the contact area between the connecting film 210 and the supporting layer 10, and the connecting film 210 is made of at least one material selected from ABS plastic, PC (polycarbonate), PS (polystyrene), PVC (polyvinylchloride) and PMMA (polymethyl methacrylate), so that the connection between the connecting film 210 and the supporting layer 10 is more firm after ultrasonic welding.

In a second embodiment provided by the present application, current collector 1 further comprises: an insulating layer 12 disposed in the insulating connection region 102 and connected to the supporting layer 10, the insulating layer 12 and the conductive layer 11 having a second step structure 13 fitted with the first step structure 22 therebetween; namely, the conductive layer 11 is positioned in the middle of the supporting layer 10, the insulating layer 12 is positioned at the side of the conductive layer 11, and the thickness of the conductive layer 11 is larger than that of the insulating layer 12 so as to form a second step structure; the insulating connecting portion 21 is welded to the insulating layer 12. By the mutual fitting between the first step structure 22 and the second step structure 13, after the current collector 1 and the tab 2 are connected, a gap is prevented from being generated between the current collector 1 and the tab 2, resulting in easy detachment between the tab 2 and the current collector 1. In this embodiment, the material of the supporting layer 10 is at least one of PP (polypropylene) and PET (polyethylene terephthalate), then the conductive connection region 101 and the insulating connection region 102 are divided on the supporting layer 10, the plating is performed in the conductive connection region 101 to form the conductive layer 11, the insulating layer 12 is disposed in the insulating connection region 102 of the supporting layer 10, the insulating layer 12 is at least one of amorphous polymers such as ABS plastic, PC (polycarbonate), PS (polystyrene), PVC (polyvinyl chloride) and PMMA (polymethyl methacrylate), and then the insulating layer 12 is ultrasonically welded with the insulating connection portion 21.

Specifically, the insulating connecting portion 21 includes a connecting film 210; at least a portion of the connection film 210 is adhered to the surface of the insulating layer 12 and welded to the insulating layer 12. The material of the connection film 210 is amorphous polymer, such as ABS plastic, PC (polycarbonate), PS (polystyrene), PVC (polyvinyl chloride) or PMMA (polymethyl methacrylate), so that the connection between the connection film 210 and the insulating layer 12 can be more firmly connected by means of ultrasonic welding.

In the actual welding process, the step end surface of the first step structure and the step end surface of the second step structure are mutually attached, the contact part of the conductive layer 11 and the metal connecting strip 201 is welded by metal, and the insulating layer 12 and the connecting film 210 are welded by ultrasonic.

In the tab 2 structure provided by the present application, as shown in fig. 3, the insulating connection part 21 includes a connection film 210, and the conductive connection part 20 includes a metal connection strip 201; the connection film 210 is disposed on the surface of the metal connection tape 201, and the length of the metal connection tape 201 is greater than that of the connection film 210 to form a first step structure between the metal connection tape 201 and the connection film 210.

Wherein the connection film 210 includes a first connection film 2101 and a second connection film 2102; the first connection film 2101 and the second connection film 2102 are respectively arranged at two sides of the metal connection belt body 201, and the first connection film 2101 or the second connection film 2102 is connected with the support layer 10. In use, the first and second attachment tabs 2101, 2102 are insulated portions of tab 2.

The supporting layer 10 is made of plastic, specifically, the supporting layer 10 is at least one of ABS plastic, PC (polycarbonate), PS (polystyrene), PVC (polyvinyl chloride), PMMA (polymethyl methacrylate), PP (polypropylene) and PET (polyethylene terephthalate), and as can be seen from the above embodiment, the specific material of the supporting layer 10 can be set according to different requirements; further, the thickness of the support layer 10 is 500nm to 8 μm. Too small a thickness of the supporting layer 10 can lead to a reduction in structural strength of the supporting layer 10, the supporting layer 10 is easy to break in the subsequent processing process, and too large a thickness of the supporting layer 10 can easily lead to a large space occupied by the whole structure of the pole piece.

In the present application, the current collector 1 further includes a base layer body, a transition layer body and a thickening layer body, the base layer body is disposed on the surface of the supporting layer 10, the base layer body is made of at least one of alumina, silicon nitride, silicon carbide, copper alloy, aluminum alloy and polyethylene glycol, the transition layer body is disposed on a side of the base layer body far away from the supporting layer 10, the base layer body is used for connecting the supporting layer 10 and the transition layer body, the thickening layer body is disposed on a side of the transition layer body far away from the base layer body, and the conductive layer 11 is disposed on a side of the thickening layer body far away from the transition layer body. Wherein the material of the transition layer body and the thickening layer body is at least one of copper, aluminum, copper alloy and aluminum alloy.

Specifically, when the thickness of the support layer 10 is 3 μm to 8 μm, the support layer 10 at this thickness may be prevented from being broken when coating in a vacuum coating apparatus or an electroplating apparatus, because the support layer 10 of the current collector 1 needs to be unfolded and leveled at the time of coating, and thus a force may be applied to the support layer 10, and if the thickness is too thin, the support layer 10 may be pulled apart.

When the thickness of the supporting layer 10 is 500nm to 2um, the thickness can improve the physical properties such as tensile strength of the current collector and the like, and can well play a role in converging current. Specifically, for example, when the total thickness of the conductive layer 11 is set to 500nm, the plating may be performed a plurality of times, for example, 100nm may be first plated, 100nm may be second-time plated, and 300nm may be third-time plated, the more times the conductive layer 11 on the surface of the support layer 10 is plated, the more uniform the conductive layer 11 is, because the more times the energy and the metal material each time the conductive layer 11 needs to be formed on the support layer 10 are less, the more uniform the heating of the metal material is, and thus the more uniform the conductive layer 11 is formed on the support layer 10. In order to reduce the cost, the number of coating times is generally not more than 3.

In the process of arranging the substrate layer body, the transition layer body and the thickening layer body, a coating mode is adopted for the substrate layer body, a magnetron sputtering coating mode is adopted for the substrate layer body, an evaporation coating mode is adopted for the transition layer body, and an electroplating coating mode is adopted for the thickening layer body. The reason that the base layer body adopts the magnetron sputtering coating is that the magnetron sputtering coating generates large energy, so that the metal can be better combined with the supporting layer 10, the combination is firmer, and the formed coating is denser. The transition layer adopts the evaporation plating because the evaporation plating cost is lower than that of the magnetron, and on the premise of the magnetron sputtering bottoming, the metal transition layer formed by the magnetron sputtering increases the heat resistance of the supporting layer, so the supporting layer 10 cannot be sintered into holes by adopting the evaporation plating in the transition coating stage. The thickening layer body is mainly used for increasing the overall thickness of the current collector 1, because the water electroplating mode is lower than the evaporation cost, and the conducting layer formed at one time is thicker, so that the coating efficiency can be improved.

In the pole piece of the present application, the material of the supporting layer 10 and the connection film 210 are defined, and the insulating connection region 102 of the supporting layer 10 and the connection film 210 of the tab are connected by ultrasonic welding, that is, high-frequency vibration waves are transmitted to the surfaces of the supporting layer 10 and the connection film, so that the surfaces of two objects are rubbed with each other under the condition of pressurization, thereby fusing the molecular layers.

The application also provides an electric core structure which comprises a diaphragm and a pole piece, wherein the diaphragm is connected with the pole piece, and the pole piece is the pole piece of the embodiment. In the specific use process, the pole piece is connected with the diaphragm, and the current generated in the electrolyte is collected through the pole piece and then output to target equipment. By adopting the pole piece in the embodiment, the structural strength is improved, and the service life of the battery cell structure is prolonged.

The application also provides a battery, which comprises the battery cell diaphragm and a pole piece, wherein the pole piece is connected with the battery cell diaphragm, and the pole piece is the pole piece of the embodiment. In the application process, the positive electrode tab of the battery is made of an aluminum material, and the negative electrode tab is made of nickel or copper nickel plating material. In other words, in the above embodiment, the metal connection band in the positive electrode tab is made of an aluminum material, and the metal connection band in the negative electrode tab is made of a nickel or copper-plated nickel material.

From the above description, it can be seen that the above-described embodiments of the present application achieve the following technical effects:

Compared with the prior art, the current collector and the tab are welded only through metal parts, the connection mode is single, the tab is easy to separate from the current collector, and the connection strength is low.

Spatially relative terms, such as "above … …," "above … …," "upper surface on … …," "above," and the like, may be used herein for ease of description to describe one device or feature's spatial location relative to another device or feature as illustrated in the figures. It will be understood that the spatially relative terms are intended to encompass different orientations in use or operation in addition to the orientation depicted in the figures. For example, if the device in the figures is turned over, elements described as "above" or "over" other devices or structures would then be oriented "below" or "beneath" the other devices or structures. Thus, the exemplary term "above … …" may include both orientations "above … …" and "below … …". The device may also be positioned in other different ways (rotated 90 degrees or at other orientations) and the spatially relative descriptors used herein interpreted accordingly.

In addition, the terms "first", "second", etc. are used to define the components, and are only for convenience of distinguishing the corresponding components, and the terms have no special meaning unless otherwise stated, and therefore should not be construed as limiting the scope of the present application.

The above is only a preferred embodiment of the present application, and is not intended to limit the present application, but various modifications and variations can be made to the present application by those skilled in the art. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application should be included in the protection scope of the present application.

Claims

1. A pole piece comprises a current collector (1) and a pole lug (2), and is characterized in that,

The current collector (1) comprises a supporting layer (10), wherein a conductive connecting area (101) and an insulating connecting area (102) are arranged on the supporting layer (10), and a conductive layer (11) is arranged in the conductive connecting area (101);

The electrode lug (2) comprises a conductive connecting part (20) and an insulating connecting part (21), and the insulating connecting part (21) and the conductive connecting part (20) are arranged in a laminated mode;

At least part of the conductive connection (20) is located in the conductive connection region (101) and welded with the conductive layer (11), and at least part of the insulating connection (21) is located in the insulating connection region (102) and welded with the support layer (10).

2. The pole piece of claim 1, wherein the conductive connection (20) comprises a metal connection strip (201);

At least part of the metal connecting strip body (201) is adhered to the surface of the conductive layer (11) and welded with the conductive layer (11).

3. Pole piece according to claim 1, characterized in that the current collector (1) further comprises:

An insulating layer (12) disposed within the insulating connection region (102) and connected to the support layer (10), the insulating layer (12) having a thickness less than the thickness of the conductive layer (11);

The insulating connection (21) is welded to the insulating layer (12).

4. A pole piece according to claim 3, characterized in that the insulating connection (21) comprises a connection film (210);

At least part of the connection film (210) is adhered to the surface of the insulating layer (12) and welded to the insulating layer (12).

5. The pole piece of claim 1, wherein the insulating connection (21) comprises a connection film (210), and the conductive connection (20) comprises a metal connection strip (201);

the connecting film (210) is arranged on the surface of the metal connecting belt body (201), and the length of the metal connecting belt body (201) is larger than that of the connecting film (210) so as to form a first step structure between the metal connecting belt body (201) and the connecting film (210).

6. The pole piece according to claim 5, characterized in that the current collector (1) further comprises an insulating layer (12), the insulating layer (12) is arranged in the insulating connection area (102), the conductive layer (11) is located in the middle of the supporting layer (10), the insulating layer (12) is located at the side of the conductive layer (11), and a second step structure is arranged between the conductive layer (11) and the insulating layer (12), and the second step structure is mutually embedded with the first step structure.

7. The pole piece of claim 5, wherein the connection film (210) comprises a first connection film (2101) and a second connection film (2102);

The first connecting film (2101) and the second connecting film (2102) are respectively arranged on two sides of the metal connecting belt body (201), and the first connecting film (2101) or the second connecting film (2102) is connected with the supporting layer (10).

8. Pole piece according to claim 1, characterized in that the supporting layer (10) is a plastic layer, the supporting layer (10) having a thickness of 500nm to 8 μm.

9. A cell structure comprising a membrane and a pole piece, the membrane being connected to the pole piece, characterized in that the pole piece is a pole piece according to any one of claims 1 to 8.

10. A battery comprising a cell membrane and a pole piece connected to the cell membrane, characterized in that the pole piece is a pole piece according to any one of claims 1 to 8.