CN217822876U - Current collector, pole piece, electrode assembly, single battery and battery - Google Patents

Abstract

The application relates to a mass flow body, pole piece, electrode subassembly, battery monomer and battery, the mass flow body includes: an insulating layer; the first current collecting layer and the second current collecting layer are respectively arranged on two opposite sides of the insulating layer; and the conducting layer is arranged between the first current collecting layer and the insulating layer and/or between the second current collecting layer and the insulating layer. The single current collector, the pole piece, the electrode assembly, the single battery and the battery provided in the application can reduce the initial internal resistance of the single battery, so that the single battery and the battery have better working reliability.

Description

Current collector, pole piece, electrode assembly, single battery and battery

Technical Field

The application relates to the technical field of batteries, in particular to a current collector, a pole piece, an electrode assembly, a battery monomer and a battery.

Background

Energy conservation and emission reduction are the key points of sustainable development of the automobile industry, and electric vehicles become important components of the sustainable development of the automobile industry due to the advantages of energy conservation and environmental protection. For electric vehicles, battery technology is an important factor in its development.

The battery is formed by combining a plurality of battery monomers, and after the traditional battery monomers are manufactured, the initial internal resistance of the traditional battery monomers is higher, so that the working reliability of the battery monomers and the battery is reduced.

SUMMERY OF THE UTILITY MODEL

In view of the above problems, the present application provides a current collector, a pole piece, an electrode assembly, a single battery and a battery, which can reduce the initial internal resistance of the single battery, so that the single battery and the battery have better operational reliability.

In a first aspect, the present application provides a current collector comprising:

an insulating layer;

the first current collecting layer and the second current collecting layer are respectively arranged on two opposite sides of the insulating layer; and

and the conducting layer is arranged between the first current collecting layer and the insulating layer and/or between the second current collecting layer and the insulating layer.

The conducting layer is arranged between the first current collecting layer and the insulating layer and/or between the second current collecting layer and the insulating layer, so that on one hand, the conducting layer has the flow guiding capacity, and the arrangement of the conducting layer can increase the flow area so as to avoid the increase of the initial internal resistance of the single battery; on the other hand, the conducting layer can make up the extended microcracks of the first current collecting layer and/or the second current collecting layer, and even if the extended microcracks are continuously corroded by the electrolyte, the conducting layer can still provide a complete conducting network, so that the single battery and the battery have better working reliability.

In some embodiments, a conductive layer is stacked between the first current collecting layer and the insulating layer, and between the second current collecting layer and the insulating layer.

Through all range upon range of being provided with the conducting layer between first current collecting layer and insulating layer to and between second current collecting layer and the insulating layer, then no matter produce the micro crack on first current collecting layer or the second current collecting layer, all can guarantee that battery monomer has less initial resistance and complete conductive network to can realize the purpose of optimizing the operational reliability of battery monomer and battery.

In some embodiments, the conductive layer is a conductive polymer layer.

The conductive polymer has good conductive performance and heat resistance, so that the conductive polymer layer formed by the conductive polymer also has better flow conductivity, and the conductive polymer is less prone to thermal runaway in the working process. In addition, the manufacturing cost of the conductive polymer is lower than that of metal, so that the manufacturing cost of the battery cell can be effectively reduced.

In some embodiments, the conductivity σ of the conductive layer satisfies the condition: 10 ² S/m≤σ≤10 ⁷ S/m。

The condition is satisfied by setting the conductivity σ of the conductive layer: 10 ² S/m≤σ≤10 ⁷ S/m, the conducting layer with the conductivity sigma has a good flow guiding effect, and therefore the working reliability of single batteries and batteries is improved.

In some embodiments, the conductivity σ of the conductive layer satisfies the condition: 10 ⁵ S/m≤σ≤10 ⁶ S/m。

The condition is satisfied by setting the conductivity σ of the conductive layer: 10 ⁵ S/m≤σ≤10 ⁶ S/m，The conductive layer with the conductivity sigma has excellent flow guiding effect, thereby being beneficial to improving the working reliability of the single battery and the battery. And the conducting layer with the conductivity sigma in the range is less difficult to manufacture, so that the manufacturing cost of the current collector can be reduced.

In some embodiments, the conductive layer is configured as a conductive composite layer compounded from a conductive polymer and a binder.

The conductive composite layer compounded with the binder has better bonding performance, and can improve the bonding force between the insulating layer and the first current collecting layer when the conductive composite layer is arranged between the insulating layer and the first current collecting layer; when the insulating layer is arranged between the insulating layer and the second current collecting layer, the binding force between the insulating layer and the second current collecting layer can be improved, so that the insulating layer is prevented from being separated from the first current collecting layer and/or the second current collecting layer, and the single battery and the battery have better use safety.

In some embodiments, in the conductive layer, the compounding ratio K of the binder to the conductive polymer satisfies the condition: k is more than 0 percent and less than or equal to 20 percent.

The condition is satisfied by setting the composite ratio K of the binder and the conductive polymer: k is more than 0% and less than or equal to 20%, so that the layer structures in the current collector can be well combined, and the current guide capacity is good.

In some embodiments, the compounding ratio K of the binder to the conductive polymer satisfies the condition: k is more than or equal to 1 percent and less than or equal to 2 percent.

Like this, when can ensure can be better combination between the inside layer structure of mass flow body, can also promote the water conservancy diversion effect of mass flow body.

In some embodiments, the thickness H of the conductive layer satisfies the condition: h is more than or equal to 0.1um and less than or equal to 10um.

The condition is satisfied by setting the thickness H of the conductive layer: h is more than or equal to 0.1um and less than or equal to 10um, so that the flow conductivity of the current collector can be improved, and the manufacturing cost of the current collector can be reduced.

In some embodiments, the thickness H of the conductive layer satisfies the condition: h is more than or equal to 0.2um and less than or equal to 1um.

In the embodiment, the conductive layer has a small thickness, low manufacturing cost and good conductivity.

In a second aspect, the present application provides a pole piece comprising the current collector of any of the embodiments described above.

In a third aspect, the present application provides an electrode assembly comprising the above-described pole piece.

In a fourth aspect, the present application provides a battery cell including the above-described electrode assembly.

In a fifth aspect, the present application provides a battery including the above battery cell.

The above description is only an overview of the technical solutions of the present application, and the present application may be implemented in accordance with the content of the description so as to make the technical means of the present application more clearly understood, and the detailed description of the present application will be given below in order to make the above and other objects, features, and advantages of the present application more clearly understood.

Drawings

Various other advantages and benefits will become apparent to those of ordinary skill in the art upon reading the following detailed description of the preferred embodiments. The drawings are only for purposes of illustrating the preferred embodiments and are not to be construed as limiting the application. Also, like reference numerals are used to refer to like parts throughout the drawings. In the drawings:

FIG. 1 is an exploded view of a battery according to some embodiments of the present application;

fig. 2 is an exploded view of a battery cell in some embodiments of the present application;

fig. 3 is a schematic structural view of a current collector in some embodiments of the present application.

Reference numerals:

1. a battery; 10. a box body; 11. a first portion; 12. a second portion; 20. a battery cell; 21. an end cap; 22. a housing; 23. an electrode assembly; 231. a current collector; 2311. an insulating layer; 2312. a first current collector layer; 2313. a second current collector layer; 2314. and a conductive layer.

Detailed Description

In order to make the aforementioned objects, features and advantages of the present application more comprehensible, embodiments accompanying the present application are described in detail below with reference to the accompanying drawings. In the following description, numerous specific details are set forth in order to provide a thorough understanding of the present application. This application is capable of embodiments in many different forms than those described herein and that modifications may be made by one skilled in the art without departing from the spirit and scope of the application and it is therefore not intended to be limited to the specific embodiments disclosed below.

In the description of the present application, it is to be understood that the terms "center," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," "counterclockwise," "axial," "radial," "circumferential," and the like are used in the orientations and positional relationships indicated in the drawings for convenience in describing the present application and for simplicity in description, and are not intended to indicate or imply that the referenced devices or elements must have a particular orientation, be constructed and operated in a particular orientation, and are therefore not to be considered limiting of the present application.

Furthermore, the terms "first", "second" and "first" are used for descriptive purposes only and are not to be construed as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one such feature. In the description of the present application, "plurality" means at least two, e.g., two, three, etc., unless specifically limited otherwise.

In this application, unless expressly stated or limited otherwise, the terms "mounted," "connected," "secured," and the like are to be construed broadly and can include, for example, fixed connections, removable connections, or integral parts; can be mechanically or electrically connected; they may be directly connected or indirectly connected through intervening media, or they may be connected internally or in any other suitable relationship, unless expressly stated otherwise. The specific meaning of the above terms in the present application can be understood by those of ordinary skill in the art as the case may be.

In this application, unless expressly stated or limited otherwise, the first feature "on" or "under" the second feature may be directly contacting the first and second features or indirectly contacting the first and second features through intervening media. Also, a first feature "on," "over," and "above" a second feature may be directly or diagonally above the second feature, or may simply indicate that the first feature is at a higher level than the second feature. A first feature "under," "beneath," and "under" a second feature may be directly under or obliquely under the second feature, or may simply mean that the first feature is at a lesser elevation than the second feature.

It will be understood that when an element is referred to as being "secured to" or "disposed on" another element, it can be directly on the other element or intervening elements may also be present. When an element is referred to as being "connected" to another element, it can be directly connected to the other element or intervening elements may also be present. As used herein, the terms "vertical," "horizontal," "upper," "lower," "left," "right," and the like are for purposes of illustration only and do not denote a single embodiment.

At present, the application of the battery is more and more extensive from the development of market situation. The battery is not only applied to energy storage power supply systems such as hydraulic power, firepower, wind power and solar power stations, but also widely applied to electric vehicles such as electric bicycles, electric motorcycles and electric automobiles, and a plurality of fields such as military equipment and aerospace. As the field of application of batteries is continuously expanded, the market demand thereof is also continuously expanded.

The present inventors have noted that during the charge and discharge cycle operation of the battery, the initial internal resistance of the battery cell in the battery is large, which directly affects the operational reliability of the battery, resulting in a decrease in the operational reliability of the battery. The inventors have carefully studied and found that the main cause of the initial internal resistance of the battery cell is the presence of micro-cracks on the first current collector layer and/or the second current collector layer on the current collector.

Specifically, an electrode assembly in a battery cell comprises a positive plate and a negative plate, wherein the positive plate and the negative plate respectively comprise a current collector, a first active material layer and a second active material layer. The traditional current collector comprises an insulating layer, a first current collecting layer and a second current collecting layer, wherein the first current collecting layer and the second current collecting layer are respectively arranged on two opposite sides of the insulating layer in a stacking mode, a first active material layer is arranged on one side, back to the insulating layer, of the first current collecting layer in a stacking mode, a second active material layer is arranged on one side, back to the insulating layer, of the second current collecting layer in a stacking mode, the first active material layer and the second active material layer can react with electrolyte and generate current, and the first current collecting layer and the second current collecting layer are used for collecting the current and outputting the current to the outside.

Generally, the first current collecting layer and the second current collecting layer are both metal layers, and if the thicknesses of the first current collecting layer and the second current collecting layer are larger, thermal runaway is easy to occur in the working process of the single battery. In order to prevent thermal runaway, in a conventional battery cell, both the first current collecting layer and the second current collecting layer are ultra-thin layers. In the process that the current collector, the first active material layer and the second active material layer are stacked and compacted to form the positive plate or the negative plate, micro cracks are easily generated on the ultrathin first current collecting layer and the ultrathin second current collecting layer, the flow area of the battery is reduced, and the initial resistance is increased.

Based on the above considerations, the applicant has studied and found that it is possible to provide an electrically conductive layer between the insulating layer and the first current collector, and/or between the insulating layer and the second current collector. The conducting layer has the flow guiding capacity, and the flow area of the current collector can be increased due to the arrangement of the conducting layer, so that even if micro cracks are generated in the compacting process of the first current collecting layer and/or the second current collecting layer, the increase of the initial internal resistance of the single battery can be avoided, and the single battery and the battery have better working reliability.

Referring to fig. 1, fig. 1 is an exploded view of a battery 1 according to some embodiments of the present disclosure. The battery 1 includes a case 10 and a battery cell 20, and the battery cell 20 is accommodated in the case 10. The case 10 is used to provide a receiving space for the battery cell 20, and the case 10 may have various structures. In some embodiments, the case 10 may include a first portion 11 and a second portion 12, the first portion 11 and the second portion 12 cover each other, and the first portion 11 and the second portion 12 together define a receiving space for receiving the battery cell 20. The second part 12 may be a hollow structure with one open end, the first part 11 may be a plate-shaped structure, and the first part 11 covers the open side of the second part 12, so that the first part 11 and the second part 12 jointly define a containing space; the first portion 11 and the second portion 12 may be both hollow structures with one side open, and the open side of the first portion 11 may cover the open side of the second portion 12. Of course, the case 10 formed by the first and second portions 11 and 12 may have various shapes, such as a cylinder, a rectangular parallelepiped, and the like.

In the battery 1, the number of the battery cells 20 may be plural, and the plural battery cells 20 may be connected in series or in parallel or in series-parallel, where in series-parallel refers to both series connection and parallel connection among the plural battery cells 20. The plurality of battery cells 20 can be directly connected in series or in parallel or in series-parallel, and the whole formed by the plurality of battery cells 20 is accommodated in the box body 10; of course, the battery 1 may also be formed by connecting a plurality of battery cells 20 in series, in parallel, or in series-parallel to form a battery 1 module, and then connecting a plurality of battery 1 modules in series, in parallel, or in series-parallel to form a whole, and accommodating the whole in the box 10. The battery 1 may further include other structures, for example, the battery 1 may further include a bus member for achieving electrical connection between the plurality of battery cells 20.

Wherein, each battery cell 20 may be a secondary battery 1 or a primary battery 1; but not limited thereto, the lithium-sulfur battery 1, the sodium-ion battery 1, or the magnesium-ion battery 1 may also be used. The battery cell 20 may be cylindrical, flat, rectangular parallelepiped, or other shapes.

Referring to fig. 2, fig. 2 is an exploded view of a battery cell 20 according to some embodiments of the present disclosure. The battery cell 20 refers to the smallest unit constituting the battery 1. As shown in fig. 2, the battery cell 20 includes an end cap 21, a case 22, an electrode assembly 23, and other functional components.

The end cap 21 refers to a member that covers an opening of the case 22 to isolate the internal environment of the battery cell 20 from the external environment. Without limitation, the shape of the end cap 21 may be adapted to the shape of the housing 22 to fit the housing 22. Alternatively, the end cap 21 may be made of a material (e.g., an aluminum alloy) having a certain hardness and strength, so that the end cap 21 is not easily deformed when being impacted, and the battery cell 20 may have a higher structural strength and improved safety. The end cap 21 may be provided with functional parts such as electrode terminals. The electrode terminals may be used to electrically connect with the electrode assembly 23 for outputting or inputting electric energy of the battery cell 20. In some embodiments, the end cap 21 may further include a pressure relief mechanism for relieving the internal pressure when the internal pressure or temperature of the battery cell 20 reaches a threshold value. The material of the end cap 21 may be various materials, such as copper, iron, aluminum, stainless steel, aluminum alloy, plastic, etc., and the embodiment of the present invention is not limited thereto. In some embodiments, insulation may also be provided on the inside of the end cap 21, which may be used to isolate the electrical connection components within the housing 22 from the end cap 21 to reduce the risk of short circuits. Illustratively, the insulator may be plastic, rubber, or the like.

The case 22 is an assembly for mating with the end cap 21 to form an internal environment of the battery cell 20, wherein the formed internal environment may be used to house the electrode assembly 23, electrolyte, and other components. The housing 22 and the end cap 21 may be separate components, and an opening may be formed in the housing 22, and the opening may be covered by the end cap 21 to form the internal environment of the battery cell 20. The end cap 21 and the housing 22 may be integrated, and specifically, the end cap 21 and the housing 22 may form a common connecting surface before other components are inserted into the housing, and when it is required to seal the inside of the housing 22, the end cap 21 covers the housing 22. The housing 22 may be a variety of shapes and sizes, such as rectangular parallelepiped, cylindrical, hexagonal prism, etc. Specifically, the shape of the case 22 may be determined according to the specific shape and size of the electrode assembly 23. The material of the housing 22 may be various materials, such as copper, iron, aluminum, stainless steel, aluminum alloy, plastic, etc., and the embodiment of the present invention is not limited thereto.

The electrode assembly 23 is a part in which electrochemical reactions occur in the battery cell 20. One or more electrode assemblies 23 may be contained within the case 22. The electrode assembly 23 is mainly formed by winding or stacking a positive electrode sheet and a negative electrode sheet, and a separator is generally disposed between the positive electrode sheet and the negative electrode sheet. Both the positive plate and the negative plate comprise a current collector 231, a first active material layer and a second active material layer, and the first active material layer and the second active material layer are arranged on two opposite sides of the current collector 231 at intervals. During the charging and discharging process of the battery 1, the positive electrode active material on the first active material layer and the second active material layer on the positive electrode sheet and the negative electrode active material on the first active material layer and the second active material layer on the negative electrode sheet react with the electrolyte to form current, and the current collectors 231 on the positive electrode sheet and the negative electrode sheet are used for collecting the current and conducting the current to the outside.

The active materials on the first active material layer and the second active material layer on the positive plate are the same positive active material, such as: graphite. The active materials on the first active material layer and the second active material layer on the negative electrode sheet are the same type of negative electrode active material, such as: and (3) lithium.

Referring to fig. 3, fig. 3 is a schematic structural diagram of a current collector 231 according to some embodiments of the present disclosure. The current collector 231 includes an insulating layer 2311, a first current collecting layer 2312, a second current collecting layer 2313 and a conductive layer 2314, wherein the first current collecting layer 2312 and the second current collecting layer 2313 are respectively disposed on two opposite sides of the insulating layer 2311, and the conductive layer 2314 is disposed between the first current collecting layer 2312 and the insulating layer 2311 and/or between the second current collecting layer 2313 and the insulating layer 2311.

Specifically, the first current collector layer 2312 and the second current collector layer 2313 are formed of the same material layer, for example, a copper layer, an aluminum layer, and the like. The thickness of the first current collecting layer 2312 and the second current collecting layer 2313 is in the range of 0.1um to 10um.

The insulating layer 2311 functions to support the first and second collecting layers 2312 and 2313, and the insulating layer 2311 enables insulation between the first and second collecting layers 2312 and 2313. For example, the insulating layer 2311 may be a PET (poly terephthalic acid plastic) layer. The thickness of the insulating layer 2311 is in a range of 1um to 20 um.

Conductive layer 2314 can be made using metal, polymer, or other materials. The conductive layer 2314 has a current-conducting capability, which can direct current flow and achieve current collection.

The first current collector layer 2312 and/or the second current collector layer 2313 in the conventional battery cell 20 are susceptible to microcracking during compaction. The flow area of the first current collecting layer 2312 or the second current collecting layer 2313 having the microcracks is decreased, resulting in an increase in the initial resistance of the battery cell 20. In addition, the electrolyte is also easily concentrated at the microcracks and corrodes the first current collecting layer 2312 or the second current collecting layer 2313, so that the cracks are proliferated to damage the conductive network, and the working reliability of the battery cell 20 is deteriorated.

In the present application, by disposing the conductive layer 2314 between the first current collecting layer 2312 and the insulating layer 2311 and/or between the second current collecting layer 2313 and the insulating layer 2311, on one hand, the conductive layer 2314 has a current-conducting capability, and the disposition of the conductive layer 2314 can increase the overcurrent area to avoid an increase in the initial internal resistance of the battery cell 20; on the other hand, the conductive layer 2314 can compensate for the extended microcracks of the first current collecting layer 2312 and/or the second current collecting layer 2313, and even if the extended microcracks are continuously corroded by the electrolyte, the conductive layer 2314 can still provide a complete conductive network, so that the single battery 20 and the battery 1 have better working reliability.

In some embodiments of the present application, a conductive layer 2314 is stacked between the first current collecting layer 2312 and the insulating layer 2311, and between the second current collecting layer 2313 and the insulating layer 2311.

That is, the conductive layer 2314 is at least two layers, at least one of which is stacked between the first current collecting layer 2312 and the insulating layer 2311, and at least another of which is stacked between the second current collecting layer 2313 and the insulating layer 2311.

By laminating the conductive layers 2314 between the first current collecting layer 2312 and the insulating layer 2311 and between the second current collecting layer 2313 and the insulating layer 2311, the battery cell 20 can be ensured to have smaller initial resistance and a complete conductive network no matter microcracks are generated on the first current collecting layer 2312 or the second current collecting layer 2313, and therefore the purpose of optimizing the working reliability of the battery cell 20 and the battery 1 can be achieved.

In some embodiments of the present application, conductive layer 2314 is a conductive polymer layer.

The conductive polymer layer refers to a layered structure formed by coating a conductive polymer. The conductive polymer may be, but not limited to, a polyaniline, a polypyrrole, a polythiophene, and other conjugated polymer materials.

The conductive polymer has good conductive performance and heat resistance, so that the conductive polymer layer formed by the conductive polymer also has better flow conductivity, and the conductive polymer is less prone to thermal runaway in the working process. In addition, the manufacturing cost of the conductive polymer is relatively low compared to that of metal, so that the manufacturing cost of the battery cell 20 can be effectively reduced.

In some embodiments of the present application, the conductivity σ of the conductive layer 2314 satisfies the condition: 10 ² S/m≤σ≤10 ⁷ S/m。

The higher the conductivity of the conductive layer 2314, the higher the current conductivity of the conductive layer 2314, and the smaller the initial resistance of the formed battery cell 20, and the higher the discharge capacity of the battery cell 20 per unit time. In this way, the operational reliability of the battery cell 20 and the battery 1 is also better.

The condition is satisfied by setting the conductivity σ of the conductive layer 2314: 10 ² S/m≤σ≤10 ⁷ S/m, the conductive layer 2314 having such conductivity σ has a better current guiding effect, thereby contributing to the improvement of the operational reliability of the battery cell 20 and the battery 1.

In some embodiments of the present application, the conductivity σ of the conductive layer 2314 satisfies the condition: 10 ⁵ S/m≤σ≤10 ⁶ S/m。

The condition is satisfied by setting the conductivity σ of the conductive layer 2314: 10 ⁵ S/m≤σ≤10 ⁶ S/m, the conductive layer 2314 having such conductivity σ has an excellent current guiding effect, thereby contributing to improvement of operational reliability of the battery cell 20 and the battery 1. And the conductive layer with the conductivity sigma in the range is less difficult to manufacture, so that the manufacturing cost of the current collector 231 can be reduced.

In some embodiments of the present application, the conductive layer 2314 is configured as a conductive composite layer compounded by a conductive polymer and a binder.

The conductive composite layer is formed by a layered structure formed by coating a material obtained by compounding a conductive polymer and a binder. Among them, the binder may be polyurethane, amino resin, polyimide, etc.

The conductive composite layer compounded with the binder has good bonding performance, and when the conductive composite layer is arranged between the insulating layer 2311 and the first current collecting layer 2312, the bonding force between the insulating layer 2311 and the first current collecting layer 2312 can be improved; when the current collector is arranged between the insulating layer 2311 and the second current collecting layer 2313, the binding force between the insulating layer 2311 and the second current collecting layer 2313 can be improved, so that the insulating layer 2311 is prevented from being separated from the first current collecting layer 2312 and/or the second current collecting layer 2313, and the single battery 20 and the battery 1 have better use safety.

In some embodiments of the present application, in the conductive layer 2314, a compounding ratio K of the binder to the conductive polymer satisfies a condition: k is more than 0 percent and less than or equal to 20 percent.

The larger the proportion of the binder is, the better the bonding force between the insulating layer 2311 and the first current collecting layer 2312 and/or the second current collecting layer 2313 is; the larger the proportion of the conductive polymer, the better the conductivity of the conductive layer 2314.

In order to ensure that the conductive layer 2314 can improve the bonding force between the insulating layer 2311 and the first current collecting layer 2312 and/or the second current collecting layer 2313 and improve the flow guiding effect of the current collector 231, the compounding ratio of the binder to the conductive polymer needs to be set within a proper range.

The condition is satisfied by setting the composite ratio K of the binder and the conductive polymer: k is more than 0% and less than or equal to 20%, so that the layer structures in the current collector 231 can be well combined, and the current-guiding capacity is good.

In some embodiments of the present application, the compounding ratio K of the binder to the conductive polymer satisfies the condition: k is more than or equal to 1 percent and less than or equal to 2 percent.

In this embodiment, the binder is present in a smaller proportion and the conductive polymer is present in a larger proportion.

Like this, can also promote the water conservancy diversion effect of mass flow body 231 when can ensure can be better combination between the inside layer structure of mass flow body 231.

In some embodiments of the present application, the thickness H of the conductive layer 2314 satisfies the condition: h is more than or equal to 0.1um and less than or equal to 10um.

The thinner the thickness H of the conductive layer 2314 is, the lower the manufacturing cost of the conductive layer 2314 is.

By setting the thickness H of the conductive layer 2314 to satisfy the condition: h is more than or equal to 0.1um and less than or equal to 10um, so that the flow conductivity of the current collector 231 can be improved, and the manufacturing cost of the current collector 231 can be reduced.

In some embodiments of the present application, the thickness H of the conductive layer 2314 satisfies the condition: h is more than or equal to 0.2um and less than or equal to 1um.

In this embodiment, the conductive layer 2314 has a small thickness, low manufacturing cost, and good current-conducting capability.

Thus, while the manufacturing costs of the battery cell 20 and the battery 1 can be reduced, the conductive layer 2314 can be ensured to have good current-conducting capacity.

In a second aspect, the present application further provides a pole piece, including the current collector 231 according to any of the above aspects.

In a third aspect, the present application further provides an electrode assembly 23, including the pole piece in the above scheme.

In a fourth aspect, the present application also provides a battery cell 20 including the electrode assembly 23 of the above aspect.

In a fifth aspect, the present application further provides a battery 1 including the battery cell 20 according to the above aspect.

According to some embodiments of the present disclosure, referring to fig. 3, the present disclosure provides a current collector 231, where the current collector 231 includes an insulating layer 2311, a first current collecting layer 2312 and a second current collecting layer 2313 respectively disposed on two opposite sides of the insulating layer 2311, and conductive layers 2314 are disposed between the first current collecting layer 2312 and the insulating layer 2311 and between the second current collecting layer 2313 and the insulating layer 2311, where the conductive layers 2314 are formed by a conductive composite layer structure formed by combining a conductive polymer and a binder. By laminating the conductive layers 2314 between the first current collecting layer 2312 and the insulating layer 2311 and between the second current collecting layer 2313 and the insulating layer 2311, the battery cell 20 can be ensured to have smaller initial resistance and a complete conductive network no matter microcracks are generated on the first current collecting layer 2312 or the second current collecting layer 2313, and therefore the purpose of optimizing the working reliability of the battery cell 20 and the battery 1 can be achieved. By providing the conductive layer 2314 formed of a conductive composite layer structure formed by compounding a conductive polymer and a binder, a better bonding force is provided between the layer structures inside the current collector 231 to prevent the insulating layer 2311 from being separated from the first current collecting layer 2312 and the second current collecting layer 2313, so that the single battery 20 and the battery 1 have better use safety.

The technical features of the embodiments described above may be arbitrarily combined, and for the sake of brevity, all possible combinations of the technical features in the embodiments described above are not described, but should be considered as being within the scope of the present specification as long as there is no contradiction between the combinations of the technical features.

The above-mentioned embodiments only express several embodiments of the present application, and the description thereof is more specific and detailed, but not construed as limiting the claims. It should be noted that, for a person skilled in the art, several variations and modifications can be made without departing from the concept of the present application, which falls within the scope of protection of the present application. Therefore, the protection scope of the present patent application shall be subject to the appended claims.

Claims (14)

1. A current collector, comprising:

an insulating layer (2311);

a first current collecting layer (2312) and a second current collecting layer (2313) which are respectively arranged at two opposite sides of the insulating layer (2311); and

a conductive layer (2314), the conductive layer (2314) being disposed between the first current collector layer (2312) and the insulating layer (2311), and/or between the second current collector layer (2313) and the insulating layer (2311).

2. The current collector of claim 1, wherein the conductive layer (2314) is stacked between the first current collecting layer (2312) and the insulating layer (2311), and between the second current collecting layer (2313) and the insulating layer (2311).

3. The current collector of claim 1, wherein the conductive layer (2314) is a conductive polymer layer.

4. The current collector of claim 1, wherein the electrical conductivity σ of the electrically conductive layer (2314) satisfies the condition: 10 ² S/m≤σ≤10 ⁷ S/m。

5. The current collector of claim 4, wherein the electrical conductivity σ of the electrically conductive layer (2314) satisfies the condition: 10 ⁵ S/m≤σ≤10 ⁶ S/m。

6. The current collector of claim 1, wherein the conductive layer (2314) is configured as a conductive composite layer compounded of a conductive polymer and a binder.

7. The collector of claim 6, wherein in the conductive layer (2314), the compounding ratio K of the binder to the conductive polymer satisfies the condition: k is more than 0 percent and less than or equal to 20 percent.

8. The current collector of claim 7, wherein the compounding ratio K of the binder to the conductive polymer satisfies the condition: k is more than or equal to 1 percent and less than or equal to 2 percent.

9. The current collector of claim 1, wherein the thickness H of the conductive layer (2314) satisfies the condition: h is more than or equal to 0.1um and less than or equal to 10um.

10. The current collector of claim 9, wherein the thickness H of the conductive layer (2314) satisfies the condition: h is more than or equal to 0.2um and less than or equal to 1um.

11. A pole piece comprising a current collector according to any one of claims 1 to 9.

12. An electrode assembly comprising a pole piece as claimed in claim 11.

13. A battery cell comprising the electrode assembly of claim 12.

14. A battery comprising a cell according to claim 13.

Images