WO2024027821A1

WO2024027821A1 - Plate, electrode assembly, battery cell, battery and electric device

Info

Publication number: WO2024027821A1
Application number: PCT/CN2023/111188
Authority: WO
Inventors: 李世松; 许宝华; 商红武; 王亚书; 李楠
Original assignee: 宁德时代新能源科技股份有限公司
Priority date: 2022-08-05
Filing date: 2023-08-04
Publication date: 2024-02-08
Also published as: CN218274642U

Abstract

The present application relates to the technical field of battery production, and specifically disclosed are a plate, an electrode assembly, a battery cell, a battery and an electric device. The plate comprises a plate body and a tab connected to the plate body; and the plate comprises a first surface and a second surface, which are arranged opposite each other, wherein the tab presents a first shape on the side where the first surface is located, and the tab presents a second shape on the side where the second surface is located, the first shape being different from the second shape. According to the plate in the present application, the tab of the plate is configured in such a way that the tab presents the first shape on the side where the first surface is located and the tab presents the second shape on the side where the second surface is located, and the first surface and the second surface of the plate are distinguished by means of the difference between the first shape and the second shape, so as to improve the convenience of the plate in the processing thereof.

Description

Pole pieces, electrode components, battery cells, batteries and electrical devices

Cross-references to related applications

This application claims priority and benefit from the following patent applications, the entire contents of which are incorporated into this application by reference:

A Chinese patent application with application number 202222063052.6 and titled "pole pieces, electrode assemblies, battery cells, batteries and electrical devices" was submitted to the State Intellectual Property Office of China on August 5, 2022.

Technical field

The present application relates to the technical field of battery production, and in particular to a pole piece, an electrode assembly, a battery cell, a battery and an electrical device.

Background technique

With the development of new energy, more and more fields use new energy as power. Due to its advantages such as high energy density, rechargeability, safety and environmental protection, power batteries are widely used in new energy vehicles, consumer electronics, energy storage systems and other fields.

With the widespread application of power batteries, it is a future demand goal to achieve asymmetric coating on the two oppositely arranged surfaces of the pole piece in terms of weight or function. In the existing pole piece, the two oppositely arranged surfaces cannot be effectively distinguished. .

Contents of the invention

In view of the above problems, the present application provides a pole piece, electrode assembly, battery cell, battery and electrical device, which solves the problem that two oppositely arranged surfaces of the existing pole piece cannot be effectively distinguished.

The first aspect of this application proposes a pole piece. The pole piece includes a pole piece body and a pole tab connected to the pole piece body. The pole piece includes a first surface and a second surface arranged oppositely. On one side of the first surface, the pole tab presents a first shape, and on one side of the second surface, the pole tab presents a second shape, and the first shape is different from the second shape.

According to the pole piece of the present application, the pole tabs of the pole piece are arranged so that the pole tabs present a first shape on one side of the first surface and a second shape on one side of the second surface, and the first shape and the third The first and second sides of the pole piece are distinguished by different shapes to improve the convenience during pole piece processing.

In some embodiments of the present application, the pole lug is provided with at least one identifiable structure, and the pole lug presents the first shape on one side of the first surface through the at least one identifiable structure, The tab assumes the second shape on one side of the second face via the at least one identifiable structure. The identifiable structure is provided on the pole lug, and the identifiable structure is used to enable the pole lug to present a first shape on one side of the first surface and a second shape on one side of the second surface, and according to the first shape and the second shape The difference distinguishes the first side and the second side of the pole piece. By providing an identifiable structure, on the basis of effectively distinguishing the first surface and the second surface of the pole piece, the structure of the pole tab can be simplified, and the manufacturing process of the pole piece can be simplified, thereby improving production efficiency.

In some embodiments of the present application, the identifiable structure is a notch structure, a hole structure or a protruding structure. By setting the identifiable structure as one of a notch structure, a hole structure, and a convex structure, the convenience of processing the identifiable structure is improved, and the production cycle time is improved.

In some embodiments of the present application, the identifiable structure is a notch structure formed on the edge of the tab, and on one side of the first surface, the notch structure is located at the first position of the tab, On one side of the second surface, the notch structure is located at a second position of the tab, and the first position is different from the second position. The identifiable structure is arranged as a notch structure. The notch structure is located at a first position on one side of the first side and at a second position on the second side. Through the difference between the first position and the second position, the first side and the second side are separated. Second side distinction. The notch structure has strong recognizability and is simple in structure, making it easy to process and manufacture.

In some embodiments of the present application, the number of the identifiable structures that are the gap structures is One, the pole tab has an L-shaped structure. The pole tab is set as an identifiable structure with a notch structure, so that the pole tab is arranged in an L shape, and one side of the L-shaped structure is connected to the pole piece body, and the other side of the L-shaped structure is suspended. The pole tab is presented on the first side. The shape is one of a positive L shape and an inverted L shape. The shape of the pole lug on the second side is the other of a positive L shape and an inverted L shape. The L-shaped structure can be used to quickly and accurately identify the first side and the second side. faces, thus improving the accuracy of first and second face recognition.

In some embodiments of the present application, at least one of the first surface and the second surface is provided with a marker, and the marker is provided on the tab, so that the first surface and the second sides exhibit different physical properties relative to each other, the different physical properties being different in at least one of color, shape, and size. On the basis that the pole lug has an identifiable structure, by setting an identifier on at least one of the first surface and the second surface of the pole piece, the first surface and the second surface have at least one of color, shape and size. The two sides present different physical properties. The use of different physical properties further improves the convenience of distinguishing the first side and the second side of the pole piece, thereby speeding up the production cycle and thereby improving the production efficiency.

In some embodiments of the present application, the first surface is provided with a first identifier, and the second surface is provided with a second identifier. The first identifier and the second identifier are different in color and shape. and differ in at least one aspect of size. A first marker is provided on the first surface, and a second marker is provided on the second surface. The first marker and the second marker are different in at least one aspect of color, shape and size, so that it can be realized Quick and accurate identification of the first and second sides of the pole piece.

In some embodiments of the present application, the first identifier is a coating or glue layer provided on the tab;

And/or, the second identifier is a coating or glue layer provided on the tab.

Setting the marker as a coating or glue layer facilitates the placement of the marker on the pole piece, thereby improving the convenience of setting the marker.

In some embodiments of the present application, the first identifier has a first identifiable color, the second identifier has a second identifiable color, and the first identifiable color and the second identifiable color The colors are different. Through the difference between the first identifiable color and the second identifiable color, the first surface and the third surface are realized The distinction between the two sides further improves the convenience in the identification process.

In some embodiments of the present application, one of the first identifier and the second identifier is continuously distributed on the tab, and the other of the first identifier and the second identifier is One is distributed at intervals on the pole lug. The first marker and the second marker are arranged in different distribution modes, and different distribution modes are used to distinguish the two sides of the pole piece, which also realizes rapid differentiation of the pole pieces, effectively improving the convenience of processing.

In some embodiments of the present application, both the first marker and the second marker are continuously distributed on the pole piece, and in the width direction of the pole piece, the size of the first marker is the same as that of the second marker. The second markers are different in size. By adjusting the width of the marker on the two opposite surfaces of the pole piece, the processing of placing the marker on the pole piece is facilitated, thereby improving production efficiency.

In some embodiments of the present application, both the first identifier and the second identifier are continuously distributed on the pole piece, and in the width direction of the pole piece, the position of the first identifier is consistent with The positions of the second markers are different. By adjusting the positions of the markers on the opposite sides of the pole pieces, the markers can be processed on the pole pieces while unifying the size of the markers, thereby improving production efficiency.

In some embodiments of the present application, the size of the first marker is different from the size of the second marker in the direction from the first surface to the second surface. By adjusting the thickness of the marker on the two opposite surfaces of the pole piece, the processing of placing the marker on the pole piece is facilitated, thereby improving production efficiency.

In some embodiments of the present application, the marker contains an insulating material. An insulating material is provided in the marker, so that the location of the marker can be insulated, thereby reducing short circuits between the marker and other components and improving the safety of use.

The second aspect of the present application proposes an electrode assembly, including a positive electrode sheet, a negative electrode sheet, and an isolation film disposed between the positive electrode sheet and the negative electrode sheet, and at least one of the positive electrode sheet and the negative electrode sheet adopts the above method. The pole piece.

A third aspect of the present application proposes a battery cell including the electrode assembly as described above.

A fourth aspect of the present application proposes a battery, including the battery cell as described above.

A fifth aspect of the present application provides an electrical device, including a battery as described above, where the battery is used to provide electrical energy.

The above description is only an overview of the technical solutions of the present application. In order to have a clearer understanding of the technical means of the present application, they can be implemented according to the content of the description, and in order to make the above and other purposes, features and advantages of the present application more obvious and understandable. , the specific implementation methods of the present application are specifically listed below.

Description of the drawings

Figure 1 schematically shows a structural diagram of a vehicle according to some embodiments of the present application;

Figure 2 schematically shows a structural diagram of a battery pack according to some embodiments of the present application;

Figure 3 schematically shows a structural diagram of a battery module according to some embodiments of the present application;

Figure 4 schematically shows a structural diagram of a battery cell according to some embodiments of the present application;

Figure 5 schematically shows a structural diagram of an electrode assembly according to some embodiments of the present application;

Figure 6 schematically shows a structural diagram of a pole piece according to some embodiments of the present application;

Figure 7 schematically shows the structural diagram of the other side of the pole piece shown in Figure 6;

Figure 8 schematically shows a structural diagram of a pole piece according to some embodiments of the present application;

Figure 9 schematically shows the structural diagram of the other side of the pole piece shown in Figure 8;

Figure 10 schematically shows a structural diagram of a pole piece according to some embodiments of the present application;

Figure 11 schematically shows the structural diagram of the other side of the pole piece shown in Figure 10;

Figure 12 schematically shows a structural diagram of a pole piece according to some embodiments of the present application;

Figure 13 schematically shows the structural diagram of the other side of the pole piece shown in Figure 12;

Figure 14 schematically shows a structural diagram of a pole piece according to some embodiments of the present application;

Figure 15 schematically shows the structural diagram of the other side of the pole piece shown in Figure 14;

Figure 16 schematically shows a structural diagram of a tab according to some embodiments of the present application;

Figure 17 schematically shows a structural diagram of a tab according to some embodiments of the present application;

Figure 18 schematically shows a structural diagram of a tab according to some embodiments of the present application.

The reference numbers are as follows:
1000, vehicles;
100. Battery; 200. Controller; 300. Motor;
110. Battery module; 120. Box;
121. Part One; 122. Part Two;
10. Battery cells;
1. Shell;
2. Electrode assembly;
21. Pole piece;
21a, positive electrode piece; 21b, negative electrode piece;
211. The body of the pole piece; 212. The pole ear; 2121. The identifiable structure; 213. The first side; 214.
second side;
22. Markers;
221. The first identifier; 222. The second identifier;
23. Isolation film;
a. The length direction of the pole piece;
b. The width direction of the pole piece.

Detailed ways

The embodiments of the technical solution of the present application will be described in detail below with reference to the accompanying drawings. The following examples are only used to illustrate the technical solution of the present application more clearly, and are therefore only used as examples and cannot be used to limit the protection scope of the present application.

Unless otherwise defined, all technical and scientific terms used herein have the same meanings as commonly understood by those skilled in the technical field belonging to this application; the terms used herein are for the purpose of describing specific embodiments only and are not intended to be used in Limitation of this application; the terms "including" and "having" and any variations thereof in the description and claims of this application and the above description of the drawings are intended to cover non-exclusive inclusion.

In the description of the embodiments of this application, the technical terms "first", "second", etc. are only used to distinguish different objects, and cannot be understood as indicating or implying the relative importance or implicitly indicating the quantity or specificity of the indicated technical features. Sequence or priority relationship. In the description of the embodiments of this application, "plurality" means two or more, unless otherwise explicitly and specifically limited.

Reference herein to "an embodiment" means that a particular feature, structure or characteristic described in connection with the embodiment can be included in at least one embodiment of the present application. The appearances of this phrase in various places in the specification are not necessarily all referring to the same embodiment, nor are separate or alternative embodiments mutually exclusive of other embodiments. Those skilled in the art understand, both explicitly and implicitly, that the embodiments described herein may be combined with other embodiments.

In the description of the embodiments of this application, the term "and/or" is only an association relationship describing associated objects, indicating that there can be three relationships, such as A and/or B, which can mean: A exists alone, and A exists simultaneously and B, there are three cases of B alone. In addition, the character "/" in this article generally indicates that the related objects are an "or" relationship.

In the description of the embodiments of this application, the term "multiple" refers to more than two (including two). Similarly, "multiple groups" refers to two or more groups (including two groups), and "multiple pieces" refers to It is more than two pieces (including two pieces).

In the description of the embodiments of this application, the technical terms "center", "longitudinal", "transverse", "length", "width", "thickness", "upper", "lower", "front", "back", "left", "right" and "vertical" The orientation or positional relationships indicated by "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential", etc. are based on those shown in the accompanying drawings. The orientation or positional relationship is only for the convenience of describing the embodiments of the present application and simplifying the description. It does not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the implementation of the present application. Example limitations.

In the description of the embodiments of this application, unless otherwise clearly stated and limited, technical terms such as "installation", "connection", "connection" and "fixing" should be understood in a broad sense. For example, it can be a fixed connection or a removable connection. Disassembly and connection, or integration; it can also be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium; it can be an internal connection between two components or the interaction between two components. For those of ordinary skill in the art, the specific meanings of the above terms in the embodiments of this application can be understood according to specific circumstances.

At present, judging from the development of the market situation, the application of power batteries is becoming more and more extensive. Power batteries are not only used in energy storage power systems such as hydropower, thermal power, wind power and solar power stations, but are also widely used in electric vehicles such as electric bicycles, electric motorcycles and electric cars, as well as in many fields such as military equipment and aerospace. . As the application fields of power batteries continue to expand, their market demand is also constantly expanding.

In the existing technology, achieving asymmetric coating on the two oppositely arranged surfaces of the pole piece in terms of weight or function is a future demand goal. Therefore, it is necessary to distinguish the two oppositely arranged surfaces of the pole piece during the pole piece processing process. more important link. In the existing technology, only defects on the surface of the pole piece can be identified, and the two oppositely arranged surfaces of the pole piece cannot be distinguished. Therefore, the problem of how to effectively distinguish the two oppositely arranged surfaces of the pole piece has become a skill in the art. Technical problems that personnel urgently need to solve.

In order to solve the problem of effectively distinguishing two oppositely arranged surfaces of the pole piece, in this application, the tabs of the pole piece are arranged so that the tabs present a first shape on one side of the first surface and a first shape on the second side. One side of the pole piece presents a second shape, and the first side and the second side of the pole piece are distinguished by the difference between the first shape and the second shape, so as to improve convenience in the pole piece processing process.

The battery cells involved in the embodiments of the present application can be, but are not limited to, used in electrical devices such as vehicles, ships, or aircrafts. A power supply system that includes the battery cells, batteries, etc. involved in this application to form the electrical device can be used.

In the embodiments of this application, the electrical devices that use batteries as power sources can be, but are not limited to, mobile phones, tablets, laptops, electric toys, power tools, battery cars, electric cars, ships, spacecraft, etc. Among them, electric toys can include fixed or mobile electric toys, such as game consoles, electric car toys, electric ship toys, electric airplane toys, etc., and spacecraft can include airplanes, rockets, space shuttles, spaceships, etc.

It should be understood that the technical solutions described in the embodiments of the present application are not limited to the batteries and electrical equipment described above, but can also be applied to all batteries including boxes and electrical equipment using batteries. However, for the sake of simplicity of description, the following embodiments take electric vehicles as examples for description.

Please refer to FIG. 1 , which is a schematic structural diagram of a vehicle 1000 provided by some embodiments of the present application. The vehicle 1000 may be a fuel vehicle, a gas vehicle or a new energy vehicle, and the new energy vehicle may be a pure electric vehicle, a hybrid vehicle or an extended-range vehicle, etc. The battery 100 is disposed inside the vehicle 1000 , and the battery 100 may be disposed at the bottom, head, or tail of the vehicle 1000 . The battery 100 may be used to power the vehicle 1000 , for example, the battery 100 may serve as an operating power source for the vehicle 1000 . The vehicle 1000 may also include a controller 200 and a motor 300 . The controller 200 is used to control the battery 100 to provide power to the motor 300 , for example, for starting, navigating and driving the vehicle 1000 .

In some embodiments of the present application, the battery 100 can not only be used as an operating power source for the vehicle 1000 , but also can be used as a driving power source for the vehicle 1000 , replacing or partially replacing fuel or natural gas to provide driving power for the vehicle 1000 .

In order to meet different power requirements, the battery 100 may include multiple battery cells. A battery cell refers to the smallest unit that constitutes a battery module or battery pack. Multiple battery cells may be connected in series and/or in parallel via electrode terminals for various applications. The battery 100 mentioned in this application includes a battery module or a battery pack. Among them, multiple battery cells can be connected in series, parallel, or mixed. Hybrid refers to a mixture of series and parallel. The battery 100 may also be called a battery pack. In the embodiment of the present application, multiple battery cells can be directly formed into a battery pack, or a battery module can be formed first, and then the battery module can be formed into a battery pack.

FIG. 2 shows a schematic structural diagram of a battery 100 according to an embodiment of the present application. In FIG. 2 , the battery 100 may include a plurality of battery modules 110 and a case 120 . The plurality of battery modules 110 are accommodated inside the case 120 . The box 120 is used to accommodate the battery cells or battery modules 110 to reduce the impact of liquid or other foreign matter on the charging or discharging of the battery cells. The box 120 may be a single cuboid, a simple three-dimensional structure such as a cylinder or a sphere, or a complex three-dimensional structure composed of a combination of simple three-dimensional structures such as a cuboid, a cylinder or a sphere, which is not limited in the embodiments of the present application. The material of the box body 120 may be alloy materials such as aluminum alloy, iron alloy, etc., or may be polymer materials such as polycarbonate, polyisocyanurate foam, or composite materials such as glass fiber and epoxy resin. The embodiments of this application are This is not limiting either.

In some embodiments, as shown in FIG. 2 , the box 120 may include a first part 121 and a second part 122 . The first part 121 and the second part 122 cover each other. The first part 121 and the second part 122 jointly define a space for accommodating battery cells. The second part 122 may be a hollow structure with one end open, and the first part 121 may be a plate-like structure. The first part 121 covers the open side of the second part 122 so that the first part 121 and the second part 122 jointly define a space for accommodating the battery. Single space; the first part 121 and the second part 122 may also be hollow structures with one side open, and the open side of the first part 121 covers the open side of the second part 122.

FIG. 3 shows a schematic structural diagram of a battery module 110 according to an embodiment of the present application. In Figure 3, the battery module 110 may include multiple battery cells 10. The multiple battery cells 10 may be first connected in series, parallel, or mixed to form the battery module 110. The multiple battery modules 110 may then be connected in series, parallel, or mixed. form a battery. In this application, the battery cell 10 may include a lithium-ion battery, a sodium-ion battery, a magnesium-ion battery, etc., which is not limited in the embodiments of this application. The battery cell 10 may be in the shape of a cylinder, a flat body, a rectangular parallelepiped, or other shapes, and the embodiments of the present application are not limited thereto. Battery cells 10 are generally divided into three types according to packaging methods: cylindrical battery cells, rectangular battery cells and soft-pack battery cells, and the embodiments of the present application are not limited thereto.

FIG. 4 shows a schematic structural diagram of a battery cell 10 according to an embodiment of the present application. The battery cell 10 includes a case 1 , an end cap assembly 3 and an electrode assembly 2 .

The end cover assembly 3 includes an end cover 31 . The end cover 31 refers to a component that covers the opening of the housing 1 to isolate the internal environment of the battery cell 10 from the external environment. Without limitation, the shape of the end cap 31 can be adapted to the shape of the housing 1 to fit the housing 1 . Optionally, the end cap 31 can be made of a material with a certain hardness and strength (such as aluminum alloy). In this way, the end cap 31 is less likely to deform when subjected to extrusion and collision, so that the battery cell 10 can have higher durability. Structural strength and safety performance can also be improved. The end cap 31 can also be made of various materials, such as copper, iron, aluminum, stainless steel, aluminum alloy, plastic, etc., which are not particularly limited in the embodiment of the present application. In some embodiments, an insulating member may also be provided inside the end cover 31 , and the insulating member may be used to isolate the electrical connection components in the housing 1 from the end cover 31 to reduce the risk of Risk of short circuit. For example, the insulating member may be plastic, rubber, etc.

The case 1 is a component used to cooperate with the end cover 31 to form an internal environment of the battery cell 10 , wherein the formed internal environment can be used to accommodate the electrode assembly 2 , electrolyte and other components. The housing 1 and the end cover 31 may be independent components. An opening may be provided in the housing 1 and the end cover 31 covers the opening to form the internal environment of the battery cell 10 . Without limitation, the end cover 31 and the housing 1 can also be integrated. Specifically, the end cover 31 and the housing 1 can form a common connection surface before other components are put into the housing. When it is necessary to encapsulate the inside of the housing 1 When, the end cover 31 is closed with the housing 1 again. The housing 1 can be of various shapes and sizes, such as rectangular parallelepiped, cylinder, hexagonal prism, etc. Specifically, the shape of the housing 1 can be determined according to the specific shape and size of the battery core assembly. The housing 11 can be made of a variety of materials, such as copper, iron, aluminum, stainless steel, aluminum alloy, plastic, etc., which are not particularly limited in the embodiment of the present application.

As shown in FIG. 5 , the electrode assembly 2 is a component in the battery cell 10 where electrochemical reactions occur. One or more electrode assemblies 2 may be contained within the housing 1 . The electrode assembly 2 is mainly composed of pole pieces (positive pole piece 21a and negative pole piece 21b) wound (one end of a pole piece is fixed as a whole, and the other end is wound in one direction with one end as the center of the circle) or stacked (the stacking width is set to stack The width of the electrode is folded back and forth to realize the stacking of the electrode sheets), and a separator is usually provided between the positive electrode sheet 21a and the negative electrode sheet 21b. The portions of the pole pieces (positive pole piece 21a and negative pole piece 21b) that contain active material constitute the pole piece body of the battery assembly, and the portions of the positive pole piece 21a and negative pole piece 21b that do not contain active material each constitute pole tabs. The positive pole tab and the negative pole tab can be located together at one end of the pole piece body or respectively at both ends of the pole piece body. During the charging and discharging process of the battery, the positive active material and negative active material react with the electrolyte, and the tabs are connected to the electrode terminals to form a current loop.

The pole piece 21 usually includes a current collector and film layers disposed on two surfaces of the current collector (the two surfaces refer to two surfaces with opposite thickness directions). The film layers include positive active materials or negative active materials (when the pole piece 21 is When the electrode piece 21 is a positive electrode piece 21a, the film layer includes a positive electrode active material; when the electrode piece 21 is a negative electrode piece 21b, the film layer includes a negative electrode active material).

The current collector can be a metal foil or a composite current collector. As the metal foil, aluminum foil can be used. complex The collected fluid may include a polymer material base layer and a metal layer formed on at least one surface of the polymer material base layer. The composite current collector can be formed by forming metal materials (aluminum, aluminum alloys, nickel, nickel alloys, titanium, titanium alloys, silver and silver alloys, etc.) on polymer material substrates (such as polypropylene (PP), polyterephthalate It is formed on substrates such as ethylene glycol ester (PET), polybutylene terephthalate (PBT), polystyrene (PS), polyethylene (PE), etc.).

The positive active material may include at least one of the following materials: an olivine-structured lithium-containing phosphate, a lithium transition metal oxide, and their respective modified compounds. However, the present application is not limited to these materials, and other traditional materials that can be used as positive electrode active materials of batteries can also be used. Only one type of these positive electrode active materials may be used alone, or two or more types may be used in combination. Examples of lithium transition metal oxides may include, but are not limited to, lithium cobalt oxide (such as LiCoO2), lithium nickel oxide (such as LiNiO2), lithium manganese oxide (such as LiMnO2, LiMn2O4), lithium nickel cobalt oxide, lithium Manganese cobalt oxide, lithium nickel manganese oxide, lithium nickel cobalt manganese oxide (such as LiNi1/3Co1/3Mn1/3O2 (can also be abbreviated to NCM333), LiNi0.5Co0.2Mn0.3O2 (can also be abbreviated to NCM523), LiNi0 .5Co0.25Mn0.25O2 (can also be abbreviated to NCM211), LiNi0.6Co0.2Mn0.2O2 (can also be abbreviated to NCM622), LiNi0.8Co0.1Mn0.1O2 (can also be abbreviated to NCM811), lithium nickel cobalt aluminum oxide (such as LiNi0.85Co0.15Al0.05O2) and at least one of its modified compounds, etc. Examples of lithium-containing phosphates with an olivine structure may include but are not limited to lithium iron phosphate (such as LiFePO4 (also referred to as LFP) ), at least one of composite materials of lithium iron phosphate and carbon, lithium manganese phosphate (such as LiMnPO4), composite materials of lithium manganese phosphate and carbon, lithium iron manganese phosphate, and composite materials of lithium iron manganese phosphate and carbon.

As the negative active material, negative active materials for batteries known in the art can be used. As an example, the negative active material may include at least one of the following materials: artificial graphite, natural graphite, soft carbon, hard carbon, silicon-based materials, tin-based materials, lithium titanate, and the like. The silicon-based material may be selected from at least one of elemental silicon, silicon oxide compounds, silicon carbon composites, silicon nitrogen composites and silicon alloys. The tin-based material may be selected from at least one of elemental tin, tin oxide compounds and tin alloys. However, the present application is not limited to these materials, and other traditional materials that can be used as battery negative electrode active materials can also be used. These negative Only one type of extremely active material may be used alone, or two or more types of extremely active materials may be used in combination.

In some embodiments of this application, as shown in Figures 5 to 18, this application proposes a pole piece 21. The pole piece 21 includes a pole piece body 211 and a pole tab 212 connected to the pole piece body 211. 21 includes a first surface 213 and a second surface 214 arranged oppositely. On one side of the first surface 213, the pole tab 212 presents a first shape, and on one side of the second surface 214, the pole tab 212 presents a second shape. One shape is different from the second shape.

Specifically, the pole piece 21 has two large surfaces, and the two large surfaces are arranged on opposite sides of the pole piece 21 . The first surface 213 is one of the large surfaces, and the second surface 214 is the other large surface. The pole piece body 211 and the pole tab 212 of the pole piece 21 are located on the same plane, and the pole tab 212 is formed on the edge of the pole piece body 211 (the pole tab 212 and the pole piece body 211 can be an integrated structure, or can be processed separately and then welded, etc. The pole tab 212 and one side of the pole piece body 211 constitute one large surface of the pole piece 21 , and the pole tab 212 and the other side of the pole piece body 211 constitute another large surface of the pole piece 21 . During the processing of the counter pole piece 21, when the processing personnel or identification equipment observe the pole tabs 212 on one side of the first surface 213 of the pole piece 21, the first pole tabs 212 exhibit the first shape, and the processing personnel or identification equipment When the pole tab 212 is observed from the side of the second surface 214 of the pole piece 21 , the first pole tab 212 exhibits a second shape. The difference between the first shape and the second shape is used to distinguish the first surface of the pole piece 21 213 and 214 on the second side.

The pole tabs 212 of the pole piece 21 are arranged so that the pole tabs 212 present a first shape on one side of the first surface 213 and a second shape on one side of the second surface 214, and through the first shape and the second shape The difference between the first surface 213 and the second surface 214 of the pole piece 21 is used to improve the convenience during the processing of the pole piece 21.

It should be understood that the first shape is different from the second shape. For example, the first shape is a positive L-shape (as shown in Figure 14), the second shape is an inverted L-shape (as shown in Figure 15), or the first shape is Positive T shape, the second shape is an inverted T shape, the first shape is a C shape with the opening facing upward, the second shape is a C shape with the opening facing downward, etc.

In some embodiments of the present application, as shown in Figures 14 to 18, the tab 212 is provided with at least An identifiable structure 2121, the pole lug 212 presents a first shape on one side of the first surface 213 through at least one identifiable structure 2121, and the pole lug 212 presents a second shape on one side of the second surface 214 through at least one identifiable structure 2121. shape.

Specifically, the identifiable structure 2121 is a structure formed on the tab 212. The identifiable structure 2121 can be processed simultaneously with the tab 212, or can be processed separately on the tab 212. During the processing of the pole piece 21 of the pole lug 212 with the identifiable structure 2121, the identifiable structure 2121 can be observed, and the shape presented by the identifiable structure 2121 on one side of the first face 213 is consistent with the shape on the second face 214. The purpose of distinguishing the first side 213 and the second side 214 is achieved by different shapes on one side.

The identifiable structure 2121 is used to enable the pole lug 212 to present a first shape on one side of the first surface 213 and a second shape on one side of the second surface 214, and to align the poles according to the difference between the first shape and the second shape. A first side 213 and a second side 214 of the sheet 21 are distinguished. By providing the identifiable structure 2121, on the basis of effectively distinguishing the first surface 213 and the second surface 214 of the pole piece 21, the structure of the pole tab 212 can be simplified, and the manufacturing process of the pole piece 21 can be simplified, thereby improving production efficiency. .

It should be noted that the number of identifiable structures 2121 on the tab 212 includes but is not limited to one. When the number of identifiable structures 2121 is one, one identifiable structure 2121 is provided on the tab 212 so that the tab 212 The first shape is present on the first surface 213, and the second shape is presented on the second surface 214; when the number of identifiable structures 2121 is at least two, at least two identifiable structures 2121 are provided on the tab 212, so that The tab 212 exhibits a first shape on a first side 213 and a second shape on a second side 214 .

In some embodiments of the present application, the identifiable structure 2121 is a notch structure, a hole structure or a protruding structure.

The identifiable structure 2121 can be arranged on the edge, middle or other position of the pole tab 212. The specific position can be set according to specific processing needs. When the pole piece 21 is turned over with its length direction or width direction as the axis, the identifiable structure 2121 It suffices that the first shape presented on one side of the first surface 213 is different from the shape presented on one side of the second surface 214 .

In this application, identifiable structures 2121 include but are not limited to gap structures (as shown in Figures 14, 15, 16, 17 or 18), hole structure or protruding structure, the specific structural form of the identifiable structure 2121 can be specifically set according to needs.

For example, when the identifiable structure 2121 is a notch structure, the notch structure is formed on the edge of the pole piece 212, and when the pole piece 21 is flipped with the width direction as the axis, the pole piece 212 with the notch structure is flipped relative to the pole piece 21 The axis has an asymmetric structure, and when the pole piece 21 is flipped along its length direction, the pole tab 212 with the notch structure has an asymmetric structure relative to the flip axis of the pole piece 21 (for example, the pole tab 212 with the notch structure can L-shaped structure or C-shaped structure, etc.).

For example, when the identifiable structure 2121 is a hole structure, the hole structure is formed on the pole tab 212, and when the pole piece 21 is flipped with its width direction as the axis, the pole tab 212 with the hole structure is flipped relative to the pole piece 21 The axis has an asymmetric structure, and when the pole piece 21 is flipped with its length direction as the axis, the pole tab 212 with a hole structure has an asymmetric structure relative to the flip axis of the pole piece 21 (for example, the hole structure can be a Y-shaped hole, T-shaped hole, L-shaped hole or C-shaped hole, etc.).

For example, when the identifiable structure 2121 is a protruding structure, the protruding structure is formed on the pole tab 212, and when the pole piece 21 is turned over with its width direction as the axis, the pole tab 212 with the protruding structure is relative to the pole piece. The flip axis of pole piece 21 has an asymmetric structure, and when the pole piece 21 flips with its length direction as the axis, the pole lug 212 with a raised structure has an asymmetric structure relative to the flip axis of the pole piece 21 (for example, with a raised structure The pole tab 212 can be a T-shaped structure or a 7-shaped structure, etc.).

By configuring the identifiable structure 2121 into one of a notch structure, a hole structure, and a protruding structure, the convenience of processing the identifiable structure 2121 is improved, and the production cycle time is improved.

It should be noted that, as shown in Figure 18, when the pole lug 212 has a rectangular structure, the identifiable structure 2121 can also be a circular chamfer structure formed on one corner of the rectangular structure, and the circular chamfer is used to The difference between the position on one side of the surface 213 and the position on one side of the second surface 214 realizes the distinction between the first surface 213 and the second surface 214 .

In some embodiments of the present application, the identifiable structure 2121 is a notch structure formed on the edge of the tab 212. On one side of the first surface 213, the notch structure is located at the first position of the tab 212 and on the second side 214. On one side, the notch structure is located at the second position of the pole lug 212, and the first position is different from the second position. same.

Specifically, the identifiable structure 2121 is set as a notch structure. The notch structure is located at a first position on one side of the first surface 213 and at a second position on the second surface 214. Through the difference between the first position and the second position, The first side 213 and the second side 214 are distinguished. The notch structure has strong recognizability and is simple in structure, making it easy to process and manufacture.

It should be understood that when the pole piece 21 is turned over, the pole tab 212 with the notch structure is flipped synchronously with the pole piece 21. When one side of the first surface 213 faces the processing personnel or identification equipment, the notch structure is located on the pole tab 212. The first position of the pole piece 21 is flipped with its length direction or width direction as the axis, and the notch structure is located at the second position of the pole tab 212. The difference between the first position and the second position is used to distinguish the first position of the pole piece 21. Side 213 and second side 214.

It should be noted that the notch structure may be a rectangular notch formed on the pole tab 212 or an arc-shaped notch formed on the pole tab 212 .

In some embodiments of the present application, the number of identifiable structures 2121 is one notch structure, and the tab 212 has an L-shaped structure.

Specifically, as shown in Figures 14 to 17, the pole tab 212 is provided with an identifiable structure 2121 that is a notch structure, so that the pole tab 212 is arranged in an L shape, and one side of the L-shaped structure is connected to the pole piece body 211, L The other side of the structure is suspended. The shape of the tab 212 on the first side 213 is one of a positive L shape and an inverted L shape. The shape of the tab 212 on the second side 214 is a positive L shape or an inverted L shape. Another one of the two types, the L-shaped structure can be used to quickly and accurately identify the first surface 213 and the second surface 214, thereby improving the accuracy of identifying the first surface 213 and the second surface 214.

In some embodiments of the present application, as shown in FIGS. 6 and 7 , at least one of the first surface 213 and the second surface 214 is provided with an identifier 22 , and the identifier 22 is provided on the tab 212 so as to The first side 213 and the second side 214 are caused to exhibit different physical properties relative to each other, and the different physical properties are different in at least one of color, shape, and size.

Specifically, on the basis that the pole lug 212 has an identifiable structure 2121, by setting the identifier 22 on at least one of the first surface 213 and the second surface 214 of the pole piece 21, the first surface 213 and the second surface 214 are The second surface 214 exhibits different physical properties in at least one aspect of color, shape and size. The use of different physical properties further improves the convenience of distinguishing the first surface 213 and the second surface 214 of the pole piece 21, thereby making The pace of production has been accelerated, thereby improving production efficiency.

In some embodiments of the present application, the first surface 213 is provided with a first identifier 221, and the second surface 214 is provided with a second identifier 222. The first identifier 221 and the second identifier 222 are different in color, shape and size. are different in at least one aspect.

Specifically, markers 22 are provided on two opposite sides of the pole lug 212 , that is, the first marker 221 is provided on the first surface 213 , the second marker 222 is provided on the second surface 214 , and the first marker 222 is provided on the second surface 214 . The surface 213 presents a first physical feature through the first marker 221, and the second surface 214 presents a second physical feature through the second marker 222. The first marker 221 and the second marker 222 are used in color, shape and size. At least one of them is different, so that the first physical characteristic is different from the second physical characteristic. Through the difference in physical characteristics, the first surface 213 and the second surface 214 of the pole piece 21 can be quickly and accurately identified.

It should be understood that the first identifier 221 and the second identifier 222 are different in at least one aspect of color, shape, and size. The first identifier 221 and the second identifier 222 may be completely different in color, shape, and size. It may also be that the first identifier 221 and the second identifier 222 are partly the same in color, shape, and size (for example, as shown in FIGS. 6 and 7 , on the premise that the first identifier 221 and the second identifier 222 have the same shape and size, The colors of the two markers 222 are different; for example, as shown in Figures 8 and 9, under the premise of the same color and size, the shapes of the first marker 221 and the second marker 222 are different; for example, as shown in Figures 10 to 9 As shown in 11, on the premise of the same color and shape, the first marker 221 and the second marker 222 have different sizes; for example, on the premise of the same color, the shapes of the first marker 221 and the second marker 222 and different sizes; for example, under the premise of the same shape, the color and size of the first identifier 221 and the second identifier 222 are different; for example, under the premise of the same size, the first identifier 221 and the second identifier 222 different colors and shapes).

In some embodiments of the present application, the first identifier 221 is a coating or glue layer provided on the tab 212;

And/or, the second identifier 222 is a coating or glue layer provided on the tab 212 .

Specifically, the marker 22 may be a coating provided on the tab 212. The coating is a structure formed on the tab 212 (the first surface 213 and/or the second surface 214) using a coating process, so that the coating can be The layers cause the first side 213 and the second side 214 of the pole piece 21 to exhibit different physical properties in at least one of color, shape and size.

The marker 22 may also be a glue layer provided on the tab 212. The glue layer is a structure provided on the tab 212 (the first side 213 and/or the second side 214) through a gluing or pasting process to pass through. The glue layer causes the first surface 213 and the second surface 214 of the pole piece 21 to exhibit different physical properties in at least one aspect of color, shape and size.

In this application, the marker 22 is provided as a coating or glue layer to facilitate the placement of the marker 22 on the tab 212, thereby improving the convenience of setting the marker 22.

It should be understood that setting the marker 22 as a coating or glue layer can effectively reduce the increase in the thickness of the pole tab 212 while distinguishing the two opposite sides of the pole piece 21 so that the pole piece 21 forms an electrode assembly. 2, the space occupied by the tab 212 is reduced.

In addition, the connection strength between the marker 22 and the tab 212, which is a coating or glue layer, is high, which can effectively reduce the situation that the opposite sides of the pole piece 21 cannot be effectively identified due to the falling off of the marker 22.

In some embodiments of the present application, the first identifier 221 has a first identifiable color, the second identifier 222 has a second identifiable color, and the first identifiable color and the second identifiable color are different colors.

Specifically, through the difference between the first identifiable color and the second identifiable color, the first surface 213 and the second surface 214 are distinguished, thereby improving convenience in the identification process.

It should be pointed out that the first marker 221 contains a first color-developing substance, the first marker 221 can present a first identifiable color through the first color-developing substance, and the second marker 222 contains a second color-developing substance, The first marker 221 can present a second identifiable color through the second color-developing substance, and the first identifiable color and the second identifiable color are different in color.

A color-developing substance refers to a substance that can cause the marker 22 to present an identifiable color through its own physical properties. The first color-developing substance and the second color-developing substance can exhibit two different colors of identifiable colors. Two different identifiable colors are used to distinguish the first side 213 and the second side 214 of the pole piece 21 .

Further, the first color-developing substance enables the first identifier 221 to present a first identifiable color, the second color-developing substance enables the second identifier 222 to exhibit a second identifiable color, and the first identifiable color and the second identifiable color The colors of the identifiable colors are different. Through the difference between the first identifiable color and the second identifiable color, the first side 213 and the second side 214 are distinguished, thereby improving the convenience in the identification process.

Specifically, the first color-developing substance in the first marker 221 can exhibit a first identifiable color, so that the first surface 213 has the first physical property, and the second color-developing substance in the second marker 222 can exhibit a second identifiable color. The color can be identified so that the second side 214 has a second physical property, and the two sides are distinguished by having different physical properties.

In some embodiments of the present application, the first color-developing substance is a first pigment, and the second color-developing substance is a second pigment. Under visible light conditions, the colors presented by the first pigment and the second pigment are different.

Specifically, the first pigment is mixed in the first marker 221, and the second pigment is mixed in the second marker 222, so that under visible light conditions, the first surface 213 is presented by the first pigment in the first marker 221. The first identifiable color, the second surface 214 presents the second identifiable color through the second pigment in the second marker 222. The method of using pigments of different colors to distinguish the surfaces of the pole piece 21 facilitates observation and improves the polarity. The convenience in the processing of tablet 21 and the low cost of pigments can effectively reduce the manufacturing cost.

It should be understood that the first side 213 presents a first identifiable color through a first pigment, and the second side 214 presents a second identifiable color through a second pigment. For example, the first side 213 is blue, and the second side 214 is blue. Red; or the first side 213 is blue, the second side 214 is green; or the first side 213 is red, the second side 214 is gold...

In addition, both the first pigment and the second pigment are substances that can present colors under visible light conditions, so that the color of the marker 22 can be identified without specific conditions, thereby facilitating the identification operation during the production process and improving the production efficiency. beat.

It should be noted that the first pigment and the second pigment may include but are not limited to toluidine red, methyl Two of the pigments, orange or titanium dioxide, have a wide range of sources and have good color presentation effects, which can effectively meet the needs of use.

In some embodiments of the present application, the first color-developing substance is a first fluorescent substance, the second color-developing substance is a second fluorescent substance, and the first fluorescent substance and the second fluorescent substance exhibit different fluorescent colors.

Specifically, the first fluorescent material is mixed in the first marker 221, and the second fluorescent material is mixed in the second marker 222. Under preset conditions (under conditions where the fluorescent material can emit light, such as ultraviolet lamp irradiation, etc.), The first surface 213 presents a first fluorescent color through the first fluorescent material in the first marker 221, and the second surface 214 presents a second fluorescent color through the second fluorescent material in the second marker 222. Different fluorescent materials are used to The surface of the pole piece 21 is distinguished, and the performance of the fluorescent material is stable and the recognition performance is high.

It should be understood that the first side 213 presents a first fluorescent color through a first fluorescent substance, and the second side 214 presents a second fluorescent color through a second fluorescent substance. For example, the first side 213 is green and the second side 214 is red. ; Or the first side 213 is blue, the second side 214 is green; or the first side 213 is red, the second side 214 is blue...

It should be noted that the first fluorescent substance and the second fluorescent substance include but are not limited to two kinds of organic fluorescent materials such as rhodamine, coumarins, porphyrin, thiazole and their derivatives, or rare earth metals (such as Eu, Sm, etc.), alkaline earth metals (such as ZnS, etc.) and other inorganic fluorescent materials. The above inorganic or organic fluorescent materials are safe, environmentally friendly, easy to obtain materials, and are suitable for industrial applications.

In some embodiments of the present application, as shown in FIGS. 8 and 9 , one of the first identifier 221 and the second identifier 222 is continuously distributed on the tab 212 , and the first identifier 221 and the second identifier 222 are continuously distributed on the tab 212 . Another one of 222 is spaced apart on the pole lug 212 .

Specifically, the first marker 221 and the second marker 222 are arranged in different distribution modes, and different distribution modes are used to distinguish the two sides of the pole piece 21, which also realizes rapid differentiation of the pole piece 21, making processing convenient. Sexuality has been effectively improved.

It should be understood that the first identifier 221 and the second identifier 222 are distributed in different ways on the two surfaces of the tab 212. For example, as shown in Figures 8 and 9, the first identifier 221 is located at the location of the tab 212. The second markers 222 are continuously distributed on one side of the first surface 213, and the second markers 222 are distributed at intervals on the side where the tabs 212 are located on the second surface 214; or the second markers 222 are located on the second surface 214 when the tabs 212 are located. are continuously distributed on one side, and the first markers 221 are distributed at intervals on the side of the tab 212 located on the first surface 213 .

It should be pointed out that, as shown in Figure 9, a in Figure 9 is the length direction of the pole piece 21, and b is the width direction of the pole piece 21. When the first marker 221 or the second marker 222 is present on the pole tab 212, When continuously distributed, the first identifier 221 or the second identifier 222 is continuously distributed along the length direction of the pole piece 21. When the first identifier 221 or the second identifier 222 is distributed at intervals on the pole tab 212, the first identifier The objects 221 or the second markers 222 are distributed at intervals along the length direction of the pole piece 21 (the intervals may be equal or unequal).

In some embodiments of the present application, as shown in Figures 10 and 11, both the first identifier 221 and the second identifier 222 are continuously distributed on the pole piece 21. In the width direction of the pole piece 21, the first marker The size of object 221 is different from the size of second identification object 222.

Specifically, in this application, the first identifier 221 and the second identifier 222 are continuously distributed on the opposite sides of the tab 212. By placing the first identifier 221 and the second identifier 222 on the opposite sides of the tab 212, The widths of the two surfaces are set to be different to distinguish the first surface 213 and the second surface 214 of the pole piece 21 . Arranging the first marker 221 and the second marker 222 continuously facilitates the processing of the first marker 221 and the second marker 222 on the pole piece 21 , thereby improving production efficiency.

In some embodiments of the present application, as shown in FIGS. 12 and 13 , both the first identifier 221 and the second identifier 222 are continuously distributed on the pole piece 21 , and in the width direction of the pole piece 21 , the first identifier The position of object 221 is different from the position of second identification object 222.

Specifically, the first identifier 221 is provided on one side of the pole lug 212 located on the first surface 213, and the second identifier 222 is provided on one side of the pole lug 212 located on the second surface 214. The first identifier 221 and the third The two markers 222 have the same color and distribution mode. The first marker 221 has a first position in the width direction of the pole piece 21, and the second marker 222 has a second position in the width direction of the pole piece 21. Using the first position and The first side 213 and the second side 214 are distinguished by the difference in the second position.

By setting the positions of the first marker 221 and the second marker 222, and on the premise of unifying the size of the marker 22, the marker 22 is disposed on the pole piece 21, thereby improving production efficiency.

In some embodiments of the present application, the size of the first identifier 221 is different from the size of the second identifier 222 in the direction from the first surface 213 to the second surface 214 .

Specifically, in this application, the first markers 221 are continuously distributed on the side of the tab 212 located on the first surface 213, and the second markers 222 are also continuous on the side of the tab 212 located on the second surface 214. Taking the distribution as an example, by adjusting the thickness of the first marker 221 and the second marker 222 on the opposite sides of the tab 212, the processing of the first marker 221 and the second marker 222 on the tab 212 is facilitated, so that Improved production efficiency.

In some embodiments of the present application, the marker 22 contains insulating material.

Specifically, an insulating material is provided in the marker 22 so that the location of the marker 22 can be insulated to reduce short circuits between the marker 22 and other components and improve the safety of use.

It should be noted that insulating materials include, but are not limited to, modified polyphthalamide (modified PPA), polyethylene (PE), polypropylene (PP) and other materials that are resistant to low temperature, high temperature or have excellent electrical insulation properties.

The second aspect of the present application proposes an electrode assembly 2, including a positive electrode sheet 21, a negative electrode sheet 21, and a separation film 23 disposed between the positive electrode sheet 21 and the negative electrode sheet 21, and at least one of the positive electrode sheet 21 and the negative electrode sheet 21 One uses the pole piece 21 as above.

Since the electrode assembly 2 has the same technical features as the above-mentioned pole piece 21, it also has the same beneficial effects as the above-mentioned pole piece 21. The beneficial effects of the electrode assembly 2 can be specifically referred to the beneficial effects of the pole piece 21. Here, this application does not Let’s go into details.

The third aspect of the present application proposes a battery cell, including the above electrode assembly 2.

Since the battery cell has the same technical characteristics as the above-mentioned electrode assembly 2, it also has the same beneficial effects as the above-mentioned electrode assembly 2. The beneficial effects of the battery cell can be specifically referred to the beneficial effects of the electrode assembly 2. Here, this application does not Let’s go into details.

A fourth aspect of the present application proposes a battery, including the above battery cell.

Since the battery has the same technical characteristics as the above-mentioned battery cells, it also has the same beneficial effects as the above-mentioned battery cells. The beneficial effects of the battery can be specifically referred to the beneficial effects of the battery cells, and will not be described in detail here.

The fifth aspect of this application proposes an electrical device, including the above battery, and the battery is used to provide electrical energy.

Since the electrical device has the same technical characteristics as the above-mentioned battery, it also has the same beneficial effects as the above-mentioned battery. The beneficial effects of the electrical device can be specifically referred to the beneficial effects of the battery, and will not be described in detail here.

In the embodiment of the present application, as shown in Figures 5 to 18, the present application proposes a pole piece 21. The pole piece 21 includes a pole piece body 211 and a pole tab 212 connected to the pole piece body 211. 21 includes a first surface 213 and a second surface 214 arranged oppositely. On one side of the first surface 213, the pole tab 212 presents a first shape, and on one side of the second surface 214, the pole tab 212 presents a second shape. One shape is different from the second shape. The pole tabs 212 of the pole piece 21 are arranged so that the pole tabs 212 present a first shape on one side of the first surface 213 and a second shape on one side of the second surface 214, and through the first shape and the second shape The difference between the first surface 213 and the second surface 214 of the pole piece 21 is used to improve the convenience during the processing of the pole piece 21.

It should be noted that the identifiable structure 2121 may be a notch structure formed on the tab 212 or a rounded corner structure formed on the tab 212 .

Specifically, as shown in FIGS. 14 to 18 , the identifiable structure 2121 is a notch structure formed on the pole tab 212 . The pole tab 212 with the notch structure has an L-shaped structure. When viewed from the first surface 213 of the pole piece 21 When the pole piece 212 is turned on, the pole piece 212 has a positive L-shaped structure. When the pole piece 212 is viewed from the second side 214 of the pole piece 212, the pole piece 212 has an inverted L-shaped structure, so as to distinguish the first side of the pole piece 21. 213 and 214 on the second side.

In addition, the notch structure is a rectangular notch or an arc-shaped notch formed on the tab 212 .

Further, as shown in FIGS. 6 to 13 , first markers 221 and second markers 222 are respectively provided on opposite sides of the pole lug 212 . The first markers 221 and the second markers 222 are disposed on the poles. The coating or glue layer on the ear 212, the first identifier 221 and the second identifier 222 are all arranged along the length direction of the pole piece 21, wherein the first identifier 221 and the second identifier 222 can be in color, distribution mode , thickness and installation position are set to be different, so as to distinguish the first surface 213 and the second surface 214 of the pole piece 21 .

For example, as shown in FIGS. 6 and 7 , the first identifier 221 and the second identifier 222 are continuously distributed on the opposite sides of the pole piece 21 . Under the premise that the installation position, width (dimension in the width direction of the pole piece 21) and thickness (dimension in the direction from the first surface 213 to the second surface 214 of the pole piece 21) are the same, the first marker 221 The colors of the second identifier 222 are different, for example, the first identifier 221 is blue, the second identifier 222 is green, etc., so as to distinguish the first surface 213 and the second surface 214 of the pole piece 21 .

For example, as shown in FIGS. 8 and 9 , the position, width (dimension in the width direction of the pole piece 21 ), thickness (in the pole piece 21 ) of the first marker 221 and the second marker 222 on the pole piece 21 21 (dimensions in the direction from the first surface 213 to the second surface 214) and the same color, the first markers 221 are continuously distributed, and the second markers 222 are distributed at intervals, so as to distinguish the first markers 21 of the pole piece 21. Side 213 and second side 214.

For example, as shown in FIGS. 10 and 11 , the first identifier 221 and the second identifier 222 are continuously distributed on opposite sides of the pole piece 21 . Under the premise that the arrangement position and thickness (dimensions in the direction from the first surface 213 to the second surface 214 of the pole piece 21) on the piece 21 are the same, the width of the first marker 221 and the second marker 222 (in the direction of the pole piece 21) (dimensions in the width direction of the piece 21) are different, for example, the width of the first marker 221 is 0.5cm±0.05, the width of the second marker 222 is 1.0cm±0.05, etc., so as to distinguish the first surface of the pole piece 21 213 and 214 on the second side.

For example, as shown in Figures 12 and 13, the first marker 221 and the second marker 222 are on the pole piece. 21 are continuously distributed on the opposite sides of the pole piece 21. The color, width (dimension in the width direction of the pole piece 21) and thickness (dimensions from the first side 213 to the first side 213 of the pole piece 21) of the first marker 221 and the second marker 222 are Under the premise that the dimensions of the two surfaces 214 in the direction are the same, the first marker 221 and the second marker 222 are arranged in different positions on the pole piece 21. For example, the first marker 221 is set away from the pole piece body 211, and the second marker 221 is set away from the pole piece body 211. The marker 222 is placed close to the pole piece body 211 to distinguish the first surface 213 and the second surface 214 of the pole piece 21 .

For example, the first identifier 221 and the second identifier 222 are continuously distributed on the opposite sides of the pole piece 21. The color and width of the first identifier 221 and the second identifier 222 (in the width direction of the pole piece 21 On the premise that the size) and the installation position are the same, the thickness of the first marker 221 and the second marker 222 on the pole piece 21 (the size in the direction from the first surface 213 to the second surface 214 of the pole piece 21) are different. , for example, the thickness of the first marker 221 is large, and the thickness of the second marker 222 is small, etc., so as to distinguish the first surface 213 and the second surface 214 of the pole piece 21 .

Furthermore, an insulating material is provided in both the first marker 221 and the second marker 222, so that the positions of the first marker 221 and the second marker 222 can be insulated to reduce the occurrence of shorts between the marker 22 and other components. connection, which improves the safety of use.

Finally, it should be noted that the above embodiments are only used to illustrate the technical solution of the present application, but not to limit it; although the present application has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that: The technical solutions described in the foregoing embodiments can still be modified, or some or all of the technical features can be equivalently replaced; and these modifications or substitutions do not deviate from the essence of the corresponding technical solutions from the technical solutions of the embodiments of the present application. The scope shall be covered by the claims and description of this application. In particular, as long as there is no structural conflict, the technical features mentioned in the various embodiments can be combined in any way. The application is not limited to the specific embodiments disclosed herein, but includes all technical solutions falling within the scope of the claims.

Claims

A pole piece, characterized in that the pole piece includes a pole piece body and a pole tab connected to the pole piece body, and the pole piece includes a first face and a second face that are oppositely arranged, and in the first On one side of the surface, the pole tab presents a first shape, and on one side of the second surface, the pole tab presents a second shape, and the first shape is different from the second shape.
The pole piece according to claim 1, characterized in that at least one identifiable structure is provided on the pole lug, and the pole lug presents the at least one identifiable structure on one side of the first surface through the at least one identifiable structure. The first shape is provided, and the tab assumes the second shape on one side of the second face through the at least one identifiable structure.
The pole piece according to claim 2, wherein the identifiable structure is a notch structure, a hole structure or a protruding structure.
The pole piece according to claim 3, wherein the identifiable structure is a notch structure formed on the edge of the pole tab, and on one side of the first surface, the notch structure is located on the pole tab. The first position, on one side of the second surface, the notch structure is located at the second position of the tab, and the first position is different from the second position.
The pole piece according to claim 4, characterized in that the number of the identifiable structures of the notch structure is one, and the pole tab has an L-shaped structure.
The pole piece according to any one of claims 1 to 5, characterized in that at least one of the first surface and the second surface is provided with a marker, and the marker is provided on the pole. on the ear, so that the first surface and the second surface exhibit different physical properties relative to each other, and the different physical properties Characterized by being different in at least one of color, shape and size.
The pole piece according to claim 6, wherein the first surface is provided with a first identifier, the second surface is provided with a second identifier, and the first identifier and the second identifier are Objects differ in at least one of their colors, shapes, and sizes.
The pole piece according to claim 7, wherein the first marker is a coating or a glue layer provided on the pole lug;

And/or, the second identifier is a coating or glue layer provided on the tab.
The pole piece according to claim 7 or 8, characterized in that the first identifier has a first identifiable color, the second identifier has a second identifiable color, and the first identifiable color is the same as The second identifiable color is a different color.
The pole piece according to any one of claims 7 to 9, characterized in that one of the first identifier and the second identifier is continuously distributed on the pole lug, and the first identifier and the other of the second identifiers are spaced apart on the tab.
The pole piece according to claim 10, characterized in that both the first marker and the second marker are continuously distributed on the pole piece, and in the width direction of the pole piece, the first marker The size of the marker is different from the size of the second marker.
The pole piece according to claim 10 or 11, characterized in that the first marker and the second marker are continuously distributed on the pole piece, and in the width direction of the pole piece, the The position of the first identifier is different from the position of the second identifier.
The pole piece according to any one of claims 7 to 12, characterized in that, in the direction from the first surface to the second surface, the size of the first marker is the same as the size of the second marker. The sizes are different.
The pole piece according to any one of claims 6 to 13, characterized in that the marker contains an insulating material.
An electrode assembly, characterized in that it includes a positive electrode sheet, a negative electrode sheet and a separation film disposed between the positive electrode sheet and the negative electrode sheet, and at least one of the positive electrode sheet and the negative electrode sheet adopts claims 1-14 The pole piece described in any one of the above.
A battery cell, characterized by comprising the electrode assembly according to claim 15.
A battery, characterized by comprising the battery cell according to claim 16.
An electrical device, characterized by comprising the battery according to claim 17, said battery being used to provide electrical energy.