Electrode assembly, battery monomer, battery and electric equipment

Abstract

The utility model relates to an electrode assembly, a battery monomer, a battery and electric equipment, the electrode assembly comprises a pole piece main body and a compensation piece, the pole piece main body comprises a first pole piece and a second pole piece, the end part of the first pole piece and the end part of the second pole piece are respectively provided with a thickness thinning area, and the compensation piece is arranged on the outer surface of the pole piece main body; wherein in the height direction of the pole piece main body, the compensation piece comprises an edge region and a body region adjacent to the edge region; the thickness of the edge area is larger than that of the body area, and the edge area covers the thickness reduction area. The battery monomer comprises a shell, an end cover assembly and the electrode assembly, the shell is provided with an opening, the end cover assembly covers the opening, and the electrode assembly is accommodated in the shell. The battery comprises the battery monomer. The electric equipment comprises the battery. According to the electrode assembly, the battery monomer, the battery and the electric equipment, the condition of lithium precipitation caused by an overlarge edge gap between the two pole pieces can be improved.

Description

Technical Field

[0001] The utility model relates to the technical field of power batteries, in particular to an electrode assembly, a battery cell, a battery and an electrical equipment. Background Art

[0002] With the popularization and promotion of new energy vehicles, the charging and discharging performance, endurance and other aspects of new energy vehicles have attracted increasing attention and emphasis. A power battery is a rechargeable battery and the power source of a new energy vehicle, which is widely used in the field of new energy vehicles.

[0003] In a battery cell, generally, a positive electrode plate, a separator and a negative electrode plate are stacked, and then wound to form an electrode assembly. In order to improve the phenomenon of lithium deposition due to too little active material at the position of the electrode plate close to the winding center, a thickness thinning area is provided on the positive electrode plate and the negative electrode plate. At the same time, it is necessary to minimize the gap between the thickness thinning areas of the two electrode plates to improve the situation of lithium deposition caused by too large an edge gap between the two electrode plates. Therefore, how to reduce the gap between the thickness thinning areas of the two electrode plates is an urgent problem to be solved. Summary of the Utility Model

[0004] Based on this, in view of the problem of how to reduce the gap between the thickness thinning areas of the two electrode plates, it is necessary to provide an electrode assembly, a battery cell, a battery and an electrical equipment.

[0005] An electrode assembly includes a main electrode plate and a compensating member. The main electrode plate includes a first electrode plate and a second electrode plate. Thickness thinning areas are formed at the ends of the first electrode plate and the second electrode plate. The compensating member is arranged on the outer surface of the main electrode plate. Wherein, in the height direction of the main electrode plate, the compensating member includes an edge area and a body area adjacent to the edge area; the thickness of the edge area is greater than the thickness of the body area, and the edge area covers the thickness thinning area. In the above electrode assembly, by arranging the compensating member on the outer surface of the main electrode plate, the edge area of the compensating member is thickened, and the edge area of the compensating member covers the thickness thinning areas of the two electrode plates to reduce the gap between the thickness thinning areas of the two electrode plates and improve the situation of lithium deposition caused by too large an edge gap between the two electrode plates.

[0006] In some embodiments, the ratio range of the maximum thickness of the edge area to the maximum thickness of the body area is 10-1000. In this way, it can play a role in reducing the gap between the thickness thinning areas of the two electrode plates, and at the same time, the overall compensating member does not occupy too much space in the thickness direction.

[0007] In some embodiments, the ratio range of the maximum thickness of the edge area to the maximum thickness of the body area is 100-300. In this way, the gap between the thickness thinning areas of the two electrode plates can be minimized to the greatest extent, and the overall occupied space of the compensating member is optimized.

[0008] In some of these embodiments, the thickness of the edge region ranges from 0.1 µm to 300 µm. Thus, by defining the thickness range of the edge region, the gap in the thickness thinning interval of the two pole pieces can be reduced, and at the same time, the overall compensating member will not occupy too much space.

[0009] In some of these embodiments, the thickness of the body region ranges from 0.1 µm to 300 µm. Thus, by defining the thickness range of the body region, the overall compensating member will not occupy too much space.

[0010] In some of these embodiments, in the direction from the body region to the edge region, the thickness of the edge region gradually increases. Thus, the thickness of the edge region can be thickened, thereby effectively reducing the gap in the thickness thinning interval of the two pole pieces.

[0011] In some of these embodiments, along the thickness direction of the pole piece body, the edge region has two first surfaces and a second surface that are arranged opposite to each other. The first surface faces the pole piece body; the second surface is configured as an inclined surface, and the first surface is configured as a flat surface. Thus, the outer surface of the pole piece body is a flat structure. The first surface is configured as a flat surface to fit the outer surface of the substrate body, and the second surface is configured as an inclined surface to reduce the gap in the thickness thinning interval of the two pole pieces.

[0012] In some of these embodiments, in the direction from the body region to the edge region, the thickness of the body region is equal. Thus, the body region of the compensating member can be adapted to the flat coating region of the pole piece, thereby strengthening the bonding strength between the compensating member and the pole piece body.

[0013] In some of these embodiments, along the height direction of the pole piece body, the width of the edge region ranges from 0.5 mm to 10 mm. Thus, by defining the width range of the edge region, the overall compensating member will not occupy too much space and affect the insertion of the electrode assembly into the housing.

[0014] In some of these embodiments, along the height direction of the pole piece body, both the first pole piece and the second pole piece have two opposite ends; at least one end of the first pole piece and at least one end of the second pole piece are respectively formed with thickness thinning regions, and each thickness thinning region located at the same end is covered with a corresponding edge region. Thus, according to the actual situation, the setting position of the edge region can be flexibly adjusted, and the practicality of the compensating member is stronger.

[0015] In some of these embodiments, along the thickness direction of the pole piece body, the pole piece body has two opposite large surfaces, and at least one of the two large surfaces is provided with a compensating member. Thus, the gap in the thickness thinning interval of the two pole pieces can be reduced as much as possible.

[0016] In some of these embodiments, a coding region is provided on the compensating member. Thus, a code is provided on the coding region, which is convenient for subsequent tracing and maintenance of the electrode assembly.

[0017] In some of these embodiments, the electrode tab body further includes an insulating film disposed between the first electrode tab and the second electrode tab, and the first electrode tab, the insulating film, and the second electrode tab are wound to form the electrode tab body. In this way, the adjacent first electrode tab and the second electrode tab are isolated by the insulating film, preventing the two electrode tabs with opposite polarities from contacting and causing a short circuit.

[0018] A battery cell includes a housing, an end cap assembly, and the above-mentioned electrode assembly. The housing has an opening, the end cap assembly covers the opening, and the electrode assembly is accommodated in the housing. In the above-mentioned battery cell, by providing a compensating member on the outer surface of the electrode tab body, the edge region of the compensating member is thickened, and the edge region of the compensating member covers the thickness-thinned regions of the two electrode tabs, so as to reduce the gap between the thickness-thinned regions of the two electrode tabs and improve the situation of lithium deposition caused by too large an edge gap between the two electrode tabs.

[0019] A battery includes the above-mentioned battery cell. In the above-mentioned battery, the probability of lithium deposition in the battery cell is greatly reduced, improving the stability of battery use.

[0020] An electrical device includes the above-mentioned battery. In the above-mentioned electrical device, the battery has good stability in use, which is conducive to the continuous power supply of the electrical device. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 Schematic diagram of a vehicle in an embodiment provided by the present application.

[0022] Figure 2 Schematic diagram of a battery in an embodiment provided by the present application.

[0023] Figure 3 Explosion diagram of a battery cell in an embodiment provided by the present application.

[0024] Figure 4 Schematic diagram of an electrode assembly in an embodiment provided by the present application.

[0025] Figure 5 is Figure 4 The first cross-sectional view of the shown electrode assembly.

[0026] Figure 6 is Figure 4 The second cross-sectional view of the shown electrode assembly.

[0027] Figure 7 is Figure 6 The cross-sectional view of the compensating member in the shown electrode assembly.

[0028] Figure 8 is Figure 4 The front view of the compensating member in the shown electrode assembly.

[0029] Reference numerals:

[0030] 10. Vehicle; 11. Controller; 12. Motor; 20. Battery; 21. Box body; 21a. First part; 21b. Second part; 22. Battery cell; 23. Shell; 23a. Opening; 24. Electrode assembly; 25. End cover assembly; 100. Electrode tab body; 101. Thinned thickness area; 102. Large surface; 110. First electrode tab; 120. Second electrode tab; 130. Insulating film; 200. Compensation member; 201. Edge area; 201a. First surface; 201b. Second surface; 202. Body area; 203. Coding area. Detailed implementation manners

[0031] The embodiments of the technical solutions of the present application will be described in detail below with reference to the accompanying drawings. The following embodiments are only used to more clearly illustrate the technical solutions of the present application, and therefore are only examples and cannot be used to limit the protection scope of the present application.

[0032] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by those skilled in the technical field to which this application belongs; the terms used herein are only for the purpose of describing specific embodiments and are not intended to limit this application; the terms "including" and "having" and any variations thereof in the specification and claims of this application and the above drawings are intended to cover non-exclusive inclusion.

[0033] In the description of the embodiments of the present application, technical terms such as "first" and "second" are only used to distinguish different objects and cannot be understood as indicating or implying relative importance or implicitly indicating the quantity, specific order or primary-secondary relationship of the indicated technical features. In the description of the embodiments of the present application, "a plurality of" means more than two unless otherwise specifically defined.

[0034] Referring to "embodiments" herein means that specific features, structures or characteristics described in connection with the embodiments can be included in at least one embodiment of this application. The phrase appears in various places in the specification does not necessarily refer to the same embodiment, nor is it an independent or alternative embodiment mutually exclusive with other embodiments. Those skilled in the art explicitly and implicitly understand that the embodiments described herein can be combined with other embodiments.

[0035] In the description of the embodiments of the present application, the term "and / or" is only a description of the association relationship of associated objects, indicating that there can be three relationships. For example, A and / or B can mean: A exists alone, A and B exist simultaneously, and B exists alone. In addition, the character " / " in this article generally means that the associated objects before and after are in an "or" relationship.

[0036] In the description of the embodiments of the present application, the term "a plurality" refers to two or more (including two). Similarly, "multiple groups" refers to two or more groups (including two groups), and "multiple sheets" refers to two or more sheets (including two sheets).

[0037] In the description of the embodiments of the present application, for technical terms such as "center", "longitudinal", "lateral", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential", etc., the orientation or positional relationship indicated is based on the orientation or positional relationship shown in the drawings. It is only for the convenience of describing the embodiments of the present application and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation. Therefore, it should not be construed as a limitation on the embodiments of the present application.

[0038] In the description of the embodiments of the present application, unless otherwise clearly specified and limited, technical terms such as "installation", "connection", "connection", "fixation", etc. should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or integrated; it can also be a mechanical connection or an electrical connection; it can be directly connected or indirectly connected through an intermediate medium, and it can be the communication inside two elements or the interaction relationship between two elements. For those of ordinary skill in the art, the specific meanings of the above terms in the embodiments of the present application can be understood according to specific situations.

[0039] With the popularization and promotion of new energy vehicles, the charging and discharging performance, endurance ability, etc. of new energy vehicles have attracted increasing attention and emphasis. The power battery, which is a rechargeable battery, is the power source of new energy vehicles and is widely used in the field of new energy vehicles.

[0040] In a battery cell, generally, a positive electrode sheet, a separator, and a negative electrode sheet are stacked and then wound to form an electrode assembly. In order to improve the phenomenon of lithium deposition occurring due to too little active material in the position of the electrode sheet close to the winding center, a thickness-thinned area is provided on the positive electrode sheet and the negative electrode sheet. At the same time, it is necessary to minimize the gap between the thickness-thinned areas of the two electrode sheets to improve the situation of lithium deposition caused by too large an edge gap between the two electrode sheets. Therefore, how to reduce the gap between the thickness-thinned areas of the two electrode sheets is an urgent problem to be solved.

[0041] Based on the above considerations, through in-depth research, an electrode assembly, a battery cell, a battery, and an electrical device are designed. In the electrode assembly of the battery cell, by providing a compensating member on the outer surface of the electrode sheet body, the edge area of the compensating member is thickened, and the edge area of the compensating member covers the thickness-thinned areas of the two electrode sheets to reduce the gap between the thickness-thinned areas of the two electrode sheets and improve the situation of lithium deposition caused by too large an edge gap between the two electrode sheets.

[0042] Embodiments of the present application provide an electrical device powered by a battery. The electrical device can be, but is not limited to, a mobile phone, a tablet computer, a laptop computer, an electric toy, an electric tool, an electric vehicle, an electric car, a ship, a spacecraft, and the like. Among them, the electric toy can include a fixed or mobile electric toy, for example, a game console, an electric vehicle toy, an electric ship toy, an electric aircraft toy, and the like. The spacecraft can include an airplane, a rocket, a space shuttle, a spaceship, and the like.

[0043] For the convenience of description, the following embodiments will take a vehicle 10 in an embodiment of the present application as an example for illustration.

[0044] Please refer to Figure 1 , the vehicle 10 can be a fuel vehicle, a gas vehicle or a new energy vehicle. The new energy vehicle can be a pure electric vehicle, a hybrid vehicle or an extended-range vehicle, etc. A battery 20 is disposed inside the vehicle 10. The battery 20 can be disposed at the bottom, head or tail of the vehicle 10. The battery 20 can be used to supply power to the vehicle 10. For example, the battery 20 can be used as the operating power source of the vehicle 10. The vehicle 10 may further include a controller 11 and a motor 12. The controller 11 is used to control the battery 20 to supply power to the motor 12. For example, it is used for the working power requirements during the start, navigation and driving of the vehicle 10. In some other embodiments of the present application, the battery 20 can not only be used as the operating power source of the vehicle 10, but also be used as the driving power source of the vehicle 10, replacing or partially replacing fuel or natural gas to provide driving force for the vehicle 10.

[0045] Please refer to Figure 2 , the battery 20 includes a box body 21 and battery cells 22. The battery cells 22 are accommodated in the box body 21. Among them, the box body 21 is used to provide an accommodation space for the battery cells 22, and the box body 21 can adopt various structures. In some embodiments, the box body 21 can include a first part 21a and a second part 21b. The first part 21a and the second part 21b are covered with each other, and the first part 21a and the second part 21b jointly define an accommodation space for accommodating the battery cells 22. The second part 21b can be a hollow structure with one end open, and the first part 21a can be a plate-like structure. The first part 21a is covered on the open side of the second part 21b so that the first part 21a and the second part 21b jointly define the accommodation space; the first part 21a and the second part 21b can also be hollow structures with one side open, and the open side of the first part 21a is covered on the open side of the second part 21b. Of course, the box body 21 formed by the first part 21a and the second part 21b can be in various shapes, such as a cylinder, a cuboid, etc.

[0046] In the battery 20, there may be multiple battery cells 22. The multiple battery cells 22 can be connected in series, parallel, or in a combined series-parallel connection. A combined series-parallel connection means that there are both series and parallel connections among the multiple battery cells 22. The multiple battery cells 22 can be directly connected in series, parallel, or in a combined series-parallel connection and then the whole formed by the multiple battery cells 22 is accommodated in the box body 21. Of course, the battery 20 can also be such that multiple battery cells 22 are first connected in series, parallel, or in a combined series-parallel connection to form a battery module, and then multiple battery modules are connected in series, parallel, or in a combined series-parallel connection to form a whole and are accommodated in the box body 21.

[0047] Among them, each battery cell 22 can be a secondary battery or a primary battery; it can also be a lithium-sulfur battery, a sodium-ion battery, or a magnesium-ion battery, but is not limited thereto. The battery cell 22 can be in the shape of a cylinder, a flat body, a cuboid, or other shapes, etc. In some embodiments of the present application, the battery cell 22 can include a lithium-ion secondary battery, a lithium-ion primary battery, a lithium-sulfur battery, a sodium-lithium-ion battery, a sodium-ion battery, or a magnesium-ion battery, etc. The embodiments of the present application do not limit this. The battery cell 22 can be in the shape of a cylinder, a flat body, a cuboid, or other shapes, etc. The embodiments of the present application also do not limit this.

[0048] The following will describe any one of the battery cells 22 in detail. As Figure 3 shown, the battery cell 22 includes a housing 23, an electrode assembly 24, and an end cap assembly 25. The housing 23 is a hollow cuboid or cube, and one plane of the housing 23 has an opening 23a. This plane is configured to have no wall body so that the inside and outside of the housing 23 communicate. The end cap assembly 25 covers the opening 23a and is connected to the housing 23 to form a closed cavity for placing the electrode assembly 24. An electrolyte, such as an electrolytic solution, is filled in this closed cavity.

[0049] Please refer to Figures 4 to 6 , in one embodiment, the electrode assembly 24 includes a pole piece body 100 and a compensating member 200. The pole piece body 100 includes a first pole piece 110 and a second pole piece 120. Thickness-thinned areas 101 are formed at the ends of the first pole piece 110 and the second pole piece 120. The compensating member 200 is disposed on the outer surface of the pole piece body 100. Among them, with reference to Figure 7 , in the height direction of the pole piece body 100, the compensating member 200 includes an edge area 201 and a body area 202 adjacent to the edge area 201; the thickness of the edge area 201 is greater than the thickness of the body area 202, and the edge area 201 covers the thickness-thinned area 101.

[0050] It should be noted that the height direction of the pole piece body 100 is the Figure 7 Z direction shown. The edge area 201 covering the thickness-thinned area 101 can be understood as: in Figure 7In the Z direction shown, the edge region 201 completely covers the thickness-thinned region 101, or the edge region 201 at least partially covers the thickness-thinned region 101.

[0051] In an embodiment of the present application, the electrode sheet body 100 is mainly formed by winding a first electrode sheet 110 and a second electrode sheet 120, and an insulating film 130 is usually provided between the first electrode sheet 110 and the second electrode sheet 120. One of the first electrode sheet 110 and the second electrode sheet 120 is a positive electrode sheet, and the other of the first electrode sheet 110 and the second electrode sheet 120 is a negative electrode sheet. The portions of the first electrode sheet 110 and the second electrode sheet 120 having the active material constitute the main body portion of the battery cell assembly, and the portions of the first electrode sheet 110 and the second electrode sheet 120 without the active material respectively constitute the electrode tabs. The positive electrode tab and the negative electrode tab can be commonly located at one end of the main body portion or respectively located at both ends of the main body portion.

[0052] In an embodiment of the present application, the first electrode sheet 110 includes a substrate and an active material layer coated on the substrate. The thickness-thinned region 101 refers to a region where the thickness of the active material layer is smaller compared to the flat-coated region. The thickness-thinned region 101 is provided to relieve or reduce the shear stress received by the active material layer at the edge of the first electrode sheet 110. In the height direction of the electrode sheet body 100, the first electrode sheet 110 has two opposite ends, and the thickness-thinned region 101 is formed at at least one of the two ends of the first electrode sheet 110. The second electrode sheet 120 has the same specific structure as the first electrode sheet 110 except for the different polarities, and will not be described in detail here.

[0053] In an embodiment of the present application, the compensating member 200 is configured as a member on the outer surface of the electrode sheet body 100, and the compensating member 200 can be fixed to the outer surface of the electrode sheet body 100 by an adhesion method. Optionally, the compensating member 200 is an insulating adhesive.

[0054] In an embodiment of the present application, the number of the edge region 201 and the body region 202 is one. In Figure 7 the Z direction shown, the edge region 201 is the upper region of the compensating member 200, and the body region 202 is the lower region of the compensating member 200. In other embodiments, the number of the body region 202 is one, and the number of the edge regions 201 can also be two. In Figure 7 the Z direction shown, the two edge regions 201 are respectively located on the upper and lower sides of the compensating member 200.

[0055] For the above-mentioned electrode assembly 24, by providing the compensating member 200 on the outer surface of the electrode sheet body 100, the edge region 201 of the compensating member 200 is thickened, and the edge region 201 of the compensating member 200 covers the thickness-thinned regions 101 of the two electrode sheets, so as to reduce the gap between the thickness-thinned regions 101 of the two electrode sheets and improve the situation of lithium deposition caused by the excessive edge gap between the two electrode sheets.

[0056] According to some embodiments of the present application, please refer to Figure 7 that the ratio range of the maximum thickness of the edge region 201 to the maximum thickness of the body region 202 is 10 to 1000.

[0057] It should be noted that the maximum thickness W1 of the edge region 201 and the maximum thickness W2 of the body region 202 are the dimensions in the Figure 7 indicated X direction. The thickness design of the edge region 201 and the body region 202 needs to consider thickening the edge region 201 while the compensating member 200 does not occupy too much space.

[0058] Through the above settings, it can play a role in reducing the gap between the thickness thinning regions 101 of the two pole pieces, and at the same time, the overall compensating member 200 does not occupy too much space in the thickness direction.

[0059] According to some embodiments of the present application, please refer to Figure 7 that the ratio range of the maximum thickness of the edge region 201 to the maximum thickness of the body region 202 is 100 to 300.

[0060] Through the above settings, the gap between the thickness thinning regions 101 of the two pole pieces can be minimized to the greatest extent, and the overall occupied space of the compensating member 200 is optimized.

[0061] According to some embodiments of the present application, please refer to Figure 7 that the thickness range of the edge region 201 is 1 µm to 5000 µm.

[0062] Preferably, the thickness of the edge region 201 is 100 µm to 1000 µm.

[0063] Through the above settings, by limiting the thickness range of the edge region 201, the gap between the thickness thinning regions 101 of the two pole pieces can be reduced, and at the same time, the overall compensating member 200 does not occupy too much space.

[0064] According to some embodiments of the present application, please refer to Figure 7 that the thickness range of the body region 202 is 0.1 µm to 300 µm.

[0065] Preferably, the thickness of the body region 202 is 0.1 µm to 10 µm.

[0066] Through the above settings, by limiting the thickness range of the body region 202, the overall compensating member 200 does not occupy too much space.

[0067] According to some embodiments of the present application, please refer to Figure 7 that in the direction from the body region 202 to the edge region 201, the thickness of the edge region 201 gradually increases.

[0068] It can be understood that the direction from the main area 202 to the edge area 201 includes the direction along Figure 7 The Z direction (vertical upward direction) and the direction opposite to the Z direction (vertical downward direction) are shown.

[0069] For example, when the number of edge regions 201 and the number of main regions 202 are both one, the direction from the main region 202 to the edge region 201 refers to the vertically upward direction, that is, the thickness of the edge region 201 gradually increases from bottom to top; for another example, when the number of main regions 202 is one and the number of edge regions 201 is two, the direction from the main region 202 to the edge region 201 includes the vertically upward direction and the vertically downward direction, that is, the thickness of the edge region 201 located above gradually increases from bottom to top, and the thickness of the edge region 201 located below gradually increases from top to bottom.

[0070] In the embodiment of the present application, the thickness of the edge region 201 gradually increases, and the rate of increase may be linear or nonlinear.

[0071] Through the above arrangement, the thickness of the edge region 201 can be thickened, thereby effectively reducing the gap between the thinned regions 101 of the two pole pieces.

[0072] According to some embodiments of this application, please refer to Figure 7 Along the thickness direction of the pole piece body 100, the edge region 201 has two oppositely disposed first surfaces 201a and second surfaces 201b, the first surface 201a faces the pole piece body 100; the second surface 201b is constructed as an inclined surface, and the first surface 201a is constructed as a plane.

[0073] It should be noted that the thickness direction of the pole piece body 100 is Figure 7 X direction shown.

[0074] In the embodiment of the present application, the first surface 201a is the side of the edge area 201 facing the pole piece body 100, and the second surface 201b is the side of the edge area 201 away from the pole piece body 100. The first surface 201a is attached to the outer surface of the pole piece body 100, and the outer surface of the pole piece body 100 is a planar structure.

[0075] In the embodiment of the present application, the first surface 201a is configured as a plane, that is, coplanar or parallel to the plane where the YZ plane is located. The second surface 201b is configured as an inclined plane, that is, inclined relative to the plane where the YZ plane is located.

[0076] With the above settings, the outer surface of the electrode tab body 100 is a planar structure. The first surface 201a is configured as a plane to fit the outer surface of the substrate body, and the second surface 201b is configured as an inclined plane to reduce the gap between the thickness-thinned areas 101 of the two electrode tabs.

[0077] In some embodiments of the present application, please refer to Figure 7 , in the direction from the body area 202 to the edge area 201, the thickness of the body area 202 is equal.

[0078] It can be understood that in the direction from the body area 202 to the edge area 201, it includes, namely along Figure 7 the Z direction (vertically upward direction) shown, and the direction opposite to the Z direction (vertically downward direction).

[0079] In the embodiments of the present application, both the first electrode tab 110 and the second electrode tab 120 are provided with a flat coating area and a thickness-thinned area 101. The edge area 201 of the compensating member 200 covers the thickness-thinned area 101, and the body area 202 of the compensating member 200 covers the flat coating area.

[0080] For example, when the number of both the edge area 201 and the body area 202 is one, the direction from the body area 202 to the edge area 201 refers to the vertically upward direction, and the thickness of the body area 202 is equal; for another example, when the number of the body area 202 is one and the number of the edge area 201 is two, the direction from the body area 202 to the edge area 201 includes the vertically upward direction and the vertically downward direction, and the thickness of the body area 202 is equal.

[0081] With the above settings, the body area 202 of the compensating member 200 can be adapted to the flat coating area of the electrode tab, thereby enhancing the bonding strength between the compensating member 200 and the electrode tab body 100.

[0082] In some embodiments of the present application, please refer to Figure 7 , along the height direction of the electrode tab body 100, the width range of the edge area 201 is 0.5 mm to 10 mm.

[0083] Preferably, the width W3 of the edge area 201 is 2 mm to 5 mm.

[0084] With the above settings, by limiting the width range of the edge area 201, the whole compensating member 200 can be prevented from occupying too much space and affecting the insertion of the electrode assembly 24 into the housing.

[0085] In some embodiments of the present application, please refer to Figure 6, along the height direction of the electrode tab body 100, both the first electrode tab 110 and the second electrode tab 120 have two oppositely arranged ends; at least one end of the first electrode tab 110 and at least one end of the second electrode tab 120 are respectively formed with thickness-thinned areas 101, and each thickness-thinned area 101 located at the same end is covered with a corresponding edge area 201.

[0086] In an embodiment of the present application, in the height direction of the electrode tab body 100, the first electrode tab 110 has two oppositely arranged ends, the second electrode tab 120 has two oppositely arranged ends, and thickness-thinned areas 101 are respectively formed at at least one end of the first electrode tab 110 and at least one end of the second electrode tab 120.

[0087] For example, thickness-thinned areas 101 are respectively formed at one end of the first electrode tab 110 and one end of the second electrode tab 120. The two thickness-thinned areas 101 are located at the same end. Correspondingly, the number of both the edge area 201 and the body area 202 is one. The edge area 201 is located above the body area 202, and the edge area 201 covers the two thickness-thinned areas 101.

[0088] Also for example, thickness-thinned areas 101 are respectively formed at two ends of the first electrode tab 110 and two ends of the second electrode tab 120. Correspondingly, the number of the body area 202 is one and the number of the edge area 201 is two. One edge area 201 covers the two thickness-thinned areas 101 located at one end, and the other edge area 201 covers the two thickness-thinned areas 101 located at the other end.

[0089] Through the above settings, the setting position of the edge area 201 can be flexibly adjusted according to the actual situation, and the practicality of the compensating member 200 is stronger.

[0090] According to some embodiments of the present application, please refer to Figure 4 , along the thickness direction of the electrode tab body 100, the electrode tab body 100 has two oppositely arranged large surfaces 102, and at least one of the two large surfaces 102 is provided with a compensating member 200.

[0091] In an embodiment of the present application, at least one of the two large surfaces 102 is provided with a compensating member 200, that is, the compensating member 200 can be provided on one of the large surfaces 102, or the compensating member 200 can be provided on both large surfaces 102.

[0092] In an embodiment of the present application, the large surface 102 is rectangular. Correspondingly, the compensating member 200 is also rectangular to match the large surface 102. Alternatively, the compensating member 200 can also be circular, oval or other irregular shapes.

[0093] Through the above settings, the gap between the thickness-thinned areas 101 of the two electrode tabs can be reduced as much as possible.

[0094] According to some embodiments of the present application, please refer to Figure 8 , a coding area 203 is provided on the compensating member 200.

[0095] It should be noted that a code is provided on the coding area 203 to facilitate subsequent traceability and maintenance of the electrode assembly 24. Optionally, the code can be engraved on the coding area 203 by laser printing.

[0096] In the embodiments of the present application, the coding area 203 can be provided in the edge area 201 of the compensating member 200 or in the body area 202 of the compensating member 200. Here, the position of the coding area 203 is not specifically limited.

[0097] With the above arrangement, a code is provided on the coding area 203, which facilitates subsequent traceability and maintenance of the electrode assembly 24.

[0098] According to some embodiments of the present application, please refer to Figure 8 , the compensating member 200 is an insulating glue.

[0099] In the embodiments of the present application, the compensating member 200 has insulation properties, and the compensating member 200 can be any one of polyethylene terephthalate, polyphenylene sulfide, polycarbonate, and polypropylene.

[0100] With the above arrangement, the setting of the compensating member 200 can insulate the outer surface of the electrode tab body 100 from the outside.

[0101] According to some embodiments of the present application, please refer to Figure 6 , the electrode tab body 100 further includes an insulating film 130, the insulating film 130 is disposed between the first electrode tab 110 and the second electrode tab 120, and the first electrode tab 110, the insulating film 130, and the second electrode tab 120 are wound to form the electrode tab body 100.

[0102] In some embodiments of the present application, the insulating film 130 is a separator, and the separator is used to isolate the adjacent first electrode tab 110 and the second electrode tab 120 to prevent two electrode tabs with opposite polarities from contacting and causing a short circuit. The material of the separator can be one of an organic polymer insulating material, an inorganic insulating material, and a composite material. Preferably, the composite material is composed of an organic polymer insulating material and an inorganic insulating material.

[0103] With the above arrangement, the adjacent first electrode tab 110 and the second electrode tab 120 are isolated by the insulating film 130 to prevent two electrode tabs with opposite polarities from contacting and causing a short circuit.

[0104] Please refer to Figure 3, in one embodiment, the battery cell 22 includes a housing 23, an end cap assembly 25, and the above-mentioned electrode assembly 24. The housing 23 has an opening 23a, the end cap assembly 25 covers the opening 23a, and the electrode assembly 24 is accommodated in the housing 23.

[0105] In the embodiments of the present application, the electrode assembly 24 is a component in the battery cell 22 where an electrochemical reaction occurs. One or more electrode assemblies 24 may be included in the housing 23.

[0106] In some embodiments of the present application, the housing 23 is a component for cooperating with the end cap assembly 25 to form the internal environment of the battery cell 22. Among them, the formed internal environment can be used to accommodate the electrode assembly 24, the electrolyte, and other components. The housing 23 and the end cap assembly 25 may be independent components. An opening 23a may be provided on the housing 23, and the end cap assembly 25 covers the opening 23a at the opening 23a to form the internal environment of the battery cell 22; or the housing 23 and the end cap assembly 25 may be integrated. The housing 23 can be of various shapes and sizes, such as cuboid, cylindrical, hexagonal prism, etc.; the shape of the housing 23 can be determined according to the specific shape and size of the electrode assembly 24; the material of the housing 23 can be various, for example, copper, iron, aluminum, stainless steel, aluminum alloy, plastic, etc., and the embodiments of the present application do not make special restrictions on this.

[0107] For the above-mentioned battery cell 22, by providing a compensating member 200 on the outer surface of the electrode tab body 100, the edge region 201 of the compensating member 200 is thickened, and the edge region 201 of the compensating member 200 covers the thickness-thinned regions 101 of the two electrode tabs, so as to reduce the gap between the thickness-thinned regions 101 of the two electrode tabs and improve the situation of lithium deposition caused by too large an edge gap between the two electrode tabs.

[0108] Please refer to Figure 2 , in one embodiment, the battery 20 includes a box body 21 and the above-mentioned battery cell 22, and the battery cell 22 is disposed in the box body 21.

[0109] For the above-mentioned battery 20, the probability of lithium deposition in the battery cell 22 is greatly reduced, and the stability of the battery 20 during use is improved.

[0110] Please refer to Figure 1 , in one embodiment, an electrical device includes the above-mentioned battery 20, and the battery 20 is used to provide electrical energy.

[0111] For the above-mentioned electrical device, the battery 20 has good stability during use, which is beneficial to the continuous power supply of the electrical device.

[0112] According to some embodiments of the present application, refer to Figures 4 to 8, in one embodiment, the electrode assembly 24 includes a pole piece body 100 and a compensating member 200. The pole piece body 100 includes a first pole piece 110, a second pole piece 120, and an insulating film 130. The insulating film 130 is disposed between the first pole piece 110 and the second pole piece 120. The first pole piece 110, the insulating film 130, and the second pole piece 120 are wound to form the pole piece body 100. Along the thickness direction of the pole piece body 100, the pole piece body 100 has two relatively arranged large surfaces 102, and compensating members 200 are provided on both large surfaces 102. A coding area 203 is provided on the compensating member 200, and the compensating member 200 is an insulating adhesive.

[0113] Wherein, thickness-thinned areas 101 are formed at the ends of the first pole piece 110 and the second pole piece 120, and the compensating member 200 is disposed on the outer surface of the pole piece body 100; wherein, in the height direction of the pole piece body 100, the compensating member 200 includes an edge area 201 and a body area 202 adjacent to the edge area 201; the thickness of the edge area 201 is greater than the thickness of the body area 202, and the edge area 201 covers the thickness-thinned area 101. The ratio range of the thickness of the edge area 201 to the thickness of the body area 202 is 100-300, the thickness range of the edge area 201 is 0.1 µm-300 µm, and the thickness range of the body area 202 is 0.1 µm-300 µm. In the direction from the body area 202 to the edge area 201, the thickness of the edge area 201 gradually increases, and the thicknesses of the body area 202 are equal.

[0114] According to some embodiments of the present application, refer to Figure 3 , in one embodiment, the battery cell 22 includes a housing 23, an end cap assembly 25, and the above-mentioned electrode assembly 24. The housing 23 has an opening 23a, the end cap assembly 25 covers the opening 23a, and the electrode assembly 24 is accommodated in the housing 23.

[0115] According to some embodiments of the present application, refer to Figure 2 , in one embodiment, the battery 20 includes a box body 21 and the above-mentioned battery cell 22, and the battery cell 22 is disposed in the box body 21.

[0116] According to some embodiments of the present application, refer to Figure 1 , in one embodiment, the electrical device includes the above-mentioned battery 20, and the battery 20 is used to provide electrical energy.

[0117] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present application, rather than limiting them; 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 they can still modify the technical solutions described in the foregoing embodiments, or perform equivalent replacements for some or all of the technical features; and these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the various embodiments of the present application, and they should all be covered within the scope of the claims and the description of the present application. In particular, as long as there is no structural conflict, the technical features mentioned in each embodiment can be combined in any way. The present application is not limited to the specific embodiments disclosed in the text, but includes all technical solutions falling within the scope of the claims.

Claims

1. An electrode assembly (24), characterized in that: include: A pole piece body (100) comprises a first pole piece (110) and a second pole piece (120), wherein an end of the first pole piece (110) and an end of the second pole piece (120) are both formed with a thickness-reduced region (101); A compensation member (200) is arranged on the outer surface of the pole piece body (100); Wherein, in the height direction of the pole piece body (100), the compensation member (200) comprises an edge region (201) and a main body region (202) adjacent to the edge region (201); the thickness of the edge region (201) is greater than the thickness of the main body region (202), and the edge region (201) covers the thickness-reduced region (101).

2. The electrode assembly (24) according to claim 1, characterized in that The ratio of the maximum thickness of the edge region (201) to the maximum thickness of the main region (202) is in the range of 10 to 1000.

3. The electrode assembly (24) according to claim 1, characterized in that The ratio of the maximum thickness of the edge region (201) to the maximum thickness of the main region (202) is in the range of 100 to 300.

4. The electrode assembly (24) according to claim 1, characterized in that The thickness of the edge region (201) ranges from 1 µm to 5000 µm.

5. The electrode assembly (24) according to claim 1, characterized in that The thickness of the main region (202) ranges from 0.1µm to 300µm.

6. The electrode assembly (24) according to any one of claims 1 to 5, characterized in that: In a direction from the main body region (202) to the edge region (201), the thickness of the edge region (201) gradually increases.

7. The electrode assembly (24) according to claim 6, characterized in that Along the thickness direction of the pole piece body (100), the edge region (201) has two first surfaces (201a) and a second surface (201b) disposed opposite to each other, the first surface (201a) facing the pole piece body (100); the second surface (201b) is constructed as an inclined surface, and the first surface (201a) is constructed as a plane.

8. The electrode assembly (24) according to any one of claims 1 to 5, characterized in that: In a direction from the main region (202) to the edge region (201), the thickness of the main region (202) is equal.

9. The electrode assembly (24) according to any one of claims 1 to 5, characterized in that: Along the height direction of the pole piece body (100), the width of the edge area (201) ranges from 0.5 mm to 10 mm.

10. The electrode assembly (24) according to any one of claims 1 to 5, characterized in that: Along the height direction of the pole piece body (100), the first pole piece (110) and the second pole piece (120) each have two oppositely arranged ends; at least one end of the first pole piece (110) and at least one end of the second pole piece (120) are respectively formed with the thickness-reduced area (101), and each of the thickness-reduced areas (101) located at the same end is covered with the corresponding edge area (201).

11. The electrode assembly (24) according to any one of claims 1 to 5, characterized in that: Along the thickness direction of the pole piece body (100), the pole piece body (100) has two large surfaces (102) arranged opposite to each other, and at least one of the two large surfaces (102) is provided with the compensation piece (200).

12. The electrode assembly (24) according to any one of claims 1 to 5, characterized in that: The compensating piece (200) is provided with a coding area (203).

13. The electrode assembly (24) according to any one of claims 1 to 5, characterized in that: The pole piece body (100) further comprises an insulating film (130), wherein the insulating film (130) is arranged between the first pole piece (110) and the second pole piece (120), and the first pole piece (110), the insulating film (130) and the second pole piece (120) are wound to form the pole piece body (100).

14. A battery cell (22), characterized in that: include: A housing (23) having an opening (23a); An end cover assembly (25) covering the opening (23a); The electrode assembly (24) according to any one of claims 1 to 13, housed in the housing (23).

15. A battery (20), characterized in that: Comprising the battery cell (22) as claimed in claim 14.

16. An electrical equipment, characterized in that: Comprising the battery (20) as claimed in claim 15.

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