Battery

Abstract

To provide a battery advantageous in improving safety by improving impact resistance.SOLUTION: A battery includes an electrode assembly 10, a first insulating layer 20, a second insulating layer 30, and at least one first adhesive portion 40. The electrode assembly includes a first surface 101 and a second surface 103 opposite to the first surface. The first insulating layer is provided on the first surface. The second insulating layer is provided on the first surface and is spaced apart from the first insulating layer. The first adhesive portion is provided on the first surface and is located in a region between the first insulating layer and the second insulating layer.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to batteries. [Background technology]

[0002] As applications of consumer electronic products, electric vehicles, etc. mature, users are increasingly paying attention to the application risks of the entire device. For example, the requirements for impact resistance of electronic products are increasing. As an important component of electronic products, batteries also require impact resistance. When an electronic product is impacted, the electrode assembly housed in the battery case is likely to break the case, or the electrode assembly itself is broken by the impact, which affects the safety and service life of the battery. Summary of the Invention

[0003] In view of the above circumstances, it is necessary to provide a battery that is advantageous in improving safety by improving impact resistance.

[0004] The present invention provides a battery including an electrode assembly, a first insulating layer, a second insulating layer, and at least one first adhesive portion. The electrode assembly includes a first surface and a second surface opposite the first surface. The first insulating layer is disposed on the first surface. The second insulating layer is disposed on the first surface and spaced apart from the first insulating layer. The first adhesive portion is disposed on the first surface and is located in a region between the first insulating layer and the second insulating layer.

[0005] In one embodiment of the present invention, the battery includes two or more first adhesive parts, and the two or more first adhesive parts are distributed in a dot matrix.

[0006] In one embodiment of the present invention, the battery further includes a second adhesive portion provided on a side of the first insulating layer remote from the first surface.

[0007] In one aspect of the present invention, an area of ​​the second adhesive portion when orthogonally projected onto the first surface is smaller than an area of ​​the first insulating layer when orthogonally projected onto the first surface.

[0008] In one embodiment of the present invention, the battery includes at least two second adhesive parts, and the at least two second adhesive parts are distributed in a dot matrix.

[0009] In one aspect of the invention, the first insulating layer extends from the first surface to the second surface and the second insulating layer extends from the first surface to the second surface.

[0010] In one embodiment of the present invention, a metal portion is further provided at one end of the electrode assembly, and the first insulating layer and the second insulating layer are located at one end of the electrode assembly remote from the metal portion.

[0011] In one aspect of the present invention, an area of ​​an orthogonal projection of at least one first adhesive portion on the first surface is smaller than a total area of ​​an orthogonal projection of the first insulating layer and the second insulating layer on the first surface.

[0012] In one embodiment of the present invention, the area of ​​an orthogonal projection of at least one first adhesive portion on the first surface is smaller than the area of ​​an orthogonal projection of the first insulating layer on the first surface and smaller than the area of ​​an orthogonal projection of the second insulating layer on the first surface.

[0013] In one embodiment of the present invention, the distance from a portion of the area where the first surface and the first insulating layer contact each other to the second surface is a first distance, and the distance from the first adhesive portion to the second surface is a second distance, and the first distance is smaller than the second distance.

[0014] In one aspect of the invention, a distance from a portion of an area where the first surface and the second insulating layer contact each other to the second surface is a third distance, and the third distance is smaller than the second distance.

[0015] In one aspect of the invention, the first distance and the third distance are not equal.

[0016] In one embodiment of the present invention, the length of the first adhesive portion in the first direction is smaller than half the length of the first surface in the first direction.

[0017] In one aspect of the present invention, a first groove is provided on the first surface corresponding to the first adhesive portion, and the first adhesive portion is located within the first groove.

[0018] In one aspect of the present invention, a second groove is provided on the surface of the first insulating layer corresponding to the second adhesive portion, and the second adhesive portion is located within the second groove.

[0019] In one embodiment of the present invention, the battery further includes a third adhesive portion provided on a surface separate from the second surface of the first insulating layer, the third adhesive portion extending to an area of ​​the first surface where the first insulating layer is not provided.

[0020] In one embodiment of the present invention, the battery further includes a fourth adhesive portion, the fourth adhesive portion being provided on the first surface, the area of ​​the first surface where the fourth adhesive portion is provided being spaced apart from the area of ​​the first surface where the first insulating layer and the second insulating layer are provided and being spaced apart from the area of ​​the first surface between the first insulating layer and the second insulating layer, and the fourth adhesive portion not contacting either the first insulating layer or the second insulating layer.

[0021] In one embodiment of the present invention, the electrode assembly includes at least two fourth adhesive portions having different orthogonal projection shapes, and the fourth adhesive portions are distributed in a dot matrix.

[0022] In one embodiment of the present invention, the electrode assembly further includes a third insulating layer, the electrode assembly has a wound structure, and the third insulating layer is provided on the second surface and fixes an end of the outermost pole piece of the electrode assembly.

[0023] In one embodiment of the present invention, the battery further includes a case, which encases the electrode assembly, the first insulating layer and the second insulating layer, and is attached to the electrode assembly by a first adhesive.

[0024] In one embodiment of the present invention, the average orthogonal projection area on the first surface of the fourth adhesive portion is larger than the average orthogonal projection area on the first surface of the first adhesive portion.

[0025] In one embodiment of the present invention, the average orthogonal projection area on the first surface of the third adhesive portion is larger than the average orthogonal projection area on the first surface of the first adhesive portion and is also larger than the average orthogonal projection area on the first surface of the second adhesive portion.

[0026] In the battery of the present invention, a first insulating layer and a second insulating layer are provided on a surface of an electrode assembly, and a first adhesive is provided between the first insulating layer and the second insulating layer, and when the electrode assembly is packaged in a case, the first adhesive adheres the electrode assembly to the case.

[0027] When the battery is subjected to external force, it is advantageous to improve the safety of the battery and extend the service life of the battery. [Brief description of the drawings]

[0028] [Figure 1] FIG. 1 is a schematic diagram showing the configuration of a battery according to one embodiment of the present invention. [Diagram 2] FIG. 2 is a side view of a battery according to one embodiment of the present invention. [Diagram 3] FIG. 3 is a schematic diagram showing the configuration of a laminate according to one embodiment of the present invention. [Figure 4] FIG. 4 is a schematic diagram showing the configuration of a first conductive layer according to one embodiment of the present invention. [Diagram 5] FIG. 5 is a schematic diagram showing the configuration of the second conductive layer according to one embodiment of the present invention. [Figure 6] FIG. 6 is a schematic diagram of the configuration of an electrode assembly according to one embodiment of the present invention. [Figure 7] FIG. 7 is a schematic diagram of an electrode assembly according to one embodiment of the present invention. [Figure 8] FIG. 8 is a schematic diagram showing the configuration of a battery according to one embodiment of the present invention. [Figure 9A] FIG. 9A is a front view of a battery according to one embodiment of the present invention. [Figure 9B] FIG. 9B is a front view of a battery according to one embodiment of the present invention. [Figure 10]FIG. 10 is a schematic cross-sectional view taken along a first direction of a battery according to one embodiment of the present invention. [Figure 11] FIG. 11 is a schematic cross-sectional view taken along the second direction of a battery according to one embodiment of the present invention. [Figure 12] FIG. 12 is a schematic cross-sectional view taken along a first direction of a battery according to one embodiment of the present invention. [Figure 13] FIG. 13 is a schematic cross-sectional view taken along a first direction of a battery according to one embodiment of the present invention. [Figure 14] FIG. 14 is a schematic diagram showing the configuration of the first adhesive part or the fourth adhesive part according to one embodiment of the present invention. [Figure 15] FIG. 15 is a schematic diagram showing the configuration of the first adhesive part or the fourth adhesive part according to one embodiment of the present invention. [Figure 16] FIG. 16 is a schematic diagram showing the configuration of the first adhesive part or the fourth adhesive part according to one embodiment of the present invention. [Figure 17] FIG. 17 is a schematic diagram showing the configuration of the first adhesive part or the fourth adhesive part according to one embodiment of the present invention. [Figure 18] FIG. 18 is a schematic diagram showing the configuration of a battery according to one embodiment of the present invention. [Figure 19] FIG. 19 is a partially exploded schematic diagram of a battery according to one embodiment of the present invention. [Figure 20A] FIG. 20A is a schematic local cross-sectional view taken along a second direction of a battery according to one embodiment of the present invention. [Figure 20B] FIG. 20B is a schematic local cross-sectional view taken along the second direction of the battery according to one embodiment of the present invention. [Figure 21A] FIG. 21A is a schematic local cross-sectional view taken along a second direction of a battery according to one embodiment of the present invention. [Figure 21B] FIG. 21B is a schematic local cross-sectional view taken along the second direction of a battery according to one embodiment of the present invention. [Figure 22] FIG. 22 is a side view of a battery according to one embodiment of the present invention. [Diagram 23] FIG. 23 is a rear view of a battery according to one embodiment of the present invention. [Figure 24]FIG. 24 is a bottom view of a battery according to one embodiment of the present invention. [Diagram 25] FIG. 25 is a schematic diagram showing the configuration of a battery according to one embodiment of the present invention. [Figure 26] FIG. 26 is a schematic diagram showing the configuration of a battery according to one embodiment of the present invention. [Figure 27] FIG. 27 is a bottom view of a battery according to one embodiment of the present invention. [Figure 28] FIG. 28 is a schematic diagram showing a partial configuration of a battery according to Comparative Example 2 of the present invention. [Figure 29] FIG. 29 is a schematic diagram showing a partial configuration of a battery according to Comparative Example 3 of the present invention. [Diagram 30] FIG. 30 is a schematic diagram of a portion of the battery according to the first embodiment of the present invention. [Diagram 31] FIG. 31 is a schematic diagram showing a partial configuration of a battery according to Example 2 of the present invention. [Diagram 32] FIG. 32 is a schematic diagram showing a partial configuration of a battery according to Example 3 of the present invention. [Diagram 33] FIG. 33 is a schematic diagram showing a partial configuration of a battery according to Example 4 of the present invention. [Diagram 34] FIG. 34 is a schematic diagram showing the configuration of a battery according to one embodiment of the present invention. [Figure 35A] FIG. 35A is a schematic diagram of a battery according to one embodiment of the present invention. [Figure 35B] FIG. 35B is a schematic diagram of a battery according to one embodiment of the present invention. [Figure 36A] FIG. 36A is a schematic diagram of the configuration of a battery according to one embodiment of the present invention. [Figure 36B] FIG. 36B is a front view of a battery according to one embodiment of the present invention. [Figure 36C] FIG. 36C is a front view of a battery according to one embodiment of the present invention. [Figure 37] FIG. 37 is a side view of a battery according to one embodiment of the present invention. [Figure 38] FIG. 38 is a schematic cross-sectional view taken along a first direction of a battery according to one embodiment of the present invention. [Figure 39]FIG. 39 is a schematic cross-sectional view taken along the second direction of a battery according to one embodiment of the present invention. [Diagram 40] FIG. 40 is a schematic cross-sectional view taken along a first direction of a battery according to one embodiment of the present invention. [Diagram 41] FIG. 41 is a schematic cross-sectional view taken along a first direction of a battery according to one embodiment of the present invention. [Diagram 42] FIG. 42 is a partially exploded schematic diagram of a battery according to one embodiment of the present invention. [Diagram 43] FIG. 43 is a schematic local cross-sectional view taken along the second direction of a battery according to one embodiment of the present invention. [Diagram 44] FIG. 44 is a schematic local cross-sectional view taken along the second direction of a battery according to one embodiment of the present invention. [Diagram 45] FIG. 45 is a schematic local cross-sectional view taken along the second direction of a battery according to one embodiment of the present invention. [Figure 46] FIG. 46 is a schematic local cross-sectional view taken along the second direction of a battery according to one embodiment of the present invention. [Figure 47] FIG. 47 is a side view of a battery according to one embodiment of the present invention. [Figure 48] FIG. 48 is a schematic diagram of a battery according to one embodiment of the present invention. [Figure 49] FIG. 49 is a schematic diagram showing the configuration of a battery according to one embodiment of the present invention. [Figure 50] FIG. 50 is a bottom view of a battery according to one embodiment of the present invention. [Figure 51] FIG. 51 is a bottom view of a battery according to one embodiment of the present invention. [Figure 52] FIG. 52 is a schematic diagram of the configuration of a battery according to one embodiment of the present invention. [Diagram 53] FIG. 53 is a schematic diagram of the configuration of a battery according to one embodiment of the present invention. [Figure 54A] FIG. 54A is a schematic diagram of a battery according to one embodiment of the present invention. [Figure 54B] FIG. 54B is a schematic diagram of a battery according to one embodiment of the present invention. [Figure 55]FIG. 55 is a schematic diagram of the configuration of a battery according to one embodiment of the present invention. [Figure 56] FIG. 56 is a schematic diagram of the configuration of a battery according to one embodiment of the present invention. [Figure 57] FIG. 57 is a schematic diagram of the configuration of a battery according to one embodiment of the present invention. [Figure 58] FIG. 58 is a schematic diagram of a battery according to one embodiment of the present invention. [Figure 59] FIG. 59 is a schematic diagram of a battery according to one embodiment of the present invention. [Figure 60] FIG. 60 is a schematic diagram of the configuration of a battery according to one embodiment of the present invention. [Figure 61] FIG. 61 is a schematic diagram of the configuration of a battery according to one embodiment of the present invention. [Figure 62] FIG. 62 is a schematic diagram of the configuration of a battery according to one embodiment of the present invention. [Figure 63] FIG. 63 is a schematic diagram of the configuration of a battery according to one embodiment of the present invention. [Figure 64] FIG. 64 is a locally enlarged schematic diagram of a battery according to one embodiment of the present invention. [Figure 65A] FIG. 65A is a schematic cross-sectional view of a battery according to one embodiment of the present invention taken along the direction KK in FIG. 62. [Figure 65B] FIG. 65B is a cross-sectional schematic diagram of a battery according to one embodiment of the present invention. [Figure 66] FIG. 66 is a locally enlarged schematic diagram of a battery according to one embodiment of the present invention. [Figure 67] FIG. 67 is a locally enlarged schematic diagram of a battery according to one embodiment of the present invention.

[0029] The present invention will be further described below in conjunction with the detailed description and the above drawings. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0030] The technical solutions in the embodiments of the present invention will be described below in detail and clearly. Obviously, the described embodiments are only some of the embodiments of the present invention, and not all of the embodiments. Unless otherwise defined, all technical and scientific terms used in the present specification have the same meaning as commonly understood by those skilled in the art in the technical field to which the present invention belongs. The terms used in the specification of the present invention are only for describing specific embodiments, and are not intended to limit the present invention.

[0031] Hereinafter, the embodiments of the present invention will be described in detail. However, the present invention can be embodied in many different forms and should not be construed as being limited to the embodiments set forth herein. Rather, these embodiments are provided to provide a thorough and detailed description of the contents of the present invention to those skilled in the art.

[0032] It should be noted that in the drawings, the sizes or thicknesses of various assemblies, layers have been exaggerated for convenience and clarity. Like numerals refer to like elements throughout. As used herein, the term "and / or" includes any and all combinations of one or more of the associated listed items. It should be understood that when element A is referred to as "connecting" element B, element A may be directly connected to element B, or there may be an intermediate element C such that elements A and B are indirectly connected to each other.

[0033] Furthermore, the terms "can" or "may" when used in describing embodiments of the present invention may refer to "one or more embodiments of the present invention."

[0034] The terminology used herein is for the purpose of describing a particular embodiment and is not intended to limit the present invention. As used herein, the singular form includes the plural form unless otherwise specified in the specification. It should be further understood that the term "comprises" as used herein refers to the presence of the recited features, values, steps, operations, elements, and / or components, but does not exclude the presence or addition of one or more other features, values, steps, operations, elements, components, and / or combinations thereof.

[0035] Spatial terms, such as "above" are used herein for convenience to describe the relationship of one element or feature to another element(s) or feature(s) shown in the figures. It should be understood that spatial terms are intended to encompass different orientations of a device or apparatus in use or operation in addition to the orientation shown in the figures. For example, an element described as "above" or "on" another element or feature would be oriented "below" or "below" the other element or feature if the device in the figures were inverted. Thus, the exemplary term "above" can include an orientation of above and below. It should be understood that, although terms such as first, second, third, etc. may be used herein to describe various elements, components, regions, layers, and / or portions, these elements, components, regions, layers, and / or portions should not be limited by these terms. These terms are used to distinguish one element, component, region, layer, or portion from another element, component, region, layer, or portion. Thus, a first element, component, region, layer, or portion described below can be referred to as a second element, component, region, layer, or portion without departing from the teachings of the exemplary embodiments. In the present invention, the first direction can be any direction in the plane in which the first surface lies.

[0036] Hereinafter, several embodiments of the present invention will be described in detail. The following examples and features in the examples may be combined with each other if they are not mutually inconsistent.

[0037] Referring to FIG. 1, a battery 100 includes an electrode assembly 10 , a first insulating layer 20 , a second insulating layer 30 , and a first adhesive portion 40 .

[0038] Referring to FIG. 1, the electrode assembly 10 includes a first surface 101, a second surface 103 opposite the first surface 101, and a connection region 105 connecting the first surface 101 and the second surface 103.

[0039] 1, the electrode assembly 10 includes a pole piece 11 and a separator (not shown), and has a wound structure formed by winding the pole piece 11 and the separator. The first surface 101, the second surface 103, and the connection region 105 form part of the outer surface of the electrode assembly 10.

[0040] For example, the electrode assembly 10 shown in Fig. 1 has a structure formed by being wound several times, where the electrode assembly 10 has a plurality of bent portions in one direction, i.e., the X direction in the figure, and the plurality of bent portions are distributed on either side of the center of the battery 100 along the X direction, i.e., on the left and right sides in Fig. 1. Here, the connection point between one outer flat surface of the electrode assembly 10 and one end closest to the center of the battery 100 in the bent portion located at the outermost position on the left side of the center of the battery 100 is the first end 101A, and the connection point between the outer flat surface of the electrode assembly 10 and one end closest to the center of the battery 100 in the bent portion located at the outermost position on the right side of the center of the battery 100 is the second end 101B.

[0041] In this embodiment, the first surface 101 is, for example, an area surrounded by a first end 101A, a second end 101B, and two ends along the Y direction of the electrode assembly 10, i.e., a first side 16 and a second side 18, when viewed from the Z direction shown in FIG.

[0042] For example, for a stacked electrode assembly 10 in which pole pieces 11 and separators are stacked along the Z direction, the electrode assembly 10 includes four edges perpendicular to the Z direction, and the area surrounded by the four edges is the second surface 103.

[0043] The electrode assembly 10 will now be further described by way of an example.

[0044] Referring to FIG. 3, the battery assembly 10 may include a first conductive layer 10A, a first separator layer 10B, a second conductive layer 10C, and a second separator layer 10D. Here, the first separator layer 10B is formed on a surface 10a of the first conductive layer 10A. The second conductive layer 10C is formed on a surface 10b of the first separator layer 10B that is separated from the first conductive layer 10A. The second separator layer 10D is formed on a surface 10c of the second conductive layer 10C that is separated from the first separator layer 10B. This forms a laminate 10E, and the electrode assembly 10 is formed based on this laminate 10E.

[0045] 3 and 4, the first conductive layer 10A may have, for example, a rectangular shape when viewed from a direction perpendicular to the surface 10a. The first conductive layer 10A may be formed, for example, by stacking a current collector 10AA and an active material layer 10AB on each other. The current collector 10AA may include, but is not limited to, at least one of conductive metal thin plates such as aluminum mesh and aluminum foil. The active material layer 10AB may include, but is not limited to, at least one of lithium cobalt oxide, lithium nickel cobalt manganese oxide, lithium nickel cobalt aluminum oxide, lithium manganese oxide, lithium nickel oxide, lithium manganese iron phosphate, lithium vanadium phosphate, lithium oxovanadyl phosphate, lithium iron phosphate, lithium titanate, and lithium-rich manganese-based materials. The first conductive layer 10A may be, for example, a positive electrode piece when constructing the electrode assembly 10 of the battery 100.

[0046] 3, the first separator layer 10B may have, for example, a rectangular shape when viewed in a direction perpendicular to the surface 10b. The first separator layer 10B may include, for example, but is not limited to, at least one or more of polyethylene, polypropylene, polyethylene terephthalate, polyimide, and aramid. The first separator layer 10B may be used as a separator when forming the electrode assembly 10 of the battery 100, for example.

[0047] 3 and 5, the second conductive layer 10C may have, for example, a rectangular shape when viewed from a direction perpendicular to the surface 10c. The second conductive layer 10C may be formed, for example, by stacking a current collector 10CA and an active material layer 10CB on each other. The current collector 10CA may include, for example, at least one or two of conductive metal thin plates such as nickel foil and copper foil, but is not limited thereto. The active material layer 10CB may include, for example, at least one or more of graphite, soft carbon, hard carbon, graphene, mesocarbon microbeads, silicon-based materials, tin-based materials, lithium titanate, or other metals capable of forming an alloy with lithium, but is not limited thereto. The second conductive layer 10C may be, for example, a negative electrode piece when constructing the electrode assembly 10 of the battery 100.

[0048] When viewed from a direction perpendicular to the surface 10b, the second separator layer 10D may have, for example, a rectangular shape. The second separator layer 10D may include, for example, at least one or more of polyethylene, polypropylene, polyethylene terephthalate, polyimide, and aramid, but is not limited thereto. The second separator layer 10D may be used as a separator when forming the electrode assembly 10 of the battery 100, for example.

[0049] 6, the electrode assembly 10 can be formed, for example, by winding up a laminate 10Ea formed by stacking a plurality of laminates 10E. Alternatively, for example, referring to FIG. 7, the electrode assembly 10 can be formed by directly stacking a plurality of laminates 10E along the Z direction.

[0050] In this embodiment, the outer surface of the electrode assembly 10 includes a first surface 101 and a second surface 103 spaced apart from the first surface 101. The outer surface of the electrode assembly 10 further includes a connection region 105 in a third direction Z perpendicular to the first surface 101.

[0051] In this embodiment, the second surface 103 is, for example, an area corresponding to an area surrounded by the first end 101A, the second end 101B, and the two ends along the Y direction of the electrode assembly 10, i.e., the first side 16 and the second side 18, in a plane opposite to the first surface 101 of the electrode assembly 10, when viewed from the Z direction shown in FIG. 1.

[0052] 1 and 8, the connection region 105 includes a first portion 106 and a second portion 107 opposite to the first portion 106. The electrode assembly 10 may further include a metal portion 15 provided on the first portion 106. One end of the metal portion 15 is connected to the pole piece 11, and the other end can be connected to another electronic element to realize electrical conduction between the electrode assembly 10 and another electronic element.

[0053] The first insulating layer 20 and the second insulating layer 30 are both provided on the first surface 101, and the first insulating layer 20 and the second insulating layer 30 are provided along the first direction X with a gap therebetween.

[0054] In this embodiment, the first insulating layer 20 may be, for example, rectangular when viewed from the third direction Z. The first insulating layer 20 may include, for example, at least one of polyimide, polyvinyl chloride, polyethylene, and polypropylene, but is not limited thereto. The second insulating layer 30 may be, for example, rectangular when viewed from the third direction Z. The second insulating layer 30 may include, for example, at least one of polyimide, polyvinyl chloride, polyethylene, and polypropylene, but is not limited thereto.

[0055] The first surface 101 and the second portion 107 meet at a first side 16. In some embodiments, the first direction X is the direction in which the first side 16 is located. When viewed from a third direction Z, the first insulating layer 20 and the second insulating layer 30 each extend along the first surface 101 from the first side 16 towards the first portion 106, but do not reach the first portion 106.

[0056] The length L1 of the first insulating layer 20 extending from the first side 16 toward the first portion 106 and the length L2 of the second insulating layer 30 extending from the first side 16 toward the first portion 106 are not particularly limited when the first insulating layer 20 does not reach the first portion 106 and when the second insulating layer 30 does not reach the first portion 106. In this embodiment, the length L1 of the first insulating layer 20 extending from the first side 16 toward the first portion 106 is equal to the length L2 of the second insulating layer 30 extending from the first side 16 toward the first portion 106. Here, the above length direction is defined as the second direction Y.

[0057] The first insulating layer 20 and the second insulating layer 30 may each include an adhesive layer and a substrate, which are laminated together. Here, the adhesive layer bonds the substrate and the electrode assembly 10. The adhesive layer may include, but is not limited to, at least one of natural rubber, synthetic rubber, acrylate, silica gel, and ethylene-vinyl acetate. The substrate may include, but is not limited to, at least one of polyethylene, polypropylene, Teflon, polyvinyl chloride, polyimide, and nonwoven fabric.

[0058] 1, 2 and 9A, when viewed from a third direction Z perpendicular to the first surface 101, the first adhesive portion 40 is provided on the first surface 101 and is located in a region 101a between the first insulating layer 20 and the second insulating layer 30. In the second direction Y, the first adhesive portion 40 does not exceed the first insulating layer 20 and the second insulating layer 30. In some embodiments, the length of the region 101a in the first direction X can be less than half the length of the first surface 101 in the first direction X.

[0059] In some embodiments, the area of ​​the orthogonal projection of the first adhesive portion 40 on the first surface 101, in other words, the area of ​​the projection of the first adhesive portion 40 on the first surface 101 along the third direction Z perpendicular to the first surface 101, can be smaller than the total area of ​​the orthogonal projections of the first insulating layer 20 and the second insulating layer 30 on the first surface 101. Furthermore, in some embodiments, the area of ​​the orthogonal projection of the first adhesive portion 40 on the first surface 101 can be smaller than the area of ​​the orthogonal projection of the first insulating layer 20 on the first surface 101, and at the same time, can be smaller than the area of ​​the orthogonal projection of the second insulating layer 30 on the first surface 101. The first adhesive portion 40 may include at least one polymer selected from the group consisting of, for example, cellulose, polyvinylidene fluoride-co-hexafluoropropylene, polyvinylidene fluoride-co-trichloroethylene, polymethyl methacrylate, polybutyl acrylate, polyacrylonitrile, polyvinylpyrrolidone, polyvinyl acetate, polyethylene-co-vinyl acetate, polyethylene oxide, polyarylate, cellulose acetate, cellulose acetate butyrate, cellulose acetate propionate, cyanoethyl pullulan, cyanoethyl polyvinyl alcohol, cyanoethyl cellulose, cyanoethyl sucrose, pullulan, carboxymethyl cellulose, and polypropylene-maleic anhydride, or a mixture of any combination of the above polymers, but is not limited to these.

[0060] 10, the first distance H1 from at least a part of the area where the first surface 101 overlaps with the first insulating layer 20 to the second surface 103 is smaller than the second distance H2 from the first adhesive portion 40 to the second surface 103. In order to ensure that the first distance H1 is smaller than the second distance H2, the distances from different positions in at least a part of the area where the first surface 101 overlaps with the first insulating layer 20 to the second surface 103 may be different. Further, referring to FIGS. 1, 9A, and 10 in combination, here, the first distance H1 from at least a part of the area where the first side 16 overlaps with the first insulating layer 20, i.e., the end of the first surface 101 corresponding to the first insulating layer 20, to the second surface 103 is smaller than the second distance H2 from the first adhesive portion 40 to the second surface 103.

[0061] 11 , a first recess 120 extending from the first side 16 toward the first portion 106 is provided in the first surface 101. At least a portion of the first insulating layer 20 away from the first portion 106 is provided in the first recess 120. In this embodiment, the first recess 120 may be an inclined groove, and the depth of the first recess 120 gradually decreases from the first side 16 toward the first portion 106 along the second direction Y. A portion of the first insulating layer 20 close to the first portion 106 may be located outside the first recess 120.

[0062] 1, 9A, and 10 in combination, a third distance H3 from at least a portion of the region where the first surface 101 overlaps with the second insulating layer 30 to the second surface 103 is smaller than the second distance H2. In order to ensure that the third distance H3 is smaller than the second distance H2, the distances from different positions in at least a portion of the region where the first surface 101 overlaps with the second insulating layer 30 to the second surface 103 may be different. Furthermore, here, the third distance H3 from at least a portion of the region where the first side 16 overlaps with the second insulating layer 30, i.e., the end of the first surface 101 corresponding to the second insulating layer 30, to the second surface 103 is smaller than the second distance H2.

[0063] 11 , a second recess 130 is provided in the first surface 101, extending from the first side 16 toward the first portion 106. At least a portion of the second insulating layer 30 away from the first portion 106 is provided in the second recess 130. In this embodiment, the second recess 130 may be an inclined groove, and the depth of the second recess 130 gradually decreases from the first side 16 toward the first portion 106 along the second direction Y. A portion of the second insulating layer 30 close to the first portion 106 may be located outside the second recess 130.

[0064] In some embodiments, referring to FIG. 12, the first distance H1 and the third distance H3 may not be equal.

[0065] 13 , the first surface 101 may be provided with first grooves 140. The first adhesive portions 40 are located in the first grooves 140. In this embodiment, the number of the first adhesive portions 40 is multiple, the number of the first grooves 140 is multiple, and each first adhesive portion 40 is located in one first groove 140.

[0066] When viewed from the third direction Z, the shape and size of the first adhesive portion 40 are not limited, and may be a circle (see FIG. 9A), a rectangle (see FIG. 14 and FIG. 15), a strip (see FIG. 16), other regular or irregular shapes, or a combination thereof. The number of the first adhesive portions 40 may be one or more according to actual needs. When the number of the first adhesive portions 40 is more than one, the first adhesive portions 40 are provided at intervals (for example, distributed in a dot matrix). When viewed from the third direction Z, the battery 100 may include at least two first adhesive portions 40 with different shapes (see FIG. 17) or at least two first adhesive portions 40 with different sizes (see FIG. 9B). In some embodiments, referring to FIG. 9A, when viewed from the third direction Z, the shapes of all the first adhesive portions 40 may be the same.

[0067] 18 and 19, the battery 100 may further include a case 80. The case 80 may include, but is not limited to, one or more of an aluminum laminate film, a heat shrinkable film, an aluminum case, and a steel case. The case 80 encases the electrode assembly 10, the first insulating layer 20, and the second insulating layer 30, and is attached to the electrode assembly 10 by a first adhesive portion 40 (see FIGS. 20A and 20B at the same time). In some embodiments, as shown in FIG. 20B, the case 80 may be provided with a groove 140'. A portion of the first adhesive portion 40 is located in the groove 140'. The first adhesive portion 40 is provided in the region 101a between the first insulating layer 20 and the second insulating layer 30, so that the region in the battery 100 where the first insulating layer 20 and the second insulating layer 30 are provided and the region in the battery corresponding to the region 101a can be more uniformly compressed in the horizontal direction, i.e., the first direction X and the second direction Y, during the formation process, which is advantageous in reducing the degree of deformation during the use of the battery 100. The first adhesive portion 40 is provided between the first insulating layer 20 and the second insulating layer 30, so that the adhesive force between the electrode assembly 10 and the case 80 can be improved, and therefore, when the battery 100 is subjected to an external force, the relative displacement between the electrode assembly 10 and the case 80 can be suppressed, and further, the possibility that the battery 100 is damaged by the external force can be reduced, and the service life of the battery 100 can be extended. At the same time, the first adhesive portion 40 adheres the case 80 and the electrode assembly 10, which also contributes to suppressing deformation of the electrode assembly 10. In addition, the shape of the first adhesive portion 40 after adhering to the case 80 may change. When the number of the first adhesive portions 40 is plural, the first adhesive portions 40 may be provided with a gap between them after adhering to the case 80, or adjacent first adhesive portions 40 may be connected to each other (see FIG. 16). When the first adhesive portions 40 are distributed in a dot matrix, the first adhesive portions 40 can be installed more flexibly and the positions at which the first adhesive portions 40 are provided can be more precise, and at the same time, the thickness of the first adhesive portions 40 after adhering to the case 80 can be more consistent.

[0068] 1, 2, 9A, and 10, the battery 100 may further include a second adhesive portion 50 provided on a surface 21 separated from the second surface 103 of the first insulating layer 20. The area of ​​the orthogonal projection of the second adhesive portion 50 on the first surface 101 is smaller than the area of ​​the orthogonal projection of the second adhesive portion 50 on the first surface 101 of the first insulating layer 20. The second adhesive portion 50 may be provided on a surface 31 separated from the second surface 103 of the second insulating layer 30. In this case, the area of ​​the orthogonal projection of the second adhesive portion 50 on the first surface 101 is smaller than the area of ​​the orthogonal projection of the second adhesive portion 50 on the first surface 101 of the second insulating layer 30.

[0069] The second adhesive portion 50 may include, for example, but is not limited to, at least one polymer selected from the group consisting of cellulose, polyvinylidene fluoride-co-hexafluoropropylene, polyvinylidene fluoride-co-trichloroethylene, polymethyl methacrylate, polybutyl acrylate, polyacrylonitrile, polyvinylpyrrolidone, polyvinyl acetate, polyethylene-co-vinyl acetate, polyethylene oxide, polyarylate, cellulose acetate, cellulose acetate butyrate, cellulose acetate propionate, cyanoethyl pullulan, cyanoethyl polyvinyl alcohol, cyanoethyl cellulose, cyanoethyl sucrose, pullulan, carboxymethyl cellulose, and polypropylene-maleic anhydride, or a mixture of any combination of the above polymers.

[0070] When viewed from the third direction Z, the shape of the second adhesive portion 50 is not limited and may be circular, rectangular, strip-like, other regular or irregular shapes, or a combination thereof. The number of the second adhesive portions 50 may be one or more according to actual needs. When the number of the second adhesive portions 50 is more than one, the second adhesive portions 50 are provided at intervals (e.g., distributed in a dot matrix). When viewed from the third direction Z, the battery 100 may include at least two second adhesive portions 50 with different shapes. In some embodiments, when viewed from the third direction Z, the shapes of all the second adhesive portions 50 may be the same.

[0071] 13, in some embodiments, a second groove 150 is provided in a surface of the first insulating layer 20 opposite the second surface 103. The second adhesive portion 50 is located in the second groove 150.

[0072] 18, 21A and 21B, the case 80 is adhered to the first insulating layer 20 by the second adhesive part 50, which is advantageous for stability between the electrode assembly 10 and the case 80. Furthermore, the case 80 is adhered to the second insulating layer 30 by the second adhesive part 50, which is advantageous for stability between the electrode assembly 10 and the case 80. The case 80 can further be adhered to the first insulating layer 20 and the second insulating layer 30 by the second adhesive part 50. By using the second adhesive part 50, it is possible to avoid directly adhering the case 80 to the electrode assembly 10. During the process of dropping the battery 100, it is not the case 80 and the electrode assembly 10 that are bonded by the second adhesive portion 50, but rather the case 80 and the first insulating layer 20, or the case 80 and the second insulating layer 30. Furthermore, the area of ​​the orthogonal projection of the second adhesive portion 50 on the first surface 101 is smaller than the area of ​​the orthogonal projection of the first insulating layer 20 or the second insulating layer 30 on the first surface 101 to which the second adhesive portion 50 is bonded, that is, the area of ​​the first insulating layer 20 or the second insulating layer 30 in contact with the electrode assembly 10 is large. Therefore, the case 80 distributes the tensile force applied to the electrode assembly 10 by the second adhesive portion 50, thereby reducing the probability of damage caused by pulling the electrode assembly 10, and thereby reducing the risk of short-circuiting the positive and negative electrodes. When the number of the second adhesive parts 50 is plural, the second adhesive parts 50 may be spaced apart from each other after the case 80 is bonded, or adjacent second adhesive parts 50 may be connected to each other. When the second adhesive parts 50 are distributed in a dot matrix, the installation of the second adhesive parts 50 is more flexible, and the position where the second adhesive parts 50 are provided can be more precise, and at the same time, the thickness of the second adhesive parts 50 after bonding to the case 80 can be more consistent. In some embodiments, as shown in FIG. 21B, the case 80 may further be provided with a groove 150'. A part of the second adhesive part 50 is located in the groove 150'.

[0073] 1, 2, and 9A, the battery 100 may further include a third adhesive portion 60. The third adhesive portion 60 is provided on a surface 21 separate from the second surface 103 of the first insulating layer 20, and extends to the first surface 101 across the boundary between the first insulating layer 20 and the first surface 101.

[0074] The third adhesive portion 60 may include, for example, but is not limited to, at least one polymer selected from the group consisting of cellulose, polyvinylidene fluoride-co-hexafluoropropylene, polyvinylidene fluoride-co-trichloroethylene, polymethyl methacrylate, polybutyl acrylate, polyacrylonitrile, polyvinylpyrrolidone, polyvinyl acetate, polyethylene-co-vinyl acetate, polyethylene oxide, polyarylate, cellulose acetate, cellulose acetate butyrate, cellulose acetate propionate, cyanoethyl pullulan, cyanoethyl polyvinyl alcohol, cyanoethyl cellulose, cyanoethyl sucrose, pullulan, carboxymethyl cellulose, and polypropylene-maleic anhydride, or a mixture composed of any combination of the above polymers.

[0075] 18, 21A and 21B, the third adhesive portion 60 is attached to the case 80. The case 80 can be adhered to the first insulating layer 20 by the third adhesive portion 60. The case 80 can be further adhered to the second insulating layer 30 by the third adhesive portion 60. The case 80 can be further adhered to the first insulating layer 20 and the second insulating layer 30 simultaneously by the third adhesive portion 60. In some embodiments, as shown in FIG. 21B, a groove 160' can be provided in the case 80. A portion of the third adhesive portion 60 is located in the groove 160'.

[0076] 1, 2, 9A, 21A, and 21B, the battery 100 may further include a fourth adhesive portion 70 provided in a region 101b of the first surface 101. The region 101b is provided at a distance from the region of the first surface 101 where the first insulating layer 20 and the second insulating layer 30 are provided, and is provided at a distance from the region 101a of the first surface 101, and the fourth adhesive portion 70 does not contact the first insulating layer 20 and the second insulating layer 30.

[0077] 9A, the region 101b includes a first block 101b1 and a second block 101b2. The first block 101b1 is separated from the region 101a in the second direction Y. The second block 101b2 is located on a side of the first insulating layer 20 separated from the second insulating layer 30 and on a side of the second insulating layer 30 separated from the first insulating layer 20 in the first direction X. In this embodiment, the fourth adhesive portion 70 is located in the first block 101b1 of the region 101b.

[0078] The fourth adhesive portion 70 may include at least one polymer selected from the group consisting of cellulose, polyvinylidene fluoride-co-hexafluoropropylene, polyvinylidene fluoride-co-trichloroethylene, polymethyl methacrylate, polybutyl acrylate, polyacrylonitrile, polyvinylpyrrolidone, polyvinyl acetate, polyethylene-co-vinyl acetate, polyethylene oxide, polyarylate, cellulose acetate, cellulose acetate butyrate, cellulose acetate propionate, cyanoethyl pullulan, cyanoethyl polyvinyl alcohol, cyanoethyl cellulose, cyanoethyl sucrose, pullulan, carboxymethyl cellulose, and polypropylene-maleic anhydride, or a mixture of any combination of the above polymers, but is not limited to these.

[0079] When viewed from the third direction Z, the shape of the fourth adhesive portion 70 is not limited, and may be a circle (see FIG. 9A), a rectangle (see FIG. 14 and FIG. 15), a strip (see FIG. 16), other regular or irregular shapes, or a combination thereof. The number of the fourth adhesive portions 70 may be one or more according to actual needs. When the number of the fourth adhesive portions 70 is more than one, the multiple fourth adhesive portions 70 are provided at intervals (for example, distributed in a dot matrix). When viewed from the third direction Z, the battery 100 may include at least two fourth adhesive portions 70 (see FIG. 17) having different shapes. In some embodiments, when viewed from the third direction Z, the shapes of all the fourth adhesive portions 70 may be the same.

[0080] 18, 21A, and 21B, the case 80 is further adhered to the electrode assembly 10 by a fourth adhesive portion 70. When the number of the fourth adhesive portions 70 is plural, the fourth adhesive portions 70 may be provided with a space between each other after adhering the case 80, or adjacent fourth adhesive portions 70 may be connected to each other (see FIG. 16). In some embodiments, as shown in FIG. 21B, a groove 170' may be further provided in the case 80. A part of the fourth adhesive portion 70 is located in the groove 170'.

[0081] In one embodiment, the average orthogonal projection area of ​​the fourth adhesive portion 70 on the first surface 101 is larger than the average orthogonal projection area of ​​the first adhesive portion 40 on the first surface 101, so that the shear stress between the electrode assembly 10 and the case 80 during dropping can be concentrated on the first block 101b1, and the above shear stress can be prevented from being concentrated on the gap region 101a. This can prevent the pole pieces in the gap region 101a from being torn or pulled too hard, causing a short circuit between the positive and negative electrodes, and causing the battery 100 to fail.

[0082] In one embodiment, the average orthogonal projected area of ​​the third adhesive portion 60 on the first surface 101 is larger than the average orthogonal projected area of ​​the first adhesive portion 40 on the first surface 101 and is also larger than the average orthogonal projected area of ​​the second adhesive portion 50 on the first surface 101, so that the first insulating layer 20 or the second insulating layer 30 can be more tightly attached to the first surface 101. This can prevent the first insulating layer 20 or the second insulating layer 30 from falling off due to shear force when the battery is dropped.

[0083] 2, 21A and 22, the first insulating layer 20 and the second insulating layer 30 each further extend from the first surface 101 to the connection region 105. In this embodiment, the first insulating layer 20 and the second insulating layer 30 each further extend from the first surface 101 to the second portion 107. Furthermore, the first insulating layer 20 and the second insulating layer 30 each can further extend from the second portion 107 to the second surface 103. The first insulating layer 20 and the second insulating layer 30 are provided on the first surface 101, which can isolate the electrode assembly 10 from the case 80, and further reduce the contact between the electrode assembly 10 and the case 80, thereby reducing the possibility that the electrode assembly 10 will break the case 80, and at the same time, can avoid the case being damaged due to the drop of the active material in the region where the electrode assembly 10 is bonded to the first insulating layer 20 and the second insulating layer 30. In addition, when the battery 100 is dropped, the first insulating layer 20 and the second insulating layer 30 can further buffer between the electrode assembly 10 and the case 80, and can reduce the possibility of damage caused by a sharp object on the surface of the electrode assembly 10 colliding with the case 80. Meanwhile, when the first insulating layer 20 and the second insulating layer 30 extend to the second portion 107 and thus the second surface 103, the first insulating layer 20 and the second insulating layer 30 can further serve to fix the electrode assembly 10, suppressing the dispersion of the electrode assembly 10 and reducing the risk of short-circuiting of the positive and negative electrodes due to movement of parts in the electrode assembly 10 during the dropping process, thereby improving the safety of the battery 100. At this time, the area of ​​the projection of the first adhesive portion 40 on the first surface 101 along the third direction Z perpendicular to the first surface 101 can be smaller than the total area of ​​the orthogonal projection of the first insulating layer 20 and the second insulating layer 30 on the first surface 101. As described above, it is advantageous in the following respects. While the first insulating layer 20 and the second insulating layer 30 effectively suppress the dispersion of the electrode assembly 10, the first adhesive portion 40 improves the adhesion between the electrode assembly 10 and the case 80, thereby increasing the stability between the electrode assembly 10 and the case 80 and further improving the safety of the battery 100. Furthermore, the length of the region 101a in the first direction X can be smaller than half the length of the first surface 101 in the first direction X. Thus, it is further advantageous in the following respects.While the first insulating layer 20 and the second insulating layer 30 effectively suppress dispersion of the electrode assembly 10, the first adhesive portion 40 improves adhesion between the electrode assembly 10 and the case 80, thereby increasing the stability between the electrode assembly 10 and the case 80 and further improving the safety of the battery 100.

[0084] 23 and 24, the electrode assembly 10 may further include a third insulating layer 17. The third insulating layer 17 is provided on the second surface 103 and secures the outermost edge of the electrode assembly 10. The outermost edge of the electrode assembly 10 may be a positive electrode piece, a negative electrode piece, or a separator.

[0085] In some embodiments, the positions where the first insulating layer 20 and the second insulating layer 30 are provided are not limited thereto. For example, referring to FIG. 25, the first insulating layer 20 can further extend from the first portion 106 to the first surface 101 and not reach the second portion 107, and the second insulating layer 30 can further extend from the first portion 106 to the first surface 101 and not reach the second portion 107. The first surface 101 and the first portion 106 intersect at the second side 18. Furthermore, when viewed from the third direction Z, the first insulating layer 20 can extend from the second side 18 along the first surface 101 toward the second portion 107 and not reach the second portion 107, and the second insulating layer 30 can extend from the second side 18 along the first surface 101 toward the second portion 107 and not reach the second portion 107. 26, the first insulating layer 20 extends from the second portion 107 to the first surface 101 and does not reach the second portion 106, and the second insulating layer 30 extends from the first portion 106 to the first surface 101 and does not reach the second portion 107. In this case, the first direction X is a direction perpendicular to the second portion 107. In some embodiments, the electrode assembly 10 may have a laminated structure.

[0086] 24 and 27, in some embodiments, the fourth adhesive portion 70 may be further provided on the second surface 103, and may be further provided on the third insulating layer 17. When the first insulating layer 20 and the second insulating layer 30 extend to the second surface 103, the first adhesive portion 40, the second adhesive portion 50, and the third adhesive portion 60 may be similarly provided corresponding to the first insulating layer 20 and the second insulating layer 30 located on the second surface 103.

[0087] The manufacturing method of the above-mentioned battery 100 includes the steps of preparing an electrode assembly 10, adhering a first insulating layer 20 and a second insulating layer 30 to the electrode assembly 10, forming a first adhesive portion 40 on the surface of the electrode assembly 10 by, for example, but not limited to, screen printing, spot adhesion with a spray gun, etc., housing the electrode assembly 10 provided with the above-mentioned first adhesive portion 40, the first insulating layer 20, the second insulating layer 30 and the third insulating layer 17 in a case 80, and then pressing the outside of the case 80 so as to adhere the first adhesive portion 40 to the inside of the case 80.

[0088] The manufacturing method of the battery 100 may further include a step of attaching a third insulating layer 17 onto the electrode assembly 10 before forming the first adhesive portion 40. Preferably, the third insulating layer 17 is attached to the electrode assembly 10 before attaching the first insulating layer 20 and the second insulating layer 30 to the electrode assembly 10.

[0089] The manufacturing method of the battery 100 may further include a step of forming a second adhesive portion 50 on at least one surface of the first insulating layer 20 and the second insulating layer 30 by, for example, but not limited to, screen printing, spot bonding with a spray gun, etc., before housing the electrode assembly 10 in the case 80. Then, after pressing the outside of the case 80, the second adhesive portion 50 is bonded to the inside of the case 80.

[0090] The manufacturing method of the battery 100 may further include a step of forming a third adhesive portion 60 by, for example, but not limited to, screen printing, spot bonding with a spray gun, etc. on at least one surface of the first insulating layer 20 and the second insulating layer 30 and the surface of the electrode assembly 10 before housing the electrode assembly 10 in the case 80. Then, after pressing the outside of the case 80, the third adhesive portion 60 is bonded to the inside of the case 80.

[0091] The manufacturing method of the battery 100 may further include a step of forming a fourth adhesive portion 70 on the surface of the electrode assembly 10 by, for example, but not limited to, screen printing, spot bonding with a spray gun, etc., before housing the electrode assembly 10 in the case 80. Then, after pressing the outside of the case 80, the fourth adhesive portion 70 is bonded to the inside of the case 80.

[0092] The stacked electrode assembly 10' will now be described in further detail with reference to an example.

[0093] 7, the electrode assembly 10' is formed by directly stacking a plurality of laminates 10E along the Z direction, unlike the electrode assembly 10Ea (see FIG. 6) formed by stacking and winding the laminates 10E. Referring to FIG. 35A, the electrode assembly 10' includes eight edges perpendicular to the Z direction. In this embodiment, the first surface 101' is, for example, an area surrounded by the first side 16', the third side 19A, the second side 18', and the fourth side 19B connected in order when viewed from the Z direction shown in FIG. 35A. Among them, the third side 19A and the fourth side 19B are provided opposite to each other. The second surface 103' is, for example, an area surrounded by the first side 16A, the third side 19C, the second side 18A, and the fourth side 19D connected in order when viewed from the Z direction shown in FIG. 35A. The first side 16A and the second side 18A are opposite to each other, and the third side 19C and the fourth side 19D are opposite to each other. The first surface 101' is opposite to the second surface 103' and is a part of the outer surface of the electrode assembly 10'. The outer surface of the electrode assembly 10' further includes a connection region 105' connecting between the edge of the first surface 101' and the edge of the second surface 103'. In the stacked electrode assembly 10', each current collector may be provided with a metal portion 15'.

[0094] 35A, 35B, and 36A, in this embodiment, the connection region 105' includes a first portion 106', a third portion 108, a second portion 107', and a fourth portion 109, which are connected in sequence. The first portion 106' is provided on the opposite side of the second portion 107'. The third portion 108 is provided on the opposite side of the fourth portion 109.

[0095] The electrode assembly 10' may further include a metal portion 15' that extends from the first portion 106' in a direction away from the second portion 107'.

[0096] The first insulating layer 20 and the second insulating layer 30 are both provided on the first surface 101', and the first insulating layer 20 and the second insulating layer 30 are provided along the first direction X with an interval therebetween.

[0097] In this embodiment, when viewed from the third direction Z, the first insulating layer 20 may be, for example, rectangular. The first insulating layer 20 may include, for example, at least one of polyimide, polyvinyl chloride, polyethylene, and polypropylene, but is not limited thereto. When viewed from the third direction Z, the second insulating layer 30 may be, for example, rectangular. The second insulating layer 30 may include, for example, at least one of polyimide, polyvinyl chloride, polyethylene, and polypropylene, but is not limited thereto.

[0098] The first surface 101' and the second portion 107' meet at the first side 16'. In some embodiments, the first direction X is the direction in which the first side 16' is located. When viewed from the third direction Z, the first insulating layer 20 and the second insulating layer 30 each extend along the first surface 101' from the first side 16' towards the first portion 106' but do not reach the first portion 106'.

[0099] The length L1' of the first insulating layer 20 extending from the first side 16' to the first portion 106' and the length L2' of the second insulating layer 30 extending from the first side 16' to the first portion 106' are not particularly limited when the first insulating layer 20 does not reach the first portion 106' and when the second insulating layer 30 does not reach the first portion 106'. In this embodiment, the length L1' of the first insulating layer 20 extending from the first side 16' to the first portion 106' and the length L2' of the second insulating layer 30 extending from the first side 16' to the first portion 106' are equal. Here, the above length direction is defined as the second direction Y. In the embodiment, the length or width of two parts being equal should be understood to mean that the difference between the length or width of one part and the corresponding length or width of the other part is generally ±3 mm.

[0100] The first insulating layer 20 and the second insulating layer 30 may each include an adhesive layer and a substrate, which are laminated together. Here, the adhesive layer bonds the substrate and the electrode assembly 10'. The adhesive layer may include, for example, but is not limited to, at least one of natural rubber, synthetic rubber, acrylate, silica gel, and ethylene-vinyl acetate. The substrate may include, for example, but is not limited to, at least one of polyethylene, polypropylene, Teflon, polyvinyl chloride, polyimide, and nonwoven fabric.

[0101] 35A, 37, and 36B, when viewed from a third direction Z perpendicular to the first surface 101', the first adhesive portion 40 is provided on the first surface 101' and is located in a region 101a' between the first insulating layer 20 and the second insulating layer 30. In the second direction Y, the first adhesive portion 40 does not exceed the first insulating layer 20 and the second insulating layer 30. In some embodiments, the length of the region 101a' in the first direction X can be less than half the length of the first surface 101' in the first direction X.

[0102] In some embodiments, the area of ​​the orthogonal projection of the first adhesive portion 40 on the first surface 101', in other words, the area of ​​the projection of the first adhesive portion 40 on the first surface 101' along the third direction Z perpendicular to the first surface 101', can be smaller than the total area of ​​the orthogonal projections of the first insulating layer 20 and the second insulating layer 30 on the first surface 101'. Furthermore, in some embodiments, the area of ​​the orthogonal projection of the first adhesive portion 40 on the first surface 101' can be smaller than the area of ​​the orthogonal projection of the first insulating layer 20 on the first surface 101', and at the same time, can be smaller than the area of ​​the orthogonal projection of the second insulating layer 30 on the first surface 101'.

[0103] 38, the first distance H1 from at least a part of the region where the first surface 101' overlaps with the first insulating layer 20 to the second surface 103' is smaller than the second distance H2 from the first adhesive portion 40 to the second surface 103'. In order to ensure that the first distance H1 is smaller than the second distance H2, the distances from different positions in at least a part of the region where the first surface 101' overlaps with the first insulating layer 20 to the second surface 103' may be different. Furthermore, with combined reference to FIGS. 35A, 36B, and 38, the first distance H1 from at least a part of the region where the first side 16' overlaps with the first insulating layer 20, i.e., the end of the first surface 101' corresponding to the first insulating layer 20, to the second surface 103' is smaller than the second distance H2 from the first adhesive portion 40 to the second surface 103'.

[0104] 39, a first recess 120 is provided in the first surface 101', extending from the first side 16' toward the first portion 106'. At least a portion of the first insulating layer 20 away from the first portion 106' is provided in the first recess 120. In this embodiment, the first recess 120 may be an inclined groove, and the depth of the first recess 120 gradually decreases from the first side 16' toward the first portion 106' along the second direction Y. A portion of the first insulating layer 20 close to the first portion 106' may be located outside the first recess 120.

[0105] 35A, 36B, and 38 in combination, a third distance H3 from at least a part of the region where the first surface 101' overlaps with the second insulating layer 30 to the second surface 103' is smaller than the second distance H2. In order to ensure that the third distance H3 is smaller than the second distance H2, the distances from different positions in at least a part of the region where the first surface 101' overlaps with the second insulating layer 30 to the second surface 103' may be different. Furthermore, here, the third distance H3 from at least a part of the region where the first side 16' overlaps with the second insulating layer 30, i.e., the end of the first surface 101' corresponding to the second insulating layer 30, to the second surface 103' is smaller than the second distance H2.

[0106] 39, a second recess 130 is provided in the first surface 101', extending from the first side 16' toward the first portion 106'. At least a portion of the second insulating layer 30 away from the first portion 106' is provided in the second recess 130. In this embodiment, the second recess 130 may be an inclined groove, and the depth of the second recess 130 gradually decreases from the first side 16' toward the first portion 106' along the second direction Y. A portion of the second insulating layer 30 close to the first portion 106' may be located outside the second recess 130.

[0107] In some embodiments, the first distance H1 and the third distance H3 may be equal, referring to Figure 40. In some embodiments, the first distance H1 and the third distance H3 may not be equal.

[0108] 41 , the first surface 101′ may be provided with first grooves 140. The first adhesive portions 40 are located in the first grooves 140. In this embodiment, the number of the first adhesive portions 40 is multiple, the number of the first grooves 140 is multiple, and each first adhesive portion 40 is located in one first groove 140.

[0109] When viewed from the third direction Z, the shape and size of the first adhesive portion 40 are not limited, and may be a circle (see FIG. 36B), a rectangle (see FIG. 14 and FIG. 15), a strip (see FIG. 16), other regular or irregular shapes, or a combination thereof. The number of the first adhesive portions 40 may be one or more according to actual needs. When the number of the first adhesive portions 40 is more than one, the first adhesive portions 40 are provided at intervals (for example, distributed in a dot matrix). When viewed from the third direction Z, the battery 100 may include at least two first adhesive portions 40 with different shapes (see FIG. 17) or at least two first adhesive portions 40 with different sizes (see FIG. 36C). In some embodiments, referring to FIG. 36B, when viewed from the third direction Z, the shapes of all the first adhesive portions 40 may be the same.

[0110] 18 and 42, the battery 100 may further include a case 80. The case 80 may include, but is not limited to, one or more of an aluminum laminate film, a heat shrinkable film, an aluminum case, and a steel case. The case 80 encases the electrode assembly 10', the first insulating layer 20, and the second insulating layer 30, and is attached to the electrode assembly 10' by a first adhesive portion 40 (see FIGS. 43 and 44 at the same time). In some embodiments, as shown in FIG. 44, the case 80 may be provided with a groove 140'. A portion of the first adhesive portion 40 is located in the groove 140'. The first adhesive portion 40 is provided in the region 101a' between the first insulating layer 20 and the second insulating layer 30, so that the region in the battery 100 where the first insulating layer 20 and the second insulating layer 30 are provided and the region in the battery corresponding to the region 101a' can be more uniformly compressed in the horizontal direction (i.e., the first direction X and the second direction Y) during the formation process, which is advantageous in reducing the degree of deformation during the use of the battery 100. The first adhesive portion 40 is provided between the first insulating layer 20 and the second insulating layer 30, so that the adhesive force between the electrode assembly 10' and the case 80 can be improved, and therefore, when the battery 100 is subjected to an external force, the relative displacement between the electrode assembly 10' and the case 80 can be suppressed, and further, the possibility that the battery 100 is damaged by the external force can be reduced, and the service life of the battery 100 can be extended. At the same time, the first adhesive portion 40 adheres the case 80 to the electrode assembly 10', which also contributes to suppressing deformation of the electrode assembly 10'. The shape of the first adhesive parts 40 may change after bonding the case 80. When there are a plurality of first adhesive parts 40, the plurality of first adhesive parts 40 may be provided with intervals between each other after bonding the case 80, or adjacent first adhesive parts 40 may be connected to each other (see FIG. 16).

[0111] 35A, 37, 36B, and 38, the battery 100 may further include a second adhesive portion 50 provided on the surface 21 separated from the second surface 103' of the first insulating layer 20. The area of ​​the orthogonal projection of the second adhesive portion 50 on the first surface 101' is smaller than the area of ​​the orthogonal projection of the second adhesive portion 50 on the first surface 101' of the first insulating layer 20. The second adhesive portion 50 may be provided on the surface 31 separated from the second surface 103' of the second insulating layer 30. In this case, the area of ​​the orthogonal projection of the second adhesive portion 50 on the first surface 101' is smaller than the area of ​​the orthogonal projection of the second adhesive portion 50 on the first surface 101' of the second insulating layer 30.

[0112] The second adhesive portion 50 may include, for example, but is not limited to, at least one polymer selected from the group consisting of cellulose, polyvinylidene fluoride-co-hexafluoropropylene, polyvinylidene fluoride-co-trichloroethylene, polymethyl methacrylate, polybutyl acrylate, polyacrylonitrile, polyvinylpyrrolidone, polyvinyl acetate, polyethylene-co-vinyl acetate, polyethylene oxide, polyarylate, cellulose acetate, cellulose acetate butyrate, cellulose acetate propionate, cyanoethyl pullulan, cyanoethyl polyvinyl alcohol, cyanoethyl cellulose, cyanoethyl sucrose, pullulan, carboxymethyl cellulose, and polypropylene-maleic anhydride, or a mixture of any combination of the above polymers.

[0113] When viewed from the third direction Z, the shape of the second adhesive portion 50 is not limited and may be circular, rectangular, strip-like, other regular or irregular shapes, or a combination thereof. The number of the second adhesive portions 50 may be one or more according to actual needs. When the number of the second adhesive portions 50 is more than one, the second adhesive portions 50 are provided at intervals (e.g., distributed in a dot matrix). When viewed from the third direction Z, the battery 100 may include at least two second adhesive portions 50 with different shapes. In some embodiments, when viewed from the third direction Z, the shapes of all the second adhesive portions 50 may be the same.

[0114] 41, a second groove 150 is provided in a surface remote from the second surface 103' of the first insulating layer 20. The second adhesive portion 50 is located in the second groove 150.

[0115] 18, 45 and 46, the case 80 is bonded to the first insulating layer 20 by the second adhesive portion 50. The case 80 may be further bonded to the second insulating layer 30 by the second adhesive portion 50. The case 80 may be further bonded to the first insulating layer 20 and the second insulating layer 30 by the second adhesive portion 50. When the number of the second adhesive portions 50 is plural, the second adhesive portions 50 may be provided at intervals between the second adhesive portions 50 after bonding the case 80, or adjacent second adhesive portions 50 may be connected to each other. In some embodiments, as shown in FIG. 46, the case 80 may be provided with a groove 150'. A part of the second adhesive portion 50 is located in the groove 150'.

[0116] 35A, 37, and 36B, the battery 100 may further include a third adhesive portion 60. The third adhesive portion 60 is provided on a surface 21 separate from the second surface 103' of the first insulating layer 20, and extends to the first surface 101' across the boundary between the first insulating layer 20 and the first surface 101'.

[0117] The third adhesive portion 60 may include, for example, but is not limited to, at least one polymer selected from the group consisting of cellulose, polyvinylidene fluoride-co-hexafluoropropylene, polyvinylidene fluoride-co-trichloroethylene, polymethyl methacrylate, polybutyl acrylate, polyacrylonitrile, polyvinylpyrrolidone, polyvinyl acetate, polyethylene-co-vinyl acetate, polyethylene oxide, polyarylate, cellulose acetate, cellulose acetate butyrate, cellulose acetate propionate, cyanoethyl pullulan, cyanoethyl polyvinyl alcohol, cyanoethyl cellulose, cyanoethyl sucrose, pullulan, carboxymethyl cellulose, and polypropylene-maleic anhydride, or a mixture composed of any combination of the above polymers.

[0118] 18, 45 and 46, the third adhesive portion 60 is attached to the case 80. The case 80 can be adhered to the first insulating layer 20 by the third adhesive portion 60. The case 80 can be further adhered to the second insulating layer 30 by the third adhesive portion 60. The case 80 can be further adhered to the first insulating layer 20 and the second insulating layer 30 simultaneously by the third adhesive portion 60. In some embodiments, as shown in FIG. 46, a groove 160' may be provided in the case 80. A portion of the third adhesive portion 60 is located in the groove 160'.

[0119] 36B, 35A, 37, 45, and 46, the battery 100 may further include a fourth adhesive portion 70 provided in a region 101b' of the first surface 101'. The region 101b' is provided at a distance from the region of the first surface 101' where the first insulating layer 20 and the second insulating layer 30 are provided, and is provided at a distance from the region 101a' in the first surface 101, and the fourth adhesive portion 70 does not contact the first insulating layer 20 and the second insulating layer 30.

[0120] Specifically, referring to FIG. 36B, the region 101b' includes a first block 101b1' and a second block 101b2'. The first block 101b1' is separated from the region 101a' in the second direction Y. The second block 101b2' is located on a side of the first insulating layer 20 separated from the second insulating layer 30 and on a side of the second insulating layer 30 separated from the first insulating layer 20 in the first direction X. In this embodiment, the fourth adhesive portion 70 is located in the first block 101b1' of the region 101b'.

[0121] The fourth adhesive portion 70 may include at least one polymer selected from the group consisting of cellulose, polyvinylidene fluoride-co-hexafluoropropylene, polyvinylidene fluoride-co-trichloroethylene, polymethyl methacrylate, polybutyl acrylate, polyacrylonitrile, polyvinylpyrrolidone, polyvinyl acetate, polyethylene-co-vinyl acetate, polyethylene oxide, polyarylate, cellulose acetate, cellulose acetate butyrate, cellulose acetate propionate, cyanoethyl pullulan, cyanoethyl polyvinyl alcohol, cyanoethyl cellulose, cyanoethyl sucrose, pullulan, carboxymethyl cellulose, and polypropylene-maleic anhydride, or a mixture of any combination of the above polymers, but is not limited to these.

[0122] When viewed from the third direction Z, the shape of the fourth adhesive portion 70 is not limited, and may be a circle (see FIG. 36B), a rectangle (see FIG. 14 and FIG. 15), a strip (see FIG. 16), other regular or irregular shapes, or a combination thereof. The number of the fourth adhesive portions 70 may be one or more according to actual needs. When the number of the fourth adhesive portions 70 is more than one, the multiple fourth adhesive portions 70 are provided at intervals (for example, distributed in a dot matrix). When viewed from the third direction Z, the battery 100 may include at least two fourth adhesive portions 70 (see FIG. 17) having different shapes. In some embodiments, when viewed from the third direction Z, the shapes of all the fourth adhesive portions 70 may be the same.

[0123] 18, 45, and 46, the case 80 is further adhered to the electrode assembly 10' by a fourth adhesive portion 70. When the number of the fourth adhesive portions 70 is plural, the fourth adhesive portions 70 may be provided with a space between each other after adhering the case 80, or adjacent fourth adhesive portions 70 may be connected to each other (see FIG. 16). In some embodiments, as shown in FIG. 46, a groove 170' may be provided in the case 80. A part of the fourth adhesive portion 70 is located in the groove 170'.

[0124] 37, 45 and 47, the first insulating layer 20 and the second insulating layer 30 each further extend from the first surface 101' to the connection region 105'. In this embodiment, the first insulating layer 20 and the second insulating layer 30 each extend from the first surface 101' to the second portion 107'. Furthermore, the first insulating layer 20 and the second insulating layer 30 each can continue to extend from the second portion 107' to the second surface 103'. The first insulating layer 20 and the second insulating layer 30 are provided on the first surface 101', which can isolate the electrode assembly 10' from the case 80, and further reduce the contact between the electrode assembly 10' and the case 80, which can reduce the possibility that the electrode assembly 10' will break the case 80, and at the same time, can avoid the case being damaged due to the drop of the active material in the region where the electrode assembly 10' is bonded to the first insulating layer 20 and the second insulating layer 30. In addition, when the battery 100 is dropped, the first insulating layer 20 and the second insulating layer 30 can further buffer between the electrode assembly 10' and the case 80, thereby reducing the possibility of the electrode assembly 10' being damaged due to a sharp object on the surface thereof colliding with the case 80. Meanwhile, when the first insulating layer 20 and the second insulating layer 30 extend to the second portion 107' and thus the second surface 103', the first insulating layer 20 and the second insulating layer 30 can further serve to fix the electrode assembly 10' and suppress the electrode assembly 10' from scattering.

[0125] In some embodiments, the positions where the first insulating layer 20 and the second insulating layer 30 are provided are not limited thereto. For example, referring to FIG. 48 and FIG. 59, the first insulating layer 20 can further extend from the first portion 106' to the first surface 101' and not reach the second portion 107', and the second insulating layer 30 can further extend from the first portion 106' to the first surface 101' and not reach the second portion 107'. The first surface 101' and the first portion 106' intersect at the second side 18'. Furthermore, when viewed from the third direction Z, the first insulating layer 20 can extend from the second side 18' along the first surface 101' toward the second portion 107' and not reach the second portion 107', and the second insulating layer 30 can extend from the second side 18' along the first surface 101' toward the second portion 107' and not reach the second portion 107'. 49, the first insulating layer 20 extends from the second portion 107' to the first surface 101' but does not reach the first portion 106', and the second insulating layer 30 extends from the first portion 106' to the first surface 101' but does not reach the second portion 107'. In this case, the first direction X is perpendicular to the second portion 107'.

[0126] 50 and 51, in some embodiments, the fourth adhesive portion 70 may be further provided on the second surface 103'. When the first insulating layer 20 and the second insulating layer 30 extend to the second surface 103', the first adhesive portion 40, the second adhesive portion 50, and the third adhesive portion 60 may be similarly provided corresponding to the first insulating layer 20 and the second insulating layer 30 located on the second surface 103'.

[0127] In some embodiments, referring to Figures 52 and 53, the first insulating layer 20 further extends from the third portion 108 to the first surface 101' and does not reach the fourth portion 109, and the second insulating layer 30 further extends from the fourth portion 109 to the first surface 101' and does not reach the third portion 108. The first surface 101' and the third portion 108 intersect at the third side 19A, and the first surface 101' and the fourth portion 109 intersect at the fourth side 19B. Furthermore, when viewed from the third direction Z, the first insulating layer 20 can extend from the third side 19A along the first surface 101' toward the fourth portion 109 and does not reach the fourth portion 109, and the second insulating layer 30 can extend from the fourth side 19B along the first surface 101' toward the third portion 108 and does not reach the third portion 108.

[0128] 54A to 59, one first insulating layer 20 may be provided, or multiple first insulating layers 20 may be provided at intervals. The size may be set as needed. One second insulating layer 30 may be provided, or multiple second insulating layers 30 may be provided at intervals. The size may be set as needed. In some embodiments, multiple first insulating layers 20 and / or multiple second insulating layers 30 are also applicable to the electrode assembly 10 having a wound structure.

[0129] As shown in FIG. 54B, one of the first insulating layers 20 and one of the second insulating layers 30 can further extend from the third portion 108 to the first surface 101' and not reach the fourth portion 109, and the other of the first insulating layer 20 and the other of the second insulating layer 30 can further extend from the fourth portion 109 to the first surface 101' and not reach the third portion 108.

[0130] As shown in Figs. 52 to 58, in some embodiments, the metal portion 15' includes a plurality of first metal portions 151 and a plurality of second metal portions 153. The first metal portion 151 is provided on the first portion 106', and the second metal portion 153 is provided on the second portion 107'. As shown in Fig. 59, in some embodiments, the first metal portion 151 and the second metal portion 153 are provided at intervals on the second portion 107'. In some embodiments, the first metal portion 151 is provided on the first portion 106' and the second metal portion 153 is provided on the second portion 107', which is also applicable to the electrode assembly 10 having a wound structure.

[0131] In some embodiments, for example, referring to FIG. 60, the first insulating layer 20 may further extend from the first portion 106' through the first surface 101' to the second portion 107', and the second insulating layer 30 may further extend from the first portion 106' through the first surface 101' to the second portion 107'. Furthermore, the first insulating layer 20 may further extend from the first portion 106' to the second surface 103', and may further extend from the second portion 107' to the second surface 103'. The second insulating layer 30 may further extend from the first portion 106' to the second surface 103', and may further extend from the second portion 107' to the second surface 103'. Furthermore, the first insulating layer 20 may be annular and provided on the first surface 101', the first portion 106', the second surface 103', and the second portion 107'. The second insulating layer 30 may be annular and provided on the first surface 101', the first portion 106', the second surface 103', and the second portion 107'. Also, referring to FIG. 61, the first insulating layer 20 may further extend from the third portion 108 through the first surface 101' to the fourth portion 109, and the second insulating layer 30 may further extend from the third portion 108 through the first surface 101' to the fourth portion 109. Furthermore, the first insulating layer 20 may further extend from the third portion 108 to the second surface 103', and may further extend from the fourth portion 109 to the second surface 103'. The second insulating layer 30 may further extend from the third portion 108 to the second surface 103', and may further extend from the fourth portion 109 to the second surface 103'. Furthermore, the first insulating layer 20 may be annular and is provided on the first surface 101', the third portion 108, the second surface 103', and the fourth portion 109. The second insulating layer 30 may be annular and is provided on the first surface 101', the third portion 108, the second surface 103', and the fourth portion 109. In some embodiments, the first insulating layer 20 and the second insulating layer 30 in FIG. 60 are similarly applicable to an electrode assembly 10 having a wound structure.

[0132] In some embodiments, the battery assembly 10 is formed by stacking a plurality of laminates 10E of different sizes along the third direction Z. For example, referring to Figs. 62 to 66, the battery assembly 10 is formed by stacking a first laminate 10Ea, a second laminate 10Eb, and a third laminate 10Ec of increasing size in order along the third direction Z. When viewed from the third direction Z, the surface of the first laminate 10Ea observed is the first surface 101', the part of the second laminate 10Eb exposed from the first laminate 10Ea is the first step surface 102a, and the part of the third laminate 10Ec exposed from the second laminate 10Eb is the second step surface 102b. The surface of the third laminate 10Ec separated from the first surface 101' is the second surface 103'. The connection region 105' includes the first step surface 102a and the second step surface 102b.

[0133] In some embodiments, for example, referring to FIG. 62 and FIG. 65A, the first portion 106' is a surface provided along the Z direction. The second portion 107', the third portion 108, and the fourth portion 109 are each stepped, and each includes a part of the first step surface 102a and a part of the second step surface 102b. The first insulating layer 20 may be provided on the first surface 101' and extend from the first surface 101' to the first step surface 102a and the second step surface 102b corresponding to the third portion 108. Furthermore, the first insulating layer 20 may further extend from the second step surface 102b corresponding to the third portion 108 to the second surface 103'. The second insulating layer 30 may be provided on the first surface 101' and extend from the first surface 101' to the first step surface 102a and the second step surface 102b corresponding to the fourth portion 109. Furthermore, the second insulating layer 30 may further extend from the second step surface 102b corresponding to the fourth portion 109 to the second surface 103'. In this regard, as shown in Fig. 64 and Fig. 65A, the second adhesive portion 50, the third adhesive portion 60, and the fourth adhesive portion 70 provided corresponding to the first step surface 102a do not exceed the first laminate 10Ea in the Z direction, and the second adhesive portion 50, the third adhesive portion 60, and the fourth adhesive portion 70 provided corresponding to the second step surface 102b do not exceed the second laminate 10Eb in the Z direction. Also, as shown in Fig. 65B and Fig. 66, there may be a second adhesive portion 50 provided corresponding to the first step surface 102a and extending to the first surface 101', and there may be a second adhesive portion 50 provided corresponding to the second step surface 102b and extending to the first step surface 102a. That is, the second adhesive portion 50 is present across two parallel surfaces to bond two adjacent laminates. This can improve the structural stability of the electrode assembly. In another embodiment, the third adhesive portion 60 and / or the fourth adhesive portion 70 may be present that is provided in correspondence with the first step surface 102a and extends to the first surface 101', and the third adhesive portion 60 and / or the fourth adhesive portion 70 may be present that is provided in correspondence with the second step surface 102b and extends to the first step surface 102a. That is, the third adhesive portion 60 and / or the fourth adhesive portion 70 are present across two parallel surfaces.67, the second adhesive portion 50 corresponding to the first step surface 102a and extending to the first surface 101', the second adhesive portion 50 corresponding to the second step surface 102b and extending to the first step surface 102a, the third adhesive portion 60 and the fourth adhesive portion 70 corresponding to the first step surface 102a and extending to the first surface 101', and the third adhesive portion 60 and the fourth adhesive portion 70 corresponding to the second step surface 102b and extending to the first step surface 102a may be present at the same time. Among them, the third adhesive portion 60 is advantageous for improving the adhesive strength between the insulating layer and the electrode assembly. In some embodiments, the second adhesive portion 50 across two parallel surfaces, the third adhesive portion 60 across two parallel surfaces, and the fourth adhesive portion 70 across two parallel surfaces may be present alone, or any two of the second adhesive portion 50 across two parallel surfaces, the third adhesive portion 60 across two parallel surfaces, and the fourth adhesive portion 70 across two parallel surfaces may be present, and may be provided as needed.

[0134] As another example, referring to FIG. 63, the first portion 106' and the fourth portion 109 are surfaces provided along the Z direction. The second portion 107' and the third portion 108 are each stepped, and each includes a part of the first step surface 102a and a part of the second step surface 102b. The first insulating layer 20 may be provided on the first surface 101' and extend from the first surface 101' to the first portion 106'. Furthermore, the first insulating layer 20 may continue to extend from the first portion 106' to the second surface 103'. The second insulating layer 30 may be provided on the first surface 101' and extend from the first surface 101' to the first step surface 102a and the second step surface 102b corresponding to the second portion 107'. Furthermore, the second insulating layer 30 may further continue to extend from the second step surface 102b corresponding to the second portion 107' to the second surface 103'. Among them, as shown in FIG. 64, the second adhesive portion 50, the third adhesive portion 60, and the fourth adhesive portion 70 provided corresponding to the first step surface 102a do not extend beyond the first laminate 10Ea in the Z direction, and the second adhesive portion 50, the third adhesive portion 60, and the fourth adhesive portion 70 provided corresponding to the second step surface 102b do not extend beyond the second laminate 10Eb in the Z direction.

[0135] The present invention will be further described with reference to specific examples and comparative examples below, in which the electrode assemblies 10 used in the examples and comparative examples all have the same structure and model number.

[0136] Comparative Example 1 28, the electrode assembly is provided with a first insulating layer and a second insulating layer, and the first insulating layer and the second insulating layer extend from the first surface through the second portion to the second surface, respectively, to fix the electrode assembly. A case (aluminum laminate film) accommodates the electrode assembly and is fixed to the electrode assembly by the adhesive. After the electrolyte is injected and the case is sealed, a battery is obtained. After the battery is subjected to a formation process, the battery is activated in capacity by performing a standard process of charging and discharging, and finally the battery is subjected to a degassing process to complete the manufacturing process.

[0137] Comparative Example 2 Referring to FIG. 29, the difference between Comparative Example 2 and Comparative Example 1 is that an adhesive portion is provided in a first region on the first surface of the electrode assembly that is located on the side away from the first insulating layer and the second portion of the second insulating layer.

[0138] Example 1 30, Example 1 is distinguished from Comparative Example 2 in that the adhesive portion is further provided in a second region on the first surface of the electrode assembly other than the region where the first insulating layer and the second insulating layer are provided and the first region. That is, the second region includes the region between the first insulating layer and the second insulating layer, the region of the first insulating layer separated from the second insulating layer, and the region of the second insulating layer separated from the first insulating layer.

[0139] Example 2 Referring to FIG. 31, the difference between Example 2 and Example 1 is that adhesive portions are further provided at the boundary between the first surface and a surface separate from the first surface of the first insulating layer, the surface separate from the first surface of the first insulating layer, the boundary between the first surface and a surface separate from the first surface of the second insulating layer, and the surface separate from the first surface of the second insulating layer.

[0140] Example 3 Referring to FIG. 32, the difference between Example 3 and Comparative Example 2 is that the adhesive portion is further provided in the region located between the first insulating layer and the second insulating layer on the first surface of the electrode assembly.

[0141] Example 4 Referring to FIG. 33, the difference between Example 4 and Comparative Example 1 is that the adhesive portion is provided only in the region located on the first surface of the electrode assembly, between the first insulating layer and the second insulating layer.

[0142] The batteries of Comparative Examples 1-2 and Examples 1-4 are charged at room temperature with a current of 0.2C, and the thickness of the battery is measured after full charging. Next, the above batteries are discharged to the cutoff voltage, and further charged at a current of 0.8C with a constant current and constant voltage to the limit voltage. The thickness of each region of the battery is measured and set as the initial thickness (here, the thickness of the region where the first insulating layer is provided on the battery is D1, or the thickness of the region where the second insulating layer is provided on the battery is D2, and the thickness of the region between the first insulating layer and the second insulating layer of the battery is D3, specifically, see FIG. 34. In this case, the region where the battery of Comparative Example 1, which does not have the first insulating layer and the second insulating layer, is measured corresponds to the region where the battery of Comparative Example / Example, which has the first insulating layer and the second insulating layer, is measured.), and the difference value ΔD between D3 and D1 or the difference value ΔD between D3 and D2 is calculated and recorded in Table 1 below. Next, the battery was cycled 700 times at a charge / discharge rate of 0.8C / 1C. After the 700 cycles, the thickness of each of the above regions, i.e., the thickness after cycling, was measured again, and the difference between D3 and D1 or the difference between D3 and D2, ΔD, was calculated and recorded in Table 1 below.

[0143] [Table 1]

[0144] As can be seen from the above data, the provision of the first and second insulating layers can suppress the swelling of the battery. After the battery is subjected to charge-discharge cycles, the deformation amount of the battery with the adhesive between the first and second insulating layers is obviously smaller than that of the battery without the adhesive between the first and second insulating layers. The two opposite surfaces connecting the first part (i.e., the head part) and the second part (i.e., the bottom part) in the connection region of the electrode assembly are defined as the third part and the fourth part, respectively. After charging the batteries of Comparative Examples 1-2 and Examples 1-4 to the limit voltage at room temperature with a current of 0.2C, the batteries are subjected to a drop test. Specifically, the batteries are fixed to a drop test box for batteries with a special adhesive, and the drop test box with the batteries is grasped by a robot arm and dropped on a marble slab at a height of 1.8m according to a preset drop method. The preset drop method is to perform six drops each time in the order of first surface down → second surface down → first part down → third part down → second part down → fourth part down. After each drop, the surface of the battery (i.e., the aluminum laminate film) was observed to see if it was damaged, and the open circuit voltage of the battery was measured. If the open circuit voltage of the battery is less than 3.0 V, the battery is judged to have expired, and if the aluminum laminate film on the surface of the battery is damaged, the battery is also judged to have expired. For each set of comparative examples or examples, five batteries are measured each time and the average value is calculated. The number of times each battery was dropped when it expired, the cause of the expiration, and the damage state of the battery when it expired are recorded in Table 2.

[0145] [Table 2]

[0146] As can be seen from the above data, providing an adhesive in the region between the first and second insulating layers is more advantageous in improving failure due to dropping the battery than not providing an adhesive, and is therefore more advantageous in improving battery safety. And providing the first and second insulating layers and an adhesive can improve the failure situation due to dropping the battery, and is therefore more advantageous in improving battery safety.

[0147] In the battery of the present invention, a first insulating layer and a second insulating layer are provided on the surface of the electrode assembly, and a first adhesive is provided between the first insulating layer and the second insulating layer. When the electrode assembly is packaged in a case, the first adhesive adheres the electrode assembly and the case. When the battery is subjected to an external force, it is advantageous to reduce damage to the case of the electrode assembly, and at the same time, it is advantageous to protect the electrode assembly itself, thereby improving the safety of the battery and extending the service life of the battery.

[0148] In addition, those skilled in the art may make other corresponding modifications and variations based on the technical solutions and technical ideas of the present invention, and all such modifications and variations shall fall within the scope of protection of the present invention. [Explanation of symbols]

[0149] [Table 3] [Table 4] [Table 5]

Claims

1. an electrode assembly including a first surface and a second surface opposite the first surface; a first insulating layer provided on the first surface; a second insulating layer provided on the first surface and spaced apart from the first insulating layer; at least one first adhesive portion provided on the first surface and located in a region between the first insulating layer and the second insulating layer; Including batteries.

2. The battery of claim 1 , wherein the battery includes two or more of the first adhesive portions, and the two or more first adhesive portions are distributed in a dot matrix.

3. 2. The battery of claim 1, further comprising a second adhesive portion provided on a side of the first insulating layer opposite the first surface.

4. The battery according to claim 3 , wherein an area of ​​the second adhesive portion as orthogonally projected on the first surface is smaller than an area of ​​the first insulating layer as orthogonally projected on the first surface.

5. The battery according to claim 3 , wherein the battery includes at least two of the second adhesive portions, and the at least two second adhesive portions are distributed in a dot matrix.

6. 2. The battery of claim 1, wherein the first insulating layer extends from the first surface to the second surface and the second insulating layer extends from the first surface to the second surface.

7. 7. The battery of claim 6, further comprising a metal portion at one end of the electrode assembly, the first insulating layer and the second insulating layer being located at an end of the electrode assembly remote from the metal portion.

8. The battery of claim 1 , wherein an area of ​​an orthogonal projection of the at least one first adhesive portion on the first surface is smaller than a total area of ​​an orthogonal projection of the first insulating layer and the second insulating layer on the first surface.

9. 9. The battery of claim 8, wherein an area of ​​an orthogonal projection of the at least one first adhesive portion on the first surface is smaller than an area of ​​an orthogonal projection of the first insulating layer on the first surface and smaller than an area of ​​an orthogonal projection of the second insulating layer on the first surface.

10. 2. The battery of claim 1, wherein a distance from a portion of an area where the first surface and the first insulating layer contact each other to the second surface is a first distance, and a distance from the first adhesive portion to the second surface is a second distance, and the first distance is smaller than the second distance.

11. 11. The battery of claim 10, wherein a distance from a portion of an area where the first surface and the second insulating layer contact each other to the second surface is a third distance, the third distance being less than the second distance.

12. 12. The battery of claim 11, wherein the first distance and the third distance are not equal.

13. The battery of claim 1 , wherein the length of the first adhesive portion in the first direction is less than half the length of the first surface in the first direction.

14. The battery according to claim 1 , wherein the first surface has a first groove corresponding to the first adhesive portion, and the first adhesive portion is located within the first groove.

15. The battery according to claim 3 , wherein a second groove is provided on a surface of the first insulating layer corresponding to the second adhesive portion, and the second adhesive portion is located within the second groove.

16. 2. The battery of claim 1, further comprising a third adhesive portion provided on a surface of the first insulating layer separate from the second surface, the third adhesive portion extending to an area of ​​the first surface where the first insulating layer is not provided.

17. 2. The battery of claim 1, further comprising a fourth adhesive portion, the fourth adhesive portion being provided on the first surface, the region of the first surface where the fourth adhesive portion is provided being spaced apart from the region of the first surface where the first insulating layer and the second insulating layer are provided and being spaced apart from the region of the first surface between the first insulating layer and the second insulating layer, and the fourth adhesive portion not in contact with either the first insulating layer or the second insulating layer.

18. The battery of claim 17 , wherein the electrode assembly includes at least two fourth adhesive portions having different orthogonal projection shapes, and the fourth adhesive portions are distributed in a dot matrix.

19. 2. The battery of claim 1, wherein the electrode assembly further comprises a third insulating layer, the electrode assembly having a wound structure, the third insulating layer being provided on the second surface and fixing an end of an outermost pole piece of the electrode assembly.

20. 2. The battery of claim 1, further comprising a case that encases the electrode assembly, the first insulating layer and the second insulating layer and is attached to the electrode assembly by the first adhesive.

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