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 a battery.

Background Art

[0002] With the maturity of applications such as consumer electronics and electric vehicles, users are increasingly paying attention to the application risks for the entire device. For example, the requirements for the shock resistance of electronic products are increasing. As an important component of electronic products, the battery is similarly required to have shock resistance. When the electronic product is subjected to an impact, the electrode assembly housed in the battery case is likely to break the case, or the electrode assembly itself is damaged by the impact, which affects the safety and service life of the battery.

Summary of the Invention

[0003] In view of the above situation, it is necessary to provide a battery that is advantageous for improving shock resistance and safety.

[0004] The present invention provides a battery including an electrode assembly, a first insulating layer, a second insulating layer, and at least one first bonding portion. The electrode assembly includes a first surface and a second surface provided on the opposite side of 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 provided at an interval from the first insulating layer. The first bonding portion is provided on the first surface and is located in the region between the first insulating layer and the second insulating layer.

[0005] As one aspect of the present invention, the battery includes two or more first bonding portions, and the two or more first bonding portions are distributed in a dot matrix.

[0006] As one aspect of the present invention, the battery further includes a second bonding portion provided on the side of the first surface of the first insulating layer away from the first surface.

[0007] As one aspect of the present invention, the area of the orthographic projection on the first surface of the second bonding portion is smaller than the area of the orthographic projection on the first surface of the first insulating layer.

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

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

[0010] In one aspect 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 the end of the electrode assembly away from the metal portion.

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

[0012] In one aspect of the present invention, the orthographic projection area on the first surface of at least one first adhesive portion is smaller than the orthographic projection area on the first surface of the first insulating layer, and also smaller than the orthographic projection area on the first surface of the second insulating layer.

[0013] In one aspect of the present invention, the distance from a portion of the region where the first surface and the first insulating layer are in contact to the second surface is the first distance, the distance from the first adhesive portion to the second surface is the second distance, and the first distance is smaller than the second distance.

[0014] In one aspect of the present invention, the distance from a portion of the region where the first surface and the second insulating layer are in contact to the second surface is the third distance, and the third distance is smaller than the second distance.

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

[0016] In one aspect of the present invention, 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.

[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 aspect of the present invention, the battery further includes a third adhesive portion provided on a surface separated from the second surface of the first insulating layer, the third adhesive portion extending to a region on the first surface where the first insulating layer is not provided.

[0020] In one aspect of the present invention, the battery further includes a fourth adhesive portion, the fourth adhesive portion being provided on the first surface, the region on the first surface where the fourth adhesive portion is provided being spaced apart from the region on the first surface where the first insulating layer and the second insulating layer are provided, and also spaced apart from the region between the first insulating layer and the second insulating layer on the first surface, and the fourth adhesive portion not in contact with either the first insulating layer or the second insulating layer.

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

[0022] In one aspect of the present invention, the electrode assembly further includes a third insulating layer, the electrode assembly has a wound structure, the third insulating layer is provided on the second surface and fixes the ends of the outermost electrode pieces of the electrode assembly.

[0023] In one aspect of the present invention, the battery further includes a case, the case encloses the electrode assembly, the first insulating layer and the second insulating layer, and is bonded to the electrode assembly by a first adhesive portion.

[0024] In one aspect of the present invention, the average orthographic projection area on the first surface of the fourth adhesive portion is greater than the average orthographic projection area on the first surface of the first adhesive portion.

[0025] As one aspect of the present invention, the average orthographic projection area on the first surface of the third adhesive portion is larger than the average orthographic projection area on the first surface of the first adhesive portion and also larger than the average orthographic 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 the surface of the electrode assembly, and a first adhesive portion is provided between the first insulating layer and the second insulating layer. When packaging the electrode assembly with a case, the first adhesive portion adheres the electrode assembly and the case.

[0027] When the battery is subjected to an external force, it is advantageous for improving the safety of the battery and extending the service life of the battery.

Brief Description of the Drawings

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

[0029] The present invention will be further described below, combining embodiments for carrying out the invention with the above drawings. [Modes for carrying out the invention]

[0030] The following describes the technical concepts in the embodiments of the present invention clearly and in detail. Clearly, the embodiments described are only a selection of the embodiments of the present invention, not all embodiments. Unless otherwise defined, all technical and scientific terms used herein have the same meaning as those generally understood by those skilled in the art to which the present invention pertains. The terms used in the specification of the present invention are for the purpose of describing specific embodiments only and are not intended to limit the present invention.

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

[0032] In the drawings, various assembly and layer sizes and thicknesses are enlarged for convenience and clarity. The same number indicates the same element throughout. As used herein, the terms “and / or” and “and / or” include any one or more related listed items and all combinations thereof. It should be understood that when element A is said to “connect” element B, element A may be directly connected to element B, or an intermediate element C may be present so that elements A and B are indirectly connected to each other.

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

[0034] The technical terms used herein are for the purpose of describing specific embodiments and are not intended to limit the invention. As used herein, singular forms include plural forms unless otherwise specified in the specification. The term “including,” as used herein, means that there are listed features, values, steps, actions, elements and / or components, but should be further understood not to exclude the presence or addition of one or more other features, values, steps, actions, elements, components and / or combinations thereof.

[0035] In this specification, spatial terms such as “above” are used for convenience to describe the relationship between one element or feature shown in the drawings and another element(s) or feature(s). Spatial terms should be understood as intended to include different orientations of a device or apparatus in use or operation, in addition to the directions shown in the drawings. For example, an element described as “above” or “up” another element or feature would be oriented “below” or “down” the other element or feature if the device in the drawing were inverted. Therefore, the exemplary term “above” can include both upward and downward directions. In this specification, terms such as first, second, third, etc., may be used to describe various elements, components, regions, layers, and / or parts, but it should be understood that these elements, components, regions, layers, and / or parts should not be limited by these terms. These terms are used to distinguish one element, component, region, layer, or part from another. Therefore, the first element, component, region, layer, or portion described below may be referred to as the second element, component, region, layer, or portion without departing from the teaching of the exemplary embodiments. In the present invention, the first direction may be any direction in the plane on which the first surface is located.

[0036] Several embodiments of the present invention will be described in detail below. The embodiments and features described later may be combined with each other if they do not contradict each other.

[0037] Referring to Figure 1, the 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 Figure 1, the electrode assembly 10 includes a first surface 101, a second surface 103 provided on the opposite side of the first surface 101, and a connecting region 105 connecting the first surface 101 and the second surface 103.

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

[0040] For example, the electrode assembly 10 shown in Figure 1 has a structure formed by winding several times, where the electrode assembly 10 has multiple bends in one direction, i.e., in the X direction in the figure, and each of the multiple bends is distributed on both sides relative to the center of the battery 100 along the X direction, i.e., on both the left and right sides in Figure 1. Here, the connection point between one outer plane of the electrode assembly 10 and the end closest to the center of the battery 100 at the outermost bend on the left side of the center of the battery 100 is the first end 101A, and the connection point between the outer plane of the electrode assembly 10 and the end closest to the center of the battery 100 at the outermost bend 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, the region enclosed by the first end 101A, the second end 101B, and the two ends of the electrode assembly 10 along the Y direction, namely the first side 16 and the second side 18, when viewed from the Z direction as shown in Figure 1.

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

[0043] The following provides a further explanation of the electrode assembly 10, using an example.

[0044] Referring to Figure 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 the surface 10a of the first conductive layer 10A. The second conductive layer 10C is formed on the 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 the 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] Referring to Figures 3 and 4, the first conductive layer 10A may have a rectangular shape when viewed from a direction perpendicular to the surface 10a. The first conductive layer 10A may be formed, for example, by laminating a current collector 10AA and an active material layer 10AB together. The current collector 10AA may include, but is not limited to, one or more types of conductive metal sheets such as aluminum mesh and aluminum foil. The active material layer 10AB may include, but is not limited to, one or more types of, lithium cobalt oxide, lithium nickel cobalt manganese oxide, lithium nickel cobalt aluminate, lithium manganese oxide, lithium nickel oxide, lithium manganese iron phosphate, lithium vanadium phosphate, oxo vanadilithyl phosphate, lithium iron phosphate, lithium titanate, and lithium-rich manganese-based materials. The first conductive layer 10A may, for example, be used as a positive electrode piece when constituting the electrode assembly 10 of the battery 100.

[0046] Referring to Figure 3, the first separator layer 10B may, for example, be rectangular when viewed from a direction perpendicular to the surface 10b. The first separator layer 10B may contain, but is not limited to, one or more of the following materials: polyethylene, polypropylene, polyethylene terephthalate, polyimide, and aramid. The first separator layer 10B may, for example, be used as a separator when forming the electrode assembly 10 of the battery 100.

[0047] Referring to Figures 3 and 5, the second conductive layer 10C may, for example, be rectangular when viewed from a direction perpendicular to the surface 10c. The second conductive layer 10C may be formed, for example, by laminating a current collector 10CA and an active material layer 10CB together. The current collector 10CA may, but is not limited to, one or two types of conductive metal sheets such as nickel foil and copper foil. The active material layer 10CB may, but is not limited to, one or more types of metals such as graphite, soft carbon, hard carbon, graphene, mesocarbon microbeads, silicon-based materials, tin-based materials, lithium titanate, or other metals that can form alloys with lithium. The second conductive layer 10C may, for example, be used as a negative electrode piece when constituting the electrode assembly 10 of the battery 100.

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

[0049] Referring to Figure 6, the electrode assembly 10 can be formed, for example, by winding up a laminate 10Ea which is made up of multiple laminates 10E stacked together. Alternatively, referring to Figure 7, for example, the electrode assembly 10 can be formed by directly stacking multiple 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 that is separated from the first surface 101. Furthermore, the outer surface of the electrode assembly 10 includes a connection region 105 in a third direction Z that is perpendicular to the first surface 101.

[0051] In this embodiment, the second surface 103 corresponds to the region enclosed by the first end 101A, the second end 101B, and the two ends along the Y direction of the electrode assembly 10, namely the first side 16 and the second side 18, in the plane opposite to the first surface 101 of the electrode assembly 10 when viewed from the Z direction as shown in Figure 1.

[0052] Referring to Figures 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 electrode piece 11, and the other end can be connected to other electronic elements to enable electrical conductivity between the electrode assembly 10 and other electronic elements.

[0053] Both the first insulating layer 20 and the second insulating layer 30 are provided on the first surface 101, and the first insulating layer 20 and the second insulating layer 30 are provided with an interval between them along the first direction X.

[0054] In this embodiment, the first insulating layer 20 may be rectangular when viewed from the third direction Z. The first insulating layer 20 may contain, but is not limited to, one or more of the following materials: polyimide, polyvinyl chloride, polyethylene, and polypropylene. The second insulating layer 30 may be rectangular when viewed from the third direction Z. The second insulating layer 30 may contain, but is not limited to, one or more of the following materials: polyimide, polyvinyl chloride, polyethylene, and polypropylene.

[0055] The first surface 101 and the second portion 107 intersect at the first edge 16. In some embodiments, the first direction X is the direction in which the first edge 16 is located. Viewed from the third direction Z, the first insulating layer 20 and the second insulating layer 30 extend along the first surface 101 from the first edge 16 toward 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 and the length L2 of the second insulating layer 30 extending from the first side 16 toward the first portion 106 are equal. 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 a laminated adhesive layer and a substrate. Here, the adhesive layer adheres the substrate and the electrode assembly 10. The adhesive layer may, but is not limited to, at least one or more of, for example, natural rubber, synthetic rubber, acrylate, silica gel, or ethylene vinyl acetate. The substrate may, but is not limited to, at least one or more of, for example, polyethylene, polypropylene, Teflon®, polyvinyl chloride, polyimide, or nonwoven fabric.

[0058] Referring to Figures 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 located in 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 extend beyond 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 orthographic area of ​​the first adhesive portion 40 on the first surface 101, in other words, the projection area of ​​the first adhesive portion 40 on the first surface 101 along a third direction Z perpendicular to the first surface 101, can be smaller than the total orthographic area of ​​the first insulating layer 20 and the second insulating layer 30 on the first surface 101. Furthermore, in some embodiments, the orthographic area of ​​the first adhesive portion 40 on the first surface 101 can be smaller than the orthographic area of ​​the first insulating layer 20 on the first surface 101, and simultaneously smaller than the orthographic area of ​​the second insulating layer 30 on the first surface 101. The first adhesive portion 40 may, but is not limited to, include at least one polymer from among cellulose, polyvinylidene-co-hexafluoropropylene, polyvinylidene-co-trichloroethylene, polymethyl methacrylate, butyl polyacrylate, polyacrylonitrile, polyvinylpyrrolidone, polyvinyl acetate, polyethylene-co-vinyl acetate, polyethylene oxide, polyarylate, cellulose acetate, cellulose acetate butyrate, cellulose acetate propionate, cyanoethyl pullulan, cyanoethyl polyvinyl alcohol, cyanoethylcellulose, cyanoethyl saccharose, pullulan, carboxymethylcellulose, and polypropylene-maleic anhydride, or any combination of the above polymers.

[0060] Referring to Figure 10, the first distance H1 from at least a portion 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 locations in at least a portion of the area where the first surface 101 overlaps with the first insulating layer 20 to the second surface 103 may be different. Furthermore, referring to Figures 1, 9A and 10 in combination, here, the first distance H1 from at least a portion of the area where the first edge 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] Specifically, referring to Figure 11, a first recess 120 is provided on the first surface 101, extending from the first side 16 toward the first portion 106. In the first insulating layer 20, at least the portion 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 its depth gradually decreases along the second direction Y from the first side 16 toward the first portion 106. In the first insulating layer 20, the portion closer to the first portion 106 may be located outside the first recess 120.

[0062] Referring to Figures 1, 9A, and 10 in combination, the third distance H3 from at least a portion of the area 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 locations in at least a portion of the area where the first surface 101 overlaps with the second insulating layer 30 to the second surface 103 may be different. Furthermore, the third distance H3 from at least a portion of the area where the first edge 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] Referring to Figure 11, a second recess 130 is provided on the first surface 101, extending from the first side 16 toward the first portion 106. In the second insulating layer 30, at least the portion 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 its depth gradually decreases along the second direction Y from the first side 16 toward the first portion 106. In the second insulating layer 30, the portion closer to the first portion 106 may be located outside the second recess 130.

[0064] In some further embodiments, referring to Figure 12, the first distance H1 and the third distance H3 do not necessarily have to be equal.

[0065] Referring to Figure 13, a first groove 140 can be provided on the first surface 101. The first adhesive portion 40 is located within the first groove 140. In this embodiment, there are multiple first adhesive portions 40 and multiple first grooves 140, and each first adhesive portion 40 is located within one first groove 140.

[0066] Viewed from a third direction Z, the shape and size of the first adhesive portion 40 are not limited and may be circular (see Figure 9A), rectangular (see Figures 14 and 15), strip-shaped (see Figure 16), or other regular or irregular shapes or combinations thereof. The number of first adhesive portions 40 may be one or more, depending on the actual need. If there are multiple first adhesive portions 40, they may be spaced apart (for example, distributed in a dot matrix). Viewed from a third direction Z, the battery 100 may include at least two first adhesive portions 40 of different shapes (see Figure 17) and at least two first adhesive portions 40 of different sizes (see Figure 9B). In some embodiments, referring to Figure 9A, the shapes of all first adhesive portions 40 may be identical when viewed from a third direction Z.

[0067] Referring to Figures 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 the following: an aluminum laminate film, a heat-shrinkable film, an aluminum case, or a steel case. The case 80 encloses the electrode assembly 10, the first insulating layer 20, and the second insulating layer 30, and is bonded to the electrode assembly 10 by a first adhesive portion 40 (referring simultaneously to Figures 20A and 20B). In some embodiments, the case 80 may be provided with a groove 140', as shown in Figure 20B. A portion of the first adhesive portion 40 is located within 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. This allows 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 region 101a, to have a more uniform degree of compression 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. This improves the adhesive strength between the electrode assembly 10 and the case 80. Therefore, when the battery 100 is subjected to external force, it suppresses the relative displacement between the electrode assembly 10 and the case 80, further reducing the possibility of the battery 100 being damaged by external force and extending the service life of the battery 100. At the same time, since the first adhesive portion 40 adheres the case 80 to the electrode assembly 10, it also contributes to suppressing deformation of the electrode assembly 10. The shape of the first adhesive portion 40 after it has bonded to the case 80 may change. If there are multiple first adhesive portions 40, after bonding the case 80, the multiple first adhesive portions 40 may be spaced apart from each other, or adjacent first adhesive portions 40 may be connected to each other (see Figure 16). If the multiple first adhesive portions 40 are distributed in a dot matrix, the placement of the first adhesive portions 40 can be made more flexible, the position where the first adhesive portions 40 are provided can be made more precise, and at the same time, the thickness after the first adhesive portions 40 have bonded to the case 80 can be made more consistent.

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

[0069] The second adhesive portion 50 may, but is not limited to, include at least one polymer from among cellulose, polyvinylidene-co-hexafluoropropylene, polyvinylidene-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, cyanoethylcellulose, cyanoethyl saccharose, pullulan, carboxymethylcellulose, and polypropylene-maleic anhydride, or any combination of the above polymers.

[0070] Viewed from a third direction Z, the shape of the second adhesive portion 50 is not limited and may be circular, rectangular, strip-shaped, other regular or irregular shapes, or combinations thereof. The number of second adhesive portions 50 may be one or more, depending on the actual need. If there are multiple second adhesive portions 50, they may be spaced apart (for example, distributed in a dot matrix). Viewed from a third direction Z, the battery 100 may include at least two second adhesive portions 50 with different shapes. In some embodiments, when viewed from a third direction Z, the shapes of all second adhesive portions 50 may be identical.

[0071] In some embodiments, referring to Figure 13, a second groove 150 is provided on the surface of the first insulating layer 20 that is separated from the second surface 103. The second adhesive portion 50 is located within the second groove 150.

[0072] Referring to Figures 18, 21A, and 21B, the case 80 is bonded to the first insulating layer 20 by the second adhesive portion 50, which is advantageous for stability between the electrode assembly 10 and the case 80. Furthermore, the case 80 is bonded to the second insulating layer 30 by the second adhesive portion 50, which is also advantageous for stability between the electrode assembly 10 and the case 80. The case 80 can further be bonded to the first insulating layer 20 and the second insulating layer 30 by the second adhesive portion 50. By using the second adhesive portion 50, direct bonding of the case 80 to the electrode assembly 10 is avoided. During the process of the battery 100 falling, the second adhesive portion 50 adheres not to the case 80 and the electrode assembly 10, but to the case 80 and the first insulating layer 20, or to the case 80 and the second insulating layer 30. Furthermore, the orthographic area of ​​the first surface 101 of the second adhesive portion 50 is smaller than the orthographic area of ​​the first surface 101 of the first insulating layer 20 or the second insulating layer 30 to which the second adhesive portion 50 adheres. In other words, the area in contact between the first insulating layer 20 or the second insulating layer 30 and the electrode assembly 10 is large. Therefore, the case 80 distributes the tensile force on the electrode assembly 10 by the second adhesive portion 50, reducing the probability of damage to the electrode assembly 10 due to pulling, and thereby reducing the risk of short circuits between the positive and negative electrodes. If there are multiple second adhesive portions 50, after bonding the case 80, the multiple second adhesive portions 50 may be spaced apart from each other, or adjacent second adhesive portions 50 may be connected to each other. If the multiple second adhesive portions 50 are distributed in a dot matrix, the placement of the second adhesive portions 50 is more flexible, the position where the second adhesive portions 50 are provided can be made more precise, and at the same time, the thickness after the second adhesive portions 50 are bonded to the case 80 can be made more consistent. In some embodiments, as shown in Figure 21B, the case 80 may be further provided with grooves 150'. A portion of the second adhesive portion 50 is located within the grooves 150'.

[0073] Referring to Figures 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 of the first insulating layer 20 that is separated from the second surface 103, and extends across the boundary between the first insulating layer 20 and the first surface 101 to the first surface 101.

[0074] The third adhesive portion 60 may, but is not limited to, include at least one polymer from among cellulose, polyvinylidene-co-hexafluoropropylene, polyvinylidene-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, cyanoethylcellulose, cyanoethyl saccharose, pullulan, carboxymethylcellulose, and polypropylene-maleic anhydride, or any combination of the above polymers.

[0075] Referring to Figures 18, 21A, and 21B, the third adhesive portion 60 is attached to the case 80. The case 80 can be bonded to the first insulating layer 20 by the third adhesive portion 60. The case 80 can further be bonded to the second insulating layer 30 by the third adhesive portion 60. The case 80 can further be bonded 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 Figure 21B, the case 80 may be provided with a groove 160'. A portion of the third adhesive portion 60 is located within the groove 160'.

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

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

[0078] The fourth adhesive portion 70 may, but is not limited to, include at least one polymer from among cellulose, polyvinylidene-co-hexafluoropropylene, polyvinylidene-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, cyanoethylcellulose, cyanoethyl saccharose, pullulan, carboxymethylcellulose, and polypropylene-maleic anhydride, or any combination of the above polymers.

[0079] Viewed from a third direction Z, the shape of the fourth adhesive portion 70 is not limited and may be circular (see Figure 9A), rectangular (see Figures 14 and 15), strip-shaped (see Figure 16), or other regular or irregular shapes or combinations thereof. The number of fourth adhesive portions 70 may be one or more, depending on the actual need. If there are multiple fourth adhesive portions 70, they may be spaced apart (for example, distributed in a dot matrix). Viewed from a third direction Z, the battery 100 may include at least two fourth adhesive portions 70 with different shapes (see Figure 17). In some embodiments, when viewed from a third direction Z, all the shapes of the fourth adhesive portions 70 may be identical.

[0080] Referring to Figures 18, 21A, and 21B, the case 80 is further bonded to the electrode assembly 10 by a fourth adhesive portion 70. If there are multiple fourth adhesive portions 70, after bonding the case 80, the multiple fourth adhesive portions 70 may be spaced apart from each other, or adjacent fourth adhesive portions 70 may be connected to each other (see Figure 16). In some embodiments, as shown in Figure 21B, a groove 170' may be provided in the case 80. A portion of the fourth adhesive portion 70 is located within the groove 170'.

[0081] In one embodiment, the average orthographic projection area of ​​the first surface 101 of the fourth adhesive portion 70 is larger than the average orthographic projection area of ​​the first surface 101 of the first adhesive portion 40. This allows the shear stress between the electrode assembly 10 and the case 80 to be concentrated in the first block 101b1 when dropped, preventing the shear stress from being concentrated in the gap region 101a. This prevents the electrode pieces in the gap region 101a from being torn or severely pulled, thus preventing a short circuit between the positive and negative electrodes and causing the battery 100 to fail.

[0082] In one embodiment, the average orthographic projection area of ​​the first surface 101 of the third adhesive portion 60 is larger than the average orthographic projection area of ​​the first surface 101 of the first adhesive portion 40, and also larger than the average orthographic projection area of ​​the first surface 101 of the second adhesive portion 50. As a result, the first insulating layer 20 or the second insulating layer 30 can be more tightly bonded to the first surface 101. This prevents the first insulating layer 20 or the second insulating layer 30 from falling off due to shear force when the battery is dropped.

[0083] Referring to Figures 2, 21A, and 22, the first insulating layer 20 and the second insulating layer 30 each extend further 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 can each be further extended from the second portion 107 to the second surface 103. By providing the first insulating layer 20 and the second insulating layer 30 on the first surface 101, the electrode assembly 10 and the case 80 can be isolated, further reducing contact between the electrode assembly 10 and the case 80, decreasing the possibility of the electrode assembly 10 damaging the case 80, and at the same time preventing damage to the case due to the fall of active material in the region where the electrode assembly 10 is bonded to the first insulating layer 20 and the second insulating layer 30. Furthermore, 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, reducing the possibility of damage caused by sharp edges on the surface of the electrode assembly 10 colliding with the case 80. On the other hand, when the first insulating layer 20 and the second insulating layer 30 extend to the second portion 107 and subsequently to the second surface 103, the first insulating layer 20 and the second insulating layer 30 can further play a role in fixing the electrode assembly 10, suppressing the dispersion of the electrode assembly 10 and reducing the risk of short circuits between the positive and negative electrodes due to movement of components 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 positive projections of the first insulating layer 20 and the second insulating layer 30 on the first surface 101. Thus, the following points are advantageous. The first insulating layer 20 and the second insulating layer 30 effectively suppress the dispersion of the electrode assembly 10, and 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 less than half the length of the first surface 101 in the first direction X. Thus, the following points are also advantageous.The first insulating layer 20 and the second insulating layer 30 effectively suppress the dispersion of the electrode assembly 10, and 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 battery safety 100.

[0084] Referring to Figures 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 fixes 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 in which the first insulating layer 20 and the second insulating layer 30 are provided are not limited thereto. For example, referring to Figure 25, the first insulating layer 20 may further extend from the first portion 106 to the first surface 101 but not to the second portion 107, and the second insulating layer 30 may further extend from the first portion 106 to the first surface 101 but not to the second portion 107. The first surface 101 and the first portion 106 intersect at the second edge 18. Furthermore, viewed from a third direction Z, the first insulating layer 20 may extend along the first surface 101 from the second edge 18 toward the second portion 107 but not to the second portion 107, and the second insulating layer 30 may extend along the first surface 101 from the second edge 18 toward the second portion 107 but not to the second portion 107. As another example, referring to Figure 26, the first insulating layer 20 extends from the second portion 107 to the first surface 101 but does not reach the second 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. In some embodiments, the electrode assembly 10 may have a laminated structure.

[0086] In some embodiments, referring to Figures 24 and 27, the fourth adhesive portion 70 may be provided on the second surface 103 and also 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 can similarly be provided corresponding to the first insulating layer 20 and the second insulating layer 30 located on the second surface 103.

[0087] The manufacturing method for the battery 100 described above includes the steps of: preparing an electrode assembly 10; attaching 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 means of, for example, screen printing, spot bonding with a spray gun, etc., but not limited to these methods; housing the electrode assembly 10, which is provided with the 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 that the first adhesive portion 40 is bonded to the inside of the case 80.

[0088] The method for manufacturing the battery 100 may further include the step of attaching a third insulating layer 17 to 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 for the battery 100 may further include the 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, for example by 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 for the battery 100 may further include the step of forming a third adhesive portion 60 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, for example by 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 third adhesive portion 60 is bonded to the inside of the case 80.

[0091] The manufacturing method for the battery 100 may further include the step of forming a fourth adhesive portion 70 on the surface of the electrode assembly 10, before housing the electrode assembly 10 in the case 80, by means of, for example, screen printing, spot bonding with a spray gun, etc., but not limited to these methods. 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 following provides a further explanation of the stacked electrode assembly 10', using an example.

[0093] Referring to Figure 7, the electrode assembly 10' differs from the electrode assembly 10Ea (see Figure 6), which is formed by stacking and winding laminates 10E, in that it is formed by directly stacking multiple laminates 10E along the Z direction. Referring to Figure 35A, the electrode assembly 10' includes eight edges perpendicular to the Z direction. In this embodiment, the first surface 101', when viewed from the Z direction as shown in Figure 35A, is the region enclosed by the first side 16', the third side 19A, the second side 18', and the fourth side 19B in that order. Within this region, the third side 19A and the fourth side 19B are provided opposite each other. The second surface 103', when viewed from the Z direction as shown in Figure 35A, is the region enclosed by the first side 16A, the third side 19C, the second side 18A, and the fourth side 19D in that order. Among these, the first side 16A and the second side 18A are provided opposite each other, and the third side 19C and the fourth side 19D are provided opposite each other. The first surface 101' is provided on the opposite side of the second surface 103' and is part of the outer surface of the electrode assembly 10'. The outer surface of the electrode assembly 10' further includes a connection region 105' that connects the edge of the first surface 101' and the edge of the second surface 103'. In the stacked electrode assembly 10', a metal part 15' may be provided on each current collector.

[0094] In this embodiment, referring to Figures 35A, 35B, and 36A, the connection region 105' includes, in order, a first portion 106', a third portion 108, a second portion 107', and a fourth portion 109. The first portion 106' is located on the opposite side of the second portion 107'. The third portion 108 is located on the opposite side of the fourth portion 109.

[0095] The electrode assembly 10' may further include a metal portion 15' that protrudes in a direction away from the first portion 106' and 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 spaced apart along the first direction X.

[0097] In this embodiment, when viewed from a third direction Z, the first insulating layer 20 may be, for example, rectangular. The first insulating layer 20 may contain, but is not limited to, one or more of the following materials: polyimide, polyvinyl chloride, polyethylene, and polypropylene. When viewed from a third direction Z, the second insulating layer 30 may be, for example, rectangular. The second insulating layer 30 may contain, but is not limited to, one or more of the following materials: polyimide, polyvinyl chloride, polyethylene, and polypropylene.

[0098] The first surface 101' and the second portion 107' intersect at the first edge 16'. In some embodiments, the first direction X is the direction in which the first edge 16' is located. Viewed from the third direction Z, the first insulating layer 20 and the second insulating layer 30 extend along the first surface 101' from the first edge 16' toward 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' 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' and the length L2' of the second insulating layer 30 extending from the first side 16' toward the first portion 106' are equal. Here, the length direction is defined as the second direction Y. In this embodiment, the equal length or width of two parts should generally 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 ±3 mm.

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

[0101] Referring to Figures 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 located in the 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 extend beyond 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 orthographic area of ​​the first surface 101' of the first adhesive portion 40, in other words, the projection area of ​​the first surface 101' of the first adhesive portion 40 along a third direction Z perpendicular to the first surface 101', can be smaller than the total orthographic area of ​​the first surface 101' of the first insulating layer 20 and the second insulating layer 30. Furthermore, in some embodiments, the orthographic area of ​​the first surface 101' of the first adhesive portion 40 can be smaller than the orthographic area of ​​the first surface 101' of the first insulating layer 20, and at the same time, smaller than the orthographic area of ​​the first surface 101' of the second insulating layer 30.

[0103] Referring to Figure 38, the first distance H1 from at least a portion 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 distance from different locations in at least a portion of the area where the first surface 101' overlaps with the first insulating layer 20 to the second surface 103' may be different. Furthermore, referring to Figures 35A, 36B, and 38 in combination, the first distance H1 from at least a portion 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'.

[0104] Specifically, referring to Figure 39, a first recess 120 is provided on the first surface 101', extending from the first side 16' toward the first portion 106'. In the first insulating layer 20, at least the portion 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 its depth gradually decreases along the second direction Y from the first side 16' toward the first portion 106'. In the first insulating layer 20, the portion closer to the first portion 106' may be located outside the first recess 120.

[0105] Referring to Figures 35A, 36B, and 38 in combination, the third distance H3 from at least a portion of the area 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 locations in at least a portion of the area where the first surface 101' overlaps with the second insulating layer 30 to the second surface 103' may be different. Furthermore, the third distance H3 from at least a portion of the area 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] Referring to Figure 39, a second recess 130 is provided on the first surface 101', extending from the first side 16' toward the first portion 106'. In the second insulating layer 30, at least the portion 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 its depth gradually decreases along the second direction Y from the first side 16' toward the first portion 106'. In the second insulating layer 30, the portion closer to the first portion 106' may be located outside the second recess 130.

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

[0108] Referring to Figure 41, a first groove 140 can be provided on the first surface 101'. The first adhesive portion 40 is located within the first groove 140. In this embodiment, there are multiple first adhesive portions 40 and multiple first grooves 140, and each first adhesive portion 40 is located within one first groove 140.

[0109] Viewed from a third direction Z, the shape and size of the first adhesive portion 40 are not limited and may be circular (see Figure 36B), rectangular (see Figures 14 and 15), strip-shaped (see Figure 16), or other regular or irregular shapes or combinations thereof. The number of first adhesive portions 40 may be one or more, depending on the actual need. If there are multiple first adhesive portions 40, they may be spaced apart (for example, distributed in a dot matrix). Viewed from a third direction Z, the battery 100 may include at least two first adhesive portions 40 of different shapes (see Figure 17) and at least two first adhesive portions 40 of different sizes (see Figure 36C). In some embodiments, referring to Figure 36B, all first adhesive portions 40 may have the same shape when viewed from a third direction Z.

[0110] Referring to Figures 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 the following: an aluminum laminate film, a heat-shrinkable film, an aluminum case, or a steel case. The case 80 encloses the electrode assembly 10', the first insulating layer 20, and the second insulating layer 30, and is bonded to the electrode assembly 10' by the first adhesive portion 40 (refer to Figures 43 and 44 simultaneously). In some embodiments, the case 80 may be provided with a groove 140', as shown in Figure 44. A portion of the first adhesive portion 40 is located within 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. This allows the region in the battery 100 where the first insulating layer 20 and the second insulating layer 30 are provided, and the region corresponding to region 101a' in the battery, to have a more uniform degree of compression 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, provided between the first insulating layer 20 and the second insulating layer 30, improves the adhesive strength between the electrode assembly 10' and the case 80. Therefore, when the battery 100 is subjected to external force, it suppresses the relative displacement between the electrode assembly 10' and the case 80, further reducing the possibility of the battery 100 being damaged by external force and extending the service life of the battery 100. At the same time, since the first adhesive portion 40 adheres the case 80 to the electrode assembly 10', it also contributes to suppressing deformation of the electrode assembly 10'. The shape of the first adhesive portion 40 after it has been bonded to the case 80 may change. If there are multiple first adhesive portions 40, after they have been bonded to the case 80, the multiple first adhesive portions 40 may be spaced apart from each other, or adjacent first adhesive portions 40 may be connected to each other (see Figure 16).

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

[0112] The second adhesive portion 50 may, but is not limited to, include at least one polymer from among cellulose, polyvinylidene-co-hexafluoropropylene, polyvinylidene-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, cyanoethylcellulose, cyanoethyl saccharose, pullulan, carboxymethylcellulose, and polypropylene-maleic anhydride, or any combination of the above polymers.

[0113] Viewed from a third direction Z, the shape of the second adhesive portion 50 is not limited and may be circular, rectangular, strip-shaped, other regular or irregular shapes, or combinations thereof. The number of second adhesive portions 50 may be one or more, depending on the actual need. If there are multiple second adhesive portions 50, they may be spaced apart (for example, distributed in a dot matrix). Viewed from a third direction Z, the battery 100 may include at least two second adhesive portions 50 with different shapes. In some embodiments, when viewed from a third direction Z, the shapes of all second adhesive portions 50 may be identical.

[0114] In some embodiments, referring to Figure 41, a second groove 150 is provided on the surface of the first insulating layer 20 that is separated from the second surface 103'. The second adhesive portion 50 is located within the second groove 150.

[0115] Referring to Figures 18, 45, and 46, the case 80 is bonded to the first insulating layer 20 by the second adhesive portion 50. The case 80 can be further bonded to the second insulating layer 30 by the second adhesive portion 50. The case 80 can be further bonded to the first insulating layer 20 and the second insulating layer 30 by the second adhesive portion 50. If there are multiple second adhesive portions 50, after bonding the case 80, the multiple second adhesive portions 50 may be spaced apart from each other, or adjacent second adhesive portions 50 may be connected to each other. In some embodiments, as shown in Figure 46, a groove 150' may be provided in the case 80. A portion of the second adhesive portion 50 is located within the groove 150'.

[0116] Referring to Figures 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 of the first insulating layer 20 that is separated from the second surface 103' and extends across the boundary between the first insulating layer 20 and the first surface 101' to the first surface 101'.

[0117] The third adhesive portion 60 may, but is not limited to, include at least one polymer from among cellulose, polyvinylidene-co-hexafluoropropylene, polyvinylidene-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, cyanoethylcellulose, cyanoethyl saccharose, pullulan, carboxymethylcellulose, and polypropylene-maleic anhydride, or any combination of the above polymers.

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

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

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

[0121] The fourth adhesive portion 70 may, but is not limited to, include at least one polymer from among cellulose, polyvinylidene-co-hexafluoropropylene, polyvinylidene-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, cyanoethylcellulose, cyanoethyl saccharose, pullulan, carboxymethylcellulose, and polypropylene-maleic anhydride, or any combination of the above polymers.

[0122] Viewed from a third direction Z, the shape of the fourth adhesive portion 70 is not limited and may be circular (see Figure 36B), rectangular (see Figures 14 and 15), strip-shaped (see Figure 16), or other regular or irregular shapes or combinations thereof. The number of fourth adhesive portions 70 may be one or more, depending on the actual need. If there are multiple fourth adhesive portions 70, they may be spaced apart (for example, distributed in a dot matrix). Viewed from a third direction Z, the battery 100 may include at least two fourth adhesive portions 70 with different shapes (see Figure 17). In some embodiments, when viewed from a third direction Z, all the shapes of the fourth adhesive portions 70 may be identical.

[0123] Referring to Figures 18, 45, and 46, the case 80 is further bonded to the electrode assembly 10' by a fourth adhesive portion 70. If there are multiple fourth adhesive portions 70, after bonding the case 80, the multiple fourth adhesive portions 70 may be spaced apart from each other, or adjacent fourth adhesive portions 70 may be connected to each other (see Figure 16). In some embodiments, as shown in Figure 46, the case 80 may be provided with a groove 170'. A portion of the fourth adhesive portion 70 is located within the groove 170'.

[0124] Referring to Figures 37, 45, and 47, the first insulating layer 20 and the second insulating layer 30 each extend further 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 can each be extended further from the second portion 107' to the second surface 103'. By providing the first insulating layer 20 and the second insulating layer 30 on the first surface 101', the electrode assembly 10' and the case 80 can be isolated, further reducing contact between the electrode assembly 10' and the case 80, decreasing the possibility of the electrode assembly 10' damaging the case 80, and at the same time preventing damage to the case due to the fall of active material in the region where the electrode assembly 10' is bonded to the first insulating layer 20 and the second insulating layer 30. Furthermore, 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, reducing the possibility of damage caused by sharp edges on the surface of the electrode assembly 10' colliding with the case 80. On the other hand, when the first insulating layer 20 and the second insulating layer 30 extend to the second portion 107' and subsequently to the second surface 103', the first insulating layer 20 and the second insulating layer 30 further play a role in fixing the electrode assembly 10', thereby suppressing the dispersion of the electrode assembly 10'.

[0125] In some embodiments, the positions in which the first insulating layer 20 and the second insulating layer 30 are provided are not limited thereto. For example, referring to Figures 48 and 59, the first insulating layer 20 may 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 may 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 edge 18'. Furthermore, viewed from a third direction Z, the first insulating layer 20 may extend along the first surface 101' from the second edge 18' toward the second portion 107' and not reach the second portion 107', and the second insulating layer 30 may extend along the first surface 101' from the second edge 18' toward the second portion 107' and not reach the second portion 107'. As another example, referring to Figure 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] In some embodiments, referring to Figures 50 and 51, the fourth adhesive portion 70 may also be 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 can similarly be 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 may extend further from the third portion 108 to the first surface 101' and not reach the fourth portion 109, and the second insulating layer 30 may extend further from the fourth portion 109 to the first surface 101' and not reach the third portion 108. The first surface 101' and the third portion 108 intersect at the third edge 19A, and the first surface 101' and the fourth portion 109 intersect at the fourth edge 19B. Furthermore, viewed from the third direction Z, the first insulating layer 20 may extend along the first surface 101' from the third edge 19A toward the fourth portion 109 and not reach the fourth portion 109, and the second insulating layer 30 may extend along the first surface 101' from the fourth edge 19B toward the third portion 108 and not reach the third portion 108.

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

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

[0130] As shown in Figures 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 portions 151 are provided in the first portion 106', and the second metal portions 153 are provided in the second portion 107'. As shown in Figure 59, in some embodiments, the first metal portions 151 and the second metal portions 153 are provided in the second portion 107' with a gap between them. In some embodiments, the provision of the first metal portions 151 in the first portion 106' and the second metal portions 153 in the second portion 107' is similarly applicable to an electrode assembly 10 having a wound structure.

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

[0132] In some embodiments, the battery assembly 10 is comprised of multiple stacks 10E of different sizes stacked along a third direction Z. For example, referring to Figures 62 to 66, the battery assembly 10 is comprised of a first stack 10Ea, a second stack 10Eb, and a third stack 10Ec, which are sequentially stacked along the third direction Z in increasing order of size. Viewed from the third direction Z, the observed surface of the first stack 10Ea is the first surface 101', the portion of the second stack 10Eb exposed from the first stack 10Ea is the first stepped surface 102a, and the portion of the third stack 10Ec exposed from the second stack 10Eb is the second stepped surface 102b. The surface of the third stack 10Ec that is separated from the first surface 101' is the second surface 103'. The connection region 105' includes the first stepped surface 102a and the second stepped surface 102b.

[0133] In some embodiments, for example, referring to Figures 62 and 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 include a portion of the first stepped surface 102a and a portion of the second stepped surface 102b, respectively. The first insulating layer 20 is provided on the first surface 101' and may extend from the first surface 101' to the first stepped surface 102a and the second stepped surface 102b corresponding to the third portion 108. Furthermore, the first insulating layer 20 may further extend from the second stepped surface 102b corresponding to the third portion 108 to the second surface 103'. The second insulating layer 30 is provided on the first surface 101' and may extend from the first surface 101' to the first stepped surface 102a and the second stepped surface 102b corresponding to the fourth portion 109. Furthermore, the second insulating layer 30 may extend further from the second stepped surface 102b corresponding to the fourth portion 109 to the second surface 103'. In this case, as shown in Figures 64 and 65A, the second adhesive portion 50, the third adhesive portion 60, and the fourth adhesive portion 70 provided corresponding to the first stepped 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 stepped surface 102b do not exceed the second laminate 10Eb in the Z direction. Also, as shown in Figures 65B and 66, there may be a second adhesive portion 50 provided corresponding to the first stepped surface 102a and extending to the first surface 101', and there may be a second adhesive portion 50 provided corresponding to the second stepped surface 102b and extending to the first stepped surface 102a. That is, there is a second adhesive portion 50 that spans two parallel surfaces to bond two adjacent laminates. This improves the structural stability of the electrode assembly. In other embodiments, there may be a third adhesive portion 60 and / or a fourth adhesive portion 70 that is provided corresponding to the first stepped surface 102a and extends to the first surface 101', or there may be a third adhesive portion 60 and / or a fourth adhesive portion 70 that is provided corresponding to the second stepped surface 102b and extends to the first stepped surface 102a. That is, there is a third adhesive portion 60 and / or a fourth adhesive portion 70 that spans two parallel surfaces.As shown in Figure 67, a second adhesive portion 50 provided corresponding to the first stepped surface 102a and extending to the first surface 101', a second adhesive portion 50 provided corresponding to the second stepped surface 102b and extending to the first stepped surface 102a, a third adhesive portion 60 and a fourth adhesive portion 70 provided corresponding to the first stepped surface 102a and extending to the first surface 101', and a third adhesive portion 60 and a fourth adhesive portion 70 provided corresponding to the second stepped surface 102b and extending to the first stepped surface 102a may exist simultaneously. Among these, the third adhesive portion 60 is advantageous in improving the strength of the adhesion between the insulating layer and the electrode assembly. In some embodiments, the second adhesive portion 50, the third adhesive portion 60, and the fourth adhesive portion 70 spanning the two parallel surfaces may exist individually, or any two of the second adhesive portion 50, the third adhesive portion 60, and the fourth adhesive portion 70 may exist, and may be provided as needed.

[0134] As another example, referring to Figure 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 stepped and each includes a portion of the first stepped surface 102a and a portion of the second stepped surface 102b, respectively. The first insulating layer 20 is provided on the first surface 101' and may 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 is provided on the first surface 101' and may extend from the first surface 101' to the first stepped surface 102a and the second stepped surface 102b corresponding to the second portion 107'. Furthermore, the second insulating layer 30 may further extend from the second stepped surface 102b corresponding to the second portion 107' to the second surface 103'. As shown in Figure 64, the second adhesive portion 50, the third adhesive portion 60, and the fourth adhesive portion 70, which are provided corresponding to the first stepped 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, which are provided corresponding to the second stepped surface 102b, do not exceed the second laminate 10Eb in the Z direction.

[0135] The following provides further explanation with specific examples and comparative examples. In all of these examples and comparative examples, the structure and model number of the electrode assembly 10 are the same.

[0136] Comparative Example 1 Referring to Figure 28, no adhesive portion is provided on the surface of the electrode assembly. The electrode assembly is provided with a first insulating layer and a second insulating layer, and the first and second insulating layers are fixed to the electrode assembly by extending from the first surface through the second portion to the second surface, respectively. The case (aluminum laminate film) houses the electrode assembly and is fixed to the electrode assembly by the adhesive portion. After injecting the electrolyte and sealing the case, a battery is obtained. After performing a formation treatment on the battery, the battery capacity is activated by performing a standard charge and discharge process, and finally, the battery is degassed to complete the manufacturing process.

[0137] Comparative Example 2 Referring to Figure 29, the distinction 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, located on the side away from the second portion of the first insulating layer and the second insulating layer.

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

[0139] Example 2 Referring to Figure 31, the distinction between Example 2 and Example 1 is that the adhesive portion is further provided at the boundary between the first surface of the first insulating layer and the surface separating from it, the surface separating from the first surface of the first insulating layer, the boundary between the first surface of the second insulating layer and the surface separating from it, and the surface separating from the first surface of the second insulating layer.

[0140] Example 3 Referring to Figure 32, the distinction 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 Figure 33, the distinction between Example 4 and Comparative Example 1 is that the adhesive portion is provided only in the region located between the first insulating layer and the second insulating layer on the first surface of the electrode assembly.

[0142] At room temperature, the batteries of Comparative Examples 1-2 and Examples 1-4 are charged with a current of 0.2C, and the thickness of the batteries is measured after they are fully charged. Next, each of the above batteries is discharged to the cutoff voltage, and then charged with a constant current and constant voltage of 0.8C to the limiting voltage. After that, the thickness of each region of the battery is measured and set as the initial thickness (here, the thickness of the region in which the first insulating layer is provided in the battery is set as D1, or the thickness of the region in which the second insulating layer is provided in the battery is set as D2, and the thickness of the region between the first insulating layer and the second insulating layer of the battery is set as D3. Specifically, refer to Figure 34. Among these, the region measured for the battery of Comparative Example 1, which does not have the first and second insulating layers, corresponds to the region measured for the batteries of Comparative Examples / Examples that have the first and second insulating layers). The difference between D3 and D1 or the difference between D3 and D2, ΔD, is calculated and recorded in Table 1 below. Next, the battery is cycled 700 times using a 0.8C / 1C charge / discharge method, and after 700 cycles, the thickness of each region is measured again, i.e., the thickness after cycling, and the difference between D3 and D1 or the difference between D3 and D2 ΔD is calculated and recorded in Table 1 below.

[0143] [Table 1]

[0144] As can be seen from the data above, the provision of the first and second insulating layers can suppress battery swelling. After a charge-discharge cycle, the amount of deformation of a battery with an adhesive joint between the first and second insulating layers is clearly smaller than the amount of deformation of a battery without an adhesive joint between the first and second insulating layers. In the connection region of the electrode assembly, the two opposing surfaces connecting the first part (i.e., the head part) and the second part (i.e., the bottom part) 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 with a current of 0.2C at room temperature, a drop test is performed on the batteries. Specifically, the batteries are fixed to a battery-specific drop test box with a special adhesive, and a robotic arm grasps the drop test box with the batteries and drops it onto a marble slab from a height of 1.8m according to a predetermined drop pattern. The predetermined drop pattern consists of six drops each time, in the following order: 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) is observed to see if it is damaged, and the open-circuit voltage of the battery is measured. If the open-circuit voltage of a battery is less than 3.0V, the battery is determined to be dead. Similarly, if the aluminum laminate film on the surface of the battery is damaged, the battery is also determined to be dead. For each comparative example or example, five batteries are measured each time, the average value is taken, and the number of drops, cause of failure, and condition of the battery at the time of failure are recorded in Table 2.

[0145] [Table 2]

[0146] As can be seen from the data above, providing an adhesive portion in the region between the first insulating layer and the second insulating layer is advantageous in improving battery failure due to dropping compared to not providing an adhesive portion, and thereby is advantageous in improving battery safety. Furthermore, providing both the first insulating layer and the second insulating layer, along with the adhesive portion, can improve the battery failure situation due to dropping, and is advantageous in improving battery safety.

[0147] In the present invention, the battery has a first insulating layer and a second insulating layer on the surface of the electrode assembly, and a first adhesive portion is provided between the first insulating layer and the second insulating layer. When the electrode assembly is packaged in a case, the first adhesive portion adheres the electrode assembly to the case. When the battery is subjected to external forces, this is advantageous in reducing damage to the case of the electrode assembly, and at the same time, it is advantageous in protecting the electrode assembly itself, thereby improving the safety of the battery and extending its service life.

[0148] Furthermore, while those skilled in the art may make other corresponding changes and modifications based on the proposed technical idea and concept of the present invention, all such changes and modifications should 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, a second surface separated from the first surface in a third direction, a third end of the electrode assembly, and a fourth end of the electrode assembly located opposite the third end of the electrode assembly in a second direction perpendicular to the third direction, A first insulating layer is provided at the fourth end of the electrode assembly and extends from the first surface to the second surface, A battery including a first adhesive portion, In the electrode assembly, the metal portion extends from the third end of the electrode assembly. The first adhesive portion is provided on the first surface of the electrode assembly, and when viewed from a first direction, the first adhesive portion overlaps with the first insulating layer, and at least a portion of the first adhesive portion is spaced apart from the first insulating layer in the first direction, and the first direction is perpendicular to the second direction. The battery further includes the surface of the first insulating layer and a third adhesive portion provided continuously with the first surface, and the battery further includes a second adhesive portion provided on a surface of the first insulating layer that is separated from the second surface.

2. The battery according to claim 1, further comprising a second insulating layer provided at the fourth end of the electrode assembly, spaced apart from the first insulating layer in the first direction, and extending from the first surface to the second surface.

3. The battery according to claim 2, wherein the first adhesive portion is located between the first insulating layer and the second insulating layer in the first direction.

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

5. The battery according to claim 1, wherein the orthographic area of ​​the second adhesive portion on the first surface is smaller than the orthographic area of ​​the first insulating layer on the first surface.

6. The battery according to claim 1, wherein the first insulating layer comprises at least one of polyimide, polyvinyl chloride, polyethylene, and polypropylene.

7. The battery according to claim 1, wherein the first adhesive portion comprises at least one of cellulose, polyvinylidene-co-hexafluoropropylene, polyvinylidene-co-trichloroethylene, polymethyl methacrylate, butyl polyacrylate, polyacrylonitrile, polyvinylpyrrolidone, polyvinyl acetate, polyethylene-co-vinyl acetate, polyethylene oxide, polyarylate, cellulose acetate, cellulose acetate butyrate, cellulose acetate propionate, cyanoethyl pullulan, cyanoethyl polyvinyl alcohol, cyanoethylcellulose, cyanoethyl saccharose, pullulan, carboxymethylcellulose, and polypropylene-maleic anhydride.

8. The battery according to claim 2, wherein the orthographic area on the first surface of the first adhesive portion is smaller than the total orthographic area on the first surfaces of the first insulating layer and the second insulating layer.

9. The battery according to claim 8, wherein the orthographic area of ​​the first surface of the first adhesive portion is smaller than the orthographic area of ​​the first surface of the first insulating layer and smaller than the orthographic area of ​​the first surface of the second insulating layer.

10. The battery according to claim 2, wherein in the third direction, the distance from the part of the first surface where the first surface and the first insulating layer are in contact to the second surface is the first distance, the distance from the first adhesive portion to the second surface in the third direction is the second distance, the first distance is smaller than the second distance, and the third direction is the direction in which the first surface and the second surface are aligned.

11. The battery according to claim 10, wherein in the third direction, the distance from a portion of the first surface to the second surface where the first surface and the second insulating layer are in contact is a third distance, and the third distance is smaller than the second distance.

12. The battery according to 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.

13. The battery according to claim 1, wherein the first surface is provided with a first groove, and at least a portion of the first adhesive portion is located within the first groove.

14. The battery according to claim 13, wherein a second groove is provided on the surface of the first insulating layer, and at least a portion of the second adhesive portion is located within the second groove.

15. The battery according to claim 1, further comprising a plurality of fourth adhesive portions provided on the first surface and located between the third end and the fourth end of the electrode assembly.

16. The battery according to claim 15, wherein the electrode assembly includes at least two fourth bonding portions with different orthographic shapes.

17. The battery according to claim 15, wherein the electrode assembly includes at least two fourth adhesive portions, and the fourth adhesive portions are distributed in a dot matrix.

18. The electrode assembly has a wound structure, The electrode assembly further includes a third insulating layer, The battery according to claim 1, wherein the third insulating layer is provided on the second surface and fixes the end of the outermost electrode piece of the electrode assembly.

19. The battery according to claim 2, further comprising a case, the case enclosing the electrode assembly, the first insulating layer and the second insulating layer, and being bonded to the electrode assembly by a first adhesive portion.

20. The battery according to claim 1, further comprising two or more second adhesive portions provided on a surface of the first insulating layer that is separated from the second surface.

21. The battery according to claim 20, wherein the two or more second adhesive portions are distributed in a dot matrix.

22. The battery according to claim 1, further comprising two or more second adhesive portions provided on a surface of the first insulating layer that is separated from the second surface, wherein the orthographic projection area of ​​each of the two or more second adhesive portions on the first surface is smaller than the orthographic projection area of ​​the first surface of the first insulating layer.

23. The battery according to claim 1, further comprising two or more second adhesive portions provided on a surface away from the second surface of the first insulating layer, wherein the orthographic projection area of ​​the second adhesive portions on the first surface is smaller than the orthographic projection area of ​​the first surface of the first insulating layer.

24. The battery according to claim 1, wherein two or more second grooves are provided on the surface of the first insulating layer, and each of the second grooves is provided with the second adhesive portion.

25. The battery according to claim 2, further comprising two or more first adhesive portions provided on the first surface.

26. The battery according to claim 25, wherein, for each of the two or more first adhesive portions, the orthographic area of ​​the first adhesive portion on the first surface is smaller than the total orthographic area of ​​the first insulating layer and the second insulating layer on the first surface.

27. The battery according to claim 25, wherein the orthographic area on the first surface of the first adhesive portion is smaller than the total orthographic area on the first surfaces of the first insulating layer and the second insulating layer.

28. An electronic device comprising a battery as described in claim 1.

Images