Battery monomer, battery and electric device

Abstract

The utility model relates to the field of batteries, and provides a battery monomer, a battery and a power utilization device. Each battery monomer comprises a shell, a battery cell group and an insulating shell; the insulating shell comprises a substrate, a main folding sheet and a side folding sheet. The substrate supports the battery cell group. The two main folding pieces are arranged on the two opposite sides of the base piece in the first direction respectively. The insulating shell has a first side along the second direction. On the first side, at least one main folding piece is connected with a side folding piece through a transition angle, the side folding piece covers the corresponding side of the battery cell group, the transition angle is connected with the main folding piece through a first folding line and is connected with the side folding piece through a second folding line, and the substrate is connected with an extending folding piece through a third folding line; the third folding line is staggered with the straight line where the first folding line is located and / or staggered with the straight line where the second folding line is located when the insulating shell is unfolded, the extending folding piece is folded to the corresponding side of the battery cell group, and a gap between the folding piece on the corresponding side and the substrate is sealed and covered. Based on the structure, the insulation effect of the insulation shell between the battery cell group and the shell can be improved.

Description

Technical Field

[0001] The present application belongs to the field of battery technology, and in particular relates to a battery cell, a battery and an electrical device. Background Art

[0002] In some cases, a battery cell includes a shell, a battery cell group contained in the shell, and an insulating shell covering the outer surface of the battery cell group, and the insulating shell is used to insulate and isolate the battery cell group from the shell. However, there will be gaps at the joints of the insulating shell, which affects the insulation effect. Utility Model Content

[0003] The embodiments of the present application provide a battery cell, a battery and an electrical device, which aim to solve the problem that gaps may exist at the joints of an insulating shell, thereby affecting the insulation effect.

[0004] To achieve the above purpose, the technical solution adopted in the embodiment of the present application is:

[0005] In a first aspect, a battery cell is provided, the battery cell comprising:

[0006] shell;

[0007] A battery cell group is contained in the housing, and the battery cell group includes one or more electrode assemblies arranged side by side;

[0008] The insulating shell comprises a base sheet, a main folding sheet and a side folding sheet, wherein the base sheet supports the battery cell group, and two main folding sheets are provided and are respectively provided on two opposite sides of the base sheet along a first direction to respectively cover two opposite sides of the battery cell group along the first direction; the insulating shell has a first side along a second direction, and the second direction is perpendicular to the first direction;

[0009] On the first side: at least one main folding piece is connected to a side folding piece via a transition angle, the side folding piece covers the corresponding side of the battery cell group, the transition angle is connected to the main folding piece via a first fold line, and is connected to the side folding piece via a second fold line, the base sheet is connected to an extension folding piece via a third fold line, the third folding line is misaligned with the straight line where the first folding line is located in the unfolded state of the insulating shell, and / or is misaligned with the straight line where the second folding line is located, the extension folding piece is folded to the corresponding side of the battery cell group, and covers the gap between the corresponding side folding piece and the base sheet.

[0010] In the battery cell provided in the embodiment of the present application, the insulating shell can support the battery cell group through the substrate, and respectively cover the two opposite sides of the battery cell group along the first direction through two main folding pieces arranged on the opposite sides of the substrate along the first direction. On this basis, the insulating shell can also cover the corresponding side of the battery cell group on the first side through the side folding piece connected to at least one main folding piece, and fold to the corresponding side of the battery cell group through the extension folding piece connected to the substrate to cover the gap between the corresponding side folding piece and the substrate, so that at the gap between the corresponding side folding piece and the substrate, the extension folding piece can effectively insulate and isolate the battery cell group and the shell. Based on this, the insulating shell can be reliably covered on the outside of the battery cell group through the relatively comprehensive and reliable insulating shell, and the battery cell group and the shell can be reliably insulated and isolated, so that the insulating effect of the insulating shell between the battery cell group and the shell can be improved, the risk of the battery cell group contacting the shell through the seam gap of the insulating shell can be reduced, and the risk of the shell corrosion caused by the direct contact between the battery cell group and the shell can be reduced.

[0011] In addition, in this embodiment, on the first side, the third fold line is arranged to be offset from the straight line where at least one of the first fold line and the second fold line is located in the unfolded state of the insulating shell, so that the extension fold can be smoothly bent to the corresponding side of the battery cell group, and the risk of interference between the extension fold and the corresponding side fold can be reduced. In addition, when the extension fold is bent along the third fold line to the corresponding side of the battery cell group, the extension fold can be close to the corresponding side fold, thereby reducing the risk of a large gap between the extension fold and the corresponding side fold, optimizing the insulation effect of the side fold and the extension fold on the first side, and optimizing the insulation effect between the insulating shell and the battery cell group and the outer shell.

[0012] In some embodiments, the third fold line is between the straight line where the first fold line is located and the straight line where the second fold line is located when the insulating shell is in the unfolded state.

[0013] By adopting the above scheme, by making the third fold line between the straight line where the first fold line and the straight line where the second fold line are located in the unfolded state of the insulating shell, the extension fold can be smoothly and smoothly bent to the corresponding side of the battery cell group, and the risk of interference between the extension fold and the corresponding side fold can be reduced. In addition, when the extension fold is bent along the third fold line to the corresponding side of the battery cell group, the extension fold, especially the corner area between the extension fold and the base sheet, can be close to the corresponding side fold, thereby reducing the risk of gaps and gaps between the extension fold (especially the corner area between the extension fold and the base sheet) and the corresponding side fold, and optimizing the insulation effect of the side fold and the extension fold on the first side, and optimizing the insulation effect between the insulating shell and the battery cell group and the outer shell. This embodiment is particularly suitable for the situation where "the extension fold is folded to the outside of the corresponding side fold".

[0014] In some embodiments, the extension flaps are folded to the outside of the corresponding side flaps.

[0015] By adopting the above scheme, when the side folding piece, the main folding piece and the base sheet cooperate to cover the battery cell group, the extension folding piece can be folded to the outside of the corresponding side folding piece, so as to reliably cover the gap between the corresponding side folding piece and the base sheet through the extension folding piece. Based on this, the bending of the extension folding piece can be facilitated, especially the connection and fixation of the side folding piece and the extension folding piece can be facilitated, the covering effect of the extension folding piece on the gap between the side folding piece and the base sheet can be visually optimized, and the risk of the extension folding piece missing the covering gap can be reduced. As a result, the folding convenience of the insulating shell can be improved, the structural reliability and structural stability of the insulating shell in the covering state can be improved, the risk of the insulating shell falling apart can be reduced, and the insulation effect of the insulating shell between the battery cell group and the shell can be optimized. In addition, by folding the extension folding piece to the outside of the corresponding side folding piece, the side folding piece can be made to fit and cover the corresponding side of the battery cell group, thereby optimizing the insulation covering property of the side folding piece on the corresponding side of the battery cell group.

[0016] In some embodiments, on the first side, the two main folding sheets are connected to side folding sheets via transition angles, and the two side folding sheets jointly cover corresponding sides of the battery cell group.

[0017] By adopting the above scheme, in the wrapped state of the insulating shell, the first side can be bent to the same side of the battery cell group through the two side folding pieces respectively connected to the two main folding pieces, and jointly wrap the corresponding side of the battery cell group. Based on this, on the one hand, the convenience of bending the two side folding pieces towards each other and wrapping the same side of the battery cell group can be improved, thereby improving the folding convenience of the insulating shell and the assembly convenience of the insulating shell and the battery cell group. On the one hand, the connection gap between the two side folding pieces can be located in the middle of the corresponding side of the battery cell group, which can improve the connection strength between the two side folding pieces, balance the force of the two side folding pieces during the expansion of the battery cell group, reduce the risk of the two side folding pieces falling apart and being stretched, and enable the two side folding pieces to firmly and stably insulate and wrap the corresponding side of the battery cell group, thereby improving the insulation wrapping effect of the two side folding pieces on the corresponding side of the battery cell group, and optimizing the insulation effect of the insulating shell between the battery cell group and the outer shell.

[0018] In some embodiments, the extension flap is folded to the outside of the two side flaps.

[0019] By adopting the above scheme, on the first side, when the two side folding pieces jointly cover the corresponding side surfaces of the battery cell group, the extension folding piece can be folded to the outside of the two side folding pieces, so as to reliably cover the gap between the two side folding pieces and the base sheet through the extension folding piece. Based on this, the bending of the extension folding piece can be facilitated, especially the connection and fixation of the extension folding piece with the two side folding pieces, and the covering effect of the extension folding piece on the gap between the two side folding pieces and the base sheet can be visually optimized, and the risk of the extension folding piece missing the covering gap can be reduced. As a result, the folding convenience of the insulating shell can be improved, the structural reliability and structural stability of the insulating shell in the covering state can be improved, the risk of the insulating shell falling apart can be reduced, and the insulation effect of the insulating shell between the battery cell group and the shell can be optimized. In addition, by folding the extension folding piece to the outside of the two side folding pieces, the two side folding pieces can be enabled to reliably, comprehensively and fitly cover the corresponding side surfaces of the battery cell group, thereby optimizing the insulation covering effect of the two side folding pieces on the corresponding side surfaces of the battery cell group.

[0020] In some embodiments, on the first side, the two side flaps are respectively a first side flap and a second side flap, and a portion of the first side flap is folded to the outside of the second side flap.

[0021] By adopting the above scheme, in the wrapped state of the insulating shell, the first side can cover the corresponding side of the battery cell group through the first side folding piece and the second side folding piece that overlap in the projection along the second direction. Based on this, the first side folding piece can be caused to form a pressing effect on the second side folding piece through the part that is folded to the outside of the second side folding piece, thereby enhancing the connection strength between the first side folding piece and the second side folding piece, which can be beneficial to maintaining the shape of the first side folding piece and the second side folding piece during the expansion of the battery cell group, and can reduce the risk of the first side folding piece and the second side folding piece falling apart and being stretched apart, and can enable the first side folding piece and the second side folding piece to reliably, durably and comprehensively insulate and cover the corresponding side of the battery cell group, thereby optimizing the insulation covering effect of the first side folding piece and the second side folding piece on the corresponding side of the battery cell group, and optimizing the insulation effect of the insulating shell between the battery cell group and the outer shell. Moreover, when in the wrapped state of the insulating shell, even if there are processing errors in the dimensions of the battery cell group, the first side fold piece and the second side fold piece along the first direction, due to the overlapping part of the first side fold piece and the second side fold piece, the first side fold piece and the second side fold piece can be compatible with dimensional deviations within a certain range, and can still fully insulate and wrap the corresponding sides of the battery cell group, thereby improving the dimensional compatibility, applicability and reliability of the insulating shell.

[0022] In some embodiments, a portion of the first side flap folded to the outside of the second side flap is provided with a first notch.

[0023] By adopting the above scheme, in the wrapped state of the insulating shell, on the first side, the part of the first side folded to the outside of the second side folded can pass through the first notch to expose the corresponding area of ​​the second side folded, so that the adhesive structure (such as tape) passes through the first notch to reliably and firmly adhere and fix the first side folded sheet and the second side folded sheet. Based on this, the connection convenience, connection reliability and connection strength between the first side folded sheet and the second side folded sheet can be improved, the risk of the first side folded sheet and the second side folded sheet falling apart can be reduced, and the first side folded sheet and the second side folded sheet can be enabled to reliably and durably insulate and wrap the corresponding side of the battery cell group, thereby optimizing the insulation wrapping effect of the first side folded sheet and the second side folded sheet on the corresponding side of the battery cell group, and optimizing the insulation effect of the insulating shell between the battery cell group and the outer shell.

[0024] In some embodiments, the extension fold is folded to the outside of the first side fold and the second side fold, or the extension fold is folded between the first side fold and the second side fold; the first notch is provided at one end of the first side fold close to the extension fold, and a portion of the first notch is exposed outside the extension fold.

[0025] By adopting the above scheme, when the extension flap is folded outside the first side flap, or when the extension flap is folded between the first side flap and the second side flap, the first notch can be provided at one end of the first side flap close to the extension flap, and a part of the first notch can be exposed outside the extension flap, so that the part exposed outside the extension flap in the first notch can expose the corresponding area of ​​the second side flap. Based on this, near the first notch, the first side flap, the second side flap, and the extension flap all have exposed parts, so that it is convenient for the adhesive structure (such as an adhesive tape) to pass through the first notch, and reliably and firmly adhere and fix the first side flap, the second side flap, and the extension flap. In this way, the connection convenience, connection reliability and connection strength of the first side fold sheet, the second side fold sheet and the extension fold sheet can be improved, the risk of the first side fold sheet, the second side fold sheet and the extension fold sheet falling apart can be reduced, and the first side fold sheet, the second side fold sheet and the extension fold sheet can be enabled to reliably and durably insulate and wrap the corresponding sides of the battery cell group, thereby optimizing the insulation wrapping effect of the first side fold sheet, the second side fold sheet and the extension fold sheet, and optimizing the insulation effect of the insulation shell.

[0026] In some embodiments, the first notch is disposed at a corner of the first side flap close to the extension flap.

[0027] By adopting the above solution, by processing the first notch at the corner of the first side flap close to the extension flap, it is convenient to form the first notch by cutting or cutting, which is convenient for processing the first notch and can facilitate the precise control of the size of the first notch. In addition, since the first notch is set at the corner, the effect of processing the first notch on the structural strength of the first side flap can be reduced, the risk of cracking and fissures in the first side flap near the first notch can be reduced, and the insulation coverage and service life of the first side flap can be maintained.

[0028] In some embodiments, along a direction perpendicular to the third fold line, a dimension of the extended flap ranges from 5 mm to 15 mm.

[0029] By adopting the above scheme, the size range of the extended folding piece is made 5mm to 15mm along the direction perpendicular to the third fold line, so that when the extended folding piece is folded to the corresponding side of the battery cell group, the gap between the corresponding side folding piece and the base sheet can be reliably covered, and the size of the extended folding piece can also be correspondingly constrained to reduce the amount of consumables of the adhesive structure (such as tape) used to fix the extended folding piece, and reduce the risk of warping of the extended folding piece after fixation.

[0030] In some embodiments, a second gap is provided between the extension flap and the side flap adjacent thereto.

[0031] By adopting the above solution, by providing a second notch between the extension flap and the side flap adjacent thereto, the pulling effect of the extension flap on the adjacent side flap can be reduced during the period when the extension flap is folded to the corresponding side of the battery cell group, thereby optimizing the folding convenience and folding quality of the insulating shell, and improving the flatness and accuracy of the folding of the extension flap and the side flap. In addition, the provision of the second notch also helps to reduce the stress concentration in the area adjacent to the side flap and the extension flap, thereby reducing the risk of deformation or rupture in the area adjacent to the side flap and the extension flap, and optimizing the structural strength and service life of the side flap.

[0032] In some embodiments, at least one corner of the substrate is rounded.

[0033] By adopting the above scheme, by making at least one corner of the substrate rounded, the risk of interference between the substrate of the insulating shell and the bottom surface of the cell group can be reduced during the assembly of the battery cell group and the insulating shell, and the risk of interference between the corner of the substrate of the insulating shell and the outer shell can be reduced during the assembly of the insulating shell and the outer shell, thereby improving the convenience of assembling the insulating shell with the battery cell group and the outer shell, reducing the risk of damage to the corner of the insulating shell due to friction, impact, shock, etc. during assembly, reducing the risk of damage to the insulating shell during assembly, and improving the performance and service life of the insulating shell.

[0034] In some embodiments, the corners of the base sheet disposed adjacent to the extension flap are rounded;

[0035] Along the first direction, the width of the extension flap is equal to the width of the base sheet minus the dimensions of two corners of the base sheet adjacent to the extension flap.

[0036] By adopting the above solution, along the first direction, the width of the extension flap is made equal to: the width of the base minus the size of one of the corners of the base adjacent to the extension flap, minus the size of the other corner of the base adjacent to the extension flap; the extension flap can completely cover the gap between the corresponding edge of the base and the corresponding side flap. Based on this, the covering effect of the extension flap on the gap between the side flap and the base can be optimized, and the risk of the extension flap missing the covering gap can be reduced, so that the insulation effect of the side flap and the extension flap on the first side can be optimized, and the insulation effect between the insulating shell and the battery cell group and the outer shell can be optimized.

[0037] In some embodiments, the extension flap, the corner of the base sheet adjacent thereto, and the side flap adjacent thereto form a second gap.

[0038] By adopting the above scheme, on the basis of the previous embodiment, the second notch can be formed by the extension flap, the corner of the substrate arranged adjacent to the extension flap, and the side flap arranged adjacent to the extension flap. Based on this, the pulling effect of the extension flap on the adjacent side flap can be reduced during the period when the extension flap is folded to the corresponding side of the battery cell group, thereby optimizing the folding convenience and folding quality of the insulating shell, and improving the flatness and accuracy of the folding of the extension flap and the side flap. In addition, the second notch can be formed by enclosing the size of the extension flap, the corner of the substrate, and the side flap, without the need to form it by cutting the material, thereby improving the convenience of forming the second notch and optimizing the overall structure of the insulating shell. In addition, the setting of the second notch also helps to reduce the stress concentration in the adjacent areas of the side flap, the corner of the substrate and the extension flap, thereby reducing the risk of deformation or rupture of the adjacent areas of the side flap, the corner of the substrate and the extension flap, and optimizing the structural strength and service life of the insulating shell.

[0039] In some embodiments, the first fold line is spaced apart from a corresponding side of the main flap at at least one end of the first fold line in its extension direction.

[0040] By adopting the above solution, by setting the first fold line at least one end in its extension direction at a distance from the corresponding side of the main fold piece, the first fold line can be made not to penetrate the main fold piece in its extension direction. Based on this, the main fold piece and the transition angle can have a stronger connection strength in the area where the first fold line does not extend, and the connection strength, connection reliability and durability between the main fold piece and the transition angle can be maintained and improved, and the risk of cracks, splits and tears in the connection area between the main fold piece and the transition angle can be reduced, thereby improving the structural reliability and service life of the insulation shell.

[0041] In some embodiments, the second fold line is spaced apart from the corresponding side of the side flap at at least one end of the second fold line in its extension direction.

[0042] By adopting the above solution, by setting the second fold line at least one end in its extension direction at a distance from the corresponding side of the side fold piece, the second fold line can be made not to penetrate the side fold piece in its extension direction. Based on this, the connection strength between the side fold piece and the transition corner can be stronger in the area where the second fold line does not extend, the connection strength, connection reliability and durability between the side fold piece and the transition corner can be maintained and improved, and the risk of cracks, splits and tears in the connection area between the side fold piece and the transition corner can be reduced, thereby improving the structural reliability and service life of the insulation shell.

[0043] In some embodiments, the third fold line is spaced apart from a corresponding side of the extension flap at at least one end of the third fold line in its extension direction.

[0044] By adopting the above solution, by setting at least one end of the third fold line in its extension direction at a distance from the corresponding side of the extension folded piece, the third fold line can be made not to penetrate the extension folded piece in its extension direction. Based on this, the connection strength between the extension folded piece and the base sheet in the area where the third fold line is not extended can be stronger, the connection strength, connection reliability and durability between the extension folded piece and the base sheet can be maintained and improved, and the risk of cracks, splits and tears in the connection area between the extension folded piece and the base sheet can be reduced, thereby improving the structural reliability and service life of the insulating shell.

[0045] In some embodiments, the extension flap is a rectangular structure.

[0046] By adopting the above solution, by making the extension flap a rectangular structure, the shape of the extension flap can be regularized, the extension flap can have a regular and large surface area, can cover a wider area, can reliably cover the gap between the corresponding side flap and the base sheet, thereby optimizing the covering effect of the extension flap on the gap between the side flap and the base sheet, and reducing the risk of the extension flap missing the covering gap. In addition, the rectangular extension flap is easy to process, fold and install.

[0047] In some embodiments, the transition corners are rounded.

[0048] By adopting the above scheme, by making the transition angle rounded, the connected main folding piece and the side folding piece can be connected by a rounded transition. Based on this, the stress concentration between the connected main folding piece and the side folding piece can be reduced, and the stress can be evenly distributed in the transition area between the connected main folding piece and the side folding piece, thereby improving the connection strength and connection reliability between the connected main folding piece and the side folding piece, reducing the risk of cracks and cracks in the connection area between the main folding piece and the side folding piece, and optimizing the structural strength and service life of the insulating shell. In addition, during the assembly of the battery cell group and the insulating shell, the rounded transition angle can reduce the risk of interference between the edges of the insulating shell and the battery cell group, during the assembly of the insulating shell and the outer shell, the rounded transition angle can reduce the risk of interference between the edges of the insulating shell and the outer shell, thereby reducing the risk of damage to the edges of the insulating shell due to friction, impact, shock, etc. during assembly, reducing the risk of damage to the insulating shell during assembly, improving the convenience of assembly of the insulating shell with the battery cell group and the outer shell, and improving the performance and service life of the insulating shell.

[0049] In a second aspect, a battery is provided, the battery comprising the battery cell provided in the embodiment of the present application.

[0050] By adopting the above solution, the battery can improve the reliability and service life of each battery cell by applying the battery cell provided by the embodiment of the present application, thereby improving the reliability and service life of the battery.

[0051] In a third aspect, an electrical device is provided, which includes the battery provided in an embodiment of the present application, or the battery cell provided in an embodiment of the present application.

[0052] By adopting the above solution, the electrical device can improve the reliability and service life of the electrical device by applying the battery or battery cell provided in the embodiment of the present application. BRIEF DESCRIPTION OF THE DRAWINGS

[0053] In order to clearly illustrate the technical solutions in the embodiments of the present application, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0054] Figure 1 A schematic diagram of the structure of a vehicle provided in some embodiments of the present application;

[0055] Figure 2 An exploded schematic diagram of a battery provided in some embodiments of the present application;

[0056] Figure 3 An exploded schematic diagram of a battery cell provided in some embodiments of the present application;

[0057] Figure 4 A schematic diagram of the structure of an insulating shell in an expanded state provided in some embodiments of the present application;

[0058] Figure 5 A schematic diagram of the structure of the insulating housing provided in some embodiments of the present application when the extended flap is not folded;

[0059] Figure 6 A schematic diagram of the structure of an insulating shell in a finished product state provided in some embodiments of the present application;

[0060] Figure 7 for Figure 6 A magnified image of region A is provided;

[0061] Figure 8 for Figure 4 A magnified image of region B is provided.

[0062] Among them, the reference numerals in the figure are:

[0063] 1-battery, 2-controller, 3-motor; 100-battery unit, 200-box, 201-first part, 202-second part;

[0064] 10-battery cell, 11-housing, 111-housing, 112-end cover; 12-cell group, 121-electrode assembly, 1211-electrode body, 1212-ear, 1212a-positive electrode ear, 1212b-negative electrode ear; 13-insulating shell, 131-substrate, 132-main folding sheet, 1321-fourth folding line, 133-side folding sheet, 133a-first side folding sheet, 1331-first notch, 133b-second side folding sheet, 134-extension folding sheet, 1341-third folding line, 1342-second notch, 135-first side, 136-transition angle, 1361 -first fold line, 1362-second fold line, 14-insulating member; 15-electrode terminal, 15a-positive electrode terminal, 15b-negative electrode terminal; 16-converter, 16a-positive electrode converter, 16b-negative electrode converter; 17-explosion-proof valve; a-first direction, b-second direction, d1-dimension of the extended fold along the direction perpendicular to the third fold line, d2-width of the extended fold along the first direction, d3-width of the substrate along the first direction, d4-dimension of one of the corners of the substrate adjacent to the extended fold along the first direction, d5-dimension of the other corner of the substrate adjacent to the extended fold along the first direction. DETAILED DESCRIPTION

[0065] In order to make the technical problems, technical solutions and beneficial effects to be solved by this application clear and understandable, the application is described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described here are only used to explain this application and are not used to limit this application.

[0066] In the description of the present application, it should be understood that the terms "length", "width", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", etc., indicating the orientation or position relationship, are based on the orientation or position relationship shown in the accompanying drawings, and are only for the convenience of describing the present application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the present application.

[0067] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Therefore, a feature defined as "first" or "second" may explicitly or implicitly include one or more of the features. In the description of this application, the meaning of "plurality" is two or more, unless otherwise clearly and specifically defined.

[0068] In this application, unless otherwise clearly specified and limited, the terms "installed", "connected", "connected", "fixed" and the like should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements. For ordinary technicians in this field, the specific meanings of the above terms in this application can be understood according to specific circumstances.

[0069] A battery cell is the smallest unit for storing and outputting electrical energy. In some cases, a battery cell includes a housing, a battery cell group contained in the housing, and an insulating shell covering the outer surface of the battery cell group. The insulating shell is used to insulate and isolate the battery cell group from the housing. However, there is a gap at the joint between the circumferential side and the bottom of the insulating shell, which makes it easy for the battery cell group to contact the housing at the gap, causing the housing to corrode, thereby affecting the insulation effect of the insulating shell between the battery cell group and the housing.

[0070] Thus, the embodiment of the present application provides a battery cell, the insulating shell of which can support the battery cell group through the substrate, and respectively cover the opposite sides of the battery cell group along the first direction through two main folding pieces arranged on the opposite sides of the substrate along the first direction. On this basis, the insulating shell can also cover the corresponding side of the battery cell group on the first side through the side folding piece connected to at least one main folding piece, and fold to the corresponding side of the battery cell group through the extension folding piece connected to the substrate to cover the gap between the corresponding side folding piece and the substrate, so that at the gap between the corresponding side folding piece and the substrate, the extension folding piece can effectively insulate and isolate the battery cell group and the shell. Based on this, the insulating shell can be reliably covered on the outside of the battery cell group through the relatively comprehensive and reliable insulating shell, and the battery cell group and the shell can be reliably insulated and isolated, so that the insulating effect of the insulating shell between the battery cell group and the shell can be improved, the risk of the battery cell group contacting the shell through the seam gap of the insulating shell can be reduced, and the risk of the shell corrosion caused by the direct contact between the battery cell group and the shell can be reduced.

[0071] Furthermore, in the embodiment of the present application, on the first side, the third fold line is arranged to be offset from the straight line where at least one of the first fold line and the second fold line is located in the unfolded state of the insulating shell, so that the extension fold can be smoothly bent to the corresponding side of the battery cell group, and the risk of interference between the extension fold and the corresponding side fold can be reduced. Furthermore, when the extension fold is bent along the third fold line to the corresponding side of the battery cell group, the extension fold can be close to the corresponding side fold, thereby reducing the risk of a large gap between the extension fold and the corresponding side fold, optimizing the insulation effect of the side fold and the extension fold on the first side, and optimizing the insulation effect between the insulating shell and the battery cell group and the outer shell.

[0072] The battery cell disclosed in the embodiment of the present application can be a lithium-ion secondary battery, a lithium-sulfur battery, a sodium-lithium-ion battery, a sodium-ion battery or a magnesium-ion battery, etc. The battery cell can be cylindrical, flat, rectangular or other shapes, etc. The battery cell can be packaged in different ways to form a cylindrical battery cell, a square battery cell or a soft-pack battery cell, etc.

[0073] The battery cells disclosed in the embodiments of the present application can be used independently or in combination with other battery cells to form a modular battery that can provide higher voltage and capacity, such as a battery module, a battery module or a battery pack.

[0074] The battery cells and batteries disclosed in the embodiments of the present application can be used in electrical devices that use battery cells and batteries as power sources, or in various energy storage systems that use battery cells and batteries as energy storage elements. The electrical device may be, but is not limited to, a vehicle, a mobile phone, a portable device, a laptop computer, a ship, a spacecraft, an electric toy, an electric tool, and the like. The vehicle may be a fuel vehicle, a gas vehicle, or a new energy vehicle, and the new energy vehicle may be a pure electric vehicle, a hybrid vehicle, or an extended-range vehicle, and the like. Spacecraft include airplanes, rockets, space shuttles, and spacecraft, and the like. Electric toys include fixed or mobile electric toys, such as game consoles, electric car toys, electric ship toys, and electric airplane toys, and the like. Electric tools include metal cutting electric tools, grinding electric tools, assembly electric tools, and railway electric tools, such as electric drills, electric grinders, electric wrenches, electric screwdrivers, electric hammers, impact drills, concrete vibrators, and electric planers, and the like.

[0075] In order to illustrate the technical solution provided by the present application, the following is a detailed description with reference to specific drawings and embodiments, and taking "the electrical device being a vehicle" as an example.

[0076] See also Figure 1 , Figure 1 A schematic diagram of the structure of a vehicle provided for some embodiments of the present application. The vehicle may be a fuel vehicle, a gas vehicle or a new energy vehicle, and the new energy vehicle may be a pure electric vehicle, a hybrid vehicle or an extended-range vehicle, etc. A battery 1 is provided inside the vehicle, and the battery 1 may be provided at the bottom, head or tail of the vehicle. The battery 1 is used to power the vehicle, for example, the battery 1 can be used as an operating power source for the vehicle. The vehicle may also include a controller 2 and a motor 3, and the controller 2 is used to control the battery 1 to power the motor 3, for example, for starting, navigating and driving the vehicle. Working power requirements.

[0077] In some embodiments of the present application, the battery 1 can be used not only as an operating power source for the vehicle, but also as a driving power source for the vehicle, replacing or partially replacing fuel or natural gas to provide driving power for the vehicle.

[0078] See also Figure 2 , Figure 2 The exploded schematic diagram of the battery 1 provided in some embodiments of the present application. The battery 1 comprises a battery cell 100 and a box body 200 , wherein the battery cell 100 is accommodated in the box body 200 .

[0079] The box body 200 is used to provide a storage space for components such as the battery cell 100. The box body 200 can provide dustproof, waterproof and protective protection for the battery cell 100 and other components contained therein, and can reduce the impact of external liquids or other foreign matter on the effectiveness and performance of the battery cell 100 and other components, and can effectively extend the service life of the battery 1.

[0080] Among them, the box body 200 can adopt a variety of structures. In some embodiments, the box body 200 may include a first part 201 and a second part 202, the first part 201 and the second part 202 cover each other, and the first part 201 and the second part 202 jointly define a storage space for accommodating the battery unit 100. The second part 202 may be a hollow structure with one end open, and the first part 201 may be a plate-like structure, and the first part 201 covers the open side of the second part 202, so that the first part 201 and the second part 202 jointly define a storage space; the first part 201 and the second part 202 may also be hollow structures with one side open, and the open side of the first part 201 covers the open side of the second part 202.

[0081] The box body 200 may be in various shapes, such as a cylinder, a cuboid, etc.

[0082] The box body 200 may be made of a variety of materials, such as copper, iron, aluminum, stainless steel, aluminum alloy, plastic, etc.

[0083] The battery cell 100 is an energy storage unit that can convert chemical energy into electrical energy. In the battery 1, one battery cell 100 can be provided, or at least two battery cells 100 can be provided. In the case where at least two battery cells 100 are provided, the at least two battery cells 100 can be connected in series, in parallel, or in mixed connection. Mixed connection means that at least two battery cells 100 are connected in series and in parallel.

[0084] The battery unit 100 may be a battery cell 10 (eg Figure 3 As shown). At least two battery cells 10 can be directly connected in series, in parallel or in mixed connection, and then the whole formed by at least two battery cells 10 is accommodated in the box body 200. Among them, the battery cell 10 can be a lithium-ion secondary battery, a lithium-sulfur battery, a sodium-lithium-ion battery, a sodium-ion battery or a magnesium-ion battery, etc. The battery cell 10 can be cylindrical, flat, rectangular or other shapes, etc. The battery cell 10 can be packaged in different ways to form a cylindrical battery cell, a square battery cell or a soft-pack battery cell, etc.

[0085] Alternatively, the battery unit 100 may be a battery module or a battery module. At least two battery cells 10 may be connected in series, in parallel, or in a hybrid connection to form a modular structure, i.e., a battery module or a battery module; at least two battery modules or battery modules may then be connected in series, in parallel, or in a hybrid connection to form a whole, and accommodated in the box 200.

[0086] Of course, the battery 1 may also include other structures, for example, the battery 1 may also include a busbar component (not shown in the figure) for realizing electrical connection between at least two battery cells 100. For another example, the battery 1 may also include a power distribution device (not shown in the figure) for serving as a control unit for distributing energy of the battery 1 and distributing high voltage to the battery 1.

[0087] Of course, in some embodiments, the battery 1 may not include the box body 200, but at least two battery cells 10 are electrically connected and formed into a whole through necessary fixing structures and then assembled into an electrical device.

[0088] See also Figure 3 , Figure 3 Schematic diagram of an exploded view of a battery cell 10 provided in some embodiments of the present application. The battery cell 10 is the smallest unit for storing and outputting electric energy. The battery cell 10 includes a housing 11, a battery cell group 12, an insulating shell 13, an insulating member 14, an electrode terminal 15, an adapter 16, an explosion-proof valve 17, an electrolyte (not shown in the figure), and other components.

[0089] The outer shell 11 is a component that isolates the internal environment of the battery cell 10 from the external environment. The outer shell 11 may include a shell 111 and an end cover 112. The end cover 112 is a component that covers the opening of the shell 111 to isolate the internal environment of the battery cell 10 from the external environment. In some embodiments, the shape of the end cover 112 can be adapted to the shape of the shell 111 to match the shell 111. In some embodiments, the end cover 112 can be made of a material with a certain hardness and strength, so that the end cover 112 is not easily deformed when squeezed and collided, so that the battery cell 10 can have a higher structural strength and the reliability performance can also be improved. Among them, the material of the end cover 112 can be diversified, and the end cover 112 can be made of copper, iron, aluminum, stainless steel, aluminum alloy, plastic and other materials.

[0090] The shell 111 is a component used to cooperate with the end cover 112 to form the internal environment of the battery cell 10. The internal environment formed by the shell 111 and the end cover 112 can be used to accommodate components such as the battery cell group 12, the insulating shell 13, the insulating member 14, and the electrolyte. In some embodiments, the shell 111 and the end cover 112 can be independent components, and an opening can be set on the shell 111, and the end cover 112 is covered at the opening to form the internal environment of the battery cell 10. In some embodiments, the end cover 112 and the shell 111 can also be integrated. Specifically, the end cover 112 and the shell 111 can form a common connection surface before other components are put into the shell. When it is necessary to encapsulate the interior of the shell 111, the end cover 112 is covered with the shell 111. Among them, the shell 111 can be of various shapes and sizes, such as a cuboid, a cylinder, a hexagonal prism, etc. The shape of the shell 111 can be determined according to the shape and size of the battery cell group 12. The material of the housing 111 can be varied, and the housing 111 can be made of copper, iron, aluminum, stainless steel, aluminum alloy, plastic, and other materials.

[0091] The battery cell group 12 is a component in the battery cell 10 where an electrochemical reaction occurs. The battery cell group 12 may include one or at least two electrode assemblies 121. In the case where multiple electrode assemblies 121 are provided, multiple electrode assemblies 121 may be arranged side by side. The electrode assembly 121 includes a positive electrode sheet (not shown in the figure), a negative electrode sheet (not shown in the figure) and a separator (not shown in the figure), and the separator separates the positive electrode sheet from the negative electrode sheet. The positive electrode sheet, the separator and the negative electrode sheet can be processed to form the electrode assembly 121 by winding, stacking or other methods. In the electrode assembly 121, the parts of the positive electrode sheet and the negative electrode sheet with active materials constitute the electrode body 1211 of the electrode assembly 121, and the parts of the positive electrode sheet and the negative electrode sheet without active materials each constitute the pole ear 1212, which is the current transmission end of the electrode assembly 121 for transmitting current. The tab 1212 of the positive electrode sheet is the positive electrode tab 1212a, and the tab 1212 of the negative electrode sheet is the negative electrode tab 1212b. The positive electrode tab 1212a and the negative electrode tab 1212b can be located together at one end of the electrode body 1211 or respectively at both ends of the electrode body 1211.

[0092] The insulating shell 13 is a shell-like structure with an open top and insulating properties. The insulating shell 13 is coated on the outside of the battery cell group 12, especially on the part of the battery cell group 12 except the top (i.e., it coats the circumferential side and bottom of the battery cell group 12). The insulating shell 13 is made of insulating material and has insulating properties. The insulating shell 13 is used to insulate and isolate the battery cell group 12 and the outer shell 11 to reduce the risk of outer shell corrosion caused by direct contact between the battery cell group 12 and the outer shell 11. Among them, the insulating shell 13 can be made of inorganic insulating materials, such as silicon oxide, silicon nitride, aluminum oxide, aluminum nitride, etc. The insulating shell 13 can also be made of organic insulating materials, such as polyimide, polyethylene, polyvinylidene fluoride, polytetrafluoroethylene, etc.

[0093] The electrolyte is the liquid that soaks the electrode assembly 121. The battery cell 10 mainly relies on the movement of active ions between the positive electrode plate and the negative electrode plate to work. When the battery cell 10 is charged, the positive electrode plate will generate active ions, and the active ions provided by the positive electrode plate can penetrate the pores of the diaphragm, move to the negative electrode plate via the electrolyte, and be embedded in the negative active material of the negative electrode plate. Conversely, when the battery cell 10 is discharged, the active ions embedded in the negative active material of the negative electrode plate escape, and the active ions escaped from the negative electrode plate can penetrate the pores of the diaphragm, move to the positive electrode plate via the electrolyte, and be embedded in the positive active material of the positive electrode plate. Among them, the active ions can be lithium ions, sodium ions, etc.

[0094] The electrode terminal 15 is a component electrically connected to the electrode assembly 121 and used to output or input electrical energy. The electrode terminal 15 includes a positive electrode terminal 15a and a negative electrode terminal 15b. The positive electrode terminal 15a is electrically connected to the positive electrode tab 1212a of the electrode assembly 121. The negative electrode terminal 15b is electrically connected to the negative electrode tab 1212b of the electrode assembly 121. The electrode terminal 15 can be installed in the housing 11 and stabilize the installation position and installation state relative to the housing 11. In some embodiments, the electrode terminal 15 can be installed in the housing 11 by flanging and riveting.

[0095] The adapter 16 is a current collecting member electrically connected between the pole ear 1212 of the electrode assembly 121 and the corresponding electrode terminal 15. The adapter 16 may also be referred to as an adapter connector, a current collecting plate or an adapter sheet, etc. The adapter 16 has a conductive property and is made of a conductive material. The material of the adapter 16 may include aluminum, aluminum alloy, copper, copper alloy, copper-aluminum alloy, etc. The adapter 16 includes a positive electrode adapter 16a and a negative electrode adapter 16b. The positive pole ear 1212a of the electrode assembly 121 can be electrically connected to the positive electrode terminal 15a through the positive electrode adapter 16a, and the negative pole ear 1212b of the electrode assembly 121 can be electrically connected to the negative electrode terminal 15b through the negative electrode adapter 16b to form a current loop. In some embodiments, the adapter 16 can be connected to the pole ear 1212 of the electrode assembly 121 by welding, abutment, etc. The adapter 16 can be connected to the electrode terminal 15 by welding, abutment, etc. The shape of the adapter 16 can be various, such as square, round, special-shaped, etc.

[0096] The insulating member 14 is a component with insulating properties. The insulating member 14 is arranged in the housing 11, especially between the electrode assembly 121 and the wall portion of the housing 11 having the electrode terminal 15 (such as the end cap 112). On the basis that the pole ear 1212 of the electrode assembly 121 and the corresponding electrode terminal 15 can be electrically connected, the insulating member 14 can be used to insulate and isolate the electrode assembly 121 and the wall portion of the housing 11 having the electrode terminal 15 to reduce the risk of short circuit, current leakage and the like. In addition, the insulating member 14 can also be fixed to the wall portion of the housing 11 having the electrode terminal 15, and abut the electrode assembly 121 to fill the gap between the electrode assembly 121 and the wall portion of the housing 11, and tightly fix the electrode assembly 121, so as to ensure to a certain extent that the electrode assembly 121 will not move or shake relatively during the use of the battery cell 10, which can be beneficial to maintain the structural integrity of the battery cell 10 and reduce the risk of loosening or deformation of the electrode assembly 121.

[0097] In some embodiments, an explosion-proof valve 17 may also be provided on the housing 11, and the explosion-proof valve 17 may be used to release the internal pressure when the internal pressure (or temperature) of the battery cell 10 reaches a threshold value. Correspondingly, an opening (not shown in the figure) is provided at the position of the insulating member 14 corresponding to the explosion-proof valve 17, and the opening is connected to the side of the insulating member 14 close to the electrode assembly 121 and the side of the insulating member 14 close to the explosion-proof valve 17, so as to allow at least part of the gas to flow from the opening to the explosion-proof valve 17 and be discharged through the explosion-proof valve 17 when the internal pressure (or temperature) of the battery cell 10 reaches a threshold value.

[0098] See also Figure 3 , Figure 4 , Figure 5 , Figure 6Some embodiments of the present application provide a battery cell 10, which includes an outer shell 11, a battery cell group 12, and an insulating shell 13. The battery cell group 12 is accommodated in the outer shell 11. The battery cell group 12 includes one or more electrode assemblies 121 arranged side by side. The insulating shell 13 includes a substrate 131, a main folding sheet 132, and a side folding sheet 133. The substrate 131 supports the battery cell group 12. Two main folding sheets 132 are provided, and are respectively arranged on opposite sides of the substrate 131 along the first direction a to respectively cover the opposite sides of the battery cell group 12 along the first direction a. The insulating shell 13 has a first side 135 along the second direction b, and the second direction b is perpendicular to the first direction a.

[0099] On the first side 135: at least one main folding piece 132 is connected to the side folding piece 133 via a transition angle 136, the side folding piece 133 covers the corresponding side of the battery cell group 12, the transition angle 136 is connected to the main folding piece 132 through a first fold line 1361, and is connected to the side folding piece 133 through a second fold line 1362, the base sheet 131 is connected to the extension folding piece 134 via a third fold line 1341, the third fold line 1341 is misaligned with the straight line where the first fold line 1361 is located in the unfolded state of the insulating shell 13, and / or is misaligned with the straight line where the second fold line 1362 is located, the extension folding piece 134 is folded to the corresponding side of the battery cell group 12, and covers the gap between the corresponding side folding piece 133 and the base sheet 131.

[0100] It should be noted that the housing 11 is a component that isolates the internal environment of the battery cell 10 from the external environment. In addition, other related descriptions of the housing 11 can be found in the above text, and will not be repeated here.

[0101] The cell group 12 is a component in the battery cell 10 where an electrochemical reaction occurs. The cell group 12 may include one or at least two electrode assemblies 121. In the case where there are multiple electrode assemblies 121, the multiple electrode assemblies 121 may be arranged side by side. The cell group 12 may be accommodated in the housing 11. In addition, other related descriptions of the cell group 12 can be referred to above, and will not be repeated here.

[0102] It should also be noted that the insulating shell 13 can be folded to change from the unfolded state to the wrapped state. The insulating shell 13 is in a wrapped state in the battery cell 10. In the wrapped state, the insulating shell 13 can form a shell-like structure that matches the shape of the battery cell group 12. The top of the insulating shell 13 is open, and the insulating shell 13 can be wrapped around the outside of the battery cell group 12, especially the outside of the battery cell group 12 except the top (that is, the circumferential side and bottom of the battery cell group 12).

[0103] The insulating shell 13 is made of insulating material and has insulating properties. The insulating shell 13 is used to insulate and isolate the battery cell group 12 and the outer shell 11 to reduce the risk of corrosion of the outer shell 11 caused by direct contact between the battery cell group 12 and the outer shell 11. Among them, the insulating shell 13 can be made of inorganic insulating materials, such as silicon oxide, silicon nitride, aluminum oxide, aluminum nitride, etc. The insulating shell 13 can also be made of organic insulating materials, such as polyimide, polyethylene, polyvinylidene fluoride, polytetrafluoroethylene, etc.

[0104] It should also be noted that the insulating shell 13 includes a base sheet 131 , a main folding sheet 132 , and a side folding sheet 133 .

[0105] The substrate 131 is provided with one. In the wrapped state of the insulating shell 13, the substrate 131 is wrapped around the bottom of the battery cell group 12 and supports the battery cell group 12. In some embodiments, the substrate 131 can be a rectangular structure matching the bottom of the battery cell group 12.

[0106] There are two main folding pieces 132. The two main folding pieces 132 are arranged on opposite sides of the substrate 131 along the first direction a. Each main folding piece 132 can be integrally connected to the substrate 131, and each main folding piece 132 can be connected to the substrate 131 through a fourth fold line 1321. The fourth fold line 1321 can be a marking line, a weakened mark, a dotted printed line, etc. printed on the insulating shell 13. In the wrapped state of the insulating shell 13, each main folding piece 132 is bent about 90° along the fourth fold line 1321 relative to the substrate 131, and covers the corresponding side of the battery cell group 12 along the first direction a, that is, the two main folding pieces 132 respectively cover the opposite sides of the battery cell group 12 along the first direction a. In some embodiments, the main folding piece 132 can be a rectangular structure that matches the corresponding side of the battery cell group 12.

[0107] Along the second direction b perpendicular to the first direction a, the insulating shell 13 may have a first side 135. Among them, one side of the insulating shell 13 along the second direction b may be the first side 135, that is, only one side of the insulating shell 13 along the second direction b adopts the relevant design mentioned in the present application, and the other side may adopt other designs to achieve the corresponding side of the battery cell group 12 along the second direction b. Alternatively, both opposite sides of the insulating shell 13 along the second direction b may be the first side 135, that is, both opposite sides of the insulating shell 13 along the second direction b adopt the relevant design mentioned in the present application.

[0108] It should also be noted that, on the first side 135, at least one main folding piece 132 is connected to a side folding piece 133 corresponding to the side of the first side 135, and the connected main folding pieces 132 and side folding pieces 133 may be integrally connected. In some embodiments, a main folding piece 132 may be connected to a side folding piece 133 via a transition angle 136, that is, a side folding piece 133 is provided on the first side 135. In this case, in the wrapped state of the insulating shell 13, the size of the side folding piece 133 along the first direction a is greater than or equal to the size of the battery cell group 12 along the first direction a, so that the side folding piece 133 can be bent relative to the main folding piece 132 to the corresponding side of the battery cell group 12 (that is, the side corresponding to the first side 135), and wrap the corresponding side of the battery cell group 12. In other embodiments, both main folding pieces 132 may be connected to side folding pieces 133 via transition angles 136, that is, two side folding pieces 133 are provided on the first side 135. In this case, in the wrapped state of the insulating shell 13, the sum of the dimensions of the two side folding pieces 133 along the first direction a is greater than or equal to the dimension of the battery cell group 12 along the first direction a, so that the two side folding pieces 133 can be bent to the same side of the battery cell group 12 relative to the main folding piece 132, and jointly wrap the corresponding side of the battery cell group 12. The shape of the side folding piece 133 can be designed in a variety of ways, such as being rectangular, etc.

[0109] The connected main folding piece 132 and the side folding piece 133 are transitionally connected via a transition angle 136. Each transition angle 136 is connected to the main folding piece 132 via a first fold line 1361, and each transition angle 136 is connected to the side folding piece 133 via a second fold line 1362. The first fold line 1361 and the second fold line 1362 can be marking lines, weakened marks, dotted printed lines, etc. printed on the insulating shell 13. In the wrapped state of the insulating shell 13, each transition angle 136 is bent along the first fold line 1361 relative to the main folding piece 132, and the side folding piece 133 connected to the transition angle 136 is bent along the second fold relative to the transition angle 136, so that the side folding piece 133 is bent relative to the main folding piece 132 to the corresponding side of the battery cell group 12. The transition angle 136 can be a rounded corner or a chamfer.

[0110] It should also be noted that, on the first side 135, the side of the base sheet 131 corresponding to the first side 135 is connected with an extension fold 134, and the extension fold 134 and the base sheet 131 can be integrally connected. The extension fold 134 and the base sheet 131 are connected via a third fold line 1341. The third fold line 1341 can be a marking line, a weakening mark, a dotted printed line, etc. printed on the insulating shell 13.

[0111] In the wrapped state of the insulating shell 13, the extended folding piece 134 can be bent along the third folding line 1341 relative to the base sheet 131 to the corresponding side of the battery cell group 12, and mainly covers the corresponding side and bottom corner areas of the battery cell group 12, and covers the gap between the corresponding side folding piece 133 and the base sheet 131, so that at the gap between the corresponding side folding piece 133 and the base sheet 131, the battery cell group 12 and the outer shell 11 can be insulated and isolated by the extended folding piece 134, thereby improving the insulation effect of the insulating shell 13 between the battery cell group 12 and the outer shell 11.

[0112] In the case where one side fold piece 133 is provided on the first side 135, the extension fold piece 134 can be folded to the outside of the side fold piece 133 or to the inside of the side fold piece 133. In the case where two side fold pieces 133 are provided on the first side 135, the extension fold piece 134 can be folded to the outside of the two side fold pieces 133 or to between the two side fold pieces 133 or to the inside of the two side fold pieces 133.

[0113] It should also be noted that the unfolded state of the insulating shell 13 is the state before the insulating shell 13 is folded and transformed into the wrapped state. The insulating shell 13 is laid flat in the unfolded state.

[0114] In some embodiments, when the insulating shell 13 is in the unfolded state, on the first side 135 , the third fold line 1341 is offset from the straight line where the first fold line 1361 is located, and is also offset from the straight line where the second fold line 1362 is located.

[0115] In some other embodiments, when the insulating shell 13 is in the unfolded state, on the first side 135 , the third fold line 1341 is offset from the straight line where the first fold line 1361 is located, or is offset from the straight line where the second fold line 1362 is located.

[0116] Since the area from the first fold line 1361 to the second fold line 1362 is mainly used to form the outer surface of the transition angle 136 (such as a rounded arc surface, a chamfered slope, etc.), by making the third fold line 1341 in the unfolded state of the insulating shell 13 offset from the straight line where at least one of the first fold line 1361 and the second fold line 1362 is located, it is convenient for the extended fold sheet 134 to be smoothly bent to the corresponding side of the battery cell group 12, and the risk of mutual interference between the extended fold sheet 134 and the corresponding side fold sheet 133 can be reduced. Furthermore, when the extension folding piece 134 is bent along the third folding line 1341 to the corresponding side surface of the battery cell group 12, the extension folding piece 134 can be brought close to the corresponding side folding piece 133, thereby reducing the risk of a large gap between the extension folding piece 134 and the corresponding side folding piece 133, optimizing the insulation effect of the side folding piece 133 and the extension folding piece 134 on the first side 135, and optimizing the insulation effect of the insulation shell 13 between the battery cell group 12 and the outer shell 11.

[0117] In summary, in the battery cell 10 provided in the embodiment of the present application, the insulating shell 13 can support the battery cell group 12 through the substrate 131, and respectively cover the two opposite sides of the battery cell group 12 along the first direction a through the two main folding pieces 132 disposed on the opposite sides of the substrate 131 along the first direction a. On this basis, the insulating shell 13 can also cover the corresponding side of the battery cell group 12 on the first side 135 through the side folding piece 133 connected to at least one main folding piece 132, and fold to the corresponding side of the battery cell group 12 through the extension folding piece 134 connected to the substrate 131 to cover the gap between the corresponding side folding piece 133 and the substrate 131, so that at the gap between the corresponding side folding piece 133 and the substrate 131, the extension folding piece 134 can effectively insulate and isolate the battery cell group 12 and the shell 11. Based on this, the relatively comprehensive and reliable insulating shell 13 can be reliably covered on the outside of the battery cell group 12, and the battery cell group 12 and the outer shell 11 can be reliably insulated and isolated, thereby improving the insulation effect of the insulating shell 13 between the battery cell group 12 and the outer shell 11, reducing the risk of the battery cell group 12 contacting the outer shell 11 through the seam gap of the insulating shell 13, and reducing the risk of corrosion of the outer shell 11 due to direct contact between the battery cell group 12 and the outer shell 11.

[0118] In addition, in this embodiment, the third fold line 1341 is arranged to be offset from the straight line where at least one of the first fold line 1361 and the second fold line 1362 is located on the first side 135 in the unfolded state of the insulating shell 13, so that the extension folded piece 134 can be smoothly bent to the corresponding side of the battery cell group 12, and the risk of mutual interference between the extension folded piece 134 and the corresponding side folded piece 133 can be reduced. In addition, when the extension folded piece 134 is bent to the corresponding side of the battery cell group 12 along the third folded line 1341, the extension folded piece 134 can be close to the corresponding side folded piece 133, thereby reducing the risk of a large gap between the extension folded piece 134 and the corresponding side folded piece 133, optimizing the insulation effect of the side folded piece 133 and the extension folded piece 134 on the first side 135, and optimizing the insulation effect of the insulating shell 13 between the battery cell group 12 and the outer shell 11.

[0119] See also Figure 3 , Figure 4 , Figure 5 In some embodiments of the present application, the third fold line 1341 is located between the straight line where the first fold line 1361 is located and the straight line where the second fold line 1362 is located when the insulating shell 13 is in the unfolded state.

[0120] It should be noted that, in the unfolded state of the insulating shell 13, on the first side 135, since the area from the first fold line 1361 to the second fold line 1362 is mainly used to form the outer surface of the transition angle 136 (such as a rounded arc surface, a chamfered slope, etc.), the third fold line 1341 is between the straight line where the first fold line 1361 is located and the straight line where the second fold line 1362 is located.

[0121] By adopting the above scheme, by making the third fold line 1341 between the straight line where the first fold line 1361 and the straight line where the second fold line 1362 are located in the unfolded state of the insulating shell 13, it is convenient to facilitate the extension folding piece 134 to be smoothly and smoothly bent to the corresponding side of the battery cell group 12, and the risk of interference between the extension folding piece 134 and the corresponding side folding piece 133 can be reduced. Furthermore, when the extension folded piece 134 is bent along the third fold line 1341 to the corresponding side surface of the battery cell group 12, the extension folded piece 134, especially the corner area between the extension folded piece 134 and the base sheet 131, can be close to the corresponding side folded piece 133, thereby reducing the risk of a gap or crack between the extension folded piece 134 (especially the corner area between the extension folded piece 134 and the base sheet 131) and the corresponding side folded piece 133, and optimizing the insulation effect of the side folded piece 133 and the extension folded piece 134 on the first side 135, and optimizing the insulation effect of the insulation shell 13 between the battery cell group 12 and the outer shell 11. This embodiment is particularly suitable for the situation where "the extension folded piece 134 is folded to the outside of the corresponding side folded piece 133".

[0122] See also Figure 3 , Figure 5 , Figure 6 In some embodiments of the present application, the extension flap 134 is folded to the outside of the corresponding side flap 133 .

[0123] It should be noted that, when one side fold piece 133 is provided on the first side 135, the extension fold piece 134 can be folded to the outside of the side fold piece 133. When two side fold pieces 133 are provided on the first side 135, the extension fold piece 134 can be folded to the outside of the two side fold pieces 133.

[0124] By adopting the above scheme, when the side folding pieces 133, the main folding pieces 132 and the base sheet 131 cooperate to cover the battery cell group 12, the extension folding pieces 134 can be folded to the outside of the corresponding side folding pieces 133, so that the gap between the corresponding side folding pieces 133 and the base sheet 131 can be reliably covered by the extension folding pieces 134. Based on this, the bending of the extension folding pieces 134 can be facilitated, especially the connection and fixation of the side folding pieces 133 and the extension folding pieces 134 can be facilitated, the covering effect of the extension folding pieces 134 on the gap between the side folding pieces 133 and the base sheet 131 can be visually optimized, and the risk of the extension folding pieces 134 missing the covering gap can be reduced. As a result, the folding convenience of the insulating shell 13 can be improved, the structural reliability and structural stability of the insulating shell 13 in the covering state can be improved, the risk of the insulating shell 13 falling apart can be reduced, and the insulation effect of the insulating shell 13 between the battery cell group 12 and the outer shell 11 can be optimized. In addition, by folding the extension folding piece 134 to the outside of the corresponding side folding piece 133 , the side folding piece 133 can be fitted and wrapped around the corresponding side of the battery cell group 12 , thereby optimizing the insulation covering property of the side folding piece 133 on the corresponding side of the battery cell group 12 .

[0125] Of course, in other embodiments, when one side fold piece 133 is provided on the first side 135, the extension fold piece 134 can be folded to the inner side of the side fold piece 133. When two side fold pieces 133 are provided on the first side 135, the extension fold piece 134 can be folded between the two side fold pieces 133, or can be folded to the inner side of the two side fold pieces 133.

[0126] See also Figure 3 , Figure 4 , Figure 5 , Figure 6 In some embodiments of the present application, on the first side 135 , the two main folding pieces 132 are connected to the side folding pieces 133 via the transition angle 136 , and the two side folding pieces 133 jointly cover the corresponding sides of the battery cell group 12 .

[0127] It should be noted that, on the first side 135, the two main folding pieces 132 are connected to the side folding pieces 133 via the transition angle 136, that is, two side folding pieces 133 are provided on the first side 135. In the wrapped state of the insulating shell 13, the sum of the dimensions of the two side folding pieces 133 along the first direction a is greater than or equal to the dimension of the battery cell group 12 along the first direction a. In this way, the two side folding pieces 133 can be bent to the same side of the battery cell group 12 relative to the main folding piece 132, and jointly cover the corresponding side of the battery cell group 12.

[0128] By adopting the above solution, in the wrapped state of the insulating shell 13, the first side 135 can be bent to the same side of the battery cell group 12 through the two side folding pieces 133 respectively connected to the two main folding pieces 132, and together wrap the corresponding side of the battery cell group 12. Based on this, on the one hand, the convenience of bending the two side folding pieces 133 toward each other and wrapping the same side of the battery cell group 12 can be improved, so that the folding convenience of the insulating shell 13 can be improved, and the convenience of assembling the insulating shell 13 and the battery cell group 12 can be improved. On the one hand, the connection gap between the two side folding pieces 133 can be located in the middle of the corresponding side of the battery cell group 12, which can improve the connection strength between the two side folding pieces 133, balance the stress of the two side folding pieces 133 during the expansion of the battery cell group 12, reduce the risk of the two side folding pieces 133 falling apart and being stretched open, and enable the two side folding pieces 133 to firmly and firmly insulate and wrap the corresponding side of the battery cell group 12, thereby improving the insulation wrapping effect of the two side folding pieces 133 on the corresponding side of the battery cell group 12, and optimizing the insulation effect of the insulation shell 13 between the battery cell group 12 and the outer shell 11.

[0129] Of course, in other embodiments, a main folding piece 132 may be connected to a side folding piece 133 via a transition angle 136 on the side corresponding to the first side 135, that is, a side folding piece 133 is provided on the first side 135, and in the wrapped state of the insulating shell 13, the size of the side folding piece 133 along the first direction a is greater than or equal to the size of the battery cell group 12 along the first direction a, so that the side folding piece 133 can be bent to the corresponding side of the battery cell group 12 relative to the main folding piece 132, and wrap the corresponding side of the battery cell group 12.

[0130] See also Figure 3 , Figure 5 , Figure 6 In some embodiments of the present application, the extension flap 134 is folded to the outside of the two side flaps 133 .

[0131] It should be noted that, when two side fold pieces 133 are provided on the first side 135 , the extension fold piece 134 can be folded to the outside of the two side fold pieces 133 .

[0132] By adopting the above scheme, on the first side 135, when the two side folding pieces 133 jointly cover the corresponding side surfaces of the battery cell group 12, the extension folding piece 134 can be folded to the outside of the two side folding pieces 133, so as to reliably cover the gap between the two side folding pieces 133 and the base sheet 131 through the extension folding piece 134. Based on this, the bending of the extension folding piece 134 can be facilitated, especially the connection and fixation of the extension folding piece 134 with the two side folding pieces 133 can be facilitated, the covering effect of the extension folding piece 134 on the gap between the two side folding pieces 133 and the base sheet 131 can be visually optimized, and the risk of the extension folding piece 134 missing the covering gap can be reduced. As a result, the folding convenience of the insulating shell 13 can be improved, the structural reliability and structural stability of the insulating shell 13 in the covering state can be improved, the risk of the insulating shell 13 falling apart can be reduced, and the insulation effect of the insulating shell 13 between the battery cell group 12 and the outer shell 11 can be optimized. In addition, by folding the extended folding piece 134 to the outside of the two side folding pieces 133, the two side folding pieces 133 can reliably, comprehensively and snugly cover the corresponding sides of the battery cell group 12, thereby optimizing the insulation covering effect of the two side folding pieces 133 on the corresponding sides of the battery cell group 12.

[0133] Of course, in other embodiments, the extension flap 134 can be folded between the two side flaps 133 , or folded to the inner side of the two side flaps 133 .

[0134] See also Figure 3 , Figure 5 , Figure 6 In some embodiments of the present application, on the first side 135, the two side folds 133 are respectively a first side fold 133a and a second side fold 133b, and a portion of the first side fold 133a is folded to the outside of the second side fold 133b.

[0135] It should be noted that, when two side folding pieces 133 are provided on the first side 135, the second side folding piece 133b can be firstly bent to the corresponding side of the battery cell group 12, and then the first side folding piece 133a can be bent to the same side of the battery cell group 12, and a part of the first side folding piece 133a is covered on the outside of the second side folding piece 133b. That is, in the wrapped state of the insulating shell 13, on the first side 135, along the second direction b, the projections of the first side folding piece 133a and the second side folding piece 133b are overlapped.

[0136] By adopting the above solution, in the wrapped state of the insulating shell 13, the first side 135 can cover the corresponding side surface of the battery cell group 12 together via the first side folding piece 133a and the second side folding piece 133b whose projections overlap along the second direction b. Based on this, the first side fold sheet 133a can form a pressing effect on the second side fold sheet 133b through the part folded to the outside of the second side fold sheet 133b, thereby enhancing the connection strength between the first side fold sheet 133a and the second side fold sheet 133b, and can help maintain the shape of the first side fold sheet 133a and the second side fold sheet 133b during the expansion of the battery cell group 12, and can reduce the risk of the first side fold sheet 133a and the second side fold sheet 133b falling apart and being stretched apart, and can enable the first side fold sheet 133a and the second side fold sheet 133b to reliably, durably and comprehensively insulate and cover the corresponding side surfaces of the battery cell group 12, thereby optimizing the insulating covering effect of the first side fold sheet 133a and the second side fold sheet 133b on the corresponding side surfaces of the battery cell group 12, and optimizing the insulating effect of the insulating shell 13 between the battery cell group 12 and the outer shell 11. Moreover, in the wrapped state of the insulating shell 13, even if there are processing errors in the dimensions of the battery cell group 12, the first side fold piece 133a, and the second side fold piece 133b along the first direction a, due to the overlapping portion of the first side fold piece 133a and the second side fold piece 133b, the first side fold piece 133a and the second side fold piece 133b can be compatible with dimensional deviations within a certain range, and can still fully insulate and wrap the corresponding sides of the battery cell group 12, thereby improving the dimensional compatibility, applicability and reliability of the insulating shell 13.

[0137] Of course, in other embodiments, in the wrapped state of the insulating shell 13, the sum of the dimensions of the first side fold piece 133a and the second side fold piece 133b along the first direction a is equal to the dimension of the battery cell group 12 along the first direction a, so that the first side fold piece 133a and the second side fold piece 133b are just adjacent to each other and jointly wrap the corresponding side surfaces of the battery cell group 12.

[0138] See also Figure 3 , Figure 4 , Figure 5 In some embodiments of the present application, a first notch 1331 is provided in a portion of the first side fold piece 133a folded to the outside of the second side fold piece 133b.

[0139] It should be noted that the first side folding piece 133a is provided with a first notch 1331. The first notch 1331 is provided at the portion where the first side folding piece 133a is folded to the outside of the second side folding piece 133b, so that the first notch 1331 can expose the corresponding area of ​​the second side folding piece 133b. The shape of the first notch 1331 can be designed in a variety of ways, and can be, but not limited to, a triangle, a rectangle, etc.

[0140] By adopting the above scheme, in the wrapped state of the insulating shell 13, on the first side 135, the part of the first side fold piece 133a folded to the outside of the second side fold piece 133b can be exposed through the first notch 1331 to expose the corresponding area of ​​the second side fold piece 133b, so that the bonding structure (such as tape) can pass through the first notch 1331 to reliably and firmly bond and fix the first side fold piece 133a and the second side fold piece 133b. Based on this, the connection convenience, connection reliability and connection strength between the first side fold piece 133a and the second side fold piece 133b can be improved, the risk of the first side fold piece 133a and the second side fold piece 133b falling apart can be reduced, and the first side fold piece 133a and the second side fold piece 133b can be enabled to reliably and durably insulate and wrap the corresponding sides of the battery cell group 12, thereby optimizing the insulating wrapping effect of the first side fold piece 133a and the second side fold piece 133b on the corresponding sides of the battery cell group 12, and optimizing the insulating effect of the insulating shell 13 between the battery cell group 12 and the outer shell 11.

[0141] Of course, in other embodiments, the first side fold piece 133a and the second side fold piece 133b may be fixed along other positions such as the edge position of the first side fold piece 133a or the overlapping position of the first side fold piece 133a and the second side fold piece 133b.

[0142] See also Figure 4 , Figure 5 , Figure 6 , Figure 7 In some embodiments of the present application, the extension flap 134 is folded to the outside of the first side flap 133a and the second side flap 133b, or the extension flap 134 is folded between the first side flap 133a and the second side flap 133b. The first notch 1331 is provided at one end of the first side flap 133a close to the extension flap 134, and a part of the first notch 1331 is exposed outside the extension flap 134.

[0143] It should be noted that, when the extension fold 134 is folded outside the first side fold 133a, or the extension fold 134 is folded between the first side fold 133a and the second side fold 133b, the first notch 1331 can be set at one end of the first side fold 133a close to the extension fold 134, and partially exceed and expose outside the extension fold 134, so that near the first notch 1331, the first side fold 133a, the second side fold 133b, and the extension fold 134 all have exposed portions.

[0144] By adopting the above scheme, when the extension flap 134 is folded outside the first side flap 133a, or when the extension flap 134 is folded between the first side flap 133a and the second side flap 133b, the first notch 1331 can be provided at one end of the first side flap 133a close to the extension flap 134, and a part of the first notch 1331 is exposed outside the extension flap 134, so that the part of the first notch 1331 exposed outside the extension flap 134 can expose the corresponding area of ​​the second side flap 133b. Based on this, near the first notch 1331, the first side flap 133a, the second side flap 133b, and the extension flap 134 all have exposed parts, so that it is convenient for the adhesive structure (such as an adhesive tape) to pass through the first notch 1331, and reliably and firmly adhere and fix the first side flap 133a, the second side flap 133b, and the extension flap 134. Thus, the connection convenience, connection reliability and connection strength of the first side folding piece 133a, the second side folding piece 133b and the extension folding piece 134 can be improved, the risk of the first side folding piece 133a, the second side folding piece 133b and the extension folding piece 134 falling apart can be reduced, and the first side folding piece 133a, the second side folding piece 133b and the extension folding piece 134 can be reliably and durably insulated and wrapped around the battery cell group 12 (such as Figure 3 The corresponding side of the insulating shell 13 is shown in the figure, thereby optimizing the insulating covering effect of the first side fold sheet 133a, the second side fold sheet 133b and the extended fold sheet 134, and optimizing the insulating effect of the insulating shell 13.

[0145] Of course, in other embodiments, when the first notch 1331 is provided in the portion where the first side fold 133a is folded to the outside of the second side fold 133b, the first notch 1331 may be provided in other areas, such as the middle area of ​​the first side fold 133a in a direction perpendicular to the first direction a and the second direction b.

[0146] See also Figure 5 , Figure 6 , Figure 7 In some embodiments of the present application, the first notch 1331 is disposed at a corner of the first side fold 133a close to the extension fold 134 .

[0147] It should be noted that since the first notch 1331 is provided at the portion of the first side fold 133a folded outside the second side fold 133b, the first notch 1331 is provided at the corner of the first side fold 133a close to the second side fold 133b and the extension fold 134. The first notch 1331 may be, but is not limited to, triangular.

[0148] By adopting the above solution, by processing the first notch 1331 at the corner of the first side folded piece 133a close to the extension folded piece 134, it is convenient to form the first notch 1331 by cutting or cutting, which is convenient for processing the first notch 1331 and for accurately controlling the size of the first notch 1331. In addition, since the first notch 1331 is provided at the corner, the effect of processing the first notch 1331 on the structural strength of the first side folded piece 133a can be reduced, the risk of cracking or fissures in the first side folded piece 133a near the first notch 1331 can be reduced, and the insulation coating and service life of the first side folded piece 133a can be maintained.

[0149] Of course, in other embodiments, when the first notch 1331 is provided at the portion where the first side fold piece 133a is folded to the outside of the second side fold piece 133b, the first notch 1331 may be provided at a non-corner region of the first side fold piece 133a.

[0150] See also Figure 4 In some embodiments of the present application, along a direction perpendicular to the third fold line 1341 , a dimension d1 of the extended fold piece 134 ranges from 5 mm to 15 mm.

[0151] It should be noted that the dimension d1 of the extension flap 134 along the direction perpendicular to the third fold line 1341 may correspond to the dimension of the extension flap 134 along the direction perpendicular to the first direction a and the second direction b when the insulating shell 13 is wrapped; and may correspond to the dimension of the extension flap 134 along the second direction b when the insulating shell 13 is unfolded. Along the direction perpendicular to the third fold line 1341, the dimension d1 of the extension flap 134 ranges from 5 mm to 15 mm, for example, 5 mm, 6 mm, 7 mm, 8 mm, 9 mm, 10 mm, 11 mm, 12 mm, 13 mm, 14 mm, 15 mm, etc.

[0152] By adopting the above scheme, by making the size d1 of the extension folding piece 134 range from 5mm to 15mm along the direction perpendicular to the third folding line 1341, the extension folding piece 134 can reliably cover the gap between the corresponding side folding piece 133 and the base sheet 131 when it is folded to the corresponding side of the battery cell group 12, and can also correspondingly constrain the size of the extension folding piece 134 to reduce the amount of consumables of the adhesive structure (such as tape) used to fix the extension folding piece 134, and reduce the risk of warping of the extension folding piece 134 after fixation.

[0153] Of course, in other embodiments, since the extended folding piece 134 can cover the gap between the corresponding side folding piece 133 and the base sheet 131 when it is folded to the corresponding side of the battery cell group 12, the dimension d1 of the extended folding piece 134 along the direction perpendicular to the third fold line 1341 can be set to be greater than 0 and less than 5 mm, or can be set to be greater than 15 mm and less than the dimension of the battery cell group 12 along the direction perpendicular to the first direction a and the second direction b.

[0154] See also Figure 3 , Figure 4 , Figure 5 , Figure 8 In some embodiments of the present application, a second notch 1342 is provided between the extension flap 134 and the side flap 133 adjacent thereto.

[0155] It should be noted that, when one side folding piece 133 is provided on the first side 135, a second notch 1342 is provided between the extension folding piece 134 and one of the side folding pieces 133 provided adjacent thereto. When two side folding pieces 133 are provided on the first side 135, a second notch 1342 is provided between the extension folding piece 134 and the two side folding pieces 133 provided adjacent thereto, respectively, that is, a second notch 1342 is provided on each of the two opposite sides of the extension folding piece 134 along the first direction a, that is, the extension folding piece 134 corresponds to two second notches 1342. The second notch 1342 can be designed in various shapes, and can be, but not limited to, a triangle, a rectangle, etc.

[0156] By adopting the above solution, by providing the second notch 1342 between the extension folding piece 134 and the side folding piece 133 disposed adjacent thereto, the pulling effect of the extension folding piece 134 on the adjacent side folding piece 133 can be reduced during the period when the extension folding piece 134 is folded to the corresponding side surface of the battery cell group 12, thereby optimizing the folding convenience and folding quality of the insulating shell 13, and improving the flatness and accuracy of the folding of the extension folding piece 134 and the side folding piece 133. In addition, the provision of the second notch 1342 also helps to reduce the stress concentration in the area adjacent to the side folding piece 133 and the extension folding piece 134, thereby reducing the risk of deformation or rupture of the area adjacent to the side folding piece 133 and the extension folding piece 134, and optimizing the structural strength and service life of the side folding piece 133.

[0157] Of course, in other embodiments, the extension flap 134 and the side flap 133 adjacent thereto may be separated from each other via a cutting seam, and the second notch 1342 may be omitted.

[0158] See also Figure 3 , Figure 4 , Figure 6 In some embodiments of the present application, at least one corner of the substrate 131 is rounded.

[0159] It should be noted that, since the substrate 131 is coated on the bottom of the battery cell group 12 and supports the battery cell group 12 in the coated state of the insulating shell 13, the shape and size of the substrate 131 basically correspond to the shape and size of the bottom of the battery cell group 12. The substrate 131 may be, but is not limited to, a polygon such as a rectangle, and the substrate 131 has a corner. At least one corner of the substrate 131 may be set as a rounded corner. In some embodiments, each corner of the substrate 131 may be rounded.

[0160] By adopting the above scheme, by making at least one corner of the substrate 131 rounded, the risk of interference between the substrate 131 of the insulating shell 13 and the bottom surface of the battery cell group 12 can be reduced during the assembly of the battery cell group 12 and the insulating shell 13, and the risk of interference between the corners of the substrate 131 of the insulating shell 13 and the outer shell 11 can be reduced during the assembly of the insulating shell 13 and the outer shell 11, thereby improving the convenience of assembling the insulating shell 13 with the battery cell group 12 and the outer shell 11, reducing the risk of damage to the corners of the insulating shell 13 due to friction, impact, shock, etc. during assembly, reducing the risk of damage to the insulating shell 13 during assembly, and improving the performance and service life of the insulating shell 13.

[0161] Of course, in other embodiments, the corners of the substrate 131 may not be rounded, for example, the corners of the substrate 131 may all be right angles.

[0162] See also Figure 3 , Figure 4 , Figure 6 In some embodiments of the present application, the corners of the base sheet 131 adjacent to the extension flap 134 are rounded. Along the first direction a, the width d2 of the extension flap 134 is equal to the width d3 of the base sheet 131 minus the dimensions of the two corners of the base sheet 131 adjacent to the extension flap 134 (i.e., d4 and d5).

[0163] It should be noted that, on the first side 135, the two corners of the base sheet 131 adjacent to the extension flap 134 are both rounded. Of the two corners, the dimension of one corner along the first direction a is d4, which may be equal to but not limited to the radius of the corner; the dimension of the other corner along the first direction a is d5, which may be equal to but not limited to the radius of the corner.

[0164] On the first side 135, along the first direction a, the width d2 of the extension flap 134 is equal to: the width d3 of the base sheet 131 minus the dimension d4 of one corner of the base sheet 131 adjacent to the extension flap 134, minus the dimension d5 of another corner of the base sheet 131 adjacent to the extension flap 134. That is, d2 = d3 - d4 - d5.

[0165] By adopting the above solution, along the first direction a, the width d2 of the extension flap 134 is equal to: the width d3 of the base sheet 131 minus the dimension d4 of one of the corners of the base sheet 131 adjacent to the extension flap 134, and then minus the dimension d5 of another corner of the base sheet 131 adjacent to the extension flap 134; the extension flap 134 can completely cover the gap between the corresponding edge of the base sheet 131 and the corresponding side flap 133. Based on this, the covering effect of the extension flap 134 on the gap between the side flap 133 and the base sheet 131 can be optimized, and the risk of the extension flap 134 missing the covering gap can be reduced, so that the insulation effect of the side flap 133 and the extension flap 134 on the first side 135 can be optimized, and the insulation effect of the insulation shell 13 between the battery cell group 12 and the outer shell 11 can be optimized.

[0166] Of course, in other embodiments, along the first direction a, the width d2 of the extended folded piece 134 may be less than or equal to the width d3 of the base piece 131 .

[0167] See also Figure 3 , Figure 4 , Figure 8 In some embodiments of the present application, the second notch 1342 is formed between the extended folded piece 134, the corner of the base sheet 131 disposed adjacent thereto, and the side folded piece 133 disposed adjacent thereto.

[0168] It should be noted that, based on the previous embodiment, the second notch 1342 can be formed directly through the gap between the extended folded piece 134, the corner of the base sheet 131 adjacent to the extended folded piece 134, and the side folded piece 133 adjacent to the extended folded piece 134, without cutting off the material to form the second notch 1342. In the unfolded state of the insulating shell 13, the shape of the second notch 1342 is trapezoidal, and the hypotenuse of the trapezoid is an arc formed by the rounded corners.

[0169] By adopting the above scheme, on the basis of the previous embodiment, the second notch 1342 can be formed by the extension folding piece 134, the corner of the base sheet 131 adjacent to the extension folding piece 134, and the side folding piece 133 adjacent to the extension folding piece 134. Based on this, the pulling effect of the extension folding piece 134 on the adjacent side folding piece 133 can be reduced during the period when the extension folding piece 134 is folded to the corresponding side of the battery cell group 12, thereby optimizing the folding convenience and folding quality of the insulating shell 13, and improving the flatness and accuracy of the folding of the extension folding piece 134 and the side folding piece 133. In addition, the second notch 1342 can be formed by the size of the extension folding piece 134, the corner of the base sheet 131, and the side folding piece 133, without the need to be formed by cutting materials, thereby improving the forming convenience of the second notch 1342 and optimizing the overall structure of the insulating shell 13. In addition, the provision of the second notch 1342 also helps to reduce stress concentration in the adjacent areas of the side fold pieces 133, the corners of the base piece 131 and the extended fold piece 134, thereby reducing the risk of deformation or rupture in the adjacent areas of the side fold pieces 133, the corners of the base piece 131 and the extended fold piece 134, and optimizing the structural strength and service life of the insulating shell 13.

[0170] Of course, in other embodiments, the second notch 1342 may be formed in other ways, such as by cutting away material.

[0171] See also Figure 4 In some embodiments of the present application, the first fold line 1361 is spaced apart from the corresponding side of the main fold piece 132 at at least one end of its extension direction.

[0172] It should be noted that, in some embodiments, the first fold line 1361 is spaced apart from the corresponding side of the main fold piece 132 at one end of its extension direction, that is, the first fold line 1361 does not extend continuously to the corresponding side of the main fold piece 132 at one end of its extension direction.

[0173] like Figure 4 As shown, in other embodiments, the first fold line 1361 is spaced apart from the corresponding sides of the main fold piece 132 at the opposite ends in its extension direction, that is, the first fold line 1361 does not extend continuously to the corresponding sides of the main fold piece 132 at the opposite ends in its extension direction.

[0174] The corresponding side of the main fold piece 132 refers to the side of the main fold piece 132 corresponding to the end defined by the first fold line 1361 along the extension direction of the first fold line 1361 .

[0175] The extension direction of the first fold line 1361 intersects (eg is perpendicular to) the second direction b. In the unfolded state of the insulation shell 13, the extension direction of the first fold line 1361 may be parallel to (but not limited to) the first direction a.

[0176] By adopting the above solution, by setting at least one end of the first fold line 1361 in the extension direction thereof at a distance from the corresponding side of the main fold piece 132, the first fold line 1361 can be made not to penetrate the main fold piece 132 in the extension direction thereof. Based on this, the main fold piece 132 and the transition corner 136 can have a stronger connection strength in the area where the first fold line 1361 does not extend, and the connection strength, connection reliability and durability between the main fold piece 132 and the transition corner 136 can be maintained and improved, and the risk of cracks, splits and tears in the connection area between the main fold piece 132 and the transition corner 136 can be reduced, thereby improving the structural reliability and service life of the insulating shell 13.

[0177] See also Figure 4 In some embodiments of the present application, the second fold line 1362 is spaced apart from the corresponding side of the side fold piece 133 at at least one end of its extension direction.

[0178] It should be noted that, in some embodiments, the second fold line 1362 is spaced apart from the corresponding side of the side fold piece 133 at one end of its extension direction, that is, the second fold line 1362 does not extend continuously to the corresponding side of the side fold piece 133 at one end of its extension direction.

[0179] like Figure 4 As shown, in other embodiments, the second fold line 1362 is spaced apart from the corresponding sides of the side fold piece 133 at the opposite ends of its extension direction, that is, the second fold line 1362 does not extend continuously to the corresponding sides of the side fold piece 133 at the opposite ends of its extension direction.

[0180] The corresponding side of the side fold piece 133 refers to the side of the side fold piece 133 corresponding to the end defined by the second fold line 1362 along the extension direction of the second fold line 1362 .

[0181] The extension direction of the second fold line 1362 intersects (eg is perpendicular to) the second direction b. In the unfolded state of the insulation shell 13, the extension direction of the second fold line 1362 may be parallel to (but not limited to) the first direction a.

[0182] By adopting the above solution, by setting the second fold line 1362 at least one end in its extension direction at a distance from the corresponding side of the side fold piece 133, the second fold line 1362 can be made not to penetrate the side fold piece 133 in its extension direction. Based on this, the side fold piece 133 and the transition corner 136 can have a strong connection strength in the area where the second fold line 1362 does not extend, and the connection strength, connection reliability and durability between the side fold piece 133 and the transition corner 136 can be maintained and improved, and the risk of cracks, splits and tears in the connection area between the side fold piece 133 and the transition corner 136 can be reduced, thereby improving the structural reliability and service life of the insulating shell 13.

[0183] See also Figure 4 In some embodiments of the present application, the third fold line 1341 is spaced apart from the corresponding side of the extension fold sheet 134 at at least one end of the third fold line 1341 in its extension direction.

[0184] It should be noted that, in some embodiments, the third fold line 1341 is spaced apart from the corresponding side of the extension fold 134 at one end of its extension direction, that is, the third fold line 1341 does not extend continuously to the corresponding side of the extension fold 134 at one end of its extension direction.

[0185] like Figure 4 As shown, in other embodiments, the third fold line 1341 is spaced apart from the corresponding sides of the extension fold 134 at the opposite ends in its extension direction, that is, the third fold line 1341 does not extend continuously to the corresponding sides of the extension fold 134 at the opposite ends in its extension direction.

[0186] The corresponding side of the extension flap 134 refers to the side of the extension flap 134 corresponding to the end defined by the third fold line 1341 along the extension direction of the third fold line 1341 .

[0187] The extension direction of the third fold line 1341 intersects (eg is perpendicular to) the second direction b. In the unfolded state of the insulation shell 13, the extension direction of the third fold line 1341 may be parallel to (but not limited to) the first direction a.

[0188] By adopting the above solution, by setting at least one end of the third fold line 1341 in the extension direction to be spaced from the corresponding side of the extension folded piece 134, the third fold line 1341 can be made not to penetrate the extension folded piece 134 in the extension direction. Based on this, the extension folded piece 134 and the base sheet 131 can have a stronger connection strength in the area where the third fold line 1341 is not extended, and the connection strength, connection reliability and durability between the extension folded piece 134 and the base sheet 131 can be maintained and improved, and the risk of cracks, splits and tears in the connection area between the extension folded piece 134 and the base sheet 131 can be reduced, thereby improving the structural reliability and service life of the insulating shell 13.

[0189] See also Figure 4 , Figure 5 , Figure 6 In some embodiments of the present application, the extension flap 134 is a rectangular structure.

[0190] By adopting the above solution, by making the extension flap 134 a rectangular structure, the shape of the extension flap 134 can be regularized, and the extension flap 134 can have a regular and large surface area, can cover a wider area, and can reliably cover the gap between the corresponding side flap 133 and the base sheet 131, so as to optimize the covering effect of the extension flap 134 on the gap between the side flap 133 and the base sheet 131, and reduce the risk of the extension flap 134 missing the covering gap. In addition, the extension flap 134 with a rectangular structure can be easily processed, folded and installed.

[0191] Of course, in other embodiments, the extension flap 134 may be in other shapes, such as a trapezoidal shape.

[0192] See also Figure 3 , Figure 4 , Figure 6 In some embodiments of the present application, the transition corner 136 is a rounded corner.

[0193] By adopting the above scheme, by making the transition angle 136 a rounded angle, a rounded transition connection can be made between the connected main fold piece 132 and the side fold piece 133. Based on this, the stress concentration between the connected main fold piece 132 and the side fold piece 133 can be reduced, and the stress can be evenly distributed in the transition area between the connected main fold piece 132 and the side fold piece 133, thereby improving the connection strength and connection reliability between the connected main fold piece 132 and the side fold piece 133, reducing the risk of cracks and fissures in the connection area between the main fold piece 132 and the side fold piece 133, and optimizing the structural strength and service life of the insulating shell 13. Furthermore, during the assembly of the battery cell group 12 and the insulating shell 13, the rounded transition angle 136 can reduce the risk of interference between the edges of the insulating shell 13 and the battery cell group 12. During the assembly of the insulating shell 13 and the outer shell 11, the rounded transition angle 136 can reduce the risk of interference between the edges of the insulating shell 13 and the outer shell 11, thereby reducing the risk of damage to the edges of the insulating shell 13 due to friction, impact, shock, etc. during assembly, reducing the risk of damage to the insulating shell 13 during assembly, improving the convenience of assembling the insulating shell 13 with the battery cell group 12 and the outer shell 11, and improving the performance and service life of the insulating shell 13.

[0194] Of course, in other embodiments, the transition corner 136 may be a chamfer.

[0195] See also Figures 3 to 7 In summary, the present application provides a specific example of a battery cell 10 in the embodiment described above. The battery cell 10 includes a housing 11, a battery cell group 12, and an insulating shell 13. The battery cell group 12 is accommodated in the insulating shell 13, and the battery cell group 12 includes a plurality of electrode assemblies 121 arranged side by side. The insulating shell 13 is accommodated in the housing 11. The insulating shell 13 includes a base sheet 131, a main folding sheet 132, and a side folding sheet 133.

[0196] The substrate 131 supports the battery cell group 12. Each corner of the substrate 131 is rounded.

[0197] Two main folds 132 are provided and disposed on opposite sides of the base sheet 131 along the first direction a to respectively cover opposite sides of the battery pack 12 along the first direction a. Along a second direction b perpendicular to the first direction a, opposite sides of the insulation shell 13 are both first sides 135 .

[0198] On the first side 135: Both main folding pieces 132 are connected to side folding pieces 133 via transition angles 136. The transition angles 136 are rounded. Each transition angle 136 is connected to the main folding piece 132 via a first fold line 1361, and is connected to the side folding piece 133 via a second fold line 1362. The two side folding pieces 133 are respectively a first side folding piece 133a and a second side folding piece 133b, and a portion of the first side folding piece 133a is folded to the outside of the second side folding piece 133b, so that the two side folding pieces 133 jointly cover the corresponding side of the battery cell group 12. Based on this, the first side fold sheet 133a can form a pressing effect on the second side fold sheet 133b through the part folded to the outside of the second side fold sheet 133b, thereby enhancing the connection strength between the first side fold sheet 133a and the second side fold sheet 133b, and can help maintain the shape of the first side fold sheet 133a and the second side fold sheet 133b during the expansion of the battery cell group 12, and can reduce the risk of the first side fold sheet 133a and the second side fold sheet 133b falling apart and being stretched apart, and can enable the first side fold sheet 133a and the second side fold sheet 133b to reliably, durably and comprehensively insulate and cover the corresponding side surfaces of the battery cell group 12, thereby optimizing the insulating covering effect of the first side fold sheet 133a and the second side fold sheet 133b on the corresponding side surfaces of the battery cell group 12, and optimizing the insulating effect of the insulating shell 13 between the battery cell group 12 and the outer shell 11. Moreover, in the wrapped state of the insulating shell 13, even if there are processing errors in the dimensions of the battery cell group 12, the first side fold piece 133a, and the second side fold piece 133b along the first direction a, due to the overlapping portion of the first side fold piece 133a and the second side fold piece 133b, the first side fold piece 133a and the second side fold piece 133b can be compatible with dimensional deviations within a certain range, and can still fully insulate and wrap the corresponding sides of the battery cell group 12, thereby improving the dimensional compatibility, applicability and reliability of the insulating shell 13.

[0199] On the first side 135: the base sheet 131 is connected to the extension folded sheet 134 via the third fold line 1341. The third fold line 1341 is located between the straight line where the first fold line 1361 is located and the straight line where the second fold line 1362 is located when the insulating shell 13 is in the unfolded state. Along the first direction a, the width d2 of the extension folded sheet 134 is equal to: the width d3 of the base sheet 131 minus the dimension d4 of one of the corners of the base sheet 131 adjacent to the extension folded sheet 134, and minus the dimension d5 of the other corner of the base sheet 131 adjacent to the extension folded sheet 134, that is, d2 = d3-d4-d5. The extension folded sheet 134 is folded along the third fold line 1341 to the outside of the two side folded sheets 133, that is, folded to the outside of the first side folded sheet 133a. The extension folded sheet 134 covers the gap between the two side folded sheets 133 and the base sheet 131. Based on this, the bending of the extension folding piece 134 can be facilitated, especially the connection and fixation of the extension folding piece 134 with the two side folding pieces 133 can be facilitated, and the covering effect of the extension folding piece 134 on the gap between the two side folding pieces 133 and the base sheet 131 can be visually optimized, and the risk of the extension folding piece 134 missing the covering gap can be reduced. As a result, the folding convenience of the insulating shell 13 can be improved, the structural reliability and structural stability of the insulating shell 13 in the covering state can be improved, the risk of the insulating shell 13 falling apart can be reduced, and the insulation effect of the insulating shell 13 between the battery cell group 12 and the outer shell 11 can be optimized. In addition, by folding the extension folding piece 134 to the outside of the two side folding pieces 133, the two side folding pieces 133 can be reliably, comprehensively, and closely covered with the corresponding side surfaces of the battery cell group 12, thereby optimizing the insulation covering effect of the two side folding pieces 133 on the corresponding side surfaces of the battery cell group 12.

[0200] The first side flap 133a is provided with a first notch 1331 at a corner close to the extension flap 134 and the second side flap 133b, and a portion of the first notch 1331 is exposed outside the extension flap 134. Based on this, near the first notch 1331, the first side flap 133a, the second side flap 133b, and the extension flap 134 all have exposed portions, so that it is convenient for the adhesive structure (such as an adhesive tape) to pass through the first notch 1331 and reliably and firmly adhere and fix the first side flap 133a, the second side flap 133b, and the extension flap 134.

[0201] In the direction perpendicular to the third fold line 1341, the size d1 of the extension flap 134 ranges from 5 mm to 15 mm. Based on this, when the extension flap 134 is folded to the corresponding side of the battery cell group 12, it can reliably cover the gap between the corresponding side flap 133 and the base sheet 131, and the size of the extension flap 134 can be correspondingly constrained to reduce the amount of consumables of the adhesive structure (such as tape) used to fix the extension flap 134, and reduce the risk of warping of the extension flap 134 after fixation.

[0202] The second notch 1342 is formed by enclosing the extension folding piece 134, the corner of the substrate 131 disposed adjacent thereto, and the side folding piece 133 disposed adjacent thereto. Based on this, the pulling effect of the extension folding piece 134 on the adjacent side folding piece 133 can be reduced during the period when the extension folding piece 134 is folded to the corresponding side of the battery cell group 12, thereby optimizing the folding convenience and folding quality of the insulating shell 13, and improving the flatness and accuracy of the folding of the extension folding piece 134 and the side folding piece 133. In addition, the second notch 1342 can be formed by enclosing the size of the extension folding piece 134, the corner of the substrate 131, and the side folding piece 133, without having to be formed by cutting out materials, thereby improving the molding convenience of the second notch 1342 and optimizing the overall structure of the insulating shell 13. In addition, the provision of the second notch 1342 also helps to reduce stress concentration in the adjacent areas of the side fold pieces 133, the corners of the base piece 131 and the extended fold piece 134, thereby reducing the risk of deformation or rupture in the adjacent areas of the side fold pieces 133, the corners of the base piece 131 and the extended fold piece 134, and optimizing the structural strength and service life of the insulating shell 13.

[0203] The first fold line 1361 is spaced from the corresponding sides of the main fold piece 132 at opposite ends in its extension direction. Based on this, the first fold line 1361 can be made not to penetrate the main fold piece 132 in its extension direction, so that the main fold piece 132 and the transition corner 136 have a stronger connection strength in the area where the first fold line 1361 does not extend, and the connection strength, connection reliability and durability between the main fold piece 132 and the transition corner 136 can be maintained and improved, and the risk of cracks, splits and tears in the connection area between the main fold piece 132 and the transition corner 136 can be reduced, thereby improving the structural reliability and service life of the insulating shell 13.

[0204] The second fold line 1362 is spaced from the corresponding sides of the side fold piece 133 at the two opposite ends of the second fold line 1362 in the extension direction. Based on this, the second fold line 1362 does not penetrate the side fold piece 133 in the extension direction, and the side fold piece 133 and the transition corner 136 have a strong connection strength in the area where the second fold line 1362 does not extend, which can maintain and improve the connection strength, connection reliability and durability between the side fold piece 133 and the transition corner 136, and reduce the risk of cracks, splits and tears in the connection area between the side fold piece 133 and the transition corner 136, thereby improving the structural reliability and service life of the insulating shell 13.

[0205] The third fold line 1341 is disposed at opposite ends of its extension direction at intervals from the corresponding sides of the extension folded piece 134. Based on this, the third fold line 1341 can be made not to penetrate the extension folded piece 134 in its extension direction, so that the extension folded piece 134 and the base sheet 131 have a stronger connection strength in the area where the third fold line 1341 is not extended, and the connection strength, connection reliability and durability between the extension folded piece 134 and the base sheet 131 can be maintained and improved, and the risk of cracks, splits and tears in the connection area between the extension folded piece 134 and the base sheet 131 can be reduced, thereby improving the structural reliability and service life of the insulating shell 13.

[0206] The extension flap 134 is a rectangular structure. Based on this, the shape of the extension flap 134 can be regularized, and the extension flap 134 can have a regular and large surface area, can cover a wider area, and can reliably cover the gap between the corresponding side flap 133 and the base sheet 131, so as to optimize the covering effect of the extension flap 134 on the gap between the side flap 133 and the base sheet 131, and reduce the risk of the extension flap 134 missing the covering gap. In addition, the rectangular extension flap 134 is easy to process, fold and install.

[0207] See also Figure 2 , Figure 3 Some embodiments of the present application provide a battery 1, and the battery 1 includes a battery cell 10 provided in an embodiment of the present application.

[0208] By adopting the above solution, the battery 1 can improve the reliability and service life of each battery cell 10 by applying the battery cell 10 provided in the embodiment of the present application, thereby improving the reliability and service life of the battery 1.

[0209] See also Figure 1 , Figure 3 Some embodiments of the present application provide an electrical device, which includes a battery 1 provided in an embodiment of the present application, or a battery cell 10 provided in an embodiment of the present application.

[0210] By adopting the above solution, the electrical device can improve the reliability and service life of the electrical device by applying the battery 1 or the battery cell 10 provided in the embodiment of the present application.

[0211] The above description is only a preferred embodiment of the present application and is not intended to limit the present application. Any modifications, equivalent substitutions or improvements made within the spirit and principles of the present application should be included in the protection scope of the present application.

Claims

1. A battery cell, characterized in that: The battery cell comprises: shell; A battery cell group, contained in the housing, the battery cell group comprising one or more electrode assemblies arranged side by side; An insulating shell, comprising a base sheet, a main folding sheet, and a side folding sheet, wherein the base sheet supports the battery cell group, and two main folding sheets are provided and are respectively provided on opposite sides of the base sheet along a first direction to respectively cover opposite sides of the battery cell group along the first direction; the insulating shell has a first side along a second direction, and the second direction is perpendicular to the first direction; On the first side: at least one of the main folding pieces is connected to the side folding piece via a transition angle, the side folding piece covers the corresponding side of the battery cell group, the transition angle is connected to the main folding piece via a first fold line, and is connected to the side folding piece via a second fold line, the base sheet is connected to an extension folding piece via a third fold line, the third folding line is misaligned with the straight line where the first folding line is located in the unfolded state of the insulating shell, and / or misaligned with the straight line where the second folding line is located, the extension folding piece is folded to the corresponding side of the battery cell group, and covers the gap between the corresponding side folding piece and the base sheet.

2. The battery cell according to claim 1, characterized in that: The third fold line is located between the straight line where the first fold line is located and the straight line where the second fold line is located when the insulating shell is in the unfolded state.

3. The battery cell according to claim 1, characterized in that: The extension flap is folded to the outer side of the corresponding side flap.

4. The battery cell according to claim 1, characterized in that: On the first side, the two main folding sheets are connected to the side folding sheets via the transition angles, and the two side folding sheets jointly cover the corresponding sides of the battery cell group.

5. The battery cell according to claim 4, characterized in that: The extension flap is folded to the outer sides of the two side flaps.

6. The battery cell according to claim 4, characterized in that: The two side fold pieces are respectively a first side fold piece and a second side fold piece, and a portion of the first side fold piece is folded to the outside of the second side fold piece.

7. The battery cell according to claim 6, characterized in that: A first notch is disposed at a portion of the first side flap folded to the outside of the second side flap.

8. The battery cell according to claim 7, characterized in that: The extension flap is folded to the outside of the first side flap and the second side flap, or the extension flap is folded between the first side flap and the second side flap; The first notch is disposed at one end of the first side fold close to the extension fold, and a portion of the first notch is exposed outside the extension fold.

9. The battery cell according to claim 7, characterized in that: The first notch is disposed at a corner of the first side flap close to the extension flap.

10. The battery cell according to any one of claims 1 to 9, characterized in that: Along a direction perpendicular to the third fold line, a size of the extended flap ranges from 5 mm to 15 mm.

11. The battery cell according to any one of claims 1 to 9, characterized in that: A second notch is provided between the extension flap and the side flap adjacent thereto.

12. The battery cell according to any one of claims 1 to 9, characterized in that: At least one corner of the substrate is rounded.

13. The battery cell according to claim 12, characterized in that: The corner of the base sheet adjacent to the extension flap is a rounded corner; Along the first direction, the width of the extension flap is equal to the width of the base sheet minus the dimensions of two corners of the base sheet adjacent to the extension flap.

14. The battery cell according to claim 13, characterized in that: The extension flap, the corner of the base sheet disposed adjacent thereto, and the side flap disposed adjacent thereto enclose a second notch.

15. The battery cell according to any one of claims 1 to 9, characterized in that: The first fold line is spaced apart from a corresponding side of the main fold piece at at least one end of the first fold line in its extending direction.

16. The battery cell according to any one of claims 1 to 9, characterized in that: The second fold line is spaced apart from the corresponding side of the side fold piece at at least one end of the second fold line in its extending direction.

17. The battery cell according to any one of claims 1 to 9, characterized in that: The third fold line is spaced apart from a corresponding side of the extension flap at at least one end of the third fold line in its extension direction.

18. The battery cell according to any one of claims 1 to 9, characterized in that: The extended flap is a rectangular structure.

19. The battery cell according to any one of claims 1 to 9, characterized in that: The transition angle is a rounded angle.

20. A battery, characterized in that: The battery comprises the battery cell according to any one of claims 1 to 19.

21. An electrical device, characterized in that: The electrical device comprises the battery according to claim 20, or the battery cell according to any one of claims 1-19.

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