Battery cell, battery device and electrical device

Abstract

Provided in the present application are a battery cell, a battery device and an electrical device. The battery cell comprises a housing and an electrode assembly, the electrode assembly being accommodated in the housing. The electrode assembly comprises a first electrode sheet, a second electrode sheet, a solid-state electrolyte layer and an insulating member. The first electrode sheet comprises a first main body region and a first tab, the first tab being provided at one end of the first main body region in a first direction, the first tab comprising a folding portion and a connecting portion connected in sequence, the folding portion being connected to the folding portion of an adjacent first tab, and the connecting portion connecting the folding portion and the first main body region. The polarity of the second electrode sheet is opposite to that of the first electrode sheet. In the first direction, the end of the second electrode sheet close to the first tab is a first end. The solid-state electrolyte layer is provided between the first electrode sheet and the second electrode sheet in a second direction, the second direction intersecting the first direction. The provision of the insulating member reduces the risk of short circuits between the first electrode sheet and the second electrode sheet caused by overlapping between the connecting portion and the first end, thereby effectively improving the reliability of the battery cell.

Description

Battery cell, battery device and electric device Cross-reference to Related Applications

[0001] This application claims priority to Chinese Patent Application (2024112369383) entitled "Battery cell, battery device and electric device" filed on September 04, 2024, the entire contents of which are incorporated herein by reference. TECHNICAL FIELD

[0002] The present application relates to the technical field of battery, in particular to a battery cell, a battery device and an electric device. BACKGROUND

[0003] In recent years, new energy vehicles have made a leap in development. In the field of electric vehicles, power batteries, as the power source of electric vehicles, play an irreplaceable important role. With the vigorous promotion of new energy vehicles, the demand for power battery products is also increasing. With the increasing demand for batteries, higher requirements are placed on the reliability of battery cells. Therefore, how to improve the reliability of battery cells is a problem to be solved in battery technology. SUMMARY

[0004] The embodiments of the present application provide a battery cell, a battery device and an electric device, which can improve the reliability of the battery cell.

[0005] In a first aspect, the embodiments of the present application provide a battery cell, comprising a shell and an electrode assembly, the electrode assembly being accommodated in the shell; the electrode assembly comprises a first electrode sheet, a second electrode sheet, a solid-state electrolyte layer and an insulating piece; the first electrode sheet comprises a first main body region and a first tab, the first tab being arranged at one end of the first main body region along a first direction, the first tab comprising a folding part and a connecting part connected in sequence, the folding part being used to connect with the folding part of an adjacent first tab, and the connecting part connecting the folding part and the first main body region; the second electrode sheet is opposite in polarity to the first electrode sheet, and along the first direction, one end of the second electrode sheet close to the first tab is a first end; the solid-state electrolyte layer is arranged between the first electrode sheet and the second electrode sheet along a second direction, and the second direction intersects the first direction; and the insulating piece is arranged at least partially between the connecting part and the first end along the first direction to insulate and separate the connecting part and the second electrode sheet.

[0006] In the above technical solution, the insulating piece is arranged at least partially between the connecting part and the first end along the first direction, so that the connecting part of the first tab and the second electrode sheet can be insulated and separated by the insulating piece, thereby reducing the risk of short circuit of the first electrode sheet and the second electrode sheet caused by the lap joint of the connecting part and the first end, and effectively improving the reliability of the battery cell.

[0007] In some embodiments, the insulating member includes a first insulating member, the first insulating member is arranged at the connecting portion, and at least part of the first insulating member is located between the connecting portion and the first end in the first direction. By arranging the first insulating member at the connecting portion and locating at least part of the first insulating member between the connecting portion and the first end, the risk of the surface of the connecting portion facing the first end contacting the first end can be reduced, and stable insulation between the connecting portion and the second pole piece can be achieved. In addition, after the first pole piece is formed, the first insulating member can be arranged at the first tab first, and then the electrode assembly can be formed by the first pole piece, the second pole piece and the solid-state electrolyte layer, which can reduce the arrangement difficulty of the first insulating member.

[0008] In some embodiments, the connecting portion is bent to form a first connecting portion and a second connecting portion connected to each other, the first connecting portion is connected to the folding portion, the second connecting portion is connected to the first main body region, the first connecting portion is arranged opposite to the first end in the first direction, the first connecting portion has a first surface facing the first end, and at least part of the first insulating member is located between the first connecting portion and the first end and covers at least part of the first surface. The connecting portion is in a bent structure, and after the connecting portion is bent, the first connecting portion of the connecting portion is in an opposite state to the first end in the first direction, and the first surface of the first connecting portion facing the first end contacts the first end, which greatly increases the risk of short circuit of the first pole piece and the second pole piece. However, by arranging at least part of the first insulating member between the first connecting portion and the first end and covering at least part of the first surface, the risk of the first surface of the first connecting portion contacting the first end can be effectively reduced, and the risk of short circuit of the first pole piece and the second pole piece can be reduced.

[0009] In some embodiments, the second connecting portion has a second surface facing the second pole piece in the second direction, the second surface is connected to the first surface, and the first insulating member covers at least part of the second surface. In this way, the first insulating member can not only separate the first connecting portion and the second pole piece, but also separate the second connecting portion and the second pole piece, thereby reducing the risk of the second surface of the second connecting portion contacting the second pole piece and causing short circuit of the first pole piece and the second pole piece.

[0010] In some embodiments, the first main body region has a second end to which the first tab is connected in the first direction, and the solid-state electrolyte layer includes a first overhanging region beyond the second end; and a part of the first insulating member is located between the first overhanging region and the connecting portion in the second direction. In this way, the first insulating member has a longer dimension in the extension direction of the first tab, the coverage range of the surface of the connecting portion covered by the first insulating member is increased, and the first insulating member can better separate the connecting portion and the second pole piece, thereby reducing the risk of the connecting portion and the second pole piece being overlapped.

[0011] In some embodiments, along the second direction, the portion of the first insulating member between the first overhanging region and the connecting portion abuts against the first overhanging region and the connecting portion. The portion of the first insulating member between the first overhanging region and the connecting portion can function to support the first overhanging region and the connecting portion, so that the first overhanging region and the connecting portion are kept at a distance in the second direction, reducing the risk of the solid-state electrolyte layer being cracked or sheared by the edge of the first main body region at the second end during the forming of the electrode assembly.

[0012] In some embodiments, along the first direction, the first main body region has a second end, and the first tab is connected to the second end; the first insulating member comprises a first insulating portion, the first insulating portion is connected to the second end and extends along the extension direction of the first tab, and at least a portion of the first insulating portion is located between the connecting portion and the first end in the first direction. The length of the first insulating portion along the extension direction of the first tab is increased, which increases the coverage of the surface of the connecting portion by the first insulating portion, and reduces the risk of the connecting portion being overlapped with the second tab.

[0013] In some embodiments, along the second direction, the first tabs and the second tabs are arranged alternately, and the second tabs are one more than the first tabs; along the extension direction of the first tab, the length of the first insulating portion is H, and Q≤H≤2Q; N is an even number, and Q=M1×N / 2+M2×(N-1) / 2+M3×(N-1); or N is an odd number, and Q=M1×(N-1) / 2+M2×(N-1) / 2+M3×(N-1); wherein the number of the first tabs in the electrode assembly is N; the thickness of the first tab is M1, the thickness of the second tab is M2, and the thickness of the solid-state electrolyte layer is M3. The length of the first insulating portion is designed according to the number of the first tabs and the thicknesses of the first tab, the second tab, and the solid-state electrolyte layer, so that the first insulating portion has sufficient length, and a portion of the first insulating portion can extend between the connecting portion and the first end to effectively separate the connecting portion and the second tab in the first direction.

[0014] In some embodiments, the solid-state electrolyte layer comprises a first overhanging region beyond the second end; along the second direction, a portion of the first insulating portion is located between the first overhanging region and the connecting portion and abuts against the first overhanging region and the connecting portion. The first insulating portion is connected to the second end and a portion of the first insulating portion is located between the first overhanging region and the connecting portion, so that the first insulating portion can stably support the first overhanging region and the connecting portion, so that the first overhanging region and the connecting portion are kept at a distance in the second direction, reducing the risk of the solid-state electrolyte layer being cracked or sheared by the edge of the first main body region at the second end during the forming of the electrode assembly.

[0015] In some embodiments, the first insulation part includes a first portion and a second portion; the first portion is arranged at the connecting portion, at least part of the first portion is located between the connecting portion and the first end along the first direction; the second portion is connected with the first portion, the second portion is connected to the second end, the thickness of the second portion is greater than the thickness of the first portion, at least part of the second portion is located between the first overhanging area and the connecting portion along the second direction, and abuts against the first overhanging area and the connecting portion. The second portion with a larger thickness is arranged between the first overhanging area and the connecting portion, and the second portion can provide good support to the first overhanging area and the connecting portion in the second direction. The first portion with a smaller thickness is arranged at the connecting portion, and the first portion has better bending performance to adapt to the bending of the connecting portion. The first insulation part with such a structure can not only provide good support to the first overhanging area and the connecting portion, but also can bend together with the connecting portion, and can reduce the material of the first insulation part, and has better economy.

[0016] In some embodiments, along the first direction, the size of the second portion is d, and the size of the first overhanging area is D, and 0.1≤d / D≤1. d / D≥0.1 makes the ratio of the size of the second portion along the first direction to the size of the first overhanging area along the first direction not too small, so that the second portion can provide sufficient support to the first overhanging area and the connecting portion, and reduces the risk of the solid-state electrolyte layer being cracked or sheared during the forming process of the electrode assembly. d / D≤1 makes the ratio of the size of the second portion along the first direction to the size of the first overhanging area along the first direction not too large, which can reduce the material of the second portion and has better economy. Therefore, 0.1≤d / D≤1, which takes into account the support performance and economy of the second portion.

[0017] In some embodiments, 2mm≤d≤10mm. d≥2mm makes the size of the second portion along the first direction larger, which reduces the forming difficulty of the second portion and makes the second portion provide sufficient support to the first overhanging area and the connecting portion. d≤10mm makes the size of the second portion along the first direction not too large, which reduces material waste.

[0018] In some embodiments, the first insulation part further includes a second insulation part, the second insulation part is connected with the second portion, the thickness of the second insulation part is smaller than the thickness of the second portion, and the second insulation part is arranged in a stack with the first main area along the second direction. The second insulation part of the first insulation part is arranged in a stack with the first main area along the second direction, which on the one hand increases the total length of the first insulation part, further reduces the risk of the connecting portion overlapping the second tab, and on the other hand increases the contact area between the first insulation part and the first tab, so that the first insulation part is more stable on the first tab, to realize stable insulation between the connecting portion and the second tab. In addition, since the thickness of the second insulation part is smaller than the thickness of the second portion, the thickness of the second insulation part is not too large, which reduces the space occupied by the second insulation part in the second direction.

[0019] In some embodiments, the first insulating piece further comprises a second insulating portion, the second insulating portion is connected with the first insulating portion, and the second insulating portion is stacked with the first body region in the second direction. The second insulating portion of the first insulating piece is stacked with the first body region in the second direction, which on the one hand increases the total length of the first insulating piece, further reduces the risk of the connecting portion overlapping with the second tab, and on the other hand increases the contact area between the first insulating piece and the first tab, so that the first insulating piece is more firm on the first tab, so as to realize stable insulation between the connecting portion and the second tab.

[0020] In some embodiments, the first body region comprises a first current collector layer and a first active material layer; the first current collector layer is connected with the first tab; the first active material layer is located at the second end in the first direction close to one end of the first tab; in the second direction, the first current collector layer is provided with the first active material layer on the side facing the solid-state electrolyte layer, and the second insulating portion is stacked with the first active material layer. The first insulating piece plays a certain protective role on the edge region of the first active material layer close to the second end, reduces the risk of the edge region of the first active material layer separating from the first current collector layer, and can reduce the risk of the edge region of the first active material layer contacting the second tab.

[0021] In some embodiments, the first active material layer comprises a main body portion and a thinned portion; the thinned portion is provided at one end of the main body portion in the first direction close to the first tab, and the thickness of the thinned portion is less than the thickness of the main body portion; in the second direction, the second insulating portion is stacked with the thinned portion. In this way, the gap between the thinned portion and the solid-state electrolyte layer is fully utilized, which is conducive to the close adhesion of the main body portion of the first active material layer and the solid-state electrolyte layer, and reduces the interface impedance of the first tab and the solid-state electrolyte layer.

[0022] In some embodiments, the first body region comprises a first current collector layer, a first active material layer and an insulating layer; the first current collector layer is connected with the first tab; the insulating layer is provided at one end of the first active material layer in the first direction close to the first tab, and the one end of the insulating layer in the first direction close to the first tab is located at the second end; in the second direction, the first current collector layer is provided with the first active material layer and the insulating layer on the side facing the solid-state electrolyte layer, and the second insulating portion is stacked with the insulating layer. The setting of the insulating layer can reduce the risk of the burr of the edge region of the first current collector layer piercing the solid-state electrolyte layer and contacting the second tab. The second insulating portion is stacked with the insulating layer, and the second insulating portion can separate the first current collector layer and the second tab together, further reducing the risk of the burr of the edge region of the first current collector layer piercing the solid-state electrolyte layer and contacting the second tab.

[0023] In some embodiments, along the first direction, the size of the second insulation part is a, and the size of the first body area is A, 0.01≤a / A≤0.05. a / A≥0.01, so that the ratio of the size of the second insulation part along the first direction to the size of the first body area along the first direction is not too small, so that the second insulation part in the first insulation piece clamped by the first body area and the solid electrolyte layer has sufficient length, so that the first insulation piece is more firm on the first tab. a / A≤0.05, so that the ratio of the size of the second insulation part along the first direction to the size of the first body area along the first direction is not too large, on the one hand, the use of the second insulation part can be reduced, and better economy is achieved; on the other hand, the risk of the active material layer in the first body area being shielded by the second insulation part in a large area can be reduced.

[0024] In some embodiments, 0.05mm≤a≤5mm. a≥0.05mm, so that the second insulation part has sufficient length to facilitate the arrangement of the second insulation part on the surface of the first body area. a≤5mm, so that the second insulation part is not too long, reducing the use of the second insulation part and achieving better economy.

[0025] In some embodiments, along the second direction, the size of the second insulation part is b, and the size of the first body area is B, 0.05≤b / B≤0.25. b / B≥0.05, so that the ratio of the size of the second insulation part along the second direction to the size of the first body area along the second direction is not too small, so that the second insulation part has sufficient strength. b / B≤0.25, so that the ratio of the size of the second insulation part along the second direction to the size of the first body area along the second direction is not too large, reducing the thickness proportion of the second insulation part in the first body area, leaving more space for the active material layer in the first body area, which is beneficial to improve the volume energy density of the battery cell.

[0026] In some embodiments, 0.01mm≤b≤0.1mm. b≥0.01mm, so that the second insulation part has sufficient thickness to improve the strength of the second insulation part. b≤0.1mm, so that the second insulation part is not too thick, reducing the use of the second insulation part and achieving better economy.

[0027] In some embodiments, the electrode assembly includes a plurality of first tabs arranged along the second direction, and a second tab is arranged between adjacent two first tabs; the gathering parts of the plurality of first tabs are connected to form a gathering area, the plurality of first tabs includes two adjacent third tabs, and the second tab between the two third tabs is arranged opposite to the gathering area along the first direction, and the projection of the first insulation piece arranged between the two third tabs along the first direction collectively covers the first end of the second tab between the two third tabs. The risk of the connection part of the two third tabs overlapping the first end of the second tab between the two third tabs is reduced.

[0028] In some embodiments, the plurality of first pole pieces further comprises a fourth pole piece arranged along the second direction with the third pole piece; the first insulating member arranged on the fourth pole piece covers the first end of the second pole piece adjacent to the fourth pole piece and located on the side of the fourth pole piece close to the folding area in the projection along the first direction. Since the fourth pole piece is arranged along the second direction with the third pole piece, at least part of the connecting portion of the first lug of the fourth pole piece will extend obliquely towards the third pole piece, and the connecting portion of the first lug of the fourth pole piece is more likely to be overlapped with the first end of the second pole piece adjacent to the fourth pole piece and located on the side of the fourth pole piece close to the folding area. Since the first insulating member arranged on the fourth pole piece covers the first end of the second pole piece adjacent to the fourth pole piece and located on the side of the fourth pole piece close to the folding area in the projection along the first direction, the risk of the connecting portion of the first lug of the fourth pole piece being overlapped with the first end of the second pole piece adjacent to the fourth pole piece and located on the side of the fourth pole piece close to the folding area is effectively reduced.

[0029] In some embodiments, along the second direction, the opposite surfaces of the second pole piece are respectively provided with two solid-state electrolyte layers; in the projection plane perpendicular to the first direction, the orthographic projection of the two solid-state electrolyte layers partially overlaps with the orthographic projection of the first insulating member arranged on the fourth pole piece. The projection of the first insulating member arranged on the fourth pole piece in the first direction can cover not only the second pole piece but also the solid-state electrolyte layers on both sides of the second pole piece, thereby reducing the risk of the connecting portion of the first lug of the fourth pole piece being overlapped with the adjacent second pole piece.

[0030] In some embodiments, along the third direction, the first insulating member exceeds at least one edge of the first lug, and the first direction, the second direction and the third direction are not coplanar and intersect with each other. The size of the first insulating member in the third direction is increased, thereby reducing the risk of the connecting portion being overlapped with the second pole piece.

[0031] In some embodiments, along the third direction, the first insulating member exceeds the opposite two edges of the first lug. The size of the first insulating member in the third direction is further increased, and the first insulating member can cover more areas of the surface of the connecting portion along the third direction, thereby reducing the risk of the connecting portion being overlapped with the second pole piece.

[0032] In some embodiments, along the third direction, the size of the first insulating member is greater than the size of the first lug. The first insulating member has a certain redundancy in the third direction, which is conducive to the first insulating member being arranged on the connecting portion to cover more areas of the surface of the connecting portion.

[0033] In some embodiments, the insulating member comprises a second insulating member, and the first insulating member and the second insulating member are respectively arranged on both sides of the first lug in the thickness direction. The arrangement of the second insulating member makes more surfaces of the first lug covered, thereby further reducing the risk of the first lug being overlapped with the second pole piece.

[0034] In some embodiments, the first insulating member and the second insulating member both extend beyond at least one edge of the first tab in a third direction, the first direction, the second direction and the third direction are not coplanar and intersect with each other in pairs; wherein the portions of the first insulating member and the second insulating member extending beyond the same edge of the first tab are connected to each other in the third direction. In this way, the first insulating member is more firmly arranged on the first tab, and the risk of the first insulating member being separated from the first tab is reduced. In addition, the first insulating member and the second insulating member are in a state of covering the first tab as a whole, which can further reduce the risk of the connecting portion of the first tab being overlapped with the second tab.

[0035] In some embodiments, the first insulating member is an insulating tape arranged on the first tab. The first insulating member of this structure has low manufacturing cost and is easy to connect to the first tab.

[0036] In some embodiments, the first insulating member is an insulating coating arranged on the first tab. The first insulating member of this structure has high connection strength with the first tab, and the first insulating member is not easy to be separated from the first tab.

[0037] In some embodiments, the insulating member includes a third insulating member arranged on the second tab, and at least part of the third insulating member is arranged between the connecting portion and the first end in the first direction. By arranging the third insulating member on the second tab and at least partially between the connecting portion and the first end, the risk of the connecting portion being overlapped with the second tab can be reduced, and stable insulation between the connecting portion and the second tab can be achieved. In addition, the third insulating member is not easy to affect the bending of the first tab.

[0038] In some embodiments, the third insulating member completely covers the first end. The area of the third insulating member covering the first end is increased, and the risk of the connecting portion being overlapped with the second tab is reduced.

[0039] In some embodiments, the second tab is provided with two solid-state electrolyte layers respectively on two opposite surfaces thereof in the second direction; and in a projection plane perpendicular to the first direction, the projection of the two solid-state electrolyte layers partially overlaps with the projection of the third insulating member. The coverage range of the third insulating member is increased, and the risk of the connecting portion being overlapped with the second tab is reduced.

[0040] In some embodiments, the third insulating member is an insulating coating arranged on the first end. The third insulating member of this structure has high connection strength with the second tab, and the third insulating member is not easy to be separated from the second tab.

[0041] In some embodiments, the electrode assembly includes a plurality of second tabs arranged along the second direction, a first tab is arranged between any two adjacent second tabs, a third insulating member covers the first ends of the plurality of second tabs, the third insulating member is provided with a plurality of hollow regions, and the connecting portion of each first tab is arranged in a corresponding hollow region. The hollow regions of the third insulating member can allow the first tabs to pass through, which facilitates the connection of the first tabs with other components. One third insulating member can achieve the insulation isolation of the plurality of second tabs and the corresponding first tabs, which can effectively improve the arrangement efficiency of the third insulating member.

[0042] In some embodiments, the hollow region includes a through hole penetrating through the third insulating member along the first direction. By arranging the through hole on the third insulating member, the first tabs can be conveniently passed through, and the first end can be covered in a large area.

[0043] In some embodiments, along the first direction, the first main body region has a second end, the first tab is connected to the second end, the second tab includes a second overhanging region beyond the second end, the second overhanging region faces the first end of the one end of the connecting portion, and in a projection plane perpendicular to the second direction, the orthographic projection of the second overhanging region partially overlaps the orthographic projection of the solid-state electrolyte layer. In this way, the size of the solid-state electrolyte layer along the first direction can be increased, so that the solid-state electrolyte layer has a better separation effect between the first tab and the second tab.

[0044] In some embodiments, the electrode assembly is a laminated structure, and the electrode assembly includes a plurality of first tabs and a plurality of second tabs, and the plurality of first tabs and the plurality of second tabs are arranged in a laminated manner along the second direction. The electrode assembly is a laminated electrode assembly, which can achieve higher volumetric energy density and has better thermal stability.

[0045] In a second aspect, the embodiments of the present application provide a battery device, which includes the battery monomer provided by any one of the embodiments of the first aspect.

[0046] In a third aspect, the embodiments of the present application provide a power consumption device, which includes the battery monomer provided by any one of the embodiments of the first aspect or the battery device provided by any one of the embodiments of the second aspect, and the battery monomer is used to provide electric energy. BRIEF DESCRIPTION OF DRAWINGS

[0047] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the following will briefly introduce the drawings needed to be used in the embodiments. It should be understood that the following drawings only show some embodiments of the present application, and therefore should not be regarded as a limitation on the scope. For those skilled in the art, other related drawings can also be obtained without creative labor on the basis of these drawings.

[0048] FIG. 1 is a structural schematic diagram of a vehicle provided by some embodiments of the present application;

[0049] FIG. 2 is an exploded view of a battery device according to some embodiments of the present application;

[0050] FIG. 3 is an exploded view of a battery cell according to some embodiments of the present application;

[0051] FIG. 4 is an axonometric view of the battery cell shown in FIG. 3;

[0052] FIG. 5 is an A-A sectional view of the battery cell shown in FIG. 4;

[0053] FIG. 6 is a structural schematic view of an electrode assembly according to some embodiments of the present application;

[0054] FIG. 7 is an enlarged view of a portion B in FIG. 6;

[0055] FIG. 8 is a partial view of a first electrode tab shown in FIG. 6;

[0056] FIG. 9 is a structural view of the first electrode tab shown in FIG. 7;

[0057] FIG. 10 is a structural schematic view of a second electrode tab shown in FIG. 7;

[0058] FIG. 11 is a partial view of an electrode assembly according to some embodiments of the present application;

[0059] FIG. 12 is a partial view of an electrode assembly according to other embodiments of the present application;

[0060] FIG. 13 is a structural schematic view of a first insulating member shown in FIG. 12;

[0061] FIG. 14 is a partial view of an electrode assembly according to yet other embodiments of the present application;

[0062] FIG. 15 is a structural schematic view of a first insulating member shown in FIG. 14;

[0063] FIG. 16 is a connection schematic view of the first insulating member and the first electrode tab shown in FIG. 14;

[0064] FIG. 17 is a partial view of an electrode assembly according to still other embodiments of the present application;

[0065] FIG. 18 is a connection schematic view of the first insulating member and the first electrode tab shown in FIG. 17;

[0066] FIG. 19 is a partial view of a top region of the electrode assembly shown in FIG. 6;

[0067] FIG. 20 is a connection schematic view of the first electrode tab and the first insulating member according to some embodiments of the present application;

[0068] FIG. 21 is a partial view of an electrode assembly according to other embodiments of the present application;

[0069] Figure 22 is a schematic diagram of the structure of an electrode assembly provided in some other embodiments of this application;

[0070] Figure 23 is a magnified view of a portion of point C in Figure 22;

[0071] Figure 24 is a schematic diagram of the structure of an electrode assembly provided in some embodiments of this application;

[0072] Figure 25 is a magnified view of part D in Figure 24;

[0073] Figure 26 is a cross-sectional view of the third insulating component shown in Figure 25;

[0074] Figure 27 is a view of the third insulating component shown in Figure 26 from direction E;

[0075] Figure 28 is a schematic diagram of the structure of an electrode assembly provided in some embodiments of this application;

[0076] Figure 29 is a magnified view of part F in Figure 28.

[0077] Icons: 1-Outer shell; 11-Housing shell; 12-End cap; 2-Electrode assembly; 21-First electrode; 211-First main body region; 2111-Second end; 2112-First active material layer; 21121-Main body portion; 21122-Thinned portion; 2113-First current collector layer; 2114-Insulating layer; 212-First electrode tab; 2121-Connecting portion; 21211-First connecting portion; 21211a-First surface; 21212-Second connecting portion; 21212a-Second surface; 2122-Converging portion; 2123-First edge; 2124-Second edge; 22-Second electrode; 221-Second main body region; 2211-First end; 2212-Second active material layer; 2213-Second electrode; 2124-Second edge; 22-Second electrode; 221-Second main body region; 2211-First end; 2212-Second active material layer; 2213-Second electrode; 2121-Second active material layer; 2212-Second active material layer; 2213-Second active material layer; 21 ... Current collector layer; 2214-Second overrun area; 222-Second electrode tab; 23-Solid electrolyte layer; 231-First overrun area; 24-Insulator; 241-First insulating component; 2411-First insulating part; 24111-First section; 24112-Second section; 2412-Second insulating part; 242-Second insulating component; 243-Third insulating component; 2431-Hollowed-out area; 25-Collapsing area; 26-Third electrode; 27-Fourth electrode; 3-Electrode terminal; 10-Battery cell; 20-Casing; 201-First casing; 202-Second casing; 100-Battery assembly; 200-Controller; 300-Motor; 1000-Vehicle; Z-First direction; Y-Second direction; X-Third direction. Detailed Implementation

[0078] In order to make the objects, technical solutions and advantages of the embodiments of the present application clearer, the technical solutions in the embodiments of the present application will be described clearly below with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are only some of the embodiments of the present application, rather than all the embodiments of the present application. Based on the embodiments in the present application, all other embodiments obtained by a person of ordinary skill in the art without creative work fall within the protection scope of the present application.

[0079] Unless otherwise defined, all technical and scientific terms used in the present application have the same meaning as commonly understood by one of ordinary skill in the art to which the present application belongs; the terms used in the present application are only for the purpose of describing specific embodiments and are not intended to limit the present application; the terms "include" and "have" and any variations thereof in the description of the present application and the claims and the above description of drawings are intended to cover non-exclusive inclusion. The terms "first", "second" and the like in the description of the present application and the claims or the above description of drawings are used to distinguish different objects, rather than to describe a particular order or primary and secondary relationship.

[0080] In the present application, the phrase "embodiments" means that the specific features, structures or characteristics described in connection with the embodiments can be included in at least one embodiment of the present application. The phrase appears at various places in the specification does not necessarily all refer to the same embodiments, nor are they necessarily mutually exclusive or alternative embodiments to each other.

[0081] In the present application, the term "and / or" is only a description of the association relationship between the associated objects, which means that there can be three relationships, for example, A and / or B, which can represent the three cases of A alone, A and B together, and B alone. In addition, the character " / " in the present application generally represents an "or" relationship between the front and rear associated objects.

[0082] In the embodiments of the present application, the same reference signs represent the same components, and for the sake of brevity, detailed description of the same components is omitted in different embodiments. It should be understood that the thickness, length, width and other dimensions of various components in the embodiments of the present application shown in the drawings, as well as the overall thickness, length, width and other dimensions of the integrated device, are only exemplary and should not constitute any limitation on the present application.

[0083] "Multiple" appearing in the present application means two or more (including two).

[0084] In the embodiments of the present application, the battery cell can be a secondary battery, which refers to a battery cell that can be activated by charging after discharging.

[0085] The battery cell includes, but is not limited to, a lithium-ion battery, a sodium-ion battery, a sodium-lithium-ion battery, a lithium-metal battery, a sodium-metal battery, a lithium-sulfur battery, a magnesium-ion battery, a nickel-hydrogen battery, a nickel-cadmium battery, a lead-acid battery, and the like.

[0086] The battery cell generally includes an electrode assembly. The electrode assembly includes a positive electrode, a negative electrode, and a separator. During charging and discharging of the battery cell, active ions (e.g., lithium ions) are intercalated and deintercalated between the positive electrode and the negative electrode. The separator is disposed between the positive electrode and the negative electrode and can serve to reduce the risk of short circuiting between the positive electrode and the negative electrode while allowing the active ions to pass through.

[0087] In some embodiments, the positive electrode can be a positive electrode tab, which can include a positive electrode current collector and a positive electrode active material disposed on at least one surface of the positive electrode current collector.

[0088] As an example, the positive electrode current collector has two surfaces opposite in the thickness direction thereof, and the positive electrode active material is disposed on either one or both of the two opposite surfaces of the positive electrode current collector.

[0089] As an example, the positive electrode current collector can be a metal foil or a composite current collector. For example, as the metal foil, aluminum with a silver-plated surface, stainless steel with a silver-plated surface, stainless steel, copper, aluminum, nickel, or titanium, or the like can be used. The composite current collector can include a polymer material base layer and a metal layer. The composite current collector can be formed by forming a metal material (aluminum, aluminum alloy, nickel, nickel alloy, titanium, titanium alloy, silver, and silver alloy, or the like) on a polymer material base material (e.g., a base material of polypropylene, polyethylene terephthalate, polybutylene terephthalate, polystyrene, polyethylene, or the like).

[0090] As an example, the positive electrode active material can include at least one of a lithium-containing phosphate, a lithium transition metal oxide, and a modified compound of each thereof. However, the present application is not limited to these materials, and other conventional materials that can be used as a battery positive electrode active material can also be used. These positive electrode active materials can be used alone or in combination with two or more. Examples of the lithium-containing phosphate can include, but are not limited to, at least one of lithium iron phosphate (e.g., LiFePO4 (which can also be referred to as LFP)), a composite material of lithium iron phosphate and carbon, lithium manganese phosphate (e.g., LiMnPO4), a composite material of lithium manganese phosphate and carbon, lithium manganese iron phosphate, and a composite material of lithium manganese iron phosphate and carbon. Examples of the lithium transition metal oxide can include, but are not limited to, at least one of lithium cobalt oxide (e.g., LiCoO2), lithium nickel oxide (e.g., LiNiO2), lithium manganese oxide (e.g., LiMnO2, LiMn2O4), lithium nickel cobalt oxide, lithium manganese cobalt oxide, lithium nickel manganese oxide, lithium nickel cobalt manganese oxide (e.g., LiNi 1 / 3 Co 1 / 3 Mn 1 / 3 O2 (which can also be referred to as NCM333 LiNi0.5Mn1.5O4, 0.5 LiNi0.5Mn1.5O4, 0.2 LiNi0.5Mn1.5O4, 0.3 LiNi0.5Mn1.5O4, 523 LiNi0.5Mn1.5O4, 0.5 LiNi0.5Mn1.5O4, 0.25 LiNi0.5Mn1.5O4, 0.25 LiNi0.5Mn1.5O4, 211 LiNi0.5Mn1.5O4, 0.6 LiNi0.5Mn1.5O4, 0.2 LiNi0.5Mn1.5O4, 0.2 LiNi0.5Mn1.5O4, 622 LiNi0.5Mn1.5O4, 0.7 LiNi0.5Mn1.5O4, 0.1 LiNi0.5Mn1.5O4, 0.1 LiNi0.5Mn1.5O4, 711 LiNi0.5Mn1.5O4, 0.8 LiNi0.5Mn1.5O4, 0.1 LiNi0.5Mn1.5O4, 0.1 LiNi0.5Mn1.5O4, 811 LiNi0.5Mn1.5O4, 0.85 LiNi0.5Mn1.5O4, 0.15 LiNi0.5Mn1.5O4, 0.05 LiNi0.5Mn1.5O4,

[0091] In some embodiments, the positive electrode can employ a foam metal. The foam metal can be a foam nickel, a foam copper, a foam aluminum, a foam alloy, or the like. When the foam metal is employed as the positive electrode, the surface of the foam metal can not be provided with the positive electrode active material, or of course can be provided with the positive electrode active material. As an example, the foam metal can be filled or / and deposited with a lithium source material, a potassium metal, or a sodium metal, the lithium source material being a lithium metal and / or a lithium-rich material.

[0092] In some embodiments, the negative electrode can be a negative electrode tab, which can include a negative electrode current collector.

[0093] As an example, the negative electrode current collector can employ a metal foil, a foam metal, or a composite current collector. For example, as the metal foil, an aluminum with a silver plating treatment on the surface, a stainless steel with a silver plating treatment on the surface, a stainless steel, a copper, an aluminum, a nickel, or a titanium, or the like can be employed. The foam metal can be a foam nickel, a foam copper, a foam aluminum, a foam alloy, or the like. The composite current collector can include a polymer material base layer and a metal layer. The composite current collector can be formed by forming a metal material (copper, copper alloy, nickel, nickel alloy, titanium, titanium alloy, silver, and silver alloy, or the like) on a polymer material base material (such as a base material of polypropylene, polyethylene terephthalate, polybutylene terephthalate, polystyrene, polyethylene, or the like).

[0094] As an example, the negative electrode tab can include the negative electrode current collector and the negative electrode active material provided on at least one surface of the negative electrode current collector.

[0095] As an example, the negative current collector has two surfaces opposite in the thickness direction thereof, and the negative active material is provided on either one or both of the two surfaces of the negative current collector.

[0096] As an example, the negative active material can employ a negative active material for a battery cell known in the art. As an example, the negative active material can include at least one of artificial graphite, natural graphite, soft carbon, hard carbon, a silicon-based material, a tin-based material, and lithium titanate, etc. The silicon-based material can be selected from at least one of elemental silicon, a silicon oxide compound, a silicon-carbon composite, a silicon-nitrogen composite, and a silicon alloy. The tin-based material can be selected from at least one of elemental tin, a tin oxide compound, and a tin alloy. However, the present application is not limited to these materials, and other conventional materials that can be used as a battery negative active material can also be used. These negative active materials can be used alone only one or in combination of two or more.

[0097] In some embodiments, the material of the positive current collector can be aluminum, and the material of the negative current collector can be copper.

[0098] In some embodiments, the separator is a solid-state electrolyte layer. The solid-state electrolyte layer is disposed between the positive electrode and the negative electrode, and functions to transport ions and separate the positive electrode and the negative electrode.

[0099] The solid-state electrolyte layer includes a polymer solid-state electrolyte, an inorganic solid-state electrolyte, and a composite solid-state electrolyte.

[0100] As an example, the polymer solid-state electrolyte can be a polyether (polyethylene oxide), a polysiloxane, a polycarbonate, a polyacrylonitrile, a polyvinylidene fluoride, a polymethyl methacrylate, a single-ion polymer, a polyionic liquid-lithium salt, cellulose, etc.

[0101] As an example, the inorganic solid-state electrolyte can include one or more of an oxide solid electrolyte (crystalline perovskite, sodium superionic conductor, garnet, amorphous LiPON thin film), a sulfide solid electrolyte (crystalline lithium superionic conductor (lithium germanium phosphorus sulfide, argyrodite), amorphous sulfide), a halide solid electrolyte, a nitride solid electrolyte, and a hydride solid electrolyte.

[0102] As an example, the composite solid-state electrolyte is formed by adding an inorganic solid-state electrolyte filler to a polymer solid-state electrolyte.

[0103] In some embodiments, the electrode assembly is provided with a tab, and the tab can lead current out of the electrode assembly. The tab includes a positive tab and a negative tab.

[0104] In some embodiments, the battery cell can include a casing. The casing is used to encapsulate components such as the electrode assembly. The casing can be a steel casing, an aluminum casing, a plastic casing (such as polypropylene), a composite metal casing (such as a copper-aluminum composite casing), or an aluminum-plastic film, etc.

[0105] As an example, the battery cell can be a cylindrical battery cell, a prismatic battery cell, a pouch battery cell, or a battery cell of other shapes, the prismatic battery cell including a square battery cell, a blade battery cell, a multi-prismatic battery cell, such as a hexagonal battery cell, etc.

[0106] The battery apparatus mentioned in the embodiments of the present application can include one or more battery cell assemblies for providing voltage and capacity. The battery cell assembly can include a plurality of battery cells connected in series, in parallel, or in a mixed connection through a busbar component.

[0107] In some embodiments, the battery cell assembly is generally formed by arranging a plurality of battery cells; as an example, the battery cell assembly can be a battery module formed by arranging and fixing a plurality of battery cells into an independent module.

[0108] As an example, the battery module can be formed by bundling a plurality of battery cells with a cable tie.

[0109] In some embodiments, the battery apparatus can be a battery pack including a box and one or more battery cell assemblies accommodated in the box.

[0110] As an example, the battery cell assembly can be a battery module, and the battery cell assembly can be accommodated in the box by fixing the battery module in the box.

[0111] As an example, the battery cell assembly can also be accommodated in the box by directly fixing a plurality of battery cells in the box.

[0112] As an example, the box can include a first box and a second box. The first box and the second box are buckled so that a closed space is formed inside the box to accommodate the battery cell assembly. Here, closed means covered or closed, which can be sealed or unsealed. The first box can be a top cover or a bottom plate.

[0113] As an example, the box can include a top cover, a frame, and a bottom plate. The top cover and the bottom plate are respectively connected with the frame so that a closed space is formed inside the box to accommodate the battery cell assembly.

[0114] As an example, the box can be part of a chassis structure of a vehicle. For example, the top cover of the box can be at least part of a floor of the vehicle, or the frame of the box can be at least part of a cross beam and a longitudinal beam of the vehicle.

[0115] In some embodiments, the battery device refers to an energy storage device, and the energy storage device includes a box, at least one side of the box is provided with a door. The energy storage device includes an energy storage container, an energy storage cabinet, etc.

[0116] For a general battery monomer, the battery monomer can include a shell and an electrode assembly, and the electrode assembly and an electrolyte are contained in the shell. The electrode assembly can include a first pole piece, a separation film, and a second pole piece, the polarities of the first pole piece and the second pole piece are opposite, and the separation film is arranged between the first pole piece and the second pole piece to separate the first pole piece and the second pole piece. The tabs of the first pole piece and the second pole piece are generally in a bent state, in order to reduce the risk of the tab being overlapped with the end of the pole piece with opposite polarity, the separation film can be bent to the end of the pole piece to insulate and separate the tab and the pole piece with opposite polarity.

[0117] In a solid-state battery monomer, the solid-state electrolyte layer plays a separating role between the first pole piece and the second pole piece. The solid-state electrolyte layer is generally difficult to bend to the end of the pole piece, and the tab in the bent state is easy to be overlapped with the end of the pole piece with opposite polarity, causing the first pole piece to be short-circuited with the second pole piece, affecting the reliability of the battery monomer.

[0118] In view of this, the embodiments of the present application provide a battery monomer, which includes a shell and an electrode assembly, and the electrode assembly is contained in the shell; the electrode assembly includes a first pole piece, a second pole piece, a solid-state electrolyte layer, and an insulating piece. The first pole piece includes a first main body region and a first tab, the first tab is arranged at one end of the first main body region along a first direction, the first tab includes a folding part and a connecting part connected in sequence, the folding part is used to connect with the folding part of an adjacent first tab, and the connecting part connects the folding part and the first main body region. The second pole piece is opposite to the first pole piece in polarity, and along the first direction, one end of the second pole piece close to the first tab is a first end. The solid-state electrolyte layer is arranged between the first pole piece and the second pole piece along a second direction, and the second direction intersects the first direction. The insulating piece is arranged at least partially between the connecting part and the first end along the first direction to insulate and separate the connecting part and the second pole piece.

[0119] In such a battery monomer, the insulating piece is arranged at least partially between the connecting part and the first end along the first direction, and the connecting part of the first tab and the second pole piece can be insulated and separated by the insulating piece, thereby reducing the risk of the connecting part being overlapped with the first end to cause the first pole piece to be short-circuited with the second pole piece, and effectively improving the reliability of the battery monomer.

[0120] The battery cell described in the embodiments of the present application is applicable to various electric devices using battery cells and battery devices, such as mobile phones, portable devices, notebook computers, electric vehicles, electric toys, electric tools, vehicles, ships and spacecraft, such as aircraft, rockets, space shuttles and spaceships.

[0121] The following embodiments are described by taking the electric device as a vehicle for example for convenience of description.

[0122] Please refer to FIG. 1, which is a structural schematic diagram of a vehicle 1000 provided by some embodiments of the present application. The vehicle 1000 is internally provided with a battery device 100, which can be arranged at the bottom, head or tail of the vehicle 1000. The battery device 100 can be used for power supply of the vehicle 1000, for example, the battery device 100 can be used as the operating power supply of the vehicle 1000.

[0123] The vehicle 1000 can further include a controller 200 and a motor 300, the controller 200 being used to control the battery device 100 to supply power to the motor 300, for example, to meet the power demand of the vehicle 1000 during starting, navigation and driving.

[0124] In some embodiments of the present application, the battery device 100 can not only be used as the operating power supply of the vehicle 1000, but also be used as the driving power supply of the vehicle 1000, replacing or partially replacing fuel or natural gas to provide driving power for the vehicle 1000.

[0125] Please refer to FIG. 2, which is an exploded view of the battery device 100 provided by some embodiments of the present application. The battery device 100 can include a battery cell 10 and a box 20, the box 20 being used to accommodate the battery cell 10.

[0126] The box 20 is internally formed with a closed space for accommodating the battery cell 10, and the box 20 can adopt various structures. In some embodiments, the box 20 can include a first box 201 and a second box 202, the first box 201 being buckled with the second box 202. The first box 201 and the second box 202 can be various shapes, such as cuboid, cylinder and the like. The first box 201 can be a hollow structure with one side open, and the second box 202 can also be a hollow structure with one side open. The open side of the second box 202 is buckled with the open side of the first box 201, thereby forming the box 20 with a closed space. Alternatively, the first box 201 can be a hollow structure with one side open, and the second box 202 can be a plate structure, the second box 202 being buckled at the open side of the first box 201, thereby forming the box 20 with an accommodation space.

[0127] In the battery device 100, the battery cell 10 can be one or multiple. If the battery cell 10 is multiple, the multiple battery cells 10 can be connected in series, in parallel, or in a mixed connection, where the mixed connection means that the multiple battery cells 10 are connected in series and in parallel. The multiple battery cells 10 can be connected in series, in parallel, or in a mixed connection to form a battery module, and the multiple battery modules can be connected in series, in parallel, or in a mixed connection to form a whole, which is accommodated in the box 20. Alternatively, all the battery cells 10 can be directly connected in series, in parallel, or in a mixed connection, and the whole formed by the battery cells 10 is accommodated in the box 20.

[0128] Please refer to FIG. 3-FIG. 5, FIG. 3 is an exploded view of the battery cell 10 provided by some embodiments of the present application; FIG. 4 is an axonometric view of the battery cell 10 shown in FIG. 3; and FIG. 5 is an A-A sectional view of the battery cell 10 shown in FIG. 4. The battery cell 10 can include a shell 1 and an electrode assembly 2, and the electrode assembly 2 is accommodated in the shell 1.

[0129] In some embodiments, the shell 1 can include a casing 11 and an end cover 12, the casing 11 has an opening, and the end cover 12 closes the opening of the casing 11. Here, closing means covering or closing, which can be sealed or unsealed.

[0130] The casing 11 is a component for accommodating the electrode assembly 2, and the casing 11 can be a hollow structure with an opening at one end, or a hollow structure with openings at opposite ends. The casing 11 can have various shapes, such as a cylindrical shape, a cuboid shape, etc. The material of the casing 11 can be various, such as copper, iron, aluminum, steel, aluminum alloy, etc. The electrode assembly 2 can be partially located in the casing 11, or entirely located in the casing 11.

[0131] The end cover 12 cooperates with the casing 11 to define a receiving space for accommodating the electrode assembly 2 and other components. The end cover 12 can be connected to the casing 11 by welding, crimping, etc., to close the opening of the casing 11. The shape of the end cover 12 can be adapted to the shape of the casing 11, such as the casing 11 being a cuboid structure and the end cover 12 being a rectangular plate structure adapted to the casing 11, or the casing 11 being a cylindrical structure and the end cover 12 being a circular plate structure adapted to the casing 11. The material of the end cover 12 can also be various, such as copper, iron, aluminum, steel, aluminum alloy, etc., and the material of the end cover 12 and the casing 11 can be the same or different.

[0132] In the embodiment where the casing 11 has an opening at one end, one end cover 12 can be correspondingly provided. In the embodiment where the casing 11 has openings at opposite ends, two end covers 12 can be correspondingly provided, and the two end covers 12 close the two openings of the casing 11 respectively, and the two end covers 12 and the casing 11 cooperatively define the receiving space.

[0133] In some embodiments, the battery cell 10 can further include electrode terminals 3 disposed on the outer shell 1, the electrode terminals 3 being electrically connected to the tabs of the electrode assembly 2 to input or output the electric energy of the battery cell 10. The electrode terminals 3 can be disposed on the housing 11 of the outer shell 1 or on the end cover 12 of the outer shell 1. The electrode terminals 3 can be directly connected to the tabs, for example, the electrode terminals 3 are welded to the tabs. The electrode terminals 3 can also be indirectly connected to the tabs, for example, the electrode terminals 3 are indirectly connected to the tabs through current collecting members. The current collecting members can be metal conductors, for example, copper, iron, aluminum, steel, aluminum alloy, etc.

[0134] As an example, as shown in FIGS. 3-5, the housing 11 has an opening at one end, and the outer shell 1 has one end cover 12, and one end cover 12 closes one opening of the housing 11. The end cover 12 is provided with two electrode terminals 3, and the two electrode terminals 3 are respectively a positive electrode terminal and a negative electrode terminal. The electrode assembly 2 has a positive tab and a negative tab formed at one end facing the end cover 12, and the positive electrode terminal is electrically connected to the positive tab, and the negative electrode terminal is electrically connected to the negative tab.

[0135] Please refer to FIGS. 6-10, FIG. 6 is a structural schematic diagram of the electrode assembly 2 provided by some embodiments of the present application; FIG. 7 is a partial enlarged view of B in FIG. 6; FIG. 8 is a partial view of the first tab 21 shown in FIG. 6; FIG. 9 is a structural view of the first tab 21 shown in FIG. 7; and FIG. 10 is a structural schematic diagram of the second tab 22 shown in FIG. 7. The present application provides a battery cell 10, which includes an outer shell 1 and an electrode assembly 2, and the electrode assembly 2 is contained in the outer shell 1. The electrode assembly 2 includes a first tab 21, a second tab 22, a solid-state electrolyte layer 23, and an insulating member 24. The first tab 21 includes a first main body region 211 and a first tab 212, and the first tab 212 is disposed at one end of the first main body region 211 along a first direction Z. The first tab 212 includes a folding portion 2122 and a connecting portion 2121 connected in sequence, the folding portion 2122 is used to connect the folding portion 2122 of the adjacent first tab 212, and the connecting portion 2121 connects the folding portion 2122 and the first main body region 211. The second tab 22 is opposite in polarity to the first tab 21, and along the first direction Z, one end of the second tab 22 close to the first tab 212 is a first end 2211. The solid-state electrolyte layer 23 is disposed between the first tab 21 and the second tab 22 along a second direction Y, and the second direction Y intersects the first direction Z. The insulating member 24 is at least partially disposed between the connecting portion 2121 and the first end 2211 along the first direction Z to insulate and separate the connecting portion 2121 and the second tab 22.

[0136] The electrode assembly 2 can be a laminated structure, i.e., the electrode assembly 2 is a laminated electrode assembly, the first tab 21, the solid-state electrolyte layer 23 and the second tab 22 are laminated to form a laminated structure, and the laminating direction of the first tab 21, the solid-state electrolyte layer 23 and the second tab 22 is parallel to the second direction Y. The electrode assembly 2 can also be a wound structure, i.e., the electrode assembly 2 is a wound electrode assembly, the first tab 21, the solid-state electrolyte layer 23 and the second tab 22 are wound to form a wound structure. In the wound electrode assembly, the electrode assembly 2 can include a flat area and a bent area, and the opposite ends of the flat area can be provided with the bent area. The laminating direction of the first tab 21, the solid-state electrolyte layer 23 and the second tab 22 located in the flat area is parallel to the second direction Y. In the embodiment shown in FIG. 6, the electrode assembly 2 is a laminated structure, and the first tab 21, the second tab 22 and the solid-state electrolyte layer 23 are all multiple.

[0137] One of the first tab 21 and the second tab 22 is a positive electrode tab, and the other is a negative electrode tab. It can be understood that the first tab 21 can be a positive electrode tab, and the second tab 22 can be a negative electrode tab; or the first tab 21 can be a negative electrode tab, and the second tab 22 can be a positive electrode tab. The first tab 21 can be one or multiple; and the second tab 22 can be one or multiple.

[0138] The second tab 22 can include a second body area 221 and a second tab 222, and the second tab 222 is arranged at one end of the second body area 221 along the first direction Z. The second body area 221 is arranged along the second direction Y with the first body area 211, and at least part of the solid-state electrolyte layer 23 is arranged between the first body area 211 and the second body area 221. Along the first direction Z, one end of the second body area 221 close to the first tab 212 is the first end 2211 of the second tab 222. Along the first direction Z, the first tab 212 and the second tab 222 can be located at the same end of the electrode assembly 2, or can be located at opposite ends of the electrode assembly 2, respectively. As an example, in the embodiments shown in FIGS. 7-10, along the first direction Z, the first tab 212 and the second tab 222 are located at the same end of the electrode assembly 2, and the end of the second body area 221 where the second tab 222 is arranged is the first end 2211. The first tab 212 and the second tab 222 are arranged spaced apart along the third direction X, and the first direction Z, the second direction Y and the third direction X are all intersected with each other, and any two of the first direction Z, the second direction Y and the third direction X can be arranged at an acute angle, a right angle or an obtuse angle.

[0139] As shown in FIG. 7, the first main body region 211 can include a first active material layer 2112 and a first current collector layer 2113, the first current collector layer 2113 is provided with the first active material layer 2112 on at least one surface in the thickness direction, the first tab 212 is connected to the first current collector layer 2113, and the first tab 212 and the first current collector layer 2113 can be integrally formed and jointly constitute a first current collector. The size of the first tab 212 along the third direction X can be smaller than the size of the first current collector layer 2113 along the third direction X. It can be understood that if the first tab 21 is a positive electrode tab, the first active material layer 2112 includes a positive electrode active material, and the first current collector is a positive electrode current collector; if the first tab 21 is a negative electrode tab, the first active material layer 2112 includes a negative electrode active material, and the first current collector is a negative electrode current collector.

[0140] As shown in FIG. 7, the second main body region 221 can include a second active material layer 2212 and a second current collector layer 2213, the second current collector layer 2213 is provided with the second active material layer 2212 on at least one surface in the thickness direction, the second tab 222 (shown in FIG. 10) is connected to the second current collector layer 2213, and the second tab 222 and the second current collector layer 2213 can be integrally formed and jointly constitute a second current collector. The size of the second tab 222 along the third direction X can be smaller than the size of the second current collector layer 2213 along the third direction X. Along the first direction Z, one end of the second current collector layer 2213 close to the second tab 222 can be located at the first end 2211, and one end of the second active material layer 2212 close to the second tab 222 can be located at the first end 2211 or can be farther away from the second tab 222 than the first end 2211. It can be understood that if the second tab 22 is a positive electrode tab, the second active material layer 2212 includes a positive electrode active material, and the second current collector is a positive electrode current collector; if the second tab 22 is a negative electrode tab, the second active material layer 2212 includes a negative electrode active material, and the second current collector is a negative electrode current collector.

[0141] The first tabs 212 in the electrode assembly 2 are multiple, and the folded portions 2122 of the multiple first tabs 212 are connected to form a folded area 25, which is used to be connected with other components, which can be a current collecting member or an electrode terminal 3, etc. In the embodiment in which the electrode assembly 2 is a laminated structure, the first tabs 21 can be multiple, and the folded portions 2122 of the first tabs 212 of the multiple first tabs 21 are connected, and it can be understood that the folded portions 2122 of the first tabs 212 of one first tab 21 are used to be connected with the folded portions 2122 of the first tabs 212 of the adjacent first tab 21. In the embodiment in which the electrode assembly 2 is a wound structure, the first tab 21 can be one, and the first tab 21 can be provided with multiple first tabs 212, and the multiple first tabs 212 of the first tab 21 are arranged at intervals along the winding direction of the first tab 21, and it can be understood that the folded portions 2122 of the first tabs 212 are used to be connected with the folded portions 2122 of the adjacent first tabs 212 in the same first tab 21.

[0142] The first tab 212 can be bent to form the folded portion 2122 and the connecting portion 2121. A part of the connecting portion 2121 is arranged opposite to the first end 2211 along the first direction Z, that is, the projection of the first connecting portion 21211 along the first direction Z covers at least a part of the first end 2211. At least a part of the insulating member 24 is arranged between the part of the connecting portion 2121 arranged opposite to the first end 2211 along the first direction Z and the first end 2211.

[0143] The insulating member 24 is of insulating material, and along the first direction Z, the insulating member 24 can be located entirely between the first end 2211 and the connecting portion 2121, or only a part thereof is located between the first end 2211 and the connecting portion 2121. The insulating member 24 can be connected to the first tab 21, for example, the insulating member 24 is connected to the first main body area 211 and / or the first tab 212; the insulating member 24 can also be connected to the second tab 22, for example, the insulating member 24 is connected to the first end 2211 of the second tab 22.

[0144] In the embodiment of the present application, the insulating member 24 is at least partially arranged between the connecting portion 2121 and the first end 2211 along the first direction Z, and the connecting portion 2121 of the first tab 212 can be insulated and separated from the second tab 22 by the insulating member 24, thereby reducing the risk of short circuit of the first tab 21 and the second tab 22 caused by the lap joint of the connecting portion 2121 and the first end 2211, and effectively improving the reliability of the battery monomer 10.

[0145] In some embodiments, referring to FIG. 11, which is a partial view of the electrode assembly 2 provided in some embodiments of the present application, the insulating member 24 includes a first insulating member 241, which is disposed on the connecting portion 2121 and at least partially located between the connecting portion 2121 and the first end 2211 in the first direction Z.

[0146] The first insulating member 241 is made of an insulating material. The first insulating member 241 can be a part of the insulating member 24, or the first insulating member 241 can be the insulating member 24. The first insulating member 241 can have a uniform thickness, or can have a non-uniform thickness, for example, a part of the first insulating member 241 can have a greater thickness than another part. The first insulating member 241 can be partially disposed between the connecting portion 2121 and the first end 2211, or can be entirely disposed between the connecting portion 2121 and the first end 2211 in the first direction Z.

[0147] The first insulating member 241 can be connected to the connecting portion 2121 to fix the first insulating member 241 to the connecting portion 2121. The first insulating member 241 can cover a part or all of the surface of the connecting portion 2121 facing the first end 2211 to separate the connecting portion 2121 and the first end 2211.

[0148] By disposing the first insulating member 241 on the connecting portion 2121 and locating at least a part of the first insulating member 241 between the connecting portion 2121 and the first end 2211, the risk of the surface of the connecting portion 2121 facing the first end 2211 contacting the first end 2211 can be reduced, and stable insulation between the connecting portion 2121 and the second pole piece 22 can be achieved. In addition, after the first pole piece 21 is formed, the first insulating member 241 can be disposed on the first tab 212, and then the first pole piece 21, the second pole piece 22, and the solid-state electrolyte layer 23 are formed into the electrode assembly 2, which can reduce the difficulty of arranging the first insulating member 241.

[0149] In some embodiments, still referring to FIG. 11, the connecting portion 2121 is bent to form a first connecting portion 21211 and a second connecting portion 21212 connected to each other, the first connecting portion 21211 is connected to the folding portion 2122 (shown in FIG. 8), the second connecting portion 21212 is connected to the first main body region 211, the first connecting portion 21211 is oppositely disposed to the first end 2211 in the first direction Z, the first connecting portion 21211 has a first surface 21211a facing the first end 2211, and at least a part of the first insulating member 241 is located between the first connecting portion 21211 and the first end 2211 and covers at least a part of the first surface 21211a.

[0150] The first connecting portion 21211, the second connecting portion 21212, and the folding portion 2122 can be three segments formed after the first tab 212 is bent. The first connecting portion 21211, the second connecting portion 21212, and the folding portion 2122 can all extend along a straight line trajectory. The first tab 212 can be bent at a position forming a circular arc segment, the first connecting portion 21211 and the second connecting portion 21212 can be connected by one circular arc segment, and the first connecting portion 21211 and the folding portion 2122 can be connected by another circular arc segment. The first connecting portion 21211 and the second connecting portion 21212 are arranged at an angle, and the first connecting portion 21211 and the second connecting portion 21212 can be arranged at an acute angle, a right angle, or an obtuse angle. The extension direction of the second connecting portion 21212 can be parallel to the first direction Z, or can be arranged at a non-zero angle with the first direction Z. The first connecting portion 21211 and the folding portion 2122 are arranged at an angle, and the first connecting portion 21211 and the folding portion 2122 can be arranged at an acute angle, a right angle, or an obtuse angle. The extension direction of the folding portion 2122 can be parallel to the first direction Z, or can be arranged at a non-zero angle with the first direction Z, for example, the extension direction of the folding portion 2122 is perpendicular to the first direction Z.

[0151] The first insulating member 241 can be arranged on the first connecting portion 21211, or a part of the first insulating member 241 can be arranged on the first connecting portion 21211, and the other part of the first insulating member 241 can be arranged on the folding portion 2122 and / or the second connecting portion 21212 and / or the first main body area 211. The first insulating member 241 can cover a part of the first surface 21211a, or can cover the entire first surface 21211a. As an example, the first surface 21211a is a plane.

[0152] The connecting portion 2121 is a bent structure, and after the connecting portion 2121 is bent, the first connecting portion 21211 of the connecting portion 2121 and the first end 2211 are in opposite states along the first direction Z. The first surface 21211a of the first connecting portion 21211 facing the first end 2211 is in contact with the first end 2211, which increases the risk of short circuit between the first tab 21 and the second tab 22. However, arranging at least part of the first insulating member 241 between the first connecting portion 21211 and the first end 2211 and covering at least part of the first surface 21211a can effectively reduce the risk of the first surface 21211a of the first connecting portion 21211 contacting the first end 2211, thereby reducing the risk of short circuit between the first tab 21 and the second tab 22.

[0153] In some embodiments, please continue to refer to FIG. 11, along the second direction Y, the second connecting portion 21212 has a second surface 21212a facing the second tab 22, the second surface 21212a is connected with the first surface 21211a, and the first insulating member 241 covers at least a portion of the second surface 21212a.

[0154] The first insulating member 241 can cover a portion of the second surface 21212a, or cover the entire first insulating member 241.

[0155] As an example, the second surface 21212a is a plane, and the first surface 21211a is connected with the second surface 21212a through a circular arc surface. The circular arc segment connecting the first connecting portion 21211 and the second connecting portion 21212 faces the surface of the second tab 22, which is the circular arc surface. The first insulating member 241 covers at least a portion of the circular arc surface. It can be understood that a portion of the first insulating member 241 is arranged on the first surface 21211a, another portion is arranged on the circular arc surface, and another portion is arranged on the second surface 21212a.

[0156] In the present embodiment, the first insulating member 241 covers the second surface 21212a of the second connecting portion 21212, so that the first insulating member 241 can play a role of separating the first connecting portion 21211 and the second tab 22, and also play a role of separating the second connecting portion 21212 and the second tab 22, thereby reducing the risk of contact between the second surface 21212a of the second connecting portion 21212 and the second tab 22, and causing short circuit between the first tab 21 and the second tab 22.

[0157] In some embodiments, please continue to refer to FIG. 11, along the first direction Z, the first main body area 211 has a second end 2111, the first tab 212 is connected to the second end 2111, and the solid-state electrolyte layer 23 includes a first overhanging area 231 beyond the second end 2111. Along the second direction Y, a portion of the first insulating member 241 is located between the first overhanging area 231 and the connecting portion 2121.

[0158] Along the first direction Z, one end of the first current collector layer 2113 close to the first tab 212 can be located at the second end 2111, and one end of the first active material layer 2112 close to the first tab 212 can be located at the second end 2111, or can be farther away from the first tab 212 than the second end 2111.

[0159] The first overhanging area 231 is a portion of the solid-state electrolyte layer 23 beyond the second end 2111 in the direction of the first main body area 211 pointing to the first tab 212. In a projection plane perpendicular to the second direction Y, the orthographic projection of the first overhanging area 231 partially overlaps with the orthographic projection of the connecting portion 2121.

[0160] In the embodiment shown in FIG. 11, along the second direction Y, the first overhanging region 231 is opposite to the second connecting portion 21212, a portion of the first insulating member 241 is located between the first overhanging region 231 and the second connecting portion 21212, the portion of the first insulating member 241 located between the first overhanging region 231 and the second connecting portion 21212 is spaced apart from the first overhanging region 231, and is connected to the second surface 21212a of the second connecting portion 21212. Along the first direction Z, the first insulating member 241 abuts against the second end 2111.

[0161] In the embodiment shown in FIG. 11, along the second direction Y, the first overhanging region 231 is opposite to the second connecting portion 21212, a portion of the first insulating member 241 is located between the first overhanging region 231 and the second connecting portion 21212, the portion of the first insulating member 241 located between the first overhanging region 231 and the second connecting portion 21212 is spaced apart from the first overhanging region 231, and is connected to the second surface 21212a of the second connecting portion 21212. Along the first direction Z, the first insulating member 241 abuts against the second end 2111.

[0162] In the embodiment shown in FIG. 11, along the second direction Y, the first overhanging region 231 is opposite to the second connecting portion 21212, a portion of the first insulating member 241 is located between the first overhanging region 231 and the second connecting portion 21212, the portion of the first insulating member 241 located between the first overhanging region 231 and the second connecting portion 21212 is spaced apart from the first overhanging region 231, and is connected to the second surface 21212a of the second connecting portion 21212. Along the first direction Z, the first insulating member 241 abuts against the second end 2111.

[0163] In some embodiments, please refer to FIG. 12, which is a partial view of an electrode assembly 2 provided in some embodiments of the present application. Along the second direction Y, the portion of the first insulating member 241 located between the first overhanging region 231 and the connecting portion 2121 abuts against the first overhanging region 231 and the connecting portion 2121.

[0164] It can be understood that the portion of the first insulating member 241 located between the first overhanging region 231 and the connecting portion 2121 maintains contact with the first overhanging region 231 and the connecting portion 2121.

[0165] In the process of forming the electrode assembly 2, it is generally necessary to apply pressure to the electrode assembly 2 so that the first tab 21 and the second tab 22 can be tightly attached to the solid electrolyte layer 23, for example, the electrode assembly 2 is subjected to isostatic pressing, in this process, the solid electrolyte layer 23 is easily cracked or sheared by the edge of the first tab 21 at the second end 2111. In the present embodiment, the first insulation member 241 located between the first overhanging area 231 and the connecting portion 2121 can support the first overhanging area 231 and the connecting portion 2121, so that the first overhanging area 231 and the connecting portion 2121 maintain a certain distance in the second direction Y, reducing the risk of the solid electrolyte layer 23 being cracked or sheared by the edge of the first main area 211 at the second end 2111 during the forming process of the electrode assembly 2.

[0166] In some embodiments, along the first direction Z, the first main area 211 has a second end 2111, and the first tab 212 is connected to the second end 2111. The first insulation member 241 includes a first insulation portion 2411 connected to the second end 2111 and extending along the extension direction of the first tab 212, and at least part of the first insulation portion 2411 is located between the connecting portion 2121 and the first end 2211 along the first direction Z.

[0167] The first insulation portion 2411 is the part of the first insulation member 241 extending from the second end 2111 along the extension direction of the first tab 21, and the extension direction of the first insulation portion 2411 is consistent with the extension direction of the first tab 212. The first insulation portion 2411 can be a part of the first insulation member 241, or the first insulation member 241 can only include the first insulation portion 2411, and the first insulation portion 2411 is the first insulation member 241.

[0168] As an example, the first insulation portion 2411 is a bent structure, and the first insulation portion 2411 is bent together with the connecting portion 2121. Part of the first insulation portion 2411 extends along the second connecting portion 21212, and another part extends along the first connecting portion 21211, and the part of the first insulation portion 2411 extending along the first connecting portion 21211 is located between the first connecting portion 21211 and the first end 2211 along the first direction Z.

[0169] In the present embodiment, the first insulation portion 2411 is connected to the second end 2111 and extends along the extension direction of the first tab 212, so that the size of the first insulation portion 2411 along the extension direction of the first tab 212 is longer, which increases the coverage range of the surface of the connecting portion 2121 covered by the first insulation portion 2411, and reduces the risk of the connecting portion 2121 being overlapped with the second tab 22.

[0170] In some embodiments, along the second direction Y, the first pole pieces 21 and the second pole pieces 22 are arranged alternately, and the second pole pieces 22 are one more than the first pole pieces 21 along the extension direction of the first lug 212. The length of the first insulation part 2411 is H, Q≤H≤2Q along the extension direction of the first lug 212. N is an even number, and Q=M1×N / 2+M2×(N-1) / 2+M3×(N-1); or N is an odd number, and Q=M1×(N-1) / 2+M2×(N-1) / 2+M3×(N-1). Wherein, the number of the first pole pieces 21 in the electrode assembly 2 is N; the thickness of the first pole piece 21 is M1, the thickness of the second pole piece 22 is M2, and the thickness of the solid-state electrolyte layer 23 is M3.

[0171] The thickness of the first pole piece 21 is the thickness of the first main body area 211, and the thickness of the second pole piece 22 is the thickness of the second main body area 221. It can be understood that the solid-state electrolyte layer 23 is arranged between adjacent first pole pieces 21 and second pole pieces 22.

[0172] If the first insulation part 2411 is bent into multiple segments, the length of each segment can be measured respectively, and the sum of the lengths of the multiple segments is the length of the first insulation part 2411 along the extension direction of the first lug 212. Of course, the length of the first insulation part 2411 in a straight state can also be measured after the first insulation part 2411 in a bent state is straightened, and this length is the length of the first insulation part 2411 along the extension direction of the first lug 212.

[0173] In the present embodiment, the length of the first insulation part 2411 is designed according to the number of the first pole pieces 21 and the thicknesses of the first pole pieces 21, the second pole pieces 22 and the solid-state electrolyte layer 23, so that the first insulation part 2411 has sufficient length, and part of the first insulation part 2411 can extend between the connecting part 2121 and the first end 2211 to effectively separate the connecting part 2121 and the second pole piece 22 in the first direction Z.

[0174] In some embodiments, the solid-state electrolyte layer 23 includes a first overhanging area 231 beyond the second end 2111. Along the second direction Y, part of the first insulation part 2411 is located between the first overhanging area 231 and the connecting part 2121, and abuts against the first overhanging area 231 and the connecting part 2121.

[0175] The first insulation part 2411 can be an equal-thickness structure or a non-equal-thickness structure.

[0176] As an example, in the embodiment shown in FIG. 12, along the second direction Y, a portion of the first insulating part 2411 is located between the first overhanging region 231 and the second connecting part 21212. The portion of the first insulating part 2411 located between the first overhanging region 231 and the second connecting part 21212 abuts against the first overhanging region 231 and the second connecting part 21212, and abuts against the second end 2111.

[0177] In the present embodiment, the first insulating part 2411 is connected to the second end 2111 and a portion thereof is located between the first overhanging region 231 and the connecting part 2121, so that the first insulating part 2411 can stably support the first overhanging region 231 and the connecting part 2121, so that the first overhanging region 231 and the connecting part 2121 are kept at a distance in the second direction Y, reducing the risk of the solid-state electrolyte layer 23 being cracked or sheared by the edge of the first main region 211 at the second end 2111 during the forming of the electrode assembly 2.

[0178] In some embodiments, please refer to FIG. 12 and FIG. 13, which is a structural schematic diagram of the first insulating part 241 shown in FIG. 12. The first insulating part 2411 includes a first portion 24111 and a second portion 24112. The first portion 24111 is arranged at the connecting part 2121, and along the first direction Z, at least a portion of the first portion 24111 is located between the connecting part 2121 and the first end 2211. The second portion 24112 is connected to the first portion 24111, and the second portion 24112 is connected to the second end 2111. The thickness of the second portion 24112 is greater than the thickness of the first portion 24111, and along the second direction Y, at least a portion of the second portion 24112 is located between the first overhanging region 231 and the connecting part 2121, and abuts against the first overhanging region 231 and the connecting part 2121.

[0179] The first portion 24111 and the second portion 24112 can be integrally formed. Along the first direction Z, the first portion 24111 can be partially located between the connecting part 2121 and the first end 2211, or can be entirely located between the connecting part 2121 and the first end 2211. Along the second direction Y, the second portion 24112 can be partially located between the first overhanging region 231 and the connecting part 2121, or can be entirely located between the first overhanging region 231 and the connecting part 2121.

[0180] The thickness of the first portion 24111 is L1, and the thickness of the second portion 24112 is L2, L1

[0181] As an example, in the embodiment shown in FIG. 12, along the second direction Y, the second portion 24112 is located between the first overhang region 231 and the second connecting portion 21212. Along the first direction Z, a portion of the first portion 24111 is located between the first connecting portion 21211 and the first end 2211. A portion of the first portion 24111 extends along the second connecting portion 21212 and is connected to the second surface 21212a, and another portion of the first portion 24111 extends along the first connecting portion 21211 and is connected to the first surface 21211a.

[0182] In the present embodiment, the second portion 24112 with a larger thickness is arranged between the first overhang region 231 and the connecting portion 2121, and the second portion 24112 can provide good support to the first overhang region 231 and the connecting portion 2121 in the second direction Y. The first portion 24111 with a smaller thickness is arranged in the connecting portion 2121, and the first portion 24111 has better bending performance to adapt to the bending of the connecting portion 2121. The first insulating portion 2411 with such a structure can not only provide good support to the first overhang region 231 and the connecting portion 2121, but also can bend together with the connecting portion 2121, and can reduce the material usage of the first insulating portion 2411, having better economy.

[0183] In some embodiments, along the first direction Z, the size of the second portion 24112 is d, and the size of the first overhang region 231 is D, 0.1≤d / D≤1.

[0184] d / D can take any one of 0.1, 0.2, 0.3, 0.4, 0.5, 0.6, 0.7, 0.8, 0.9, 1, etc. as a point value or a range value between any two of them.

[0185] In the present embodiment, d / D≥0.1, so that the ratio of the size of the second portion 24112 along the first direction Z to the size of the first overhang region 231 along the first direction Z is not too small, so that the second portion 24112 can provide sufficient support to the first overhang region 231 and the connecting portion 2121, reducing the risk of the solid-state electrolyte layer 23 being cracked or sheared during the forming of the electrode assembly 2. d / D≤1, so that the ratio of the size of the second portion 24112 along the first direction Z to the size of the first overhang region 231 along the first direction Z is not too large, which can reduce the material usage of the second portion 24112, having better economy. Therefore, 0.1≤d / D≤1, taking into account the support performance and economy of the second portion 24112.

[0186] In some embodiments, 2mm≤d≤10mm.

[0187] d can take any one of 2mm, 3mm, 4mm, 5mm, 6mm, 7mm, 8mm, 9mm, 10mm, etc. or a range value between any two of them.

[0188] In the embodiment, d≥2mm, so that the size of the second portion 24112 along the first direction Z is large, which reduces the difficulty of forming the second portion 24112 and enables the second portion 24112 to provide sufficient support for the first overhang region 231 and the connecting portion 2121. d≤10mm, so that the size of the second portion 24112 along the first direction Z is not too large, which reduces material waste.

[0189] In some embodiments, referring to FIG. 14 and FIG. 15, FIG. 14 is a partial view of an electrode assembly 2 provided in some other embodiments of the application; and FIG. 15 is a structural schematic view of a first insulating member 241 shown in FIG. 14. The first insulating member 241 further includes a second insulating portion 2412, the second insulating portion 2412 is connected with the second portion 24112, the thickness of the second insulating portion 2412 is less than the thickness of the second portion 24112, and the second insulating portion 2412 is arranged in a stack with the first main body region 211 along the second direction Y.

[0190] The second insulating portion 2412 and the first insulating portion 2411 can be integrally formed. The thickness of the second insulating portion 2412 is b, and b

[0191] In the embodiment, the second insulating portion 2412 of the first insulating member 241 is arranged in a stack with the first main body region 211 along the second direction Y, which on one hand increases the total length of the first insulating member 241, and further reduces the risk of the connecting portion 2121 overlapping with the second tab 22; and on the other hand increases the contact area between the first insulating member 241 and the first tab 21, so that the first insulating member 241 is more stable on the first tab 21, to realize stable insulation between the connecting portion 2121 and the second tab 22. In addition, since the thickness of the second insulating portion 2412 is less than the thickness of the second portion 24112, the thickness of the second insulating portion 2412 is not too large, which reduces the space occupied by the second insulating portion 2412 along the second direction Y.

[0192] In some embodiments, still referring to FIG. 14 and FIG. 15, the first insulating member 241 further includes a second insulating portion 2412, the second insulating portion 2412 is connected with the first insulating portion 2411, and the second insulating portion 2412 is arranged in a stack with the first main body region 211 along the second direction Y.

[0193] Along the second direction Y, the second insulating part 2412 can be laminated with the region of the first body area 211 where the first current collector layer 2113 is not covered by the first active material layer 2112, or the second insulating part 2412 can be laminated with the first active material layer 2112 of the first body area 211.

[0194] As an example, in a projection plane perpendicular to the second direction Y, the orthographic projection of the second insulating part 2412 overlaps the orthographic projection of a part of the first body area 211.

[0195] In the present embodiment, the second insulating part 2412 of the first insulating member 241 is laminated with the first body area 211 along the second direction Y, which on one hand increases the total length of the first insulating member 241, and further reduces the risk of the connecting part 2121 overlapping the second tab 22; on the other hand, the contact area between the first insulating member 241 and the first tab 21 is increased, so that the first insulating member 241 is more firmly fixed on the first tab 21, to realize stable insulation between the connecting part 2121 and the second tab 22.

[0196] In some embodiments, please refer to FIG. 16, which is a schematic view of the connection between the first insulating member 241 and the first tab 21 shown in FIG. 14. The first body area 211 includes the first current collector layer 2113 and the first active material layer 2112, the first current collector layer 2113 is connected with the first tab 212, and the first active material layer 2112 is located at the second end 2111 along the first direction Z close to one end of the first tab 212. Along the second direction Y, the side of the first current collector layer 2113 facing the solid-state electrolyte layer 23 (shown in FIG. 14) is provided with the first active material layer 2112, and the second insulating part 2412 is laminated with the first active material layer 2112.

[0197] The first current collector layer 2113 and the first tab 212 can be integrally formed to jointly constitute the first current collector. The first active material layer 2112 can be an equal-thickness structure or a non-equal-thickness structure.

[0198] It can be understood that along the second direction Y, if the two sides of the first tab 21 are both provided with the solid-state electrolyte layer 23, then the two opposite sides of the first current collector layer 2113 are both provided with the first active material layer 2112.

[0199] As an example, along the second direction Y, the two sides of the first tab 21 are both provided with the second tab 22 (shown in FIG. 14), the two sides of the first current collector layer 2113 are both provided with the first active material layer 2112, and the second insulating part 2412 is located between the solid-state electrolyte layer 23 and the first active material layer 2112. In a projection plane perpendicular to the second direction Y, the orthographic projection of the second insulating part 2412 overlaps the orthographic projection of a part of the first active material layer 2112.

[0200] In this embodiment, the second insulating part 2412 is stacked with the first active material layer 2112, so that the first insulating part 241 plays a certain protective role for the edge area of the first active material layer 2112 close to the second end 2111, reduces the risk of the edge area of the first active material layer 2112 separating from the first current collector layer 2113, and can reduce the risk of the edge area of the first active material layer 2112 contacting the second tab 22.

[0201] In some embodiments, still referring to FIG. 16, the first active material layer 2112 includes a main body part 21121 and a thinned part 21122. The thinned part 21122 is arranged at one end of the main body part 21121 close to the first tab 212 along the first direction Z, and the thickness of the thinned part 21122 is less than the thickness of the main body part 21121. Along the second direction Y, the second insulating part 2412 is stacked with the thinned part 21122.

[0202] It can be understood that the first active material layer 2112 is a non-equal-thickness structure.

[0203] The main body part 21121 can be an equal-thickness structure or a non-equal-thickness structure. The thinned part 21122 can be an equal-thickness structure or a non-equal-thickness structure. For example, the thickness of the thinned part 21122 gradually decreases along the direction of the main body part 21121 pointing to the thinned part 21122. In this case, the maximum thickness of the thinned part 21122 can be less than or equal to the minimum thickness of the main body part 21121, so as to achieve the thickness of the thinned part 21122 being less than the thickness of the main body part 21121.

[0204] As an example, the main body part 21121 is an equal-thickness structure, and the thinned part 21122 is also an equal-thickness structure. The second insulating part 2412 is located between the solid-state electrolyte layer 23 (shown in FIG. 14) and the thinned part 21122. In the projection plane perpendicular to the second direction Y, the orthographic projection of the second insulating part 2412 overlaps with the orthographic projection of a part of the thinned part 21122.

[0205] In this embodiment, along the second direction Y, the second insulating part 2412 is stacked with the thinned part 21122, which makes full use of the gap between the thinned part 21122 and the solid-state electrolyte layer 23, and is conducive to the main body part 21121 of the first active material layer 2112 closely adhering to the solid-state electrolyte layer 23, thereby reducing the interface impedance of the first tab 21 and the solid-state electrolyte layer 23.

[0206] In some embodiments, referring to FIG. 17 and FIG. 18, FIG. 17 is a partial view of the electrode assembly 2 according to some embodiments of the present application, and FIG. 18 is a schematic view of the connection between the first insulating member 241 and the first tab 21. The first main body region 211 includes the first current collector 2113, the first active material layer 2112, and the insulating layer 2114. The first current collector 2113 is connected to the first tab 212. The insulating layer 2114 is arranged at one end of the first active material layer 2112 close to the first tab 212 along the first direction Z, and the one end of the insulating layer 2114 close to the first tab 212 along the first direction Z is located at the second end 2111. Along the second direction Y, the side of the first current collector 2113 facing the solid-state electrolyte layer 23 is provided with the first active material layer 2112 and the insulating layer 2114, and the second insulating portion 2412 is arranged in a stack with the insulating layer 2114.

[0207] The first current collector and the first tab 212 can be integrally formed to jointly constitute the first current collector. The first active material layer 2112 can have an equal thickness structure or a non-equal thickness structure. The insulating layer 2114 is made of an insulating material, and the thickness of the insulating layer 2114 can be equal to or different from the thickness of the first active material layer 2112. Along the first direction Z, the size of the insulating layer 2114 can be greater than, less than, or equal to the size of the second insulating portion 2412. In a projection plane perpendicular to the second direction Y, the projection of the second insulating portion 2412 and the projection of the first active material layer 2112 can partially overlap or not overlap.

[0208] It can be understood that along the second direction Y, if the first tab 21 is provided with the solid-state electrolyte layer 23 on both sides, the first current collector 2113 is provided with the first active material layer 2112 and the insulating layer 2114 on both opposite sides.

[0209] As an example, along the second direction Y, the first tab 21 is provided with the second tab 22 on both sides, and the first current collector 2113 is provided with the first active material layer 2112 and the insulating layer 2114 on both sides. Along the first direction Z, the solid-state electrolyte layer 23 and the second tab 22 both extend beyond the one end of the first active material layer 2112 close to the insulating layer 2114, and the second end 2111 is farther away from the one end of the first active material layer 2112 close to the insulating layer 2114 than the first end 2211. Along the second direction Y, the second insulating portion 2412 is located between the insulating layer 2114 and the solid-state electrolyte layer 23. In a projection plane perpendicular to the second direction Y, the projection of the second insulating portion 2412 and the projection of the first active material layer 2112 do not overlap, so that the second insulating portion 2412 does not block the first active material layer 2112, reducing the risk of the second insulating portion 2412 blocking the transmission of metal ions between the first tab 21 and the second tab 22.

[0210] In the embodiment, the insulation layer 2114 is arranged to reduce the risk that the burr of the edge region of the first current collector layer 2113 penetrates through the solid-state electrolyte layer 23 and contacts the second tab 22. The second insulation portion 2412 is arranged in a stack with the insulation layer 2114, and the second insulation portion 2412 can separate the first current collector layer 2113 and the second tab 22 together with the insulation layer 2114, further reducing the risk that the burr of the edge region of the first current collector layer 2113 penetrates through the solid-state electrolyte layer 23 and contacts the second tab 22.

[0211] In some embodiments, referring to FIGS. 16 and 18, along the first direction Z, the size of the second insulation portion 2412 is a, and the size of the first main body region 211 is A, 0.01≤a / A≤0.05.

[0212] a / A can take any one of the point values 0.01, 0.015, 0.02, 0.025, 0.03, 0.035, 0.04, 0.045, 0.05, or a range value between any two of them.

[0213] In the embodiment, a / A≥0.01, so that the ratio of the size of the second insulation portion 2412 along the first direction Z to the size of the first main body region 211 along the first direction Z is not too small, so that the second insulation portion 2412 of the first insulation member 241 clamped by the first main body region 211 and the solid-state electrolyte layer 23 has sufficient length, so that the first insulation member 241 is more secure on the first tab 21. a / A≤0.05, so that the ratio of the size of the second insulation portion 2412 along the first direction Z to the size of the first main body region 211 along the first direction Z is not too large, on the one hand, the use of the second insulation portion 2412 can be reduced, and better economy is achieved; on the other hand, the risk that the active material layer (the first active material layer 2112) in the first main body region 211 is blocked by the second insulation portion 2412 in a large area can be reduced.

[0214] In some embodiments, 0.05mm≤a≤5mm.

[0215] a can take any one of the point values 0.05mm, 0.1mm, 0.2mm, 0.5mm, 0.8mm, 1mm, 1.5mm, 2mm, 2.5mm, 3mm, 3.5mm, 4mm, 4.5mm, 5mm, or a range value between any two of them.

[0216] In the embodiment, a≥0.05mm, so that the second insulation portion 2412 has sufficient length to facilitate the arrangement of the second insulation portion 2412 on the surface of the first main body region 211. a≤5mm, so that the second insulation portion 2412 is not too long, reducing the use of the second insulation portion 2412, and better economy is achieved.

[0217] In some embodiments, the size of the second insulating portion 2412 along the second direction Y is b, and the size of the first main body region 211 along the second direction Y is B, 0.05≤b / B≤0.25.

[0218] The size of the second insulating portion 2412 along the second direction Y is the thickness of the second insulating portion 2412. The size of the first main body region 211 along the second direction Y is the thickness of the first main body region 211, B=M1.

[0219] b / B can take any one of 0.05, 0.07, 0.1, 0.12, 0.15, 0.17, 0.18, 0.2, 0.22, 0.25, etc., or a range value between any two of them.

[0220] In the present embodiment, b / B≥0.05, so that the ratio of the size of the second insulating portion 2412 along the second direction Y to the size of the first main body region 211 along the second direction Y is not too small, so that the second insulating portion 2412 has sufficient strength. b / B≤0.25, so that the ratio of the size of the second insulating portion 2412 along the second direction Y to the size of the first main body region 211 along the second direction Y is not too large, reducing the thickness ratio of the second insulating portion 2412 in the first main body region 211, leaving more space for the active material layer (the first active material layer 2112) in the first main body region 211, which is conducive to improving the volumetric energy density of the battery monomer 10.

[0221] In some embodiments, 0.01mm≤b≤0.1mm.

[0222] b can take any one of 0.01mm, 0.02mm, 0.03mm, 0.04mm, 0.05mm, 0.06mm, 0.07mm, 0.08mm, 0.09mm, 0.1mm, etc., or a range value between any two of them.

[0223] b≥0.01mm, so that the second insulating portion 2412 has sufficient thickness and improves the strength of the second insulating portion 2412. b≤0.1mm, so that the second insulating portion 2412 is not too thick, reducing the material of the second insulating portion 2412 and having better economy.

[0224] In some embodiments, referring to FIG. 19, which is a partial view of a top region of the electrode assembly 2 shown in FIG. 6. The electrode assembly 2 includes a plurality of first tabs 21 arranged along the second direction Y, and a second tab 22 is arranged between two adjacent first tabs 21. The plurality of first tabs 21 includes two third tabs 26, and the second tab 22 between the two third tabs 26 is arranged opposite to the convergence region 25 along the first direction Z. The projection of the first insulating member 241 arranged on the two third tabs 26 along the first direction Z collectively covers the first end 2211 of the second tab 22 between the two third tabs 26.

[0225] The convergence portions 2122 of the plurality of first tabs 21 can be stacked together to form the convergence region 25. The convergence portions 2122 of the plurality of first tabs 21 can be connected by welding or bonding, etc. The convergence region 25 is used to connect with other components, which can be a current collecting member or an electrode terminal 3, etc. Along the second direction Y, the convergence region 25 can be located at the middle position of the electrode assembly 2, or can be offset from the middle position of the electrode assembly 2, so that the convergence region 25 is close to one surface of the electrode assembly 2 along the second direction Y, and is away from the other surface of the electrode assembly 2 along the second direction Y.

[0226] Among the plurality of first tabs 21, two first tabs 21 are third tabs 26, and the two third tabs 26 are arranged adjacent to each other, i.e. no other first tab 21 is arranged between the two third tabs 26. A second tab 22 is arranged between the two third tabs 26, and the second tab 22 is arranged opposite to the convergence region 25 along the first direction Z. It can be understood that the first tabs 21 located on both sides of the second tab 22 arranged opposite to the convergence region 25 along the first direction Z and closest to the second tab 22 are third tabs 26.

[0227] The first insulating member 241 arranged on the two third tabs 26 collectively separates the first end 2211 of the second tab 22 between the two third tabs 26 and the connection portion 2121 of the first tab 212 of the two third tabs 26.

[0228] As an example, in the embodiment shown in FIG. 19, the electrode assembly 2 is a lamination structure. The number of second tabs 22 is one more than the number of first tabs 21, and one first tab 21 is arranged between two adjacent second tabs 22. Along the second direction Y, the convergence region 25 is located at the middle position of the electrode assembly 2. One second tab 22 located at the middle position is arranged opposite to the convergence region 25 along the first direction Z.

[0229] In the embodiment, the projections of the first insulating members 241 provided on the two third pole pieces 26 along the first direction Z jointly cover the first end 2211 of the second pole piece 22 located between the two third pole pieces 26, thereby reducing the risk of the connecting portions 2121 of the first lugs 212 of the two third pole pieces 26 being overlapped with the first end 2211 of the second pole piece 22 located between the two third pole pieces 26.

[0230] In some embodiments, please continue to refer to FIG. 19, the plurality of first pole pieces 21 further comprises a fourth pole piece 27, the fourth pole piece 27 is arranged along the second direction Y with the third pole piece 26. The projection of the first insulating member 241 provided on the fourth pole piece 27 along the first direction Z covers the first end 2211 of the second pole piece 22 adjacent to the fourth pole piece 27 and located on the side of the fourth pole piece 27 close to the folding area 25.

[0231] In all the first pole pieces 21, one first pole piece 21 can be the fourth pole piece 27, that is, the fourth pole piece 27 is one, or a plurality of first pole pieces 21 can be the fourth pole piece 27, that is, the fourth pole piece 27 is a plurality. All the first pole pieces 21 except the third pole piece 26 can be the fourth pole piece 27.

[0232] As shown in FIG. 19, the second direction Y is parallel to the left-right direction. For the fourth pole piece 27 located on the left side of the third pole piece 26, the projection of the first insulating member 241 provided on the fourth pole piece 27 along the first direction Z covers the first end 2211 of the second pole piece 22 on the right side of the fourth pole piece 27 and closest to the fourth pole piece 27. For the fourth pole piece 27 located on the right side of the third pole piece 26, the projection of the first insulating member 241 provided on the fourth pole piece 27 along the first direction Z covers the first end 2211 of the second pole piece 22 on the left side of the fourth pole piece 27 and closest to the fourth pole piece 27.

[0233] Since the fourth pole piece 27 is arranged along the second direction Y with the third pole piece 26, at least part of the connecting portion 2121 of the first lug 212 of the fourth pole piece 27 will extend obliquely towards the third pole piece 26, and the connecting portion 2121 of the first lug 212 of the fourth pole piece 27 is more likely to be overlapped with the first end 2211 of the second pole piece 22 adjacent to the fourth pole piece 27 and located on the side of the fourth pole piece 27 close to the folding area 25. Since the projection of the first insulating member 241 provided on the fourth pole piece 27 along the first direction Z covers the first end 2211 of the second pole piece 22 adjacent to the fourth pole piece 27 and located on the side of the fourth pole piece 27 close to the folding area 25, the risk of the connecting portion 2121 of the first lug 212 of the fourth pole piece 27 being overlapped with the first end 2211 of the second pole piece 22 adjacent to the fourth pole piece 27 and located on the side of the fourth pole piece 27 close to the folding area 25 is effectively reduced.

[0234] In some embodiments, please continue to refer to FIG. 19, along the second direction Y, the two opposite surfaces of the second tab 22 are respectively provided with two solid-state electrolyte layers 23. In the projection plane perpendicular to the first direction Z, the orthographic projection of the two solid-state electrolyte layers 23 respectively provided on the two opposite surfaces of the second tab 22 partially overlaps with the orthographic projection of the first insulating member 241 provided on the fourth tab 27.

[0235] Along the second direction Y, the two opposite surfaces of the second tab 22 are respectively provided with two solid-state electrolyte layers 23, that is, the two opposite surfaces of the second tab 22 are both provided with solid-state electrolyte layers 23.

[0236] The projection of the first insulating member 241 provided on the fourth tab 27 along the first direction Z covers not only the first end 2211 of the second tab 22 adjacent to the fourth tab 27 and located on the side of the fourth tab 27 close to the folding area 25, but also the two solid-state electrolyte layers 23 respectively located on the two opposite surfaces of the second tab 22.

[0237] For example, in the projection plane perpendicular to the first direction Z, the size of the orthographic projection of the first insulating member 241 provided on the fourth tab 27 along the second direction Y is greater than the sum of the size of the orthographic projection of the second tab 22 along the second direction Y and the size of the orthographic projection of the two solid-state electrolyte layers 23 along the second direction Y.

[0238] In the embodiment, in the projection plane perpendicular to the first direction Z, the orthographic projection of the two solid-state electrolyte layers 23 partially overlaps with the orthographic projection of the first insulating member 241 provided on the fourth tab 27, so that the projection of the first insulating member 241 provided on the fourth tab 27 along the first direction Z can cover not only the second tab 22 but also the solid-state electrolyte layers 23 on both sides of the second tab 22, thereby reducing the risk of the connecting part 2121 of the first tab 212 of the fourth tab 27 overlapping with the adjacent second tab 22.

[0239] In some embodiments, please refer to FIG. 20, which is a schematic diagram of the connection between the first tab 21 and the first insulating member 241 according to some embodiments of the present application. Along the third direction X, the first insulating member 241 exceeds at least one edge of the first tab 212, and the first direction Z, the second direction Y and the third direction X are not coplanar and intersect with each other.

[0240] Along the third direction X, the first tab 212 has two opposite edges, which are the first edge 2123 and the second edge 2124 respectively, and the first insulating member 241 can exceed the first edge 2123 and / or the second edge 2124. The first edge 2123 and the second edge 2124 can be arranged in parallel, or can be arranged at an acute angle or an obtuse angle. In the embodiment shown in FIG. 20, the first edge 2123 and the second edge 2124 are arranged at an acute angle.

[0241] As an example, the first direction Z, the second direction Y and the third direction X are perpendicular to each other two by two.

[0242] In the embodiment, along the third direction X, the first insulating member 241 exceeds at least one edge of the first tab 212, the size of the first insulating member 241 in the third direction X is increased, and the risk of the connection part 2121 being overlapped with the second tab 22 is reduced.

[0243] In some embodiments, please continue to refer to FIG. 20, along the third direction X, the first insulating member 241 exceeds two opposite edges of the first tab 212.

[0244] Along the third direction X, the first insulating member 241 has two exceeding parts, one of which is the part of the first insulating member 241 exceeding the first edge 2123 of the first tab 212, and the other of which is the part of the first insulating member 241 exceeding the second edge 2124 of the first tab 212.

[0245] In the embodiment, along the third direction X, the first insulating member 241 exceeds two opposite edges of the first tab 212, the size of the first insulating member 241 in the third direction X is further increased, the first insulating member 241 can cover more areas of the surface of the connection part 2121 along the third direction X, and the risk of the connection part 2121 being overlapped with the second tab 22 is reduced.

[0246] In some embodiments, please continue to refer to FIG. 20, along the third direction X, the size of the first insulating member 241 is greater than the size of the first tab 212.

[0247] Along the third direction X, the size of the first tab 212 is D1, D1 is the maximum distance between the first edge 2123 and the second edge 2124 along the third direction X; along the third direction X, the size of the first insulating member 241 is D2, D2 is the maximum distance between the two opposite ends of the first insulating member 241 along the third direction X, and D2>D1.

[0248] In the embodiment, D2>D1, so that the first insulating member 241 has a certain redundancy in the third direction X, which is beneficial to the first insulating member 241 covering more areas of the surface of the connection part 2121 after being arranged on the connection part 2121.

[0249] In some embodiments, please refer to FIG. 21, which is a partial view of an electrode assembly 2 provided by other embodiments of the application. The insulating member 24 includes a second insulating member 242, and the first insulating member 241 and the second insulating member 242 are arranged on two sides of the first tab 212 in the thickness direction respectively.

[0250] The material of the second insulating member 242 and the first insulating member 241 can be the same or different. The second insulating member 242 can be an insulating tape or an insulating coating provided on the first tab 21.

[0251] The second insulating member 242 can be provided on the entire first tab 212, for example, the entire second insulating member 242 is provided on the first connecting portion 21211, or for example, part of the second insulating member 242 is provided on the first connecting portion 21211, and another part of the second insulating member 242 is provided on the second connecting portion 21212. The second insulating member 242 can be provided on part of the first tab 212, and another part of the second insulating member 242 is provided on the first main body portion 211 and stacked with the first main body portion 211. For example, as shown in FIG. 21, part of the second insulating member 242 is stacked with the thinned portion 21122 of the first active material layer 2112.

[0252] In this embodiment, the second insulating member 242 is provided so that more surfaces of the first tab 212 are covered, further reducing the risk of the first tab 212 being overlapped with the second tab 22.

[0253] In addition, taking the first insulating member 241 and the second insulating member 242 as insulating tapes for example, after the first tab 21 is formed, two insulating tapes can be respectively provided on both sides of the first tab 212 in the thickness direction to correspond to cover both surfaces of the first tab 212 in the thickness direction. After the first tab 21, the second tab 22 and the solid electrolyte layer 23 are formed into the electrode assembly 2, if the first tab 212 is bent in one direction, one of the insulating tapes can separate the first tab 212 and the second tab 22, and if the first tab 212 is bent in the opposite direction, the other insulating tape can separate the first tab 212 and the second tab 22.

[0254] In some embodiments, along the third direction X, the first insulating member 241 and the second insulating member 242 both extend beyond at least one edge of the first tab 212, and the first direction Z, the second direction Y and the third direction X are not coplanar and intersect with each other. Among them, the portions of the first insulating member 241 and the second insulating member 242 extending beyond the same edge of the first tab 212 along the third direction X are connected to each other.

[0255] The portions of the first insulating member 241 and the second insulating member 242 extending beyond the same edge of the first tab 212 along the third direction X can be bonded, heat-welded, etc.

[0256] As an example, along the third direction X, the first insulating piece 241 and the second insulating piece 242 both extend beyond two edges opposite to each other of the first tab 212, which are respectively the first edge 2123 (shown in FIG. 20) and the second edge 2124 (shown in FIG. 20). The portions of the first insulating piece 241 and the second insulating piece 242 extending beyond the first edge 2123 along the third direction X are connected to each other, and the portions of the first insulating piece 241 and the second insulating piece 242 extending beyond the second edge 2124 along the third direction X are connected to each other.

[0257] The portions of the first insulating piece 241 and the second insulating piece 242 extending beyond the same edge of the first tab 212 along the third direction X are connected to each other, which enhances the firmness of the first insulating piece 241 arranged on the first tab 212 and reduces the risk of the first insulating piece 241 being separated from the first tab 212. In addition, the first insulating piece 241 and the second insulating piece 242 as a whole are in a state of wrapping the first tab 212, which can further reduce the risk of the connecting portion 2121 of the first tab 212 being overlapped with the second tab 22.

[0258] In some embodiments, the first insulating piece 241 is an insulating tape arranged on the first tab 21.

[0259] The insulating tape is attached to the surface of the first tab 21, for example, a portion of the insulating tape is attached to the surface of the connecting portion 2121 of the first tab 212, and another portion is attached to the surface of the first main body region 211.

[0260] As an example, the material of the first insulating piece 241 can include PP (Polypropylene), PET (Polyethylene Terephthalate), etc.

[0261] In the present embodiment, the first insulating piece 241 is an insulating tape arranged on the first tab 21, and the first insulating piece 241 with such a structure has low manufacturing cost and low difficulty in connection with the first tab 21.

[0262] In some embodiments, the first insulating piece 241 is an insulating coating arranged on the first tab 21.

[0263] As an example, the insulating coating can be an inorganic non-metallic coating such as aluminum oxide, calcium oxide, etc.

[0264] In the present embodiment, the first insulating piece 241 is an insulating coating arranged on the first tab 21, and the first insulating piece 241 with such a structure has high connection strength with the first tab 21 and is not easy to be separated from the first tab 21.

[0265] In some embodiments, referring to FIG. 22 and FIG. 23, FIG. 22 is a structural schematic diagram of the electrode assembly 2 according to some embodiments of the present application; and FIG. 23 is an enlarged view of part C in FIG. 22. The insulating member 24 comprises a third insulating member 243, which is arranged on the second tab 22 and at least partially arranged between the connecting portion 2121 and the first end 2211 along the first direction Z.

[0266] The third insulating member 243 is made of insulating material. The third insulating member 243 can be a part of the insulating member 24, or the third insulating member 243 can be the insulating member 24. In the embodiments in which the insulating member 24 further comprises the first insulating member 241, the first insulating member 241 and the third insulating member 243 are both parts of the insulating member 24, and the first insulating member 241 and the third insulating member 243 can be arranged independently and separately, or can be connected to each other.

[0267] In the embodiments in which the electrode assembly 2 comprises a plurality of second tabs 22 and the plurality of second tabs 22 are arranged along the second direction Y, the plurality of second tabs 22 can share one third insulating member 243, or each second tab 22 can be provided with one third insulating member 243. As an example, in the embodiments shown in FIG. 22 and FIG. 23, each second tab 22 is provided with one third insulating member 243.

[0268] Along the first direction Z, the third insulating member 243 can be partially arranged between the connecting portion 2121 and the first end 2211, or can be completely arranged between the connecting portion 2121 and the first end 2211.

[0269] The third insulating member 243 can be connected to the second tab 22, such as being bonded to the second tab 22. The third insulating member 243 can also only be in contact with the second tab 22, such as being placed on the first end 2211.

[0270] The third insulating member 243 can cover part of the first end 2211, or can cover the entire first end 2211.

[0271] In the present embodiments, by arranging the third insulating member 243 on the second tab 22 and at least partially arranging the third insulating member 243 between the connecting portion 2121 and the first end 2211, the risk of the connecting portion 2121 being overlapped with the second tab 22 can be reduced, and stable insulation between the connecting portion 2121 and the second tab 22 can be achieved. In addition, the third insulating member 243 is less likely to affect the bending of the first tab 212.

[0272] In some embodiments, the third insulating member 243 completely covers the first end 2211.

[0273] The second pole piece 22 has a first end face at the end of the first end 2211, and the third insulating member 243 completely covers the first end 2211, i.e., the third insulating member 243 covers the entire first end face.

[0274] In this embodiment, the third insulating member 243 completely covers the first end 2211, thereby increasing the area of the third insulating member 243 covering the first end 2211 and reducing the risk of the connection portion 2121 being overlapped with the second pole piece 22.

[0275] In some embodiments, please continue to refer to FIGS. 22 and 23, along the second direction Y, the two opposite surfaces of the second pole piece 22 are respectively provided with two solid-state electrolyte layers 23. In the projection plane perpendicular to the first direction Z, the orthographic projection of the two solid-state electrolyte layers 23 respectively arranged on the two opposite surfaces of the second pole piece 22 partially overlaps with the orthographic projection of the third insulating member 243.

[0276] For example, along the first direction Z, the solid-state electrolyte layer 23 has a second end face facing the connection portion 2121, the second end face is flush with the first end face, and the third insulating member 243 covers part or all of the second end face of the solid-state electrolyte layer 23.

[0277] In this embodiment, in the projection plane perpendicular to the first direction Z, the orthographic projection of the two solid-state electrolyte layers 23 partially overlaps with the orthographic projection of the third insulating member 243, thereby increasing the coverage range of the third insulating member 243 and reducing the risk of the connection portion 2121 being overlapped with the second pole piece 22.

[0278] In some embodiments, the third insulating member 243 is an insulating coating layer arranged on the first end 2211.

[0279] For example, the insulating coating layer can be an inorganic non-metallic coating layer such as aluminum oxide, calcium oxide, etc.

[0280] For example, in the embodiments shown in FIGS. 22 and 23, the electrode assembly 2 includes a plurality of second pole pieces 22, and the plurality of second pole pieces 22 are arranged along the second direction Y, and one third insulating member 243 is arranged on the first end 2211 of each second pole piece 22. Along the second direction Y, the size of the third insulating member 243 is equal to the sum of the sizes of the second pole piece 22 and the two solid-state electrolyte layers 23.

[0281] In this embodiment, the third insulating member 243 is an insulating coating layer arranged on the first end 2211, and the third insulating member 243 of this structure has high connection strength with the second pole piece 22 and is not easy to be separated from the second pole piece 22.

[0282] In some embodiments, referring to FIG. 24 and FIG. 25, FIG. 24 is a structural schematic diagram of an electrode assembly 2 according to some embodiments of the present application; FIG. 25 is an enlarged view of a portion D in FIG. 24. The electrode assembly 2 includes a plurality of second electrode tabs 22 arranged along a second direction Y, a first electrode tab 21 arranged between two adjacent second electrode tabs 22, and a third insulating member 243 covering first ends 2211 of the plurality of second electrode tabs 22. The third insulating member 243 is provided with a plurality of hollow regions 2431, and a connecting portion 2121 of each first electrode lug 212 is arranged in a corresponding hollow region 2431.

[0283] For example, the electrode assembly 2 is a laminated structure.

[0284] The third insulating member 243 can be an insulating coating arranged on the first ends 2211 of the plurality of second electrode tabs 22, an insulating tape arranged on the first ends 2211 of the plurality of second electrode tabs 22, or an insulating support arranged on the first ends 2211 of the plurality of second electrode tabs 22. The insulating support can be made of rubber, plastic, or plastic, etc. The insulating support can be connected to or placed on the first ends 2211 of the plurality of first electrode tabs 21.

[0285] The hollow regions 2431 can be through holes or notched grooves arranged on the third insulating member 243. The notched grooves can extend through the third insulating member 243 along a first direction Z and extend to one edge of the third insulating member 243 along a third direction X.

[0286] The hollow regions 2431 of the third insulating member 243 allow the first electrode lug 212 to pass through, which facilitates the connection of the first electrode lug 212 to other components. One third insulating member 243 can achieve insulation isolation between the plurality of second electrode tabs 22 and the corresponding first electrode lug 212, which can effectively improve the arrangement efficiency of the third insulating member 243.

[0287] In some embodiments, referring to FIG. 26 and FIG. 27, FIG. 26 is a cross-sectional view of the third insulating member 243 shown in FIG. 25; FIG. 27 is an E-view of the third insulating member 243 shown in FIG. 26. The hollow regions 2431 include through holes extending through the third insulating member 243 along the first direction Z.

[0288] The through holes can have various shapes, such as circular holes, polygonal holes, etc. The polygonal holes can be triangular holes, quadrilateral holes, pentagonal holes, etc. For example, in the embodiments shown in FIG. 26 and FIG. 27, the through holes are rectangular holes.

[0289] By arranging the through holes on the third insulating member 243, the first electrode lug 212 can be conveniently passed through, and the first ends 2211 can be covered in a large area.

[0290] In some embodiments, referring to FIG. 28 and FIG. 29, FIG. 28 is a structural schematic diagram of an electrode assembly 2 according to some embodiments of the present application; and FIG. 29 is an enlarged view of a portion of FIG. 28. The insulating member 24 includes a first insulating member 241 and a third insulating member 243. In the first direction Z, at least a portion of the first insulating member 241 is disposed between the connecting portion 2121 and the first end 2211, and at least a portion of the third insulating member 243 is disposed between the connecting portion 2121 and the first end 2211. The first insulating member 241 is disposed on the first tab 212. The third insulating member 243 is disposed on the first end 2211 of the second tab 22.

[0291] The structure of the first insulating member 241 can refer to the first insulating member 241 in the foregoing embodiments, and the structure of the third insulating member 243 can refer to the third insulating member 243 in the foregoing embodiments, which will not be described herein.

[0292] In the present embodiment, the first insulating member 241 and the third insulating member 243 can both serve to insulate and separate the connecting portion 2121 and the second tab 22, thereby achieving multi-layer separation between the connecting portion 2121 and the second tab 22, and further reducing the risk of short circuit between the first tab 21 and the second tab 22 caused by the overlap of the connecting portion 2121 and the first end 2211.

[0293] In some embodiments, referring to FIG. 23, FIG. 25 and FIG. 29, in the first direction Z, the first body region 211 has a second end 2111, the first tab 212 is connected to the second end 2111, the second tab 22 includes a second overhanging region 2214 that exceeds the second end 2111, and the first end 2211 of the second overhanging region 2214 facing the connecting portion 2121 partially overlaps the solid-state electrolyte layer 23 in the projection plane perpendicular to the second direction Y.

[0294] The second overhanging region 2214 is a portion of the second body region 221 of the second tab 22 that exceeds the second end 2111. In the embodiment in which the solid-state electrolyte layer 23 has a first overhanging region 231 (not shown in FIG. 23, FIG. 25 and FIG. 29) that exceeds the second end 2111, the second overhanging region 2214 and the first overhanging region 231 are arranged in a stacked manner along the second direction Y. In addition, in the embodiment in which the portion of the first insulating member 241 between the first overhanging region 231 and the connecting portion 2121 along the second direction Y abuts against the first overhanging region 231 and the connecting portion 2121, the first insulating member 241 can reduce the risk of the solid-state electrolyte layer 23 and the second tab 22 being cracked or sheared by the edge of the first body region 211 at the second end 2111 during the forming of the electrode assembly 2.

[0295] As an example, along the first direction Z, the solid-state electrolyte layer 23 has a second end surface facing the connecting portion 2121, the second end surface is flush with the first end surface, and in a projection plane perpendicular to the second direction Y, a normal projection of the second overhanging region 2214 can overlap a normal projection of the first overhanging region 231.

[0296] In this embodiment, in a projection plane perpendicular to the second direction Y, a normal projection of the second overhanging region 2214 partially overlaps a normal projection of the solid-state electrolyte layer 23, which can increase the size of the solid-state electrolyte layer 23 along the first direction Z, so that the solid-state electrolyte layer 23 has a better separation effect between the first and second pole pieces 21 and 22.

[0297] Since the second overhanging region 2214 of the second pole piece 22 overhangs the second end 2111 of the first main body region 211, the first end 2211 of the second overhanging region 2214 has a greater risk of contacting the connecting portion 2121 of the first tab 212. However, by providing the insulating member 24 between the first end 2211 and the connecting portion 2121 of the first tab 212, the risk of the connecting portion 2121 and the first end 2211 being overlapped can be effectively reduced.

[0298] In some embodiments, the electrode assembly 2 is a stacked structure, and the electrode assembly 2 includes a plurality of first pole pieces 21 and a plurality of second pole pieces 22, and the plurality of first pole pieces 21 and the plurality of second pole pieces 22 are arranged in a stacked manner along the second direction Y.

[0299] As an example, along the second direction Y, the first pole pieces 21 and the second pole pieces 22 are arranged alternately, and the solid-state electrolyte layer 23 is arranged between adjacent first and second pole pieces 21 and 22, the number of second pole pieces 22 is one more than the number of first pole pieces 21, the second pole pieces 22 are negative pole pieces, the second tabs 222 are negative pole tabs, the first pole pieces 21 are positive pole pieces, and the first tabs 212 are positive pole tabs.

[0300] In this embodiment, the electrode assembly 2 is a stacked electrode assembly, which can achieve a higher volumetric energy density and has better thermal stability.

[0301] The embodiments of the present application provide a battery device 100, which includes the battery monomer 10 provided by any one of the embodiments.

[0302] The embodiments of the present application provide a power utilization device, which includes the battery monomer 10 provided by any one of the embodiments or the battery device 100 provided by any one of the embodiments, and the battery monomer 10 is used to provide electric energy.

[0303] In addition, referring to FIGS. 3-10, the embodiment of the present application provides a battery cell 10, which is a square cell. The battery cell 10 includes a housing 1 and an electrode assembly 2 accommodated in the housing 1. The electrode assembly 2 is a laminated electrode assembly, which includes a first electrode tab 21, a second electrode tab 22, a solid electrolyte layer 23, and a first insulating member 241. The first electrode tab 21 includes a first main body region 211 and a first tab 212. The first main body region 211 has a second end 2111 at which the first tab 212 is disposed. The second electrode tab 22 is opposite in polarity to the first electrode tab 21. The second electrode tab 22 has a first end 2211 close to the first tab 212 along a first direction Z. The first tab 212 includes a connection portion 2121 and a plurality of gathered portions 2122 connected in sequence. The gathered portions 2122 are connected to form a gathered region 25. The connection portion 2121 connects the gathered portions 2122 and the first main body region 211. The solid electrolyte layer 23 is disposed between the first electrode tab 21 and the second electrode tab 22 along a second direction Y perpendicular to the first direction Z. The first insulating member 241 is disposed at least partially between the connection portion 2121 and the first end 2211 along the first direction Z to insulate and separate the connection portion 2121 and the second electrode tab 22.

[0304] The first insulating member 241 is disposed on the connection portion 2121 of the first tab 212. The connection portion 2121 is bent to form a first connection portion 21211 and a second connection portion 21212 connected to each other. The first connection portion 21211 is connected to the gathered portions 2122, and the second connection portion 21212 is connected to the first main body region 211. The first connection portion 21211 is disposed opposite to the first end 2211 along the first direction Z. The first connection portion 21211 has a first surface 21211a facing the first end 2211. The second connection portion 21212 has a second surface 21212a facing the second electrode tab 22 along the second direction Y. The second surface 21212a is connected to the first surface 21211a. A portion of the first insulating member 241 is located between the first connection portion 21211 and the first end 2211 and covers at least a portion of the first surface 21211a. The first insulating member 241 covers at least a portion of the second surface 21212a. The first insulating member 241 is connected to the second end 2111 and extends along the extension direction of the first tab 212. The first insulating member 241 is an insulating tape or an insulating coating disposed on the first electrode tab 21.

[0305] In the battery cell 10, the first insulating member 241 can insulate and separate the connecting portion 2121 and the second tab 22 by being arranged on the connecting portion 2121 of the first tab 212 and at least partially between the connecting portion 2121 and the first end 2211, thereby reducing the risk of short circuit between the first tab 21 and the second tab 22 caused by the overlapping of the connecting portion 2121 and the first end 2211, and effectively improving the reliability of the battery cell 10.

[0306] Please refer to FIG. 22 and FIG. 23, the embodiment of the application provides a battery cell 10, the battery cell 10 is a square shell battery cell 10, the battery cell 10 comprises an outer shell 1 and an electrode assembly 2, the electrode assembly 2 is contained in the outer shell 1, the electrode assembly 2 is a laminated electrode assembly, the electrode assembly 2 comprises a first tab 21, a second tab 22, a solid-state electrolyte layer 23 and a third insulating member 243. The first tab 21 comprises a first main body region 211 and a first tab 212, along the first direction Z, the first main body region 211 has a second end 2111, and the first tab 212 is arranged at the second end 2111. The second tab 22 is opposite in polarity to the first tab 21, and along the first direction Z, the end of the second tab 22 close to the first tab 212 is a first end 2211. The first tab 212 comprises a connecting portion 2121 and a plurality of gathering portions 2122 connected in sequence, the plurality of gathering portions 2122 are connected to form a gathering region 25, and the connecting portion 2121 connects the gathering portion 2122 and the first main body region 211. The solid-state electrolyte layer 23 is arranged between the first tab 21 and the second tab 22 along the second direction Y, and the second direction Y is perpendicular to the first direction Z. The third insulating member 243 is at least partially arranged between the connecting portion 2121 and the first end 2211 along the first direction Z to insulate and separate the connecting portion 2121 and the second tab 22.

[0307] Among them, the third insulating member 243 is arranged on the second tab 22 and completely covers the first end 2211. Along the second direction Y, the two opposite surfaces of the second tab 22 are respectively provided with two solid-state electrolyte layers 23. In the projection plane perpendicular to the first direction Z, the orthographic projection of the two solid-state electrolyte layers 23 partially overlaps the orthographic projection of the third insulating member 243. The electrode assembly 2 comprises a plurality of second tabs 22 arranged along the second direction Y, a first tab 21 is arranged between any two adjacent second tabs 22, and each second tab 22 is correspondingly provided with a third insulating member 243. The third insulating member 243 is an insulating coating arranged on the first end 2211.

[0308] In the battery cell 10, the third insulating member 243 is arranged on the second tab 22 and covers the first end 2211, and the third insulating member 243 can insulate and separate the connecting portion 2121 and the second tab 22, thereby reducing the risk of short circuit between the first tab 21 and the second tab 22 caused by the connecting portion 2121 being overlapped with the first end 2211, and effectively improving the reliability of the battery cell 10.

[0309] Please refer to FIG. 24 and FIG. 25, the embodiment of the application provides a battery cell 10, the battery cell 10 is a square shell battery cell 10, the battery cell 10 comprises an outer shell 1 and an electrode assembly 2, the electrode assembly 2 is contained in the outer shell 1, the electrode assembly 2 is a laminated electrode assembly, the electrode assembly 2 comprises a first tab 21, a second tab 22, a solid-state electrolyte layer 23 and a third insulating member 243. The first tab 21 comprises a first main body region 211 and a first tab 212, along the first direction Z, the first main body region 211 has a second end 2111, and the first tab 212 is arranged on the second end 2111. The second tab 22 is opposite in polarity to the first tab 21, and along the first direction Z, the end of the second tab 22 close to the first tab 212 is a first end 2211. The first tab 212 comprises a plurality of gathering portions 2122 and a connecting portion 2121 connected in sequence, the plurality of gathering portions 2122 are connected to form a gathering region 25, and the connecting portion 2121 connects the gathering portion 2122 and the first main body region 211. The solid-state electrolyte layer 23 is arranged between the first tab 21 and the second tab 22 along the second direction Y, and the second direction Y is perpendicular to the first direction Z. The third insulating member 243 is arranged at least partially between the connecting portion 2121 and the first end 2211 along the first direction Z, so as to insulate and separate the connecting portion 2121 and the second tab 22.

[0310] Among them, the third insulating member 243 is arranged on the second tab 22 and completely covers the first end 2211. Along the second direction Y, the two opposite surfaces of the second tab 22 are respectively provided with two solid-state electrolyte layers 23. In the projection plane perpendicular to the first direction Z, the orthographic projection of the two solid-state electrolyte layers 23 partially overlaps the orthographic projection of the third insulating member 243. The electrode assembly 2 comprises a plurality of second tabs 22 arranged along the second direction Y, a first tab 21 is arranged between two adjacent second tabs 22, the third insulating member 243 covers the first end 2211 of the plurality of second tabs 22, the third insulating member 243 is an insulating support, the third insulating member 243 is provided with through holes penetrating through the third insulating member 243 along the first direction Z, and the connecting portion 2121 of the first tab 212 is arranged in the corresponding through hole.

[0311] In such a battery cell 10, by setting a third insulating member 243 on the second electrode 22, and by covering the first end 2211 of multiple second electrode 22s, the third insulating member 243 achieves insulation isolation between multiple second electrode 22s and the corresponding first electrode tab 212, reducing the risk of short circuit between the first electrode 21 and the second electrode 22, and effectively improving the reliability of the battery cell 10.

[0312] It should be noted that, unless otherwise specified, the embodiments and features described in this application can be combined with each other.

[0313] The above embodiments are only used to illustrate the technical solutions of this application and are not intended to limit this application. For those skilled in the art, this application can have various modifications and variations. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this application should be included within the protection scope of this application.

Claims

1. A battery cell, comprising: a housing; an electrode assembly accommodated in the housing, the electrode assembly comprising: a first tab comprising a first body region and a first tab lug, the first tab lug being disposed at one end of the first body region along a first direction, the first tab lug comprising a connection portion and a connecting portion connected in sequence, the connection portion being configured to connect with the connection portion of an adjacent first tab lug, and the connecting portion connecting the connection portion and the first body region; a second tab opposite in polarity to the first tab, the second tab having a first end proximate to one end of the first tab lug along the first direction; a solid-state electrolyte layer disposed between the first tab and the second tab along a second direction intersecting the first direction; an insulating member disposed at least partially between the connecting portion and the first end along the first direction to insulate and separate the connecting portion and the second tab.

2. The battery cell of claim 1, wherein, The insulating member comprises a first insulating member disposed at the connecting portion, at least a portion of the first insulating member being located between the connecting portion and the first end along the first direction.

3. The battery cell of claim 2, wherein, The connecting portion is bent to form a first connecting portion and a second connecting portion connected to each other, the first connecting portion being connected to the connection portion, and the second connecting portion being connected to the first body region, the first connecting portion being disposed opposite to the first end along the first direction, the first connecting portion having a first surface facing the first end, at least a portion of the first insulating member being located between the first connecting portion and the first end and covering at least a portion of the first surface.

4. The battery cell of claim 3, wherein, Along the second direction, the second connecting portion has a second surface facing the second tab, the second surface being connected to the first surface, and at least a portion of the first insulating member covering at least a portion of the second surface.

5. The battery cell of any one of claims 2-4, wherein, Along the first direction, the first body region has a second end, the first tab lug being connected to the second end, and the solid-state electrolyte layer comprising a first overhanging region beyond the second end; Along the second direction, a portion of the first insulating member is located between the first overhanging region and the connecting portion.

6. The battery cell of claim 5, wherein, Along the second direction, the portion of the first insulating member located between the first overhanging region and the connecting portion abuts against the first overhanging region and the connecting portion.

7. The battery cell of any one of claims 2-6, wherein, Along the first direction, the first body region has a second end, the first tab lug being connected to the second end; The first insulating member comprises a first insulating portion connected to the second end and extending along an extension direction of the first tab lug, at least a portion of the first insulating portion being located between the connecting portion and the first end along the first direction.

8. The battery cell of claim 7, wherein, Along the second direction, the first tab and the second tab are arranged alternately, the second tab being one more than the first tab, and along the extension direction of the first tab lug, the length of the first insulating portion is H, and Q≤H≤2Q; N is an even number, and Q=M1×N / 2+M2×(N-1) / 2+M3×(N-1); or N is an odd number, and Q=M1×(N-1) / 2+M2×(N-1) / 2+M3×(N-1); N is an even number, and Q=M1×N / 2+M2×(N-1) / 2+M3×(N-1); or N is an odd number, and Q=M1×(N-1) / 2+M2×(N-1) / 2+M3×(N-1); The number of the first tabs in the electrode assembly is N; the thickness of the first tab is M1, the thickness of the second tab is M2, and the thickness of the solid-state electrolyte layer is M3.

9. The battery cell of claim 7 or 8, wherein, The solid-state electrolyte layer includes a first overhanging region beyond the second end; In the second direction, a portion of the first insulating part is located between the first overhanging region and the connecting part and abuts against the first overhanging region and the connecting part.

10. The battery cell of claim 9, wherein, The first insulating part includes: A first part is arranged at the connecting part, and at least a portion of the first part is located between the connecting part and the first end in the first direction; A second part is connected to the first part, and the second part is connected to the second end. The thickness of the second part is greater than the thickness of the first part. In the second direction, at least a portion of the second part is located between the first overhanging region and the connecting part and abuts against the first overhanging region and the connecting part.

11. The battery cell of claim 10, wherein, In the first direction, the size of the second part is d, and the size of the first overhanging region is D, and 0.1≤d / D≤1.

12. The battery cell of claim 11, wherein, 2mm≤d≤10mm.

13. The battery cell of any one of claims 10-12, wherein, The first insulating part further includes a second insulating part connected to the second part. The thickness of the second insulating part is less than the thickness of the second part. In the second direction, the second insulating part is arranged in a stack with the first main region.

14. The battery cell of any one of claims 7-12, wherein, The first insulating part further includes a second insulating part connected to the first insulating part. In the second direction, the second insulating part is arranged in a stack with the first main region.

15. The battery cell of claim 14, wherein, The first main region includes: A first current collector layer connected to the first tab; A first active material layer located at an end of the first tab close to the second end in the first direction; in the second direction, a side of the first current collector layer facing the solid-state electrolyte layer is provided with the first active material layer, and the second insulating part is arranged in a stack with the first active material layer.

16. The battery cell of claim 15, wherein, The first active material layer includes: A main part; A thinned part arranged at an end of the main part close to the first tab in the first direction. The thickness of the thinned part is less than the thickness of the main part. In the second direction, the second insulating part is arranged in a stack with the thinned part.

17. The battery cell of claim 14, wherein, The first main region includes: A first current collector layer connected to the first tab; A first active material layer and an insulating layer arranged at an end of the first active material layer close to the first tab in the first direction. The end of the insulating layer close to the first tab in the first direction is located at the second end. In the second direction, a side of the first current collector layer facing the solid-state electrolyte layer is provided with the first active material layer and the insulating layer, and the second insulating part is arranged in a stack with the insulating layer.

18. The battery cell of any one of claims 13-17, wherein, In the first direction, the size of the second insulating part is a, and the size of the first main region is A, and 0.01≤a / A≤0.

05.

19. The battery cell of claim 18, wherein, 0.05mm≤a≤5mm.

20. The battery cell of any one of claims 13-19, wherein, In the second direction, the size of the second insulating part is b, and the size of the first main region is B, and 0.05≤b / B≤0.

25.

21. The battery cell of claim 20, wherein, 0.01mm≤b≤0.1mm.

22. The battery cell of any one of claims 2-21, wherein, The electrode assembly comprises a plurality of the first pole pieces arranged along the second direction, and the second pole piece is arranged between two adjacent first pole pieces; The gathering portions of the plurality of first pole pieces are connected to form a gathering area, the plurality of first pole pieces comprises two adjacent third pole pieces, the second pole piece between the two third pole pieces is arranged opposite to the gathering area along the first direction, and the projection of the first insulating member arranged on the two third pole pieces along the first direction collectively covers the first end of the second pole piece between the two third pole pieces.

23. The battery cell of claim 22, wherein, The plurality of first pole pieces further comprises a fourth pole piece, and the fourth pole piece is arranged along the second direction with the third pole piece; The projection of the first insulating member arranged on the fourth pole piece along the first direction covers the first end of the second pole piece adjacent to the fourth pole piece and located on the side of the fourth pole piece close to the gathering area.

24. The battery cell of claim 23, wherein, Along the second direction, the opposite surfaces of the second pole piece are respectively provided with two solid-state electrolyte layers; In the projection plane perpendicular to the first direction, the projection of the two solid-state electrolyte layers partially overlaps the projection of the first insulating member arranged on the fourth pole piece.

25. The battery cell of any one of claims 2-24, wherein, Along the third direction, the first insulating member exceeds at least one edge of the first tab, and the first direction, the second direction and the third direction are not coplanar and intersect with each other.

26. The battery cell of claim 25, wherein, Along the third direction, the first insulating member exceeds the opposite two edges of the first tab.

27. The battery cell of claim 25 or 26, wherein, Along the third direction, the size of the first insulating member is greater than the size of the first tab.

28. The battery cell of any one of claims 2-27, wherein, The insulating member comprises a second insulating member, and the first insulating member and the second insulating member are arranged on both sides of the first tab in the thickness direction.

29. The battery cell of claim 28, wherein, Along the third direction, the first insulating member and the second insulating member both exceed at least one edge of the first tab, and the first direction, the second direction and the third direction are not coplanar and intersect with each other; Wherein, the part of the first insulating member and the second insulating member exceeding the same edge of the first tab along the third direction is connected to each other.

30. The battery cell of any one of claims 2-29, wherein, The first insulating member is an insulating tape arranged on the first pole piece.

31. The battery cell of any one of claims 2-29, wherein, The first insulating member is an insulating coating arranged on the first pole piece.

32. The battery cell of any one of claims 1-31, wherein, The insulating member comprises a third insulating member, and the third insulating member is arranged on the second pole piece, and at least part of the third insulating member is arranged between the connecting portion and the first end along the first direction.

33. The battery cell of claim 32, wherein, The third insulating member completely covers the first end.

34. The battery cell of claim 32 or 33, wherein, Along the second direction, the opposite surfaces of the second pole piece are respectively provided with two solid-state electrolyte layers; In the projection plane perpendicular to the first direction, the projection of the two solid-state electrolyte layers partially overlaps the projection of the third insulating member.

35. The battery cell of any one of claims 32-34, wherein, The third insulating member is an insulating coating arranged on the first end.

36. The battery cell of any one of claims 32-35, wherein, The electrode assembly includes a plurality of the second tabs arranged along the second direction, the first tab is arranged between two adjacent second tabs, the third insulating member covers the first end of the plurality of second tabs, the third insulating member is provided with a hollow region, and the connecting portion of each first tab is arranged in the corresponding hollow region.

37. The battery cell of claim 36, wherein, The hollow region includes a through hole penetrating the third insulating member along the first direction.

38. The battery cell of any one of claims 1-37, wherein, Along the first direction, the first main body region has a second end, the first tab is connected to the second end, the second tab includes a second overhanging region beyond the second end, one end of the second overhanging region facing the connecting portion is the first end, and in a projection plane perpendicular to the second direction, the orthographic projection of the second overhanging region partially overlaps the orthographic projection of the solid-state electrolyte layer.

39. The battery cell of any one of claims 1-38, wherein, The electrode assembly is a laminated structure, and the electrode assembly includes a plurality of the first tabs and a plurality of the second tabs, the plurality of the first tabs and the plurality of the second tabs are arranged in a laminated manner along the second direction.

40. A battery device comprising the battery cell of any one of claims 1-39.

41. An electrically powered device comprising the battery cell of any one of claims 1-39 or the battery device of claim 40, the battery cell being configured to provide electrical power.

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