Electrode assembly, battery cell, battery and electric device

Abstract

The invention provides an electrode assembly, a battery monomer, a battery and a power utilization device. The electrode assembly comprises a first pole piece and a second pole piece which are opposite in polarity. The first pole piece comprises a first pole piece main body, the first pole piece main body comprises a first current collecting main body and a first active material layer, the first current collecting main body comprises two first surfaces which are oppositely arranged along the thickness direction of the first current collecting main body and a first end surface which is connected with the two first surfaces, and the first active material layer is arranged on the first surfaces. The electrode assembly further comprises an insulating part connected to the first pole piece body, at least part of the insulating part is arranged on the outer side of the first end face in the first direction, and the first direction is perpendicular to the thickness direction. The insulating part can separate the burrs on the first end face from the second pole piece, so that the risk of conduction between the burrs and the second pole piece is reduced, the possibility of thermal runaway caused by short circuit is reduced, and the reliability of the single battery is improved.

Description

[0001] Cross - Reference to Related Applications

[0002] This application claims the priority of the international patent application PCT / CN2024 / 073307 titled "Electrode Assembly, Battery Cell, Battery, and Electrical Device" filed on January 19, 2024, the entire content of which is incorporated herein by reference. Technical Field

[0003] This application relates to the field of battery technologies, and more particularly, to an electrode assembly, a battery cell, a battery, and an electrical device. Background Art

[0004] Battery cells are widely used in electronic devices, such as mobile phones, laptop computers, battery-powered vehicles, electric vehicles, electric airplanes, electric ships, electric toy cars, electric toy ships, electric toy airplanes, and power tools, etc.

[0005] In the development of battery technologies, how to improve the reliability of battery cells is a research direction in battery technologies. Summary of the Invention

[0006] This application provides an electrode assembly, a battery cell, a battery, and an electrical device, which can improve reliability.

[0007] In a first aspect, an embodiment of this application provides an electrode assembly, including a first electrode tab and a second electrode tab with opposite polarities. The first electrode tab includes a first electrode tab body, the first electrode tab body includes a first current collector body and a first active material layer, the first current collector body includes two first surfaces oppositely arranged along its own thickness direction and a first end face connecting the two first surfaces, and the first active material layer is disposed on the first surface. The electrode assembly further includes an insulating member connected to the first electrode tab body, and at least a part of the insulating member is disposed outside the first end face along a first direction, and the first direction is perpendicular to the thickness direction.

[0008] The insulating member can separate the burrs on the first end face from the second electrode tab, thereby reducing the risk of the burrs conducting with the second electrode tab, decreasing the possibility of thermal runaway caused by short circuit, and improving the reliability of the battery cell.

[0009] In one or more of the above optional embodiments, the insulating member includes two first insulating portions and a second insulating portion. The two first insulating portions are respectively located on both sides of the first electrode tab body along the thickness direction and are connected to the first electrode tab body. The second insulating portion connects the two first insulating portions and is disposed outside the first end face along the first direction.

[0010] By providing two first insulating portions, the connection area between the insulating member and the first electrode tab body can be increased, and the risk of the insulating member falling off can be reduced. The second insulating portion can separate the burrs on the first end face from the second electrode tab, thereby reducing the risk of short circuit.

[0011] In one or more of the above optional embodiments, the second insulating portion covers at least a part of the first end face to wrap the burrs on the first end face, thereby further reducing the risk of short circuit.

[0012] In one or more of the above optional embodiments, the first electrode tab further includes a first tab connected to the first current collector body. The first end face includes a tab lead-out area and a non-tab lead-out area. The first tab is only led out from the tab lead-out area and protrudes from the second insulating portion in a first direction away from the first current collector body. The first tab protrudes from the second insulating portion to facilitate connection with other conductive structures and reduce the risk of interference between the second insulating portion and the conductive structures.

[0013] In one or more of the above optional embodiments, the second insulating portion covers at least a part of the non-tab lead-out area. The second insulating portion can separate the burrs on the non-tab lead-out area from the second electrode tab, thereby reducing the risk of short circuit.

[0014] In one or more of the above optional embodiments, the second insulating portion is only provided on the outer side of the non-tab lead-out area in the first direction to reduce the amount of the insulating member used.

[0015] In one or more of the above optional embodiments, the second insulating portion includes a first extension portion and a second extension portion. The first extension portion is provided on the outer side of the non-tab lead-out area in the first direction, and the second extension portion is provided on the outer side of the tab lead-out area in the first direction and covers at least a part of the tab in the thickness direction.

[0016] The first extension portion can separate the burrs on the non-tab lead-out area from the second electrode tab, thereby reducing the risk of short circuit. The second extension portion can support the root of the first tab near the tab lead-out area, reduce the risk of the first tab being inserted between the first electrode tab and the second electrode tab when bent, and further reduce the risk of short circuit and improve the reliability.

[0017] In one or more of the above optional embodiments, the first extension portion covers the non-tab lead-out area in the first direction to block the burrs on the non-tab lead-out area.

[0018] In one or more of the above optional embodiments, the dimension of the first extension portion in the first direction is equal to the dimension of the second extension portion in the first direction. The second insulating portion is provided with equal width, which is easy to form.

[0019] In one or more of the above optional embodiments, the first extension portion is provided with a first part and a second part. The second part is connected to the second extension portion, and the dimension of the second part in the first direction is equal to the dimension of the second extension portion in the first direction. The first part is configured to be formed with a recess on the second insulating portion, and the dimension of the first part in the first direction is smaller than the dimension of the second extension portion in the first direction. By providing the recess, the dimension of the first part in the first direction can be reduced, thereby saving the amount of the insulating member and improving the energy density of the battery cell.

[0020] In one or more of the above optional embodiments, in the first direction, the dimension of the root region of the first tab covered by the second extension portion is greater than or equal to 0.2 times the dimension of the first tab. The second extension portion can provide effective support for the first tab, reduce the risk of the first tab being inserted upside down between the first electrode plate and the second electrode plate, and improve the reliability.

[0021] In one or more of the above optional embodiments, in the first direction, the dimension of the root region of the first tab covered by the second extension portion is less than or equal to 0.6 times the dimension of the first tab, so as to reduce the volume and weight of the insulating member and improve the energy density.

[0022] In one or more of the above optional embodiments, the first insulating portion is connected to the first active material layer, which can increase the connection area between the insulating member and the main body of the first electrode plate and reduce the risk of the insulating member falling off.

[0023] In one or more of the above optional embodiments, at least a part of the first insulating portion overlaps with the first active material layer in the thickness direction and is connected to the first active material layer to further increase the connection area between the first insulating portion and the main body of the first electrode plate.

[0024] In one or more of the above optional embodiments, the first active material layer includes a main body region arranged in the first direction and a thinning region connected to the main body region. The thinning region is located on one side of the main body region close to the first end face in the first direction, and at least part of the thickness of the thinning region is smaller than the thickness of the main body region. The first insulating portion covers at least part of the thinning region in the thickness direction.

[0025] By providing the thinning region, the pressure on the edge portion of the first active material layer during the rolling of the first electrode plate can be reduced, and the risk of cracking of the first current collector main body can be reduced. By arranging the first insulating portion in the space on one side of the thinning region in the thickness direction, the space utilization rate can be improved.

[0026] In one or more of the above optional embodiments, in the direction from the first current collector body towards the first active material layer, the first insulating portion does not extend beyond the surface of the main body region facing away from the first current collector body, so as to reduce the space additionally occupied by the first insulating portion in the thickness direction, improve the space utilization rate, and reduce the risk of the first insulating portion squeezing the second electrode sheet.

[0027] In one or more of the above optional embodiments, in the first direction, the first insulating portion is spaced apart from the main body region, so that the main body region and the first insulating portion do not overlap in the thickness direction, thereby improving the space utilization rate.

[0028] In one or more of the above optional embodiments, the first insulating portion covers a part of the main body region. The first insulating portion is simultaneously connected to the main body region and the thinning region, which can increase the connection area between the insulating member and the first electrode sheet main body and reduce the risk of the insulating member falling off.

[0029] In one or more of the above optional embodiments, the thickness t1 of the end portion of the thinning region away from the main body region is less than or equal to 0.5 times the thickness t2 of the main body region. The end portion of the thinning region away from the main body region has a smaller thickness, which can reduce the area covered by the second insulating portion, reduce the stress at the connection between the first insulating portion and the second insulating portion, and reduce the risk of the insulating member cracking and falling off.

[0030] In one or more of the above optional embodiments, the first surface includes a coating region and an uncoated region arranged in the first direction. One end of the uncoated region is connected to the first end face, and the other end is connected to the coating region. The coating region is coated with the first active material layer, and the uncoated region is not coated with the first active material layer. The first insulating portion is connected to the uncoated region.

[0031] By providing the uncoated region, the connection area between the first current collector body and the insulating member can be increased, the risk of the insulating member falling off can be reduced, and the reliability can be improved. The first end face and the first active material layer are spaced apart in the first direction, which can reduce the risk of cutting the first active material layer during the cutting process of the first electrode sheet and reduce the waste of the active material.

[0032] In one or more of the above optional embodiments, the first insulating portion completely covers the uncoated region to reduce the possibility of the uncoated region being electrically connected to the second electrode sheet, reduce the short - circuit risk, and improve the reliability.

[0033] In one or more of the above optional embodiments, in the first direction, the size of the region where the insulating member covers the uncoated region is greater than or equal to 1 mm, so as to increase the connection strength between the insulating member and the uncoated region and reduce the risk of the insulating member falling off from the first electrode sheet.

[0034] In one or more of the above optional embodiments, the first electrode tab body further includes an insulating coating, and at least a part of the insulating coating is disposed between the uncoated area and the first insulating portion. The insulating coating and the insulating member can achieve a double-insulation effect, thereby reducing the risk of short circuit.

[0035] In one or more of the above optional embodiments, the first electrode tab further includes a first tab, and the first tab extends outward from the first end face along the first direction and passes through the second insulating portion.

[0036] In one or more of the above optional embodiments, the insulating member includes two independently formed insulating layers, and each insulating layer includes an insulating main body and a connecting portion connected to the insulating main body; in the thickness direction, the insulating main body overlaps with the first electrode tab body, and the connecting portion does not overlap with the first electrode tab body. The insulating main bodies of the two insulating layers respectively form two first insulating portions; the connecting portions of the two insulating layers are stacked and connected to form the second insulating portion.

[0037] The two insulating layers can be attached to the first electrode tab body from both sides to form the insulating member, which helps to simplify the assembly process of the first electrode tab and the insulating member.

[0038] In one or more of the above optional embodiments, the thickness of the insulating layer is 7μm - 30μm. Limiting the thickness of the insulating layer to be greater than or equal to 7μm can reduce the risk of the insulating layer being pierced by burrs and improve the reliability. Limiting the thickness of the insulating layer to be less than or equal to 30μm can reduce the space and weight occupied by the insulating layer and reduce the loss of the energy density of the battery cell.

[0039] In one or more of the above optional embodiments, the insulation value of the difference between the thickness of the insulating layer and the thickness of the first current collector main body is not greater than 10μm. On the premise that the current-carrying capacity of the first current collector main body meets the requirements, the risk of the insulating layer being pierced by burrs is reduced, and the weight and space occupied by the insulating layer are reduced, thereby improving the energy density.

[0040] In one or more of the above optional embodiments, the insulation value of the difference between the thickness of the insulating layer and the thickness of the first current collector main body is not greater than 5μm.

[0041] In one or more of the above optional embodiments, the first electrode tab further includes a first tab connected to the first current collector main body. The first end face includes a tab lead-out area and a non-tab lead-out area. The first tab extends only from the tab lead-out area and protrudes from the second insulating portion in a direction away from the first current collector main body. The non-overlapping parts of the two connecting portions with the first tab are directly connected to form a first extension portion, and the first extension portion covers the non-tab lead-out area along the first direction. The overlapping parts of the two connecting portions with the first tab form a second extension portion and cover at least a part of the first tab in the thickness direction. The first extension portion can cover the non-tab lead-out area, thereby blocking the burrs on the non-tab lead-out area and reducing the risk of short circuit.

[0042] In one or more of the above optional embodiments, the dimension of the first extension portion in the first direction is equal to the dimension of the second extension portion in the first direction.

[0043] In one or more of the above optional embodiments, the insulating member is an integrally formed structure, which can enhance the stability of the connection between the insulating member and the first electrode tab body.

[0044] In one or more of the above optional embodiments, the first current collector body further includes two second end faces, the two second end faces are respectively arranged at both ends of the first end face, and each second end face connects the two first surfaces. The insulating member further includes a third insulating portion, and the third insulating portion is connected to the first insulating portion and the second insulating portion and covers a part of the second end face. The third insulating portion can cover the burrs on the second end face, thereby reducing the risk of short circuit and improving the reliability. By providing the third insulating portion, the risk of exposing the first end face due to assembly error can also be reduced.

[0045] In one or more of the above optional embodiments, the first current collector body includes two first end faces arranged opposite to each other in the first direction, and the first direction is perpendicular to the thickness direction of the first electrode tab body. The electrode assembly includes two insulating members, and the two insulating members are respectively arranged outside the two first end faces. The two insulating members can separate the burrs on the two first end faces from the second electrode tab, thereby further reducing the risk of short circuit.

[0046] In one or more of the above optional embodiments, the electrode assembly further includes a separator for separating the first electrode tab from the second electrode tab. In the first direction, the end of the second insulating portion away from the first insulating portion extends beyond the separator.

[0047] The second insulating portion protrudes from the separator. When the first electrode ear is bent, the second insulating portion can limit the first electrode ear, reduce the risk of the first electrode ear squeezing the separator, relieve the wrinkles of the separator, and reduce the risk of the separator shrinking inward, thereby improving the reliability.

[0048] In one or more of the above optional embodiments, the electrode assembly further includes a separator for separating the first electrode tab from the second electrode tab. In the first direction, the end of the second insulating portion away from the first insulating portion does not extend beyond the separator, so as to reduce the amount of the second insulating portion, reduce the weight and space occupied by the second insulating portion, and improve the energy density.

[0049] In one or more optional embodiments above, the second pole piece includes a second pole piece body, and the second pole piece body is stacked with the first pole piece body. The second pole piece body includes a second current collecting body and a second active material layer, and the second current collecting body includes two second surfaces arranged opposite to each other and a third end face connecting the two second surfaces, and the second active material layer is arranged on the second surface. The first end face is located at one end of the first current collecting body along the first direction, and the third end face is located at one end of the second current collecting body along the first direction. In the thickness direction, the insulating member separates the third end face from the first pole piece.

[0050] The insulating member can also separate the burrs on the third end surface from the first pole piece, thereby reducing the risk of the burrs on the third end surface being connected to the first pole piece, reducing the possibility of thermal runaway caused by short circuit, and improving the reliability of the battery cell.

[0051] In one or more optional embodiments above, the first pole piece is a positive pole piece, and the second pole piece is a negative pole piece. In the first direction, both ends of the second active material layer extend beyond the first pole piece body. The insulating member blocks at least a portion of the first end face, and even if the second active material layer overlaps with the first end face in the stacking direction, it is not easy to contact the burrs on the first end face. The second active material layer can provide more embedding sites for the active ions released from the first active material layer, thereby reducing the risk of active ion precipitation, improving the cycle performance of the battery cell, and improving reliability.

[0052] In one or more optional embodiments above, the melting point of the insulating member is 95° C.-150° C. During the charge and discharge process of the battery cell, the first current collector generates heat. The insulating member has a higher melting point, which can reduce the risk of the insulating member being softened and falling off by heat, thereby improving reliability.

[0053] In one or more optional embodiments above, the insulating member includes a colloid, and the colloid includes at least one of ethylene and its copolymers, polyolefins, polyesters, polyurethanes, polyamides, styrene and its block copolymers. The colloid has a high bonding strength and is not easy to fall off from the first pole piece body.

[0054] In one or more of the above optional embodiments, the insulating member includes a colloid, and the colloid is bonded to the first pole piece body. The colloid is configured not to undergo a redox reaction in a voltage range of 2.5V-4.5V. The colloid is not easily oxidized and failed in a voltage environment of 2.5V-4.5V, thereby reducing the risk of the insulating member falling off and improving reliability. In one or more of the above optional embodiments, the insulating member includes a substrate layer and an adhesive layer, and the substrate layer is connected to the first pole piece body through the adhesive layer. The substrate layer can enhance the strength of the insulating member and reduce the deformation of the insulating member during the attachment process. The adhesive layer can bond the substrate layer to the first pole piece body, reducing the risk of the substrate layer falling off from the first pole piece body.

[0055] In one or more optional embodiments above, the glue layer is configured to not undergo redox reaction in the voltage range of 2.5V-4.5V. The glue layer is configured to not undergo redox reaction in the voltage range of 2.5V-4.5V. The colloid is not easily oxidized and failed in the voltage environment of 2.5V-4.5V, thereby reducing the risk of insulation falling off and improving reliability.

[0056] In one or more optional embodiments above, the substrate layer includes at least one of polyethylene terephthalate, polypropylene, polyethylene and block copolymers thereof. The adhesive layer includes at least one of polyolefin, polyester, styrene-isobutylene copolymer, polyacrylate, styrene-butadiene rubber or butyl rubber.

[0057] In one or more optional embodiments above, the elastic modulus of the insulating member is 500Mpa-3000Mpa, and optionally, the elastic modulus of the insulating member is 770Mpa-1320Mpa. The insulating member has a high elastic modulus, which can provide support for the first pole lug, reduce the risk of the root of the first pole lug being inserted between the first pole piece and the second pole piece, and improve reliability.

[0058] In one or more of the above optional embodiments, the tensile strength of the insulating member is 949 kgf / cm 2 -1363kgf / cm 2 The insulating member has a high tensile strength and is not easily deformed when subjected to a tensile force from the first pole piece. Accordingly, the insulating member can effectively limit the deformation of the first pole piece, reduce the risk of the root of the first pole piece being inserted inverted between the first pole piece and the second pole piece, and improve reliability.

[0059] In one or more optional embodiments above, the insulating member is connected to the first active material layer. The peel strength between the insulating member and the first active material layer is higher than the peel strength between the first active material layer and the first surface. The peel strength between the insulating member and the first active material layer is high, thereby reducing the risk of the insulating member falling off and improving reliability.

[0060] In one or more optional embodiments above, the electrode assembly further includes a separator, which is used to separate the first pole piece from the second pole piece. The first pole piece, the separator, and the second pole piece are wound, and in the winding direction of the first pole piece, both ends of the insulating member do not exceed the separator. The separator can restrain the insulating member, keep the insulating member in contact with the main body of the first pole piece, and reduce the risk of the insulating member falling off the main body of the first pole piece.

[0061] In one or more of the above optional embodiments, the electrode assembly further includes a separator for separating the first electrode tab from the second electrode tab. The main body of the first electrode tab is flat. In the second direction perpendicular to the first direction and the thickness direction, both ends of the insulating member do not extend beyond the separator. The separator can restrain the insulating member to keep it in contact with the main body of the first electrode tab, reducing the risk of the insulating member detaching from the main body of the first electrode tab.

[0062] In one or more of the above optional embodiments, the first electrode tab is a positive electrode tab, the first active material layer includes a positive electrode active material, and the positive electrode active material includes a lithium transition metal oxide. The lithium transition metal oxide includes at least one of compounds with the chemical formula Li a Ni b Co c M d O e A f and their modified compounds, where 0.8 ≤ a ≤ 1.2, 0.3 ≤ b ≤ 0.96, 0 < c < 1, 0 < d < 1, 1 ≤ e ≤ 2, 0 ≤ f ≤ 1, M includes at least one of Mn, Al, Zr, Zn, Cu, Cr, Mg, Fe, V, Ti, and B, and A includes at least one of N, F, S, and Cl.

[0063] In one or more of the above optional embodiments, 0.5 ≤ b ≤ 0.9.

[0064] In one or more of the above optional embodiments, the first electrode tab is a positive electrode tab, the first active material layer includes a positive electrode active material, and the positive electrode active material includes a lithium nickel cobalt manganese oxide.

[0065] In one or more of the above optional embodiments, the lithium nickel cobalt manganese oxide is LiNi 1 / 3 Co 1 / 3 Mn 1 / 3 O2, LiNi 0.5 Co 0.2 Mn 0.3 O2, LiNi 0.5 Co 0.25 Mn 0.25 O2, L iNi 0.6 Co 0.2 Mn 0.2 O2, LiNi 0.8 Co 0.1 Mn 0.1 O2, LiNi 0.9 Co 0.05 Mn 0.05 O2, LiNi 0.92 Co 0.03 Mn 0.05 O2, LiNi 0.95Co 0.02 Mn 0.03 O2 or LiNi 0.96 Co 0.02 Mn 0.02 O2.

[0066] In one or more of the above optional embodiments, the puncture strength of the insulating member 14 is greater than or equal to 300 gf. The embodiments of the present application can reduce the risk of the insulating member being punctured by burrs, thereby reducing the risk of the burrs conducting with the second pole piece, reducing the possibility of thermal runaway caused by short circuit, and improving the reliability of the battery cell.

[0067] In a second aspect, an embodiment of the present application provides a battery cell, including a housing and an electrode assembly provided according to any one of the embodiments of the first aspect, and the electrode assembly is accommodated in the housing.

[0068] In one or more of the above optional embodiments, the housing includes a wall portion, and the wall portion is located on one side of the electrode assembly along the first direction. The battery cell further includes an insulating member, and the insulating member is disposed on the side of the wall portion facing the electrode assembly and fixed to the wall portion. A first end face is provided on the side of the first current collector body facing the wall portion. Along the direction from the electrode assembly to the wall portion, the insulating member protrudes from the first end face. In the first direction, the insulating member abuts against the insulating member. When the battery cell is subjected to an external impact, the insulating member can limit the vibration amplitude of the first pole piece in the first direction through the insulating member, reduce the damage of the first pole piece, and improve the reliability of the battery cell.

[0069] In a third aspect, an embodiment of the present application provides a battery, including a plurality of battery cells provided according to any one of the embodiments of the second aspect.

[0070] In a fourth aspect, an embodiment of the present application provides an electrical device, including a battery provided according to any one of the embodiments of the third aspect, and the battery is used to provide electrical energy. Description of the Drawings

[0071] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the following will briefly introduce the drawings required to be used in the embodiments of the present application. Obviously, the following described drawings are only some embodiments of the present application. For those of ordinary skill in the art, without creative efforts, other drawings can also be obtained according to the drawings.

[0072] Figure 1 Structural schematic diagram of a vehicle provided for some embodiments of the present application;

[0073] Figure 2 Explosion schematic diagram of a battery provided for some embodiments of the present application;

[0074] Figure 3Explosion schematic diagram of a battery cell provided by some embodiments of the present application;

[0075] Figure 4 Top view schematic diagram of an electrode assembly provided by some embodiments of the present application;

[0076] Figure 5 For Figure 4 Partial cross-sectional schematic diagram taken along the A-A direction;

[0077] Figure 6 Schematic diagram of the first electrode tab of the electrode assembly provided by some embodiments of the present application in a flattened state;

[0078] Figure 7 For Figure 6 Cross-sectional schematic diagram taken along the E-E direction;

[0079] Figure 8 For Figure 6 Schematic diagram at another angle;

[0080] Figure 9 For Figure 6 Schematic diagram of the first electrode tab shown after being connected to the insulating member;

[0081] Figure 10 Schematic diagram of an insulating member of the electrode assembly provided by some embodiments of the present application;

[0082] Figure 11 For Figure 9 Cross-sectional schematic diagram taken along the B-B direction;

[0083] Figure 12 For Figure 9 Cross-sectional view taken along the C-C direction;

[0084] Figure 13 For Figure 9 Schematic diagram of the first electrode tab and the insulating member shown at another angle;

[0085] Figure 14 Schematic diagram of the insulating layer of the electrode assembly provided by some embodiments of the present application in a flattened state;

[0086] Figure 15 Schematic diagram of the first electrode tab of the electrode assembly provided by some other embodiments of the present application in an unfolded state;

[0087] Figure 16 For Figure 15 Schematic diagram of the first electrode tab shown after being connected to the insulating member;

[0088] Figure 17 For Figure 16 Cross-sectional schematic diagram taken along the D-D direction;

[0089] Figure 18 Schematic diagram of the insulating part provided by some embodiments of the present application before being assembled to the first pole piece;

[0090] Figure 19 Schematic diagram of the first pole piece and the insulating part of the electrode assembly provided by some other embodiments of the present application in the unfolded state;

[0091] Figure 20 For Figure 19 Enlarged schematic diagram at the circular frame;

[0092] Figure 21 Schematic diagram of the structure of the insulating part of the electrode assembly provided by some embodiments of the present application;

[0093] Figure 22 Partial sectional view schematic diagram of the electrode assembly provided by some other embodiments of the present application;

[0094] Figure 23 Top view schematic diagram of the electrode assembly provided by some other embodiments of the present application;

[0095] Figure 24 For Figure 23 Cross-sectional schematic diagram taken along the F-F direction;

[0096] Figure 25 Cross-sectional view schematic diagram of the first pole piece and the insulating part of the electrode assembly provided by some other embodiments of the present application;

[0097] Figure 26 Schematic diagram of the electrode assembly provided by some other embodiments of the present application;

[0098] Figure 27 Schematic diagram of the first pole piece and the insulating part of the electrode assembly provided by some other embodiments of the present application in the unfolded state;

[0099] Figure 28 Schematic diagram of the first pole piece of the electrode assembly provided by some other embodiments of the present application in the unfolded state;

[0100] Figure 29 For Figure 28 Schematic diagram of the first pole piece shown after being connected to the insulating part;

[0101] Figure 30 For Figure 29 Cross-sectional view schematic diagram taken along the G-G direction;

[0102] Figure 31 Cross-sectional view schematic diagram of the battery cell provided by some embodiments of the present application;

[0103] Figure 32 For Figure 31An enlarged schematic diagram at the circular frame.

[0104] The reference numerals are as follows:

[0105] 1. Vehicle; 2. Battery; 3. Controller; 4. Motor; 5. Box; 5a. First box part; 5b. Second box part; 5c. Accommodating space; 6. Battery cell;

[0106] 10. Electrode assembly; 20. Outer shell; 20a. Wall part; 21. Housing; 22. End cover; 30. Electrode terminal; 40. Insulating member;

[0107] 11. First pole piece; 111. First pole piece main body; 112. First current collector main body; 1121. First surface; 1121a. Coated area; 1121b. Uncoated area; 1122. First end face; 1122a. Tab lead-out area; 1122b. Non-tab lead-out area; 1123. Second end face; 113. First active material layer; 1131. Main body area; 1132. Thinned area; 114. First tab; 115. Insulating coating;

[0108] 12. Second pole piece; 121. Second pole piece main body; 122. Second current collector main body; 1221. Second surface; 1222. Third end face; 123. Second active material layer; 124. Second tab;

[0109] 13. Separator;

[0110] 14. Insulator; 141. First insulating part; 142. Second insulating part; 1421. First extension part; 1421a. First part; 1421b. Second part; 1422. Second extension part; 142a. Channel; 143. Third insulating part; 144. Insulating layer; 144a. Insulating main body; 144b. Connecting part; 145. Substrate layer; 146. Adhesive layer; 147. Recess;

[0111] V. Winding direction; L. Length direction; X. Second direction; Y. Thickness direction; Z. First direction. Detailed implementation manners

[0112] To make the objectives, technical solutions, and advantages of the embodiments of the present application clearer, the technical solutions in the embodiments of the present application will be clearly described below with reference to the accompanying drawings in the embodiments of the present application. Obviously, the described embodiments are some, but not all, of the embodiments of the present application. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present application without creative efforts shall fall within the protection scope of the present application.

[0113] Unless otherwise defined, all technical and scientific terms used in this application have the same meaning as commonly understood by those skilled in the technical field to which this application belongs; the terms used in the specification of this application are only for the purpose of describing specific embodiments and are not intended to limit this application; the terms "including" and "having" and any variations thereof in the specification, claims and above-mentioned drawings of this application are intended to cover non-exclusive inclusion. The terms "first", "second", etc. in the specification, claims or above-mentioned drawings of this application are used to distinguish different objects and not to describe a specific order or primary-secondary relationship.

[0114] Reference to "embodiment" in this application means that a specific feature, structure or characteristic described in connection with the embodiment can be included in at least one embodiment of this application. The phrase appearing at various positions in the specification does not necessarily refer to the same embodiment, nor is it an independent or alternative embodiment mutually exclusive with other embodiments.

[0115] In the description of this application, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected", "coupled", "attached" shall be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection; it can be directly connected, or indirectly connected through an intermediate medium, and it can be the communication inside two components. For those of ordinary skill in the art, the specific meanings of the above terms in this application can be understood according to specific circumstances.

[0116] The term "and / or" in this application is merely a description of the association relationship of associated objects, indicating that three relationships can exist. For example, A and / or B can represent: A exists alone, A and B exist simultaneously, and B exists alone. In addition, the character " / " in this application generally represents an "or" relationship between the associated objects before and after.

[0117] In the embodiments of this application, the same reference numerals represent the same components, and for the sake of brevity, in different embodiments, the detailed description of the same components is omitted. It should be understood that the thickness, length, width and other dimensions of various components shown in the drawings in the embodiments of this application, as well as the overall thickness, length, width and other dimensions of the integrated device are only for illustrative purposes and should not constitute any limitation to this application.

[0118] The term "a plurality of" appearing in this application refers to two or more (including two).

[0119] In the embodiments of this application, the battery cell can be a secondary battery, and a secondary battery refers to a battery cell that can be activated by charging after discharging to continue to be used.

[0120] The battery cell may include, but is not limited to, a lithium-ion battery cell, a sodium-ion battery cell, a sodium-lithium-ion battery cell, a lithium-metal battery cell, a sodium-metal battery cell, a lithium-sulfur battery cell, a magnesium-ion battery cell, a nickel-metal hydride battery cell, a nickel-cadmium battery cell, a lead-acid battery cell, etc.

[0121] As an example, the battery cell may be a cylindrical battery cell, a prismatic battery cell, or a battery cell of other shapes. The prismatic battery cell includes a square-shell battery cell, a blade-shaped battery cell, a multi-prismatic battery, and the multi-prismatic battery is, for example, a hexagonal-prismatic battery, etc. There is no special limitation in this application.

[0122] The battery mentioned in the embodiments of this application refers to a single physical module that includes one or more battery cells to provide a higher voltage and capacity.

[0123] In some embodiments, the battery may be a battery module. When there are multiple battery cells, the multiple battery cells are arranged and fixed to form a battery module.

[0124] In some embodiments, the battery may be a battery pack. The battery pack includes a box body and battery cells, and the battery cells or battery modules are accommodated in the box body.

[0125] In some embodiments, the box body may be part of the chassis structure of a vehicle. For example, part of the box body may become at least part of the floor of the vehicle, or part of the box body may become at least part of the crossbeam and longitudinal beam of the vehicle.

[0126] In some embodiments, the battery may be an energy storage device. The energy storage device includes an energy storage container, an energy storage cabinet, etc.

[0127] The battery cell generally includes an electrode assembly and a housing, and the electrode assembly is accommodated in the housing. The electrode assembly includes a positive electrode, a negative electrode, and a separator. During the charge and discharge process of the battery cell, active ions (such as lithium ions) are embedded and extracted back and forth between the positive electrode and the negative electrode. The separator is disposed between the positive electrode and the negative electrode, which can reduce the risk of short circuit between the positive and negative electrodes and at the same time allow the active ions to pass through.

[0128] The housing is used to encapsulate components such as the electrode assembly and the electrolyte. The housing can be a steel shell, an aluminum shell, a plastic shell (such as polypropylene), a composite metal shell (such as a copper-aluminum composite housing), or an aluminum-plastic film, etc.

[0129] In some embodiments, the positive electrode may be a positive electrode plate, and the positive electrode plate may include a positive electrode current collector and a positive electrode active material layer provided on at least one surface of the positive electrode current collector. The negative electrode may be a negative electrode plate, and the negative electrode plate may include a negative electrode current collector and a negative electrode active material layer provided on at least one surface of the negative electrode current collector.

[0130] During the preparation of the electrode sheet (positive electrode sheet or negative electrode sheet), it is usually necessary to perform cutting (such as electrode sheet slitting process or tab die-cutting process) to form the required size and shape. However, after cutting, burrs are likely to occur at the cutting position of the current collector; during the charging and discharging process of the battery cell, the burrs may pierce the separator and conduct the positive and negative electrodes, triggering a short-circuit risk and affecting the reliability of the battery cell.

[0131] In view of this, the embodiments of the present application provide a technical solution, which blocks the burrs on the end face of the current collector by arranging an insulating member on the electrode sheet, thereby reducing the risk of the burrs conducting the positive and negative electrodes and improving the reliability of the battery cell.

[0132] The electrode assembly described in the embodiments of the present application is applicable to battery cells, batteries, and electrical devices using batteries.

[0133] The battery disclosed in the embodiments of the present application can be used in electrical devices using the battery as a power source or various energy storage systems using the battery as an energy storage element. The electrical device can be, but is not limited to, a mobile phone, a tablet computer, a laptop computer, an electric toy, an electric tool, a battery car, an electric vehicle, a ship, a spacecraft, etc. Among them, the electric toy can include fixed or mobile electric toys, such as game consoles, electric vehicle toys, electric ship toys, and electric aircraft toys, etc., and the spacecraft can include airplanes, rockets, space shuttles, and spaceships, etc.

[0134] For the convenience of description, the following embodiments take the electrical device as a vehicle as an example for illustration.

[0135] Figure 1 It is a schematic structural diagram of a vehicle provided by some embodiments of the present application.

[0136] As Figure 1 shown, a battery 2 is arranged inside the vehicle 1, and the battery 2 can be arranged at the bottom, head, or tail of the vehicle 1. The battery 2 can be used for the power supply of the vehicle 1. For example, the battery 2 can be used as the operating power source of the vehicle 1.

[0137] The vehicle 1 may further include a controller 3 and a motor 4. The controller 3 is used to control the battery 2 to supply power to the motor 4. For example, it is used for the working power requirements during the start, navigation, and driving of the vehicle 1.

[0138] In some embodiments of the present application, the battery 2 can not only be used as the operating power source of the vehicle 1, but also be used as the driving power source of the vehicle 1, replacing or partially replacing fuel or natural gas to provide driving power for the vehicle 1.

[0139] Figure 2 It is an explosion schematic diagram of a battery provided by some embodiments of the present application. As Figure 2As shown, the battery 2 includes a housing 5 and battery cells 6, and the battery cells 6 are accommodated in the housing 5.

[0140] The housing 5 is used to accommodate the battery cells 6, and the housing 5 can have various structures. In some embodiments, the housing 5 can include a first housing part 5a and a second housing part 5b. The first housing part 5a and the second housing part 5b cover each other, and the first housing part 5a and the second housing part 5b together define an accommodation space 5c for accommodating the battery cells. The second housing part 5b can be a hollow structure with an open end, and the first housing part 5a is a plate-like structure. The first housing part 5a covers the open side of the second housing part 5b to form the housing 5 with the accommodation space 5c; both the first housing part 5a and the second housing part 5b can also be hollow structures with an open side, and the open side of the first housing part 5a covers the open side of the second housing part 5b to form the housing 5 with the accommodation space 5c. Of course, the first housing part 5a and the second housing part 5b can have various shapes, such as a cylinder, a cuboid, etc.

[0141] To improve the sealing performance after the connection between the first housing part 5a and the second housing part 5b, a sealing member can also be provided between the first housing part 5a and the second housing part 5b, such as sealant, sealing ring, etc.

[0142] Assume that the first housing part 5a covers the top of the second housing part 5b. The first housing part 5a can also be called the upper cover, and the second housing part 5b can also be called the lower housing.

[0143] In the battery 2, the battery cells 6 can be one or multiple. If there are multiple battery cells 6, the multiple battery cells 6 can be connected in series, in parallel, or in a mixed connection. A mixed connection means that there are both series and parallel connections among the multiple battery cells 6. The multiple battery cells 6 can be directly connected in series, in parallel, or in a mixed connection together, and then the whole formed by the multiple battery cells 6 is accommodated in the housing 5; of course, it can also be that multiple battery cells are first connected in series, in parallel, or in a mixed connection to form battery modules, and then the multiple battery modules are connected in series, in parallel, or in a mixed connection to form a whole and are accommodated in the housing 5.

[0144] Exemplarily, a battery cell can be the smallest unit that makes up a battery.

[0145] Figure 3 This is an exploded view of the battery cell provided in some embodiments of the present application.

[0146] As Figure 3 shown, in some embodiments, the battery cell 6 includes a housing 20 and an electrode assembly 10 accommodated in the housing 20.

[0147] The electrode assembly 10 includes a positive electrode and a negative electrode. During the charging and discharging process of the battery cell 6, active ions (such as lithium ions) are intercalated and deintercalated back and forth between the positive electrode and the negative electrode. Optionally, the electrode assembly 10 further includes a separator disposed between the positive electrode and the negative electrode, and the separator can reduce the risk of short circuit between the positive and negative electrodes and allow the active ions to pass through.

[0148] The outer shell 20 is used to encapsulate components such as the electrode assembly 10 and the electrolyte. The outer shell 20 can be a steel shell, an aluminum shell, a plastic shell (such as polypropylene), a composite metal shell (such as a copper-aluminum composite outer shell 20), or an aluminum plastic film, etc.

[0149] In some embodiments, the outer shell 20 includes a housing 21 and an end cap 22. The housing 21 has an opening, and the end cap 22 is used to cover the opening.

[0150] The housing 21 is a component for cooperating with the end cap 22 to form the internal cavity of the battery cell 6. The formed internal cavity can be used to accommodate the electrode assembly 10, the electrolyte, and other components.

[0151] The housing 21 and the end cap 22 can be independent components. Exemplarily, an opening can be provided on the housing 21, and the end cap 22 is covered at the opening to form the internal cavity of the battery cell 6.

[0152] The housing 21 can be of various shapes and sizes, such as cuboid, cylindrical, hexagonal prism, etc. Specifically, the shape of the housing 21 can be determined according to the specific shape and size of the electrode assembly 10. The material of the housing 21 can be various. For example, the material of the housing 21 includes but is not limited to copper, iron, aluminum, stainless steel, aluminum alloy, aluminum plastic film, steel plastic film, etc.

[0153] The shape of the end cap 22 can be adapted to the shape of the housing 21 to cooperate with the housing 21. The material of the end cap 22 can be the same as or different from that of the housing 21. Optionally, the end cap 22 can be made of a material with a certain hardness and strength (such as copper, iron, aluminum, stainless steel, aluminum alloy, plastic, etc.). In this way, the end cap 22 is not easily deformed when being squeezed or collided, enabling the battery cell 6 to have higher structural strength and improved reliability.

[0154] The end cap 22 is connected to the housing 21 by welding, bonding, clamping, or other means.

[0155] The housing 21 can be open at one end or both ends. In some examples, the housing 21 can be a structure with one side open, and the end cap 22 is provided as one and covers the housing 21. In other examples, the housing 21 can also be a structure with both sides open, and the end cap 22 is provided as two, and the two end caps 22 respectively cover the two openings of the housing 21.

[0156] In some embodiments, the battery cell 6 includes an electrode terminal 30. The electrode terminal 30 is electrically connected to the electrode assembly 10 for outputting or inputting the electrical energy of the battery cell 6.

[0157] In some embodiments, the battery cell 6 further includes an electrolyte accommodated in the housing 20. The electrolyte functions to conduct ions between the positive and negative electrodes. The electrolyte can be liquid, gel-state or solid-state.

[0158] In some embodiments, the liquid electrolyte includes an electrolyte salt and a solvent.

[0159] In some embodiments, the electrolyte salt may include at least one of lithium hexafluorophosphate, lithium tetrafluoroborate, lithium perchlorate, lithium hexafluoroarsenate, lithium bis(fluorosulfonyl)imide, lithium bis(trifluoromethanesulfonyl)imide, lithium trifluoromethanesulfonate, lithium difluorophosphate, lithium difluoro(oxalato)borate, lithium bis(oxalato)borate, lithium difluoro(bis(oxalato))phosphate, and lithium tetrafluoro(oxalato)phosphate.

[0160] In some embodiments, the solvent may include at least one of ethylene carbonate, propylene carbonate, ethyl methyl carbonate, diethyl carbonate, dimethyl carbonate, dipropyl carbonate, methyl propyl carbonate, ethyl propyl carbonate, butylene carbonate, fluoroethylene carbonate, methyl formate, methyl acetate, ethyl acetate, propyl acetate, methyl propionate, ethyl propionate, propyl propionate, methyl butyrate, ethyl butyrate, 1,4-butyrolactone, sulfolane, dimethyl sulfone, methyl ethyl sulfone, and diethyl sulfone. The solvent can also be an ether solvent. The ether solvent can include one or more of ethylene glycol dimethyl ether, ethylene glycol diethyl ether, diethylene glycol dimethyl ether, triethylene glycol dimethyl ether, tetraethylene glycol dimethyl ether, 1,3-dioxolane, tetrahydrofuran, methyltetrahydrofuran, diphenyl ether, and crown ether.

[0161] In some embodiments, the gel-state electrolyte includes a polymer as the skeleton network of the electrolyte, combined with an ionic liquid-lithium salt.

[0162] In some embodiments, the solid electrolyte includes a polymer solid electrolyte, an inorganic solid electrolyte, and a composite solid electrolyte.

[0163] As an example, the polymer solid electrolyte can be polyether (polyethylene oxide), polysiloxane, polycarbonate, polyacrylonitrile, polyvinylidene fluoride, polymethyl methacrylate, single-ion polymer, poly(ionic liquid)-lithium salt, cellulose, etc.

[0164] As an example, the inorganic solid electrolyte can be an oxide solid electrolyte (crystalline perovskite, sodium superionic conductor, garnet, amorphous LiPON film), a sulfide solid electrolyte (crystalline lithium superionic conductor (lithium germanium phosphorus sulfur, argyrodite), amorphous sulfide), and one or more of a halide solid electrolyte, a nitride solid electrolyte, and a hydride solid electrolyte.

[0165] As an example, a composite solid electrolyte is formed by adding an inorganic solid electrolyte filler to a polymer solid electrolyte.

[0166] Figure 4 A top view schematic diagram of the electrode assembly provided by some embodiments of the present application; Figure 5 is Figure 4 A partial cross-sectional schematic diagram taken along the A-A direction.

[0167] Referring to Figure 4 and Figure 5 The electrode assembly 10 of the embodiment of the present application includes a first pole piece 11 and a second pole piece 12 with opposite polarities.

[0168] Exemplarily, one of the first pole piece 11 and the second pole piece 12 is a positive electrode piece, and the other is a negative electrode piece.

[0169] In some embodiments, the positive electrode piece may include a positive electrode current collector and a positive electrode active material layer provided on at least one surface of the positive electrode current collector.

[0170] As an example, the positive electrode current collector has two surfaces opposite to each other in its own thickness direction, and the positive electrode active material layer is provided on any one or both of the two opposite surfaces of the positive electrode current collector.

[0171] As an example, the positive electrode current collector can be made of carbon, metal foil, or a composite current collector. For example, as the metal foil, stainless steel, copper, aluminum, nickel, carbon electrode, nickel, titanium, aluminum or stainless steel with silver surface treatment, etc. can be used. The composite current collector may include a polymer material base layer and a metal layer. The composite current collector can be formed by forming a metal material (such as aluminum, aluminum alloy, nickel, nickel alloy, titanium, titanium alloy, silver, and silver alloy, etc.) on a polymer material substrate (such as substrates of polypropylene, polyethylene terephthalate, polybutylene terephthalate, polystyrene, polyethylene, etc.).

[0172] As an example, the positive electrode active material layer includes a positive electrode active material, which may include at least one of the following materials: lithium-containing phosphates, lithium transition metal oxides, and their respective modified compounds. Other conventional materials that can be used as the positive electrode active material layer of the battery can also be used for the positive electrode active material. These positive electrode active materials can be used alone or in combination of two or more. Examples of lithium-containing phosphates may include, but are not limited to, lithium iron phosphate (such as LiFePO4 (which can also be abbreviated as LFP)), a composite material of lithium iron phosphate and carbon, lithium manganese phosphate (such as LiMnPO4), a composite material of lithium manganese phosphate and carbon, lithium manganese iron phosphate, a composite material of lithium manganese iron phosphate and carbon, etc. Examples of lithium transition metal oxides may include, but are not limited to, lithium cobalt oxide (such as LiCoO2), lithium nickel oxide (such as LiNiO2), lithium manganese oxide (such as LiMnO2, LiMn2O4), lithium nickel cobalt oxide, lithium manganese cobalt oxide, lithium nickel manganese oxide, lithium nickel cobalt manganese oxide (such as LiNi 1 / 3 Co 1 / 3Mn 1 / 3 O2 (which can also be abbreviated as NCM333), LiNi 0.5 Co 0.2 Mn 0.3 O2 (which can also be abbreviated as NCM523), LiNi 0.5 Co 0.25 Mn 0.25 O2 (which can also be abbreviated as NCM211), LiNi 0.6 Co 0.2 Mn 0.2 O2 (which can also be abbreviated as NCM622), LiNi 0.8 Co 0.1 Mn 0.1 O2 (which can also be abbreviated as NCM811), lithium nickel cobalt aluminum oxide (such as LiNi 0.80 Co 0.15 Al 0.05 O2) and their modified compounds, etc.

[0173] In some embodiments, the negative electrode sheet may include a negative electrode current collector and a negative electrode active material layer provided on at least one surface of the negative electrode current collector.

[0174] As an example, the negative electrode current collector can be a metal foil, a foam metal, or a composite current collector. For example, as the metal foil, aluminum or stainless steel with a silver surface treatment, stainless steel, copper, aluminum, nickel, carbon electrodes, nickel, or titanium, etc. can be used. The foam metal can be nickel foam, copper foam, aluminum foam, foam alloy, or foam carbon, etc. 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 (such as copper, copper alloy, nickel, nickel alloy, titanium, titanium alloy, silver, and silver alloy, etc.) on a polymer material substrate (such as substrates of polypropylene, polyethylene terephthalate, polybutylene terephthalate, polystyrene, polyethylene, etc.).

[0175] As an example, the negative electrode active material layer includes a negative electrode active material. The negative electrode active material can be the negative electrode active material for battery monomers known in the art. As an example, the negative electrode active material can include at least one of the following materials: artificial graphite, natural graphite, soft carbon, hard carbon, silicon-based materials, tin-based materials, and lithium titanate, etc. The silicon-based materials can include at least one of elemental silicon, silicon oxides, silicon-carbon composites, silicon-nitrogen composites, and silicon alloys. The tin-based materials can include at least one of elemental tin, tin oxides, and tin alloys. The negative electrode active material of the present application can also use other conventional materials that can be used as battery negative electrode active materials. These negative electrode active materials can be used alone or in combination of two or more.

[0176] In some embodiments, the material of the positive electrode current collector can be aluminum, and the material of the negative electrode current collector can be copper.

[0177] In some embodiments, the electrode assembly 10 further includes a separator 13, and the separator 13 is used to separate the first electrode sheet 11 and the second electrode sheet 12. The separator 13 can reduce the risk of short circuit between the positive and negative electrodes, and at the same time allow active ions to pass through.

[0178] In some embodiments, the separator 13 includes a separator membrane. The separator membrane of the present application can be any known porous structure separator membrane with good chemical stability and mechanical stability.

[0179] As an example, the main materials of the separator membrane can include at least one of glass fiber, non-woven fabric, polyethylene, polypropylene, polyvinylidene fluoride, and ceramics. The separator membrane can be a single-layer film or a multi-layer composite film. When the separator membrane is a multi-layer composite film, the materials of each layer can be the same or different. The separator 13 can be a separate component located between the positive and negative electrodes, or can be attached to the surfaces of the positive and negative electrodes.

[0180] In some embodiments, the separator 13 is a solid electrolyte. The solid electrolyte is disposed between the positive electrode sheet and the negative electrode sheet, and at the same time plays the role of transmitting ions and isolating the positive and negative electrodes.

[0181] In some embodiments, the electrode assembly 10 has a wound structure. Exemplarily, both the first electrode tab 11 and the second electrode tab 12 are strip-shaped structures, and the first electrode tab 11, the separator 13, and the second electrode tab 12 are wound into a wound structure.

[0182] In some embodiments, the electrode assembly 10 has a stacked structure.

[0183] As an example, multiple first electrode tabs 11 and multiple second electrode tabs 12 can be respectively provided, and the multiple first electrode tabs 11 and the multiple second electrode tabs 12 are alternately stacked.

[0184] As an example, multiple first electrode tabs 11 can be provided, and the second electrode tab 12 is folded to form multiple folded segments arranged in a stacked manner, and one first electrode tab 11 is clamped between adjacent folded segments.

[0185] As an example, both the first electrode tab 11 and the second electrode tab 12 are folded to form multiple folded segments arranged in a stacked manner.

[0186] As an example, multiple separators 13 can be provided and are respectively arranged between any adjacent first electrode tabs 11 or second electrode tabs 12.

[0187] As an example, the separator 13 can be continuously provided and is arranged between any adjacent first electrode tabs 11 or second electrode tabs 12 by means of folding or winding.

[0188] In some embodiments, the shape of the electrode assembly 10 can be cylindrical, flat, prismatic, or the like.

[0189] Figure 6 Schematic diagram of the first electrode tab of the electrode assembly provided in some embodiments of the present application in a flattened state; Figure 7 is Figure 6 a cross-sectional schematic diagram taken along the E-E direction; Figure 8 is Figure 6 a schematic diagram from another angle; Figure 9 is Figure 6 schematic diagram of the first electrode tab shown after being connected to the insulating member, wherein the portion of the first electrode tab covered by the insulating member is shown by a dashed line; Figure 10 Schematic diagram of an insulating member of the electrode assembly provided in some embodiments of the present application; Figure 11 is Figure 9 a cross-sectional schematic diagram taken along the B-B direction; Figure 12 is Figure 9 a cross-sectional view taken along the C-C direction; Figure 13 is Figure 9 schematic diagram of the first electrode tab and the insulating member shown from another angle; Figure 14 Schematic diagram of the insulating layer of the electrode assembly provided in some embodiments of the present application in a flattened state, wherein the boundary between the insulating main body and the connecting portion is shown by a dashed line.

[0190] Please refer to Figures 4 to 14 , the embodiment of the present application provides an electrode assembly 10, which includes a first pole piece 11 and a second pole piece 12 with opposite polarities.

[0191] The first pole piece 11 includes a first pole piece body 111. The first pole piece body 111 includes a first current collector body 112 and a first active material layer 113. The first current collector body 112 includes two first surfaces 1121 oppositely arranged along its thickness direction Y and a first end face 1122 connecting the two first surfaces 1121. The first active material layer 113 is disposed on the first surface 1121.

[0192] In some examples, the first pole piece 11 is a positive electrode piece. The positive electrode current collector may include the first current collector body 112, and the first active material layer 113 is a positive electrode active material layer. In other examples, the first pole piece 11 is a negative electrode piece, the negative electrode current collector includes the first current collector body 112, and the first active material layer 113 is a negative electrode active material layer.

[0193] The first active material layer 113 may be integrally disposed on the first surface 1121. Alternatively, a part of the first active material layer 113 may also be disposed at other positions. For example, the first pole piece 11 further includes a first tab 114 connected to the first current collector body 112, and a part of the first active material layer 113 may be disposed at the root of the first tab 114 close to the first current collector body 112.

[0194] In the embodiment of the present application, the first active material layer 113 may be disposed on one of the first surfaces 1121, or may be disposed on both of the first surfaces 1121.

[0195] Exemplarily, the first current collector body 112 has a relatively small thickness, the first end face 1122 has a relatively small dimension in the thickness direction Y of the first pole piece body 111, and the first end face 1122 may be approximated as a line. Optionally, the thickness of the first current collector body 112 is 2μm - 30μm. Optionally, the thickness of the first current collector body 112 is 5μm - 15μm.

[0196] Exemplarily, at least a part of the first end face 1122 is formed in the cutting process of the first pole piece 11.

[0197] In some embodiments, the electrode assembly 10 further includes an insulating member 14 connected to the first pole piece body 111. At least a part of the insulating member 14 is disposed outside the first end face 1122 along the first direction Z, and the first direction Z is perpendicular to the thickness direction Y.

[0198] Exemplarily, "at least part of the insulating member 14 is disposed outside the first end face 1122 along the first direction Z" does not require the insulating member 14 to overlap with the first end face 1122 in the first direction Z. As long as at least part of the insulating member 14 protrudes from the first end face 1122 in the first direction Z. Exemplarily, a part of the insulating member 14 is located on one side of the first current collector body 111 in the thickness direction Y, and in the first direction Z, the insulating member 14 protrudes from the first end face 1122.

[0199] Exemplarily, at least part of the first end face 1122 overlaps with the insulating member 14 in the thickness direction.

[0200] The first current collector body 112 may be provided with one first end face 1122, or may be provided with a plurality of first end faces 1122. Optionally, the first current collector body 112 has a plurality of first end faces 1122, and insulating members 14 are correspondingly arranged outside each first end face 1122.

[0201] The insulating member 14 may be directly connected to the first active material layer 113, may be directly connected to the first current collector body 112, or may be directly connected to both the first active material layer 113 and the first current collector body 112 at the same time.

[0202] The insulating member 14 may be an integrally formed structure. Alternatively, the insulating member 14 may be assembled from at least two independently formed components.

[0203] There may be one or a plurality of insulating members 14.

[0204] The insulating member 14 may be connected to the first current collector body 111 in various ways. For example, the insulating member 14 may be connected to the first current collector body 111 by bonding; alternatively, the insulating member 14 may not be bonded to the first current collector body 111, but may be connected to the first current collector body 111 by attaching.

[0205] In the embodiment of the present application, the insulating member 14 can separate the burrs on the first end face 1122 from the second electrode plate 12, thereby reducing the risk of the burrs conducting with the second electrode plate 12, reducing the possibility of thermal runaway caused by short circuit, and improving the reliability of the battery cell 6.

[0206] Exemplarily, the insulating member 14 can separate the burrs from the separator 13, reducing the risk of the burrs piercing the separator 13.

[0207] In some embodiments, the insulating member 14 includes two first insulating portions 141 and a second insulating portion 142. The two first insulating portions 141 are respectively located on both sides of the first electrode tab body 111 in the thickness direction Y and are connected to the first electrode tab body 111. The second insulating portion 142 connects the two first insulating portions 141 and is disposed outside the first end face 1122 in the first direction Z.

[0208] Exemplarily, in the thickness direction Y, the projection of the first insulating portion 141 is located within the projection of the first electrode tab body 111, and the projection of the second insulating portion 142 does not overlap with the projection of the first electrode tab body 111.

[0209] The shapes of the two first insulating portions 141 may be the same or different.

[0210] The first insulating portion 141 may be connected to the first active material layer 113 or may be connected to the first current collector body 112.

[0211] By providing the two first insulating portions 141, the connection area between the insulating member 14 and the first electrode tab body 111 can be increased, and the risk of the insulating member 14 falling off can be reduced. The second insulating portion 142 can separate the burrs on the first end face 1122 from the second electrode tab, thereby reducing the short - circuit risk.

[0212] In some embodiments, the second insulating portion 142 covers at least a part of the first end face 1122 to cover the burrs on the first end face 1122, thereby further reducing the short - circuit risk.

[0213] In the first direction, the second insulating portion 142 at least partially overlaps with the first end face 1122 to cover at least a part of the first end face 1122.

[0214] The second insulating portion 142 may completely cover the first end face 1122 or may only cover a part of the first end face 1122.

[0215] In some embodiments, the first electrode tab 11 further includes a first tab 114, and the first tab 114 is connected to the first current collector body 112.

[0216] In some examples, the first current collector body 112 and the first tab 114 may be an integrally formed structure; in other examples, the first tab 114 and the first current collector body 112 may be independently formed and connected by welding or other means.

[0217] The first tab 114 may be one or more.

[0218] In some embodiments, the first tab 114 is integrally formed with the first current collector body 112. Exemplarily, the first tab 114 can be formed by a die-cutting process; during the forming process of the first electrode sheet, a part of the first electrode sheet is removed by the die-cutting process to form the first tab 114 protruding outwards.

[0219] In some embodiments, the first end face 1122 is located at one end of the first current collector body 112 along the first direction Z.

[0220] Exemplarily, after the first electrode sheet 11 is flattened, the first end face 1122 can be located at one end of the first current collector body 112 along the length direction L of the first electrode sheet 11, or can be located at one end of the first current collector body 112 along the width direction of the first electrode sheet body 111.

[0221] In some embodiments, the first current collector body 112 has two first end faces 1122 oppositely arranged along the first direction Z. An insulating member 14 is provided on at least one first end face 1122.

[0222] In some embodiments, the electrode assembly 10 is a wound structure. Optionally, the first direction Z can be parallel to the winding axis of the electrode assembly 10.

[0223] In some embodiments, the first electrode sheet 11 further includes a first tab 114, and the first tab 114 extends outwards from the first end face 1122 along the first direction Z.

[0224] Exemplarily, the first current collector body 112 has two first end faces 1122, and all the first tabs 114 extend outwards from the same first end face 1122. Alternatively, there are multiple first tabs 114, a part of the first tabs 114 extends outwards from one first end face 1122, and another part of the first tabs 114 extends outwards from the other first end face 1122.

[0225] In some embodiments, the first tab 114 extends outwards from the first end face 1122 along the first direction Z and passes through the second insulating portion 142.

[0226] The second insulating portion 142 can block the burrs formed on the first end face 1122 during the forming process of the first tab 114, thereby reducing the risk of short circuit.

[0227] In some embodiments, the first end face 1122 includes a tab lead-out area 1122a and a non-tab lead-out area 1122b, and the first tab 114 only extends out from the tab lead-out area 1122a and protrudes out of the second insulating portion 142 along the first direction Z in a direction away from the first current collector body 112.

[0228] The tab lead-out area 1122a can be one or multiple. Exemplarily, the number of tab lead-out areas 1122a corresponds to the number of first tabs 114. After the first tab 114 is removed, the tab lead-out area 1122a is exposed.

[0229] The non-tab lead-out area 1122b can be one or multiple.

[0230] In some examples, both the tab lead-out area 1122a and the non-tab lead-out area 1122b are multiple, and the multiple tab lead-out areas 1122a and the multiple non-tab lead-out areas 1122b are alternately arranged.

[0231] The first tab 114 protrudes from the second insulating portion 142 to facilitate connection with other conductive structures and reduce the risk of interference between the second insulating portion 142 and the conductive structures.

[0232] In some embodiments, the second insulating portion 142 covers at least a part of the non-tab lead-out area 1122b. The second insulating portion 142 can separate the burrs on the non-tab lead-out area 1122b from the second electrode plate, thereby reducing the short-circuit risk.

[0233] In some embodiments, the second insulating portion 142 completely covers the non-tab lead-out area 1122b. The second insulating portion 142 can completely cover the non-tab lead-out area 1122b, thereby covering the burrs of the non-tab lead-out area 1122b and reducing the short-circuit risk.

[0234] In some embodiments, the second insulating portion 142 has a channel 142a, the first tab 114 passes through the channel 142a, and the second insulating portion 142 completely covers the non-tab lead-out area 1122b.

[0235] By providing the channel 142a, the first tab 114 can be avoided, and the risk of interference between the insulating member 14 and the first tab 114 can be reduced.

[0236] In some embodiments, the second insulating portion 142 includes a first extension portion 1421 and a second extension portion 1422. The first extension portion 1421 is provided on the outer side of the non-tab lead-out area 1122b along the first direction Z, and the second extension portion 1422 is provided on the outer side of the tab lead-out area 1122a along the first direction Z and covers at least a part of the first tab along the thickness direction Y.

[0237] Exemplarily, the plane parallel to the first direction Z and passing through the junction of the non-tab lead-out area 1122b and the tab lead-out area 1122a can be the interface between the first extension portion 1421 and the second extension portion 1422.

[0238] In the first direction Z, the size of the first extension portion 1421 and the size of the second extension portion 1422 can be equal or unequal.

[0239] The second extension part 1422 can support the root of the first tab 114 near the tab lead-out area 1122a, reducing the risk that the first tab 114 is inserted upside down between the first electrode tab 11 and the second electrode tab 12 during bending, thereby reducing the short-circuit risk and improving the reliability.

[0240] Exemplarily, in the battery cell 6, in order to save the space occupied by the first tab 114, the first tab 114 can be bent; during the bending process of the first tab 114, its root may be deformed and inserted upside down between the first electrode tab 11 and the second electrode tab 12; the second extension part 1422 can support the root of the first tab 114 near the tab lead-out area 1122a, reducing the risk that the first tab 114 is inserted upside down between the first electrode tab 11 and the second electrode tab 12.

[0241] In some embodiments, the first extension part 1421 covers the non-tab lead-out area 1122b along the first direction Z to block the burrs on the non-tab lead-out area 1122b.

[0242] In some embodiments, the dimension D2 of the first extension part 1421 along the first direction Z is equal to the dimension D1 of the second extension part 1422 along the first direction Z.

[0243] The second insulating part 142 is provided with an equal width as a whole, which is easy to form.

[0244] In some embodiments, D1 is 2 mm - 10 mm.

[0245] Optionally, D1 is 2 mm, 3 mm, 4 mm, 5 mm, 6 mm, 7 mm, 8 mm, 9 mm or 10 mm.

[0246] In the embodiments of the present application, D1 is limited to be greater than or equal to 2 mm to provide effective support for the first tab 114, reducing the risk that the first tab 114 is inserted upside down between the first electrode tab 11 and the second electrode tab 12 and improving the reliability. In the embodiments of the present application, D1 is limited to be less than or equal to 10 mm to reduce the volume and weight of the insulating part 14 and improve the energy density.

[0247] In some embodiments, in the first direction Z, the dimension W3 of the root area of the first tab 114 covered by the second extension part 1422 is greater than or equal to 0.2 times the dimension W4 of the first tab 114 and less than or equal to 0.6 times the dimension W4 of the first tab 114. Exemplarily, 0.2 ≤ W3 / W4 ≤ 0.6.

[0248] Limit W3 / W4 to be greater than or equal to 0.2 to provide effective support for the first tab 114, reduce the risk of the first tab 114 being inserted upside down between the first electrode sheet 11 and the second electrode sheet 12, and improve reliability. In the embodiments of the present application, W3 / W4 is limited to be less than or equal to 0.6 to reduce the volume and weight of the insulating member 14 and improve the energy density.

[0249] In some embodiments, D1 is equal to W3.

[0250] In some embodiments, the first electrode sheet 11 and the second electrode sheet 12 are wound. Exemplarily, the electrode assembly 10 is of a wound structure.

[0251] In some embodiments, the first electrode sheet 11 includes a plurality of first tabs 114, and the plurality of first tabs 114 are spaced apart in the winding direction V of the first electrode sheet 11.

[0252] In some embodiments, the first extension portion 1421 is connected to the second extension portion 1422.

[0253] In some embodiments, the second insulating portion 142 connects adjacent first tabs 114. When the first tab 114 is bent, the roots of the adjacent first tabs 114 can limit each other's deformation through the second insulating portion 142, thereby reducing the risk of the first tab 114 being inserted upside down between the first electrode sheet 11 and the second electrode sheet 12 and improving reliability.

[0254] In some embodiments, the second insulating portion 142 connects a plurality of first tabs 114.

[0255] In some embodiments, the first insulating portion 141 is connected to the first active material layer 113, which can increase the connection area between the insulating member 14 and the first electrode sheet body 111 and reduce the risk of the insulating member 14 falling off.

[0256] The first insulating portion 141 and the first active material layer 113 may or may not overlap in the thickness direction Y.

[0257] In some embodiments, at least a partial region of the first insulating portion 141 overlaps with the first active material layer 113 in the thickness direction Y and is connected to the first active material layer 113.

[0258] The embodiments of the present application can further increase the connection area between the first insulating portion 141 and the first electrode sheet body 111.

[0259] In some embodiments, the width of the overlapping region between the first insulating portion 141 and the first active material layer 113 is W1, and W1 is 0.1 mm - 2 mm.

[0260] Optionally, W1 is 0.1 mm, 0.2 mm, 0.3 mm, 0.4 mm, 0.5 mm, 0.6 mm, 0.7 mm, 0.8 mm, 0.9 mm, 1 mm, 1.1 mm, 1.2 mm, 1.3 mm, 1.4 mm, 1.5 mm, 1.6 mm, 1.7 mm, 1.8 mm, 1.9 mm or 2 mm.

[0261] In some embodiments, the width of the region where the first insulating portion 141 overlaps with the first active material layer 113 is W1, and W1 is 0.1 mm - 1 mm.

[0262] W1 is defined to be greater than or equal to 0.1 mm to increase the connection area between the first insulating portion 141 and the first active material layer 113 and reduce the risk of the insulating member 14 falling off. W1 is defined to be less than or equal to 1 mm, which can reduce the amount of the insulating member 14 used, reduce the blocking of active ions by the first insulating portion 141, and reduce the capacity loss of the battery cell 6.

[0263] In some embodiments, the first active material layer 113 includes a main body region 1131 arranged along the first direction Z and a thinning region 1132 connected to the main body region 1131. The thinning region 1132 is located on one side of the main body region 1131 along the first direction Z close to the first end face 1122, and at least part of the thickness of the thinning region 1132 is less than the thickness of the main body region 1131. The first insulating portion 141 covers at least part of the thinning region 1132 along the thickness direction Y.

[0264] Exemplarily, one end of the thinning region 1132 close to the main body region 1131 is directly connected to the main body region 1131. In some examples, the thickness of one end of the thinning region 1132 close to the main body region 1131 is less than the thickness of one end of the main body region 1131 close to the thinning region 1132, and a step is formed at the connection between the thinning region 1132 and the main body region 1131. In other examples, the thickness of one end of the thinning region 1132 close to the main body region 1131 is less than the thickness of one end of the main body region 1131 equal to the thinning region 1132.

[0265] Exemplarily, the main body region 1131 is generally a structure with an equal thickness. The average thickness of the thinning region 1132 is less than the thickness of the main body region 1131.

[0266] During the forming process of the first pole piece 11, it is necessary to roll the first active material layer 113 to increase the compaction density of the first active material layer 113. By providing the thinning region 1132 in this application, the pressure on the edge portion of the first active material layer 113 can be reduced, and the risk of cracking of the first current collector main body 112 can be reduced. By arranging the first insulating portion 141 in the space on one side of the thinning region 1132 along the thickness direction Y, the space utilization rate can be improved.

[0267] In some embodiments, the thickness of one end of the thinning region 1132 close to the main body region 1131 is equal to the thickness of one end of the main body region 1131 close to the thinning region 1132. Along the direction away from the main body region 1131, the thickness of the thinning region 1132 gradually decreases. The thickness of the thinning region 1132 changes smoothly, thereby reducing the risk of forming steps on the first active material layer 113 and reducing stress concentration.

[0268] In some embodiments, in the first direction Z, the first insulating portion 141 is spaced apart from the main body region 1131 so that the main body region 1131 and the first insulating portion 141 do not overlap in the thickness direction Y, thereby improving space utilization.

[0269] In addition, in the thickness direction Y, the main body region 1131 and the first insulating portion 141 do not overlap, and the first insulating portion 141 is not likely to block the transmission of ions between the main body region 1131 and the second pole piece, thereby reducing the capacity loss of the battery cell.

[0270] In some embodiments, along the direction from the first current collector main body 112 to the first active material layer 113, the first insulating portion 141 does not extend beyond the surface of the main body region 1131 facing away from the first current collector main body 112.

[0271] The embodiments of the present application can reduce the space occupied by the first insulating portion 141 in the thickness direction Y, improve space utilization, and reduce the risk of the first insulating portion 141 squeezing the second pole piece 12.

[0272] In some embodiments, the thickness t1 of the end of the thinning region 1132 away from the main body region 1131 is less than or equal to 0.5 times the thickness t2 of the main body region 1131. Exemplarily, t1 / t2 ≤ 0.5. Optionally, t1 / t2 ≤ 1 / 3.

[0273] The end of the thinning region 1132 away from the main body region 1131 has a smaller thickness, which can reduce the area coated by the second insulating portion 142, reduce the stress at the connection between the first insulating portion 141 and the second insulating portion 142, and reduce the risk of cracking and falling off of the insulating member 14.

[0274] In some embodiments, the first current collector main body 112 further includes two second end faces 1123, and the two second end faces 1123 are respectively disposed at both ends of the first end face 1122, and each second end face 1123 connects the two first surfaces 1121.

[0275] Optionally, the two second end faces 1123 can be respectively located at both ends of the first current collector main body 112 along the winding direction V.

[0276] In some embodiments, the insulating member 14 further includes a third insulating portion 143. The third insulating portion 143 is connected to the first insulating portion 141 and the second insulating portion 142 and covers a part of the second end face 1123.

[0277] In the thickness direction Y, the third insulating portion 143 does not overlap with the first pole piece body 111.

[0278] Optionally, the third insulating portion 143 may include a first region and a second region arranged along the first direction Z. The first region connects the two first insulating portions 141, and the second region is located on one side of the second insulating portion 142 along the winding direction V and is connected to the second insulating portion 142. The interface between the second region and the second insulating portion 142 may be coplanar with the second end face 1123.

[0279] The third insulating portion 143 can cover the burrs on the second end face 1123, thereby reducing the risk of short circuit and improving the reliability. By providing the third insulating portion 143, the risk of exposing the first end face 1122 due to assembly errors can also be reduced.

[0280] In some embodiments, there are two third insulating portions 143.

[0281] In some embodiments, the electrode assembly 10 further includes a separator 13. The separator 13 is used to separate the first pole piece 11 from the second pole piece 12. The first pole piece 11, the separator 13, and the second pole piece 12 are wound. In the winding direction V of the first pole piece, both ends of the insulating member 14 do not extend beyond the separator 13.

[0282] Exemplarily, as Figure 4 shown, the positive direction of the winding direction V is the counterclockwise direction, and the negative direction of the winding direction V is the clockwise direction. In the positive direction of the winding direction V, the insulating member 14 does not extend beyond the tail end of the separator 13; in the negative direction of the winding direction V, the insulating member 14 does not extend beyond the head end of the separator 13.

[0283] The separator 13 can bind the insulating member 14, keep the insulating member 14 in contact with the first pole piece body 111, and reduce the risk of the insulating member 14 falling off from the first pole piece body 111.

[0284] Exemplarily, in the positive direction of the winding direction V, the tail end of the separator 13 extends beyond one third insulating portion 143 of the insulating member 14. In the negative direction of the winding direction V, the head end of the separator 13 extends beyond the other third insulating portion 143 of the insulating member 14.

[0285] The separator 13 can bind the third insulating portion 143 and reduce the risk of separation of the two insulating layers of the third insulating portion 143 under the immersion of the electrolyte.

[0286] In some embodiments, the insulating member 14 includes two independently formed insulating layers 144. The insulating layer 144 includes an insulating main body 144a and a connecting portion 144b connected to the insulating main body 144a. In the thickness direction Y, the insulating main body 144a overlaps with the first electrode tab main body 111, and the connecting portion 144b does not overlap with the first electrode tab main body 111. The insulating main bodies 144a of the two insulating layers 144 respectively form two first insulating portions 141. The connecting portions 144b of the two insulating layers 144 are stacked and connected to form a second insulating portion 142.

[0287] Optionally, the connecting portions 144b of the two insulating layers 144 also form a third insulating portion 143.

[0288] The two insulating layers 144 can be attached to the first electrode tab main body 111 from both sides, thereby forming the insulating member 14. The embodiments of the present application can simplify the assembly process.

[0289] In some embodiments, t1 / t2 ≤ 0.5. The end of the thinning region 1132 away from the main body region 1131 has a smaller thickness. When attaching the insulating layer 144, the degree of bending of the insulating layer 144 at the end of the thinning region 1132 away from the main body region 1131 is smaller, which helps to reduce the risk of generating a gap between the two insulating layers 144 and improve the connection strength between the two insulating layers 144.

[0290] In some embodiments, the thickness of the insulating layer 144 is 7μm - 30μm. Optionally, the thickness of the insulating layer 144 is 4μm, 9μm, 10μm, 11μm, 12μm, 13μm, 14μm, 15μm, 20μm, 25μm or 30μm.

[0291] Limiting the thickness of the insulating layer 144 to be greater than or equal to 7μm can reduce the risk of the insulating layer 144 being pierced by burrs and improve reliability. Limiting the thickness of the insulating layer 144 to be less than or equal to 30μm can reduce the space and weight occupied by the insulating layer 144 and reduce the loss of the energy density of the battery cell 6.

[0292] Optionally, the thickness of the insulating layer 144 is 9μm - 30μm.

[0293] In some embodiments, the insulation value of the difference between the thickness of the insulating layer 144 and the thickness of the first current collector main body 112 is not greater than 10μm.

[0294] Exemplarily, the thickness of the insulating layer 144 is t3, the thickness of the first current collector main body 112 is t4, and |t3 - t4| ≤ 10μm.

[0295] The larger t3 is, the less likely the insulating layer 144 is to be punctured by burrs; correspondingly, the larger the space and weight occupied by the insulating layer 144 are. The larger t4 is, the stronger the current-carrying capacity of the first current collecting body 112 is. However, the burrs generated by the first current collecting body 112 are more serious, and the burrs are more likely to puncture the insulating layer 144.

[0296] In the embodiment of the present application, the insulation value of the difference between the thickness of the insulating layer 144 and the thickness of the first current collecting body 112 is limited to be not greater than 10 μm. On the premise that the current-carrying of the first current collecting body 112 meets the requirements, the risk of the insulating layer 144 being punctured by burrs is reduced, and the weight and space occupied by the insulating layer 144 are reduced, thereby improving the energy density.

[0297] In some embodiments, the insulation value of the difference between the thickness of the insulating layer 144 and the thickness of the first current collecting body 112 is not greater than 5 μm, so as to further reduce the difference between the thicknesses of the insulating layer 144 and the first current collecting body 112.

[0298] In some embodiments, |t3 - t4| ≤ 1 μm, so as to further reduce the difference between the thicknesses of the insulating layer 144 and the first current collecting body 112.

[0299] In some embodiments, the first end face 1122 includes a tab lead-out area 1122a and a non-tab lead-out area 1122b. The first tab 114 only extends from the tab lead-out area 1122a and protrudes from the second insulating portion 142 in a direction away from the first current collecting body 112. The non-overlapping parts of the two connecting parts 144b and the first tab 114 are directly connected to form a first extension portion 1421, and the first extension portion 1421 covers the non-tab lead-out area 1122b along the first direction Z. The overlapping parts of the two connecting parts 144b and the first tab 114 form a second extension portion 1422 and cover at least part of the first tab along the thickness direction Y.

[0300] The first extension portion 1421 can cover the non-tab lead-out area 1122b, thereby blocking the burrs on the non-tab lead-out area 1122b and reducing the short-circuit risk.

[0301] In some embodiments, the dimension of the first extension portion 1421 along the first direction Z is equal to the dimension of the second extension portion 1422 along the first direction Z.

[0302] In some embodiments, the dimension of the overlapping part of the connecting part 144b and the first tab 114 in the first direction Z is D3, and the dimension of the non-overlapping part of the connecting part 144b and the first tab 114 protruding from the non-tab lead-out area 1122b in the first direction Z is D4, and D3 is equal to D4.

[0303] Exemplarily, D3 is equal to D1, and D4 is equal to D2.

[0304] The region where the two connecting portions 144b are directly connected has a relatively large dimension in the first direction Z, thereby improving the connection strength of the two connecting portions 144b and enhancing the reliability of the connecting portion 144b covering the non-tab lead-out region 1122b.

[0305] In some embodiments, the insulating layer 144 is rectangular in the flattened state.

[0306] In some embodiments, in the first direction Z, the width of the insulating layer 144 is 3 mm - 20 mm. Optionally, the width of the insulating layer 144 is 3 mm, 5 mm, 6 mm, 8 mm, 10 mm, 12 mm, 15 mm, 18 mm, or 20 mm.

[0307] In some embodiments, in the first direction Z, the width of the insulating layer 144 is 5 mm - 20 mm.

[0308] In some embodiments, the first current collector body 112 includes two first end faces 1122 oppositely arranged in the first direction Z, and the first direction Z is perpendicular to the thickness direction Y of the first electrode tab body 111. The electrode assembly 10 includes two insulating members 14, and the two insulating members 14 are respectively arranged outside the two first end faces 1122.

[0309] The two insulating members 14 can separate the burrs on the two first end faces 1122 from the second electrode tab, thereby further reducing the short-circuit risk.

[0310] In some embodiments, the second electrode tab 12 includes a second electrode tab body 121, and the second electrode tab body 121 is stacked with the first electrode tab body 111. The second electrode tab body 121 includes a second current collector body 122 and a second active material layer 123. The second current collector body 122 includes two second surfaces 1221 arranged oppositely and a third end face 1222 connecting the two second surfaces 1221, and the second active material layer 123 is arranged on the second surface 1221.

[0311] In some examples, the second electrode tab 12 is a positive electrode tab, the positive electrode current collector may include the second current collector body 122, and the second active material layer 123 is a positive electrode active material layer. In other examples, the second electrode tab 12 is a negative electrode tab, the negative electrode current collector includes the second current collector body 122, and the second active material layer 123 is a negative electrode active material layer.

[0312] In the embodiments of the present application, the second active material layer 123 may be provided on one of the second surfaces 1221, or may be provided on both of the second surfaces 1221.

[0313] In some embodiments, the first end face 1122 is located at one end of the first current collector body 112 along the first direction Z, and the third end face 1222 is located at one end of the second current collector body 122 along the first direction Z. In the thickness direction Y, the insulating member 14 separates the third end face 1222 from the first pole piece 11.

[0314] Exemplarily, there are two first end faces 1122 and two third end faces 1222. One insulating member 14 separates the third end face 1222 close to one first end face 1122 from the first pole piece 11, and the other insulating member 14 separates the other third end face 1222 close to the other first end face 1122 from the first pole piece 11.

[0315] In the embodiments of the present application, it may be the first insulating portion 141 that separates the third end face 1222 from the first pole piece 11, or it may be the second insulating portion 142 that separates the third end face 1222 from the first pole piece 11.

[0316] The insulating member 14 can also separate the burrs on the third end face 1222 from the first pole piece 11, thereby reducing the risk of conduction between the burrs on the third end face 1222 and the first pole piece 11, reducing the possibility of thermal runaway caused by short circuit, and improving the reliability of the battery cell 6.

[0317] In some embodiments, the first pole piece 11 is a positive electrode piece, and the second pole piece 12 is a negative electrode piece. In the first direction Z, both ends of the second active material layer 123 extend beyond the first pole piece body 111.

[0318] The insulating member 14 shields at least a part of the first end face 1122, so that even if the second active material layer 123 overlaps with the first end face 1122 in the stacking direction, it is not easy to contact the burrs on the first end face 1122. The second active material layer 123 can provide more embedding sites for the active ions released from the first active material layer 113, thereby reducing the risk of precipitation of active ions, improving the cycle performance of the battery cell 6, and enhancing the reliability.

[0319] In some embodiments, the electrode assembly 10 further includes a separator 13, and the separator 13 is used to separate the first pole piece body 111 from the second pole piece 12. In the first direction Z, the end of the second insulating portion 142 far from the first insulating portion 141 does not extend beyond the separator 13.

[0320] The embodiments of the present application can reduce the amount of the second insulating portion 142, reduce the weight and space occupied by the second insulating portion 142, and improve the energy density.

[0321] In some embodiments, the melting point of the insulating member 14 is 95°C - 150°C.

[0322] Optionally, the melting point of the insulating member 14 is 95°C, 100°C, 110°C, 120°C, 130°C, 140°C, 145°C or 150°C.

[0323] During the charge and discharge process of the battery cell 6, the first current collecting body 112 generates heat. The insulating member 14 has a relatively high melting point, which can reduce the risk of the insulating member 14 being softened or falling off due to heat, thereby improving reliability.

[0324] In some embodiments, the insulating member 14 includes a colloid, which is bonded to the first pole piece body 111. The colloid is configured to not undergo a redox reaction in a voltage range of 2.5V-4.5V. The colloid is not easily oxidized and failed in a voltage environment of 2.5V-4.5V, thereby reducing the risk of the insulating member 14 falling off and improving reliability.

[0325] As an example, the electrochemical stability of the colloid can be tested as follows:

[0326] Peeling off part of the colloid from the first electrode sheet 11;

[0327] Conductive carbon black and colloid are mixed in a mass ratio of 7:3, and then solvent N-methylpyrrolidone is added to disperse uniformly to obtain slurry, wherein the solid content of the slurry is controlled at 7%-10%;

[0328] The slurry is coated on aluminum foil and dried to obtain a pole piece;

[0329] The prepared electrode was made into a button cell for cyclic voltammetry test.

[0330] The test conditions are: scan 3 times at a scan speed of 0.1mv / s, observe whether there is a redox peak in the voltage range of 2.5V-5V, plot the current-voltage curve, and record the voltage at which the oxidation peak first appears. The voltage at which the oxidation peak first appears can be used as the voltage at which the colloid begins to undergo redox reaction.

[0331] In some embodiments, the first electrode sheet 11 is a positive electrode sheet, and the first active material layer 113 includes a positive electrode active material, and the positive electrode active material includes lithium nickel cobalt manganese oxide. Lithium nickel cobalt manganese oxide has the advantage of high operating voltage. The colloid of the embodiment of the present application is not easy to oxidize and fail at a higher operating voltage, thereby reducing the risk of the insulating member 14 falling off and improving reliability.

[0332] In some embodiments, the insulating member 14 includes a colloid including at least one of ethylene and copolymers thereof, polyolefins, polyesters, polyurethanes, polyamides, styrene and block copolymers thereof.

[0333] The colloid has a high bonding strength and is not easy to fall off from the first pole piece body 111 .

[0334] Optionally, the colloid can be a hot-melt colloid. The insulating member 14 can be a hot-melt adhesive film.

[0335] Optionally, during the production process of the first electrode sheet 11, the colloid can be directly coated on the first electrode sheet 11, and after the colloid is cured, the insulating member 14 is formed. In some embodiments, the elastic modulus of the insulating member 14 is 500 Mpa - 3000 Mpa.

[0336] In some examples, the insulating member 14 is an integral structure, and the elastic modulus of the insulating member 14 is 500 Mpa - 3000 Mpa. In other examples, the insulating member 14 includes two insulating layers 144, and the elastic modulus of the insulating member 14 refers to the elastic modulus of the insulating layer 144.

[0337] As an example, the elastic modulus of the insulating member 14 can be 500 Mpa, 600 Mpa, 700 Mpa, 770 Mpa, 800 Mpa, 900 Mpa, 1000 Mpa, 1200 Mpa, 1300 Mpa, 1320 Mpa, 1400 Mpa, 1500 Mpa, 1800 Mpa, 2000 Mpa, 2200 Mpa, 2500 Mpa, 2600 Mpa, 2800 Mpa or 3000 Mpa.

[0338] The insulating member 14 has a relatively high elastic modulus, which can provide support for the first tab 114, reduce the risk of the root of the first tab 114 being inserted between the first electrode sheet 11 and the second electrode sheet 12, and improve the reliability.

[0339] As an example, the elastic modulus of the insulating member 14 can be tested with reference to the national standard GBT 22315-2008 "Test Methods for Elastic Modulus and Poisson's Ratio of Metallic Materials".

[0340] In some embodiments, the elastic modulus of the insulating member 14 is 770 Mpa - 1320 Mpa.

[0341] In some embodiments, the tensile strength of the insulating member 14 is 949 kgf / cm 2 -1363 kgf / cm 2 . Optionally, the tensile strength of the insulating member 14 is 949 kgf / cm 2 、1000 kgf / cm 2 、1050 kgf / cm 2 、1100 kgf / cm 2 、1150 kgf / cm 2 、1200 kgf / cm 2 、1250 kgf / cm 2 、1300 kgf / cm 2 or 1363 kgf / cm 2。

[0342] The insulating member 14 has a high tensile strength and is not easily deformed when subjected to the tensile force from the first tab 114. Correspondingly, the insulating member 14 can effectively limit the deformation of the first tab 114, reduce the risk of the root of the first tab 114 being inserted upside down between the first electrode plate 11 and the second electrode plate 12, and improve the reliability.

[0343] As an example, the tensile strength of the insulating member 14 can be tested with reference to the national standard GB / T 228-2002 "Metallic materials - Tensile testing at ambient temperature".

[0344] In some embodiments, the puncture strength of the insulating member 14 is greater than or equal to 300 gf. Optionally, the puncture strength of the insulating member 14 is greater than or equal to 400 gf.

[0345] As an example, the puncture strength of the insulating member can be measured in the following manner:

[0346] Cut a section of the insulating member to prepare a sheet sample;

[0347] Fix the sample to the test fixture;

[0348] Use a 1-mm diameter puncture needle on a puncture tester and perform puncture at a speed of 50 mm / min. After the measured data is stable, the top puncture force F is obtained, and then the puncture strength (unit: gf) is calculated as F / 9.8*1000.

[0349] The embodiments of the present application can reduce the risk of the insulating member 14 being punctured by burrs, thereby reducing the risk of the burrs being electrically connected to the second electrode plate 12, reducing the possibility of thermal runaway caused by short circuit, and improving the reliability of the battery cell 6.

[0350] In some embodiments, the puncture strength of the insulating member 14 is greater than the puncture strength of the separator.

[0351] In some embodiments, the insulating member 14 is connected to the first active material layer 113. The peel strength between the insulating member 14 and the first active material layer 113 is higher than the peel strength between the first active material layer 113 and the first surface 1121.

[0352] As an example, the insulating member 14 can be fixed on a tensile testing machine and pulled at 180°. During the pulling process, the first active material layer 113 is peeled off from the first surface 1121, while the insulating member 14 remains connected to the first active material layer 113.

[0353] As an example, the peel strength can be tested with reference to "GB / T 2792-2014 Test methods for peel strength of adhesive tapes".

[0354] In the embodiments of the present application, the stripping strength between the insulating member 14 and the first active material layer 113 is relatively high, thereby reducing the risk of the insulating member 14 falling off and improving the reliability.

[0355] In some embodiments, the battery cell 6 includes an electrolyte accommodated in the housing 20. The insulating member 14 remains stable in the electrolyte.

[0356] Exemplarily, after being immersed in the electrolyte for 1000 hours, the stripping strength between the insulating member 14 and the first active material layer 113 is greater than or equal to 2 N / m. Optionally, after being immersed in the electrolyte for 1000 hours, the stripping strength between the insulating member 14 and the first active material layer 113 is 15 N / m - 200 N / m.

[0357] In some embodiments, the insulating member 14 has good insulation properties. The insulating member 14 will not break down under a voltage of 200 V, and the resistance of the insulating member 14 is greater than or equal to 9999 megaohms.

[0358] In some embodiments, the first electrode plate 11 is a positive electrode plate, the first active material layer 113 includes a positive electrode active material, and the positive electrode active material includes a lithium transition metal oxide.

[0359] The lithium transition metal oxide includes at least one of compounds with the chemical formula Li a Ni b Co c M d O e A f and its modified compounds, where 0.8 ≤ a ≤ 1.2, 0.3 ≤ b ≤ 0.96, 0 < c < 1, 0 < d < 1, 1 ≤ e ≤ 2, 0 ≤ f ≤ 1, M includes at least one of Mn, Al, Zr, Zn, Cu, Cr, Mg, Fe, V, Ti, and B, and A includes at least one of N, F, S, and Cl.

[0360] As an example, b is 0.3, 0.33, 0.35, 0.4, 0.45, 0.5, 0.6, 0.65, 0.7, 0.75, 0.8, 0.82, 0.84, 0.85, 0.88, 0.9, 0.92, 0.94, 0.95, or 0.96.

[0361] The battery cell containing the lithium transition metal oxide has advantages such as high energy density, good low-temperature performance, and good charge and discharge performance.

[0362] A higher nickel content in lithium transition metal oxides can store more electrical energy, thus significantly improving the energy density of a single battery cell. As the nickel content increases, the usage of cobalt, which is a scarce and expensive metal, relatively decreases. Reducing the use of cobalt can lower the cost of a single battery cell. A single battery cell with a higher nickel content has a higher electrical conductivity, which means the single battery cell can operate at a higher power, support fast charging and high-current discharging. In a low-temperature environment, the capacity attenuation of a single battery cell with a higher nickel content is relatively small, and it can maintain a high discharge efficiency, enabling electrical devices to be used normally in a low-temperature environment.

[0363] The working voltage of the single battery cell is high, and the lithium transition metal oxide of the single battery cell has good activity. When an internal short circuit occurs in the single battery cell, the risk of thermal runaway in the single battery cell is relatively high. The insulating member 14 in the embodiment of the present application can separate the burrs on the first end face 1122 from the second pole piece 12, thereby reducing the risk of the burrs being electrically connected to the second pole piece 12, decreasing the possibility of thermal runaway caused by short circuit, and improving the reliability of the single battery cell containing lithium transition metal oxide.

[0364] In some embodiments, 0.5 ≤ b ≤ 0.9.

[0365] In some embodiments, the first pole piece 11 is a positive pole piece, the first active material layer 113 includes a positive electrode active material, and the positive electrode active material includes lithium nickel cobalt manganese oxide.

[0366] Lithium nickel cobalt manganese oxide has the advantages of high energy density, good cycling performance, high working voltage, etc.

[0367] Lithium nickel cobalt manganese oxide helps the single battery cell to still maintain good performance after multiple cycles, reduces the rate of capacity attenuation of the single battery cell, and thus extends the service life of the single battery cell. The higher working voltage can enable the single battery cell to have a more excellent power output performance during the charge and discharge process and can adapt to devices with a variety of different voltage requirements.

[0368] In some embodiments, the lithium nickel cobalt manganese oxide is LiNi 1 / 3 Co 1 / 3 Mn 1 / 3 O2, LiNi 0.5 Co 0.2 Mn 0.3 O2, LiNi 0.5 Co 0.25 Mn 0.25 O2, LiNi 0.6 Co 0.2 Mn 0.2 O2, LiNi 0.8 Co 0.1 Mn 0.1 O2, LiNi0.9 Co 0.05 Mn 0.05 O2, LiNi 0.92 Co 0.03 Mn 0.05 O2, LiNi 0.95 Co 0.02 Mn 0.03 O2 or LiNi 0.96 Co 0.02 Mn 0.02 O2.

[0369] Figure 15 Schematic diagram of the first pole piece of the electrode assembly provided for some other embodiments of the present application in the unfolded state, where the tab lead-out area is covered by the first tab and is shown by a dashed line in Figure 15 ; Figure 16 is Figure 15 schematic diagram of the first pole piece shown in Figure 17 is Figure 16 cross-sectional schematic diagram taken along the D-D direction.

[0370] Referring to Figures 15 to 17 , in some embodiments, the first surface 1121 includes a coating area 1121a and an uncoated area 1121b arranged along the first direction Z. One end of the uncoated area 1121b is connected to the first end face 1122, and the other end is connected to the coating area 1121a. The coating area 1121a is coated with the first active material layer 113, and the uncoated area 1121b is not coated with the first active material layer 113. The first insulating portion 141 is connected to the uncoated area 1121b.

[0371] By providing the uncoated area 1121b, the connection area between the first current collector body 112 and the insulating member 14 can be increased, the risk of the insulating member 14 falling off can be reduced, and the reliability can be improved. The first end face 1122 and the first active material layer 113 are spaced apart along the first direction Z, so that during the cutting process of the first pole piece 11, the risk of cutting the first active material layer 113 can be reduced, and the waste of active material can be reduced.

[0372] In some embodiments, the first current collector body 112 includes two first end faces 1122. One end of the uncoated area 1121b away from the coating area 1121a is connected to one first end face 1122, and one end of the coating area 1121a away from the uncoated area 1121b is connected to the other first end face 1122. The first insulating portion 141 of one insulating member 14 is connected to the uncoated area 1121b, and the first insulating portion 141 of the other insulating member 14 is connected to the coating area 1121a.

[0373] In some embodiments, the first insulating portion 141 completely covers the uncoated area 1121b to reduce the possibility of electrical conduction between the uncoated area 1121b and the second pole piece 12, reduce the short-circuit risk, and improve reliability.

[0374] In some embodiments, the absolute value of the difference between the thickness of the insulating layer 144 and the thickness of the first current collector body 112 is less than or equal to 10 μm. That is, |t3 - t4| ≤ 10 μm.

[0375] When the insulating layer 144 bends at the junction of the uncoated area 1121b and the first end face 1122, the insulating layer 144 is not easily punctured by the junction of the uncoated area 1121b and the first end face 1122, and the insulating layer 144 is more likely to fit with the first end face 1122.

[0376] In the first direction Z, the size of the area where the insulating member 14 covers the uncoated area 1121b is greater than or equal to 1 mm, so as to increase the connection strength between the insulating member 14 and the uncoated area 1121b and reduce the risk of the insulating member 14 falling off from the first pole piece 11.

[0377] Exemplarily, in the first direction Z, the size of the area where the insulating member 14 covers the uncoated area 1121b is W2. Optionally, W2 is 1 mm, 1.5 mm, 2 mm, 2.5 mm, 3 mm, 3.5 mm, 4 mm, 4.5 mm or 5 mm.

[0378] In some embodiments, W2 is less than or equal to 5 mm. Limiting W2 to be less than or equal to 5 mm can reduce the space and weight occupied by the insulating member 14, reduce the requirements for the size of the uncoated area 1121b, increase the area of the coated area 1121a, and improve the energy density of the battery cell 6.

[0379] In some embodiments, the first pole piece 11 further includes a first tab 114. The first tab 114 extends outward from the first end face 1122 along the first direction Z and passes through the second insulating portion 142.

[0380] In some embodiments, the first current collector body 112 has two first end faces 1122. The first tab 114 extends from one of the first end faces 1122. The electrode assembly 10 includes two insulating members 14, and the two insulating members 14 respectively cover the two first end faces 1122.

[0381] Exemplarily, for the insulating member 14 attached to the first end face 1122 from which the first tab 114 extends, the size of the area where the insulating member 14 overlaps with the first active material layer 113 along the first direction Z is 0.5 mm, the size of the area where the insulating member 14 overlaps with the uncoated area 1121b along the first direction Z is 3 mm, and the size of the second insulating portion 142 along the first direction Z is 4.5 mm.

[0382] For the insulating member 14 attached to the first end face 1122 where the first tab 114 is not led out, the dimension of the area where the insulating member 14 overlaps with the first active material layer 113 in the first direction Z is 0.5 mm, and the dimension of the second insulating portion 142 in the first direction Z is 1.5 mm.

[0383] Figure 18 It is a schematic diagram of the insulating member provided in some embodiments of the present application before being assembled to the first electrode tab.

[0384] Refer to Figure 18 , in some embodiments, the insulating member 14 is an integrally formed structure, which can enhance the connection stability between the insulating member 14 and the first electrode tab body 111.

[0385] In some embodiments, the insulating member 14 is provided with a channel 142a for the first tab 114 to pass through.

[0386] Exemplarily, before assembling the first electrode tab 11 and the insulating member 14, the insulating member 14 can be in a flat plate structure. The first tab 114 can be aligned with the channel 142a of the insulating member 14 first, and the first tab 114 can be made to pass through the channel 142a. After the insulating member 14 abuts against the first end face 1122, the insulating member 14 can be folded over to attach the insulating member 14 to the first electrode tab body 111.

[0387] Figure 19 It is a schematic diagram of the first electrode tab and the insulating member of the electrode assembly provided in some other embodiments of the present application in an unfolded state, where the part of the first electrode tab covered by the insulating member is shown by a dashed line; Figure 20 For Figure 19 the enlarged schematic diagram at the circular frame.

[0388] Refer to Figure 19 and Figure 20 , in some embodiments, the first extension portion 1421 is provided with a first part 1421a and a second part 1421b. The second part 1421b is connected to the second extension portion 1422. The dimension of the second part 1421b in the first direction Z is equal to the dimension of the second extension portion 1422 in the first direction Z. The first part 1421a is configured to be formed by setting a recess 147 on the second insulating portion 142. The dimension of the first part 1421a in the first direction Z is smaller than the dimension of the second extension portion 1422 in the first direction Z.

[0389] By setting the recess 147, the dimension of the first part 1421a in the first direction Z can be reduced, thereby saving the amount of the insulating member 14 used and improving the energy density of the battery cell.

[0390] Figure 21 It is a schematic diagram of the structure of the insulating member of the electrode assembly provided in some embodiments of the present application.

[0391] Reference Figure 21 In some embodiments, the insulating member 14 includes a substrate layer 145 and an adhesive layer 146 , and the substrate layer 145 is connected to the first pole piece body 111 through the adhesive layer 146 .

[0392] The substrate layer 145 can improve the strength of the insulating member 14 and reduce deformation of the insulating member 14 during attachment. The adhesive layer 146 can bond the substrate layer 145 to the first pole piece body 111 to reduce the risk of the substrate layer 145 falling off from the first pole piece body 111.

[0393] In some embodiments, the glue layer 146 is configured to not undergo a redox reaction in a voltage range of 2.5V-4.5V. The glue layer 146 is configured to not undergo a redox reaction in a voltage range of 2.5V-4.5V. The colloid is not easily oxidized and failed in a voltage environment of 2.5V-4.5V, thereby reducing the risk of the insulating member 14 falling off and improving reliability.

[0394] As an example, the electrochemical stability of the glue layer 146 can be tested as follows:

[0395] Peel off the insulating member from the first pole piece 11 and scrape off part of the glue layer;

[0396] After the conductive carbon black and the adhesive layer are mixed in a mass ratio of 7:3, a solvent N-methylpyrrolidone is added and dispersed evenly to obtain a slurry, and the solid content of the slurry is controlled at 7%-10%;

[0397] The slurry is coated on aluminum foil and dried to obtain a pole piece;

[0398] The prepared electrode was made into a button cell for cyclic voltammetry test.

[0399] The test conditions are: scan 3 times at a scan speed of 0.1mv / s, observe whether there is a redox peak in the voltage range of 2.5V-5V, plot the current-voltage curve, and record the voltage at which the oxidation peak first appears. The voltage at which the oxidation peak first appears can be used as the voltage at which the colloid begins to undergo redox reaction.

[0400] In some embodiments, the first electrode sheet 11 is a positive electrode sheet, and the first active material layer 113 includes a positive electrode active material, and the positive electrode active material includes lithium nickel cobalt manganese oxide. Lithium nickel cobalt manganese oxide has the advantage of high operating voltage. The colloid of the embodiment of the present application is not easy to oxidize and fail at a higher operating voltage, thereby reducing the risk of the insulating member 14 falling off and improving reliability.

[0401] In some embodiments, the substrate layer 145 includes at least one of polyethylene terephthalate (PET), polypropylene, polyethylene, and block copolymers thereof.

[0402] In some embodiments, the adhesive layer 146 includes at least one of polyolefin, polyester, styrene-isobutene copolymer, polyacrylate, styrene-butadiene rubber, or butyl rubber.

[0403] Optionally, the polyolefin includes polyisobutene.

[0404] In some embodiments, the insulating member 14 includes two insulating layers 144, and each insulating layer 144 includes a substrate layer 145 and an adhesive layer 146. The adhesive layers 146 of the two insulating layers 144 are bonded. Optionally, the insulating layer 144 is a pressure-sensitive tape.

[0405] In some embodiments, the elastic modulus of the substrate layer 145 is greater than the elastic modulus of the adhesive layer 146.

[0406] Figure 22 A partial cross-sectional schematic view of the electrode assembly provided in some other embodiments of the present application.

[0407] Referring to Figure 22 , in some embodiments, the insulating member 14 is also coated on the third end face 1222 of the second electrode tab 12. Exemplarily, the insulating member 14 coating the third end face 1222 may have a similar structure to the insulating member 14 coating the first end face 1122.

[0408] In some embodiments, the second electrode tab 12 includes a second tab 124 extending from one of the third end faces 1222.

[0409] In some embodiments, the electrode assembly 10 includes two insulating members 14 respectively attached to the two third end faces 1222.

[0410] Exemplarily, for the insulating member 14 attached to the third end face 1222 from which the second tab 124 extends, the total dimension of the insulating member 14 in the first direction Z is 5 mm, and the dimension of the region where the insulating member 14 overlaps with the second active material layer 123 in the first direction Z is 0.5 mm.

[0411] For the insulating member 14 attached to the third end face 1222 where the second tab 124 does not extend, the total dimension of the insulating member 14 in the first direction Z is 2 mm, and the dimension of the region where the insulating member 14 overlaps with the second active material layer 123 in the first direction Z is 0.5 mm.

[0412] Figure 23 A top view schematic of the electrode assembly provided in some other embodiments of the present application; Figure 24 For Figure 23 A cross-sectional schematic taken along the F-F direction.

[0413] Referring to Figure 23 and Figure 24, in some embodiments, the electrode assembly 10 further includes a separator 13 for separating the first electrode tab 11 from the second electrode tab 12. In the first direction Z, the end of the second insulating portion 142 away from the first insulating portion 141 extends beyond the separator 13.

[0414] The second insulating portion 142 protrudes from the separator 13. When the first tab 114 is bent, the second insulating portion 142 can limit the first tab 114, reduce the risk of the first tab 114 squeezing the separator 13, relieve the wrinkles of the separator 13, reduce the risk of the separator 13 shrinking inward, and improve reliability.

[0415] In some embodiments, one end of the first current collector body 112 in the first direction Z extends beyond the second electrode tab body 121.

[0416] Figure 25 A cross-sectional view of the first electrode tab and the insulating member of the electrode assembly provided in some other embodiments of the present application.

[0417] Refer to Figure 25 , in some embodiments, the first insulating portion 141 covers a part of the main body region 1131. The first insulating portion 141 is connected to both the main body region 1131 and the thinning region 1132 at the same time, which can increase the connection area between the insulating member 14 and the first electrode tab main body 111 and reduce the risk of the insulating member 14 falling off.

[0418] Figure 26 A schematic diagram of the electrode assembly provided in some other embodiments of the present application. In Figure 26 , the first electrode tab main body 111 is shown by a dotted line.

[0419] Refer to Figure 26 , in some embodiments, the first electrode tab main body 111 is flat. In the second direction X perpendicular to the first direction Z and the thickness direction Y, the two ends of the insulating member 14 do not extend beyond the separator 13.

[0420] Optionally, the second direction X may be the width direction of the first electrode tab main body 111, and the first direction Z is the length direction of the first electrode tab main body 111.

[0421] Optionally, the electrode assembly 10 is a stacked structure. The electrode assembly 10 includes a plurality of first electrode tabs 11 stacked on top of each other. An insulating member 14 is provided on each first electrode tab 11.

[0422] The second electrode tab 12 can be one or multiple. For example, the second electrode tab 12 is folded to form a plurality of stacked folding segments, and a first electrode tab 11 is clamped between adjacent folding segments.

[0423] The spacer 13 can hold the insulating member 14 in place, maintaining the contact between the insulating member 14 and the first electrode tab body 111, and reducing the risk of the insulating member 14 detaching from the first electrode tab body 111.

[0424] Figure 27 Schematic diagram of the first electrode tab and the insulating member of the electrode assembly provided in some other embodiments of the present application in the unfolded state.

[0425] Referring to Figure 27 , in some embodiments, the second insulating portion 142 is only provided on the outer side of the non-tab lead-out area 1122b along the first direction Z. The embodiments of the present application can reduce the amount of the insulating member 14 used.

[0426] Exemplarily, there are multiple second insulating portions 142, and the multiple second insulating portions 142 are arranged at intervals, and each second insulating portion 142 covers one non-tab lead-out area 1122b.

[0427] Figure 28 Schematic diagram of the first electrode tab of the electrode assembly provided in some other embodiments of the present application in the unfolded state; Figure 29 For Figure 28 Schematic diagram of the first electrode tab shown in after being connected to the insulating member, wherein the portion of the first electrode tab covered by the insulating member is shown by a dashed line; Figure 30 For Figure 29 Cross-sectional schematic diagram taken along the G-G direction.

[0428] Referring to Figures 28 to 30 , in some embodiments, the electrode assembly 10 further includes an insulating coating 115, and at least a part of the insulating coating 115 is provided between the uncoated area 1121b and the first insulating portion 141.

[0429] The insulating coating 115 can completely cover the uncoated area 1121b, or can only cover a part of the uncoated area 1121b.

[0430] In the embodiments of the present application, the insulating coating 115 and the insulating member 14 can achieve a double-layer insulation effect, thereby reducing the risk of short circuit.

[0431] In some embodiments, the insulating coating 115 is coated on the uncoated area 1121b.

[0432] In some embodiments, the insulating coating 115 includes ceramic particles.

[0433] In some embodiments, the insulating coating 115 is connected to the first active material layer.

[0434] In some embodiments, in the direction from the coated area 1121a to the uncoated area 1121b, the uncoated area 1121b protrudes from the insulating coating 115, and a part of the insulating member 14 is attached to the area of the uncoated 1121b that is not covered by the insulating coating 115.

[0435] Figure 31 A cross-sectional schematic view of a battery cell provided by some embodiments of the present application; Figure 32 is Figure 31 An enlarged schematic view at the circular frame.

[0436] According to some embodiments of the present application, the present application further provides a battery cell 6, which includes a housing 20 and the electrode assembly 10 of any of the above embodiments, and the electrode assembly 10 is accommodated in the housing 20.

[0437] Referring to Figure 3 、 Figure 23 、 Figure 24 、 Figure 31 and Figure 32 , in some embodiments, the housing 20 includes a wall portion 20a, and the wall portion 20a is located on one side of the electrode assembly 10 along the first direction Z.

[0438] The battery cell 6 further includes an insulating member 40, and the insulating member 40 is disposed on the side of the wall portion 20a facing the electrode assembly 10 and fixed to the wall portion 20a. A first end face 1122 is provided on the side of the first current collector body 112 facing the wall portion 20a. Along the direction from the electrode assembly 10 to the wall portion 20a, the insulating member 14 protrudes from the first end face 1122. In the first direction Z, the insulating member 40 abuts against the insulating member 14.

[0439] The wall portion 20a may be an end cap 22 or a wall of the housing 21.

[0440] When the battery cell 6 is subjected to an external impact, the insulating member 40 can limit the vibration amplitude of the first electrode tab 11 in the first direction Z through the insulating member 14, reduce the damage of the first electrode tab 11, and improve the reliability of the battery cell 6.

[0441] In some embodiments, the material of the insulating member 40 is plastic.

[0442] In some embodiments, the end cap 22 is the wall portion 20a.

[0443] In some embodiments, along the direction from the electrode assembly 10 to the wall portion 20a, the insulating member 14 protrudes from the separator 13. The insulating member 14 can reduce the pressure exerted by the insulating member 40 on the separator 14, relieve the wrinkles of the separator 13, reduce the risk of inward contraction of the separator 13, and improve the reliability.

[0444] In some embodiments, the insulating member 14 is wound into multiple turns along the winding direction V. The insulating member 14 can form a relatively flat support surface at one end facing the wall portion 20a, thereby increasing the contact area between the insulating member 14 and the insulating component 40 and reducing the risk of bending and wrinkling of the insulating member 14.

[0445] According to some embodiments of the present application, the present application also provides a battery, including a plurality of battery cells of any one of the above embodiments.

[0446] According to some embodiments of the present application, the present application also provides an electrical device, including a battery cell of any one of the above embodiments, and the battery cell is used to provide electrical energy for the electrical device. The electrical device can be any of the foregoing devices or systems using the battery cell.

[0447] According to some embodiments of the present application, referring to Figures 4 to 14 , an electrode assembly 10 is provided in an embodiment of the present application, including a first electrode tab 11, a second electrode tab 12, a separator 13, and an insulating member 14. The first electrode tab 11 and the second electrode tab 12 have opposite polarities, and the first electrode tab 11, the second electrode tab 12, and the separator 13 are wound along the winding direction V to form a wound structure.

[0448] The first electrode tab 11 includes a first electrode tab main body 111 and a first tab 114. The first electrode tab main body 111 includes a first current collector main body 112 and a first active material layer 113. The first current collector main body 112 includes two first surfaces 1121, two first end faces 1122, and two second end faces 1123. The two first surfaces 1121 are disposed opposite to each other along the thickness direction Y of the first electrode tab main body 111. The two first end faces 1122 are respectively located at both ends of the first current collector main body 112 along the first direction Z. The two second surfaces 1221 are respectively located at both ends of the first current collector main body 112 along the winding direction V. The first direction Z is perpendicular to the winding direction V, and the first direction Z is perpendicular to the thickness direction Y. Each first end face 1122 connects the two first surfaces 1121, and each second end face 1123 connects the two first surfaces 1121.

[0449] The first surface 1121 includes a coated area 1121a and an uncoated area 1121b arranged along the first direction Z. The first active material layer 113 is disposed in the coated area 1121a, and the first active material layer 113 is not provided in the uncoated area 1121b. One end of the uncoated area 1121b away from the coated area 1121a is connected to one first end face 1122, and one end of the coated area 1121a away from the uncoated area 1121b is connected to the other first end face 1122.

[0450] A plurality of first tab ears 114 extend from the same first end face 1122 and are connected to the uncoated area 1121b, and the plurality of first tab ears 114 are arranged at intervals along the winding direction V. The plurality of first tab ears 114 are integrally formed with the first current collecting body 112.

[0451] An insulating member 14 is used to cover the first end face 1122 from which the first tab ear 114 is led out. Specifically, an insulating member 14 is connected to the first active material layer 113 and covers the uncoated area 1121b, the first end face 1122, and the end of the second end face 1123 close to the first end face 1122. The first tab ear 114 passes through the insulating member 14.

[0452] Another insulating member 14 is used to cover the first end face 1122 from which the first tab ear 114 is not led out. Specifically, another insulating member 14 is connected to the first active material layer 113 and covers the first end face 1122 and the end of the second end face 1123 close to the first end face 1122.

[0453] The insulating member 14 includes two insulating layers 144, and the two insulating layers 144 are attached to the first electrode tab 11 from both sides to form the insulating member 14. The insulating layer 144 can be a hot melt adhesive film or a pressure-sensitive adhesive tape.

[0454] It should be noted that, without conflict, the embodiments in the present application and the features in the embodiments can be combined with each other.

[0455] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present application, rather than to limit them; although the present application has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that they can still modify the technical solutions recorded in the foregoing embodiments, or perform equivalent replacements for some of the technical features, but these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the spirit and scope of the technical solutions of the embodiments of the present application.

Claims

1. An electrode assembly, comprising a first electrode tab and a second electrode tab with opposite polarities; The first electrode tab includes a first electrode tab body, the first electrode tab body includes a first current collector body and a first active material layer, the first current collector body includes two first surfaces oppositely arranged along its own thickness direction and a first end face connecting the two first surfaces, and the first active material layer is disposed on the first surface; The electrode assembly further includes an insulating member connected to the first electrode tab body, at least a part of the insulating member is disposed outside the first end face along a first direction, and the first direction is perpendicular to the thickness direction.

2. The electrode assembly according to claim 1, wherein, The insulating member includes two first insulating parts and a second insulating part; The two first insulating parts are respectively located on both sides of the first electrode tab body along the thickness direction and are connected to the first electrode tab body; The second insulating part connects the two first insulating parts and is disposed outside the first end face along the first direction.

3. The electrode assembly according to claim 2, wherein The second insulating part covers at least a part of the first end face.

4. The electrode assembly according to claim 2 or 3, wherein, The first electrode tab further includes a first tab connected to the first current collector body, the first end face includes a tab lead-out area and a non-tab lead-out area, the first tab is only led out from the tab lead-out area, and protrudes from the second insulating part in the first direction away from the first current collector body.

5. The electrode assembly according to claim 4, wherein, The second insulating part covers at least a part of the non-tab lead-out area.

6. The electrode assembly according to claim 5, wherein, The second insulating part is only disposed outside the non-tab lead-out area along the first direction.

7. The electrode assembly according to claim 5, wherein, The second insulating part includes a first extension part and a second extension part, the first extension part is disposed outside the non-tab lead-out area along the first direction, the second extension part is disposed outside the tab lead-out area along the first direction, and covers at least a part of the tab along the thickness direction.

8. The electrode assembly according to claim 7, wherein, The first extension part covers the non-tab lead-out area along the first direction.

9. The electrode assembly according to claim 8, wherein, The dimension of the first extension part along the first direction is equal to the dimension of the second extension part along the first direction.

10. The electrode assembly according to claim 8, wherein, The first extension part is provided with a first part and a second part, the second part is connected to the second extension part, the dimension of the second part along the first direction is equal to the dimension of the second extension part along the first direction, the first part is configured to form a concave part on the second insulating part, and the dimension of the first part along the first direction is smaller than the dimension of the second extension part along the first direction.

11. The electrode assembly according to any one of claims 7-10, wherein, In the first direction, the dimension of the root area of the first tab covered by the second extension part is greater than or equal to 0.2 times the dimension of the first tab and less than or equal to 0.6 times the dimension of the first tab.

12. The electrode assembly according to any one of claims 2-11, wherein, The first insulating part is connected to the first active material layer.

13. The electrode assembly according to claim 12, wherein, At least a part of the first insulating part overlaps with the first active material layer in the thickness direction and is connected to the first active material layer.

14. The electrode assembly according to claim 12 or 13, wherein, The first active material layer includes a main body region disposed along the first direction and a thinning region connected to the main body region. The thinning region is located on a side of the main body region closer to the first end face along the first direction, and at least part of the thickness of the thinning region is less than the thickness of the main body region; The first insulating portion covers at least part of the thinning region along the thickness direction.

15. The electrode assembly according to claim 14, wherein, In the direction from the first current collector body to the first active material layer, the first insulating portion does not extend beyond the surface of the main body region facing away from the first current collector body.

16. The electrode assembly according to claim 14 or 15, wherein, In the first direction, the first insulating portion is spaced apart from the main body region.

17. The electrode assembly according to claim 14, wherein, The first insulating portion covers a part of the main body region.

18. The electrode assembly according to any one of claims 14-17, wherein, The thickness t1 of the end of the thinning region away from the main body region is less than or equal to 0.5 times the thickness t2 of the main body region.

19. The electrode assembly according to any one of claims 2-18, wherein, The first surface includes a coating region and an uncoated region disposed along the first direction. One end of the uncoated region is connected to the first end face, and the other end is connected to the coating region. The coating region is coated with the first active material layer, and the uncoated region is not coated with the first active material layer; The first insulating portion is connected to the uncoated region.

20. The electrode assembly according to claim 19, wherein, The first insulating portion completely covers the uncoated region.

21. The electrode assembly according to claim 19 or 20, wherein In the first direction, the size of the region where the insulating member covers the uncoated region is greater than or equal to 1 mm.

22. The electrode assembly according to any one of claims 19-21, wherein, The first electrode tab further includes a first tab, which extends outward from the first end face along the first direction and passes through the second insulating portion.

23. The electrode assembly according to any one of claims 19-22, wherein, The first electrode tab body further includes an insulating coating, and at least part of the insulating coating is disposed between the uncoated region and the first insulating portion.

24. The electrode assembly according to any one of claims 2-23, wherein, The insulating member includes two independently formed insulating layers. The insulating layer includes an insulating main body and a connecting portion connected to the insulating main body; in the thickness direction, the insulating main body overlaps with the first electrode tab body, and the connecting portion does not overlap with the first electrode tab body; The insulating main bodies of the two insulating layers respectively form the two first insulating portions; the connecting portions of the two insulating layers are stacked and connected to form the second insulating portion.

25. The electrode assembly according to claim 24, wherein, The thickness of the insulating layer is 7 μm - 30 μm.

26. The electrode assembly according to claim 24 or 25, wherein, The insulation value of the difference between the thickness of the insulating layer and the thickness of the first current collector body is not greater than 10 μm, optionally, not greater than 5 μm.

27. The electrode assembly according to any one of claims 24-26, wherein, The first electrode tab further includes a first tab connected to the first current collector body. The first end face includes a tab lead-out region and a non-tab lead-out region. The first tab extends only from the tab lead-out region and protrudes from the second insulating portion in a direction away from the first current collector body; The non-overlapping parts of the two connecting portions and the first tab are directly connected to form a first extension portion, and the first extension portion covers the non-tab lead-out region along the first direction; The overlapping parts of the two connecting portions and the first tab form a second extension portion and cover at least part of the first tab along the thickness direction.

28. The electrode assembly according to claim 27, wherein, The size of the first extension portion along the first direction is equal to the size of the second extension portion along the first direction.

29. The electrode assembly according to any one of claims 2-23, wherein, The insulating member is of an integrally formed structure.

30. The electrode assembly according to any one of claims 2-29, wherein, The first current collecting body further includes two second end faces, the two second end faces are respectively arranged at two ends of the first end face, and each second end face connects the two first surfaces; The insulating member further includes a third insulating portion, and the third insulating portion is connected to the first insulating portion and the second insulating portion and covers a part of the second end face.

31. The electrode assembly according to any one of claims 2-30, wherein, The first current collecting body includes two first end faces oppositely arranged in a first direction, and the first direction is perpendicular to the thickness direction of the first electrode tab body; The electrode assembly includes two insulating members, and the two insulating members are respectively arranged outside the two first end faces.

32. The electrode assembly according to any one of claims 2-31 further includes a separator for separating the first electrode tab from the second electrode tab; In the first direction, the end of the second insulating portion away from the first insulating portion extends beyond the separator.

33. The electrode assembly according to any one of claims 2-31 further includes a separator for separating the first electrode tab from the second electrode tab; In the first direction, the end of the second insulating portion away from the first insulating portion does not extend beyond the separator.

34. The electrode assembly according to any one of claims 1-33, wherein, The second electrode tab includes a second electrode tab body, and the second electrode tab body is stacked with the first electrode tab body; The second electrode tab body includes a second current collecting body and a second active material layer, the second current collecting body includes two relatively arranged second surfaces and a third end face connecting the two second surfaces, and the second active material layer is arranged on the second surfaces; The first end face is located at one end of the first current collecting body in the first direction, and the third end face is located at one end of the second current collecting body in the first direction; In the thickness direction, the insulating member separates the third end face from the first electrode tab.

35. The electrode assembly according to claim 34, wherein, The first electrode tab is a positive electrode tab, and the second electrode tab is a negative electrode tab; In the first direction, both ends of the second active material layer extend beyond the first electrode tab body.

36. The electrode assembly according to any one of claims 1-35, wherein, The melting point of the insulating member is 95°C - 150°C.

37. The electrode assembly according to any one of claims 1-36, wherein, The insulating member includes a colloid, and the colloid includes at least one of ethylene and its copolymers, polyolefins, polyesters, polyurethanes, polyamides, styrene and its block copolymers.

38. The electrode assembly according to any one of claims 1-37, wherein, The insulating member includes a colloid, and the colloid is bonded to the first electrode tab body; The colloid is configured not to undergo a redox reaction in a voltage range of 2.5V - 4.5V.

39. The electrode assembly according to any one of claims 1-36, wherein, The insulating member includes a base material layer and an adhesive layer, and the base material layer is connected to the first electrode tab body through the adhesive layer.

40. The electrode assembly according to claim 39, wherein, The adhesive layer is configured not to undergo a redox reaction in a voltage range of 2.5V - 4.5V.

41. The electrode assembly according to claim 39 or 40, wherein, The base material layer includes at least one of polyethylene terephthalate, polypropylene, polyethylene and its block copolymers; The adhesive layer includes at least one of polyolefins, polyesters, styrene-isobutene copolymers, polyacrylates, styrene-butadiene rubber or butyl rubber.

42. The electrode assembly according to any one of claims 1-41, wherein, The elastic modulus of the insulating member is 500 Mpa - 3000 Mpa. Optionally, the elastic modulus of the insulating member is 770 Mpa - 1320 Mpa.

43. The electrode assembly according to any one of claims 1-42, wherein, The tensile strength of the insulating part is 949 kgf / cm 2 -1363 kgf / cm 2 .

44. The electrode assembly according to any one of claims 1-43, wherein, The insulating member is connected to the first active material layer; The peeling strength between the insulating member and the first active material layer is higher than the peeling strength between the first active material layer and the first surface.

45. The electrode assembly according to any one of claims 1 - 44 further includes a separator for separating the first electrode tab from the second electrode tab; The first electrode tab, the separator, and the second electrode tab are wound. In the winding direction of the first electrode tab, both ends of the insulating member do not extend beyond the separator; or, the main body of the first electrode tab is flat, and in a second direction perpendicular to the first direction and the thickness direction, both ends of the insulating member do not extend beyond the separator.

46. The electrode assembly according to any one of claims 1-45, wherein, The first electrode tab is a positive electrode tab, the first active material layer includes a positive electrode active material, and the positive electrode active material includes a lithium transition metal oxide; The lithium transition metal oxide includes at least one of compounds with the chemical formula Li a Ni b Co c M d O e A f and its modified compounds, where 0.8 ≤ a ≤ 1.2, 0.3 ≤ b ≤ 0.96, 0 < c < 1, 0 < d < 1, 1 ≤ e ≤ 2, 0 ≤ f ≤ 1, M includes at least one of Mn, Al, Zr, Zn, Cu, Cr, Mg, Fe, V, Ti, and B, and A includes at least one of N, F, S, and Cl.

47. The electrode assembly according to claim 46, wherein, 0.5≤b≤0.9。 48. The electrode assembly according to any one of claims 1-47, wherein, The first electrode tab is a positive electrode tab, the first active material layer includes a positive electrode active material, and the positive electrode active material includes a lithium nickel cobalt manganese oxide.

49. The electrode assembly according to any one of claims 1 to 48, wherein, The lithium nickel cobalt manganese oxide is LiNi 1 / 3Co 1 / 3 Mn 1 / 3 O2, LiNi 0.5 Co 0.2 Mn 0.3 O2, LiNi 0.5 Co 0.25 Mn 0.25 O2, LiNi 0.6 Co 0.2 Mn 0.2 O2, LiNi 0.8 Co 0.1 Mn 0.1 O2, LiNi 0.9 Co 0.05 Mn 0.05 O2, LiNi 0.92 Co 0.03 Mn 0.05 O2, LiNi 0.95 Co 0.02 Mn 0.03 O2 or LiNi 0.96 Co 0.02 Mn 0.02 O2.

50. The electrode assembly according to any one of claims 1-49, wherein, The puncture strength of the insulating member is greater than or equal to 300 gf.

51. A battery cell includes: A housing; The electrode assembly according to any one of claims 1 - 50 is accommodated in the housing.

52. The battery cell according to claim 51, wherein, The housing includes a wall portion located on one side of the electrode assembly along the first direction; The battery cell further includes an insulating member disposed on the side of the wall portion facing the electrode assembly and fixed to the wall portion; The first current collector main body is provided with the first end face on the side facing the wall portion. Along the direction from the electrode assembly to the wall portion, the insulating member protrudes from the first end face; In the first direction, the insulating member abuts against the insulating member.

53. A battery includes a plurality of battery cells according to claim 51 or 52.

54. An electrical device includes the battery according to claim 53, and the battery is used to provide electrical energy.

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