Battery monomer, battery and electric equipment

Abstract

The utility model provides a battery monomer, a battery and electric equipment. The battery cell includes a housing having a first wall portion, an electrode assembly housed within the housing, a first insulator, and a second insulator. The electrode assembly comprises a first electrode leading-out part and a main body part. The first electrode leading-out part is arranged at one end, facing the first wall part in the first direction, of the main body part. In the first direction, the first insulating part is arranged on the surface, facing the electrode assembly, of the first wall part, and the first insulating part is used for insulating and isolating the first electrode leading-out part and the first wall part. In the first direction, at least a portion of the second insulator is disposed between the first electrode lead-out portion and the first wall portion. The material damage temperature of the second insulating part is higher than that of the first insulating part, and the second insulating part can insulate and isolate the first electrode leading-out part and the first wall part when the first insulating part is melted. And after the first insulating part is melted, the second insulating part can also play a role in insulation and isolation, thereby reducing the risk of short circuit and improving the reliability of the battery.

Description

Technical Field

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

[0002] Batteries are widely used in the field of new energy, such as electric vehicles and new energy vehicles. New energy vehicles and electric vehicles have become a new trend in the development of the automotive industry. The development of battery technology must consider many design factors at the same time, such as battery life, energy density, discharge capacity, charge and discharge rate and other performance parameters. In addition, the reliability of the battery must also be considered. However, the reliability of current batteries is poor. Utility Model Content

[0003] The purpose of the embodiments of the present application is to provide a battery cell, a battery and an electrical device, which are intended to improve the problem of poor reliability of batteries in related technologies.

[0004] In a first aspect, an embodiment of the present application provides a battery cell, comprising a shell, an electrode assembly, a first insulating member and a second insulating member, the shell having a first wall portion; the electrode assembly is accommodated in the shell, the electrode assembly comprising a first electrode lead-out portion and a main body portion, the first electrode lead-out portion being arranged at one end of the main body portion facing the first wall portion along a first direction; along the first direction, the first insulating member is arranged on a surface of the first wall portion facing the electrode assembly, the first insulating member being used to insulate and isolate the first electrode lead-out portion and the first wall portion; along the first direction, at least a portion of the second insulating member is arranged between the first electrode lead-out portion and the first wall portion, the material damage temperature of the second insulating member is greater than the material damage temperature of the first insulating member, and the second insulating member is configured to insulate and isolate the first electrode lead-out portion and the first wall portion when the first insulating member melts.

[0005] In the above technical solution, the battery cell is provided with a first insulating member and a second insulating member. In normal use, the first insulating member and the second insulating member can both insulate and isolate the first electrode lead-out portion and the first wall portion, reducing the risk of the first electrode lead-out portion contacting the first wall portion and causing a short circuit. Since the material damage temperature of the second insulating member is greater than the material damage temperature of the first insulating member, when another battery cell adjacent to the battery cell experiences thermal runaway, causing the first insulating member of the battery cell to melt, the second insulating member can still play a role in insulating and isolating the first electrode lead-out portion and the first wall portion to a certain extent, reducing the risk of the first electrode lead-out portion contacting the first wall portion and causing a short circuit. In this way, even if another battery cell adjacent to the battery cell experiences thermal runaway, it is not easy to cause the battery cell to short-circuit and continue to cause thermal runaway, which is conducive to limiting heat diffusion and improving the reliability of the battery cell.

[0006] As an optional technical solution of an embodiment of the present application, the second insulating member is connected to the first electrode lead-out portion.

[0007] In the above technical solution, by connecting the second insulating member to the first electrode lead-out portion, on the one hand, since the first insulating member is arranged on the surface of the first wall portion facing the electrode assembly, it is more convenient to connect the second insulating member to the first electrode lead-out portion, and it is not easy to interfere with the first insulating member. On the other hand, connecting the second insulating member to the first electrode lead-out portion limits the relative position of the second insulating member and the first electrode lead-out portion, so that the second insulating member can be stably located between the first electrode lead-out portion and the first wall portion, thereby insulating and isolating the first electrode lead-out portion and the first wall portion.

[0008] As an optional technical solution of an embodiment of the present application, the battery cell includes a first electrode terminal, which is arranged on the first wall portion; the first electrode lead-out portion includes a first pole ear and a first current collecting member, the first pole ear is connected to one end of the main body facing the first wall portion along a first direction, and the first current collecting member connects the first electrode terminal and the first pole ear; wherein the second insulating member is connected to the first current collecting member, and along the first direction, the second insulating member is at least partially located between the first current collecting member and the first wall portion.

[0009] In the above technical solution, the first electrode tab is connected to the first electrode terminal through the first current collecting member. There is a risk that the first current collecting member may contact the first wall portion and cause a short circuit. Therefore, the second insulating member is connected to the first current collecting member, and the second insulating member is at least partially located between the first current collecting member and the first wall portion to insulate and isolate the first current collecting member from the first wall portion, thereby reducing the risk of short circuit in the battery cell and improving the reliability of the battery cell.

[0010] As an optional technical solution of an embodiment of the present application, the first current collecting component includes a main body and a protruding portion, the protruding portion protrudes from the main body along the first direction, the main body is connected to the first pole ear, and the protruding portion is connected to the first electrode terminal; wherein, along the first direction, the main body has a first surface closest to the first wall portion, and the second insulating member covers at least a portion of the first surface.

[0011] In the above technical solution, the first surface is the surface of the main body that is closest to the first wall portion, that is, the first surface is the surface on the first current collecting member that is most likely to contact the first wall portion and cause a short circuit. By making the second insulating member cover at least a portion of the first surface so as to insulate and isolate the first current collecting member from the first wall portion, the second insulating member has a better insulating effect, which is beneficial to reducing the risk of short circuit in the battery cell and improving the reliability of the battery cell.

[0012] As an optional technical solution of an embodiment of the present application, along the first direction, the main body portion includes a first connecting portion and a second connecting portion, the second connecting portion is connected to the first connecting portion, the first pole ear is connected to the first connecting portion, and along the first direction, the surface of the first connecting portion facing the first wall portion is the first surface, the second connecting portion has a second surface facing the first wall portion, the first surface is closer to the first wall portion than the second surface, the protrusion protrudes from the second surface, and the second insulating member covers at least a portion of the second surface.

[0013] In the above technical solution, the main body includes a first surface and a second surface, wherein the first surface is the surface closest to the first wall, and the distance between the second surface and the first wall is greater than the distance between the first surface and the first wall. Since both the first surface and the second surface have the risk of short circuit due to contact with the first wall, the second insulating member is made to cover at least a portion of the first surface and at least a portion of the second surface so as to better insulate and isolate the first current collecting member from the first wall, so that the second insulating member has a better insulation effect, which is conducive to further reducing the risk of short circuit of the battery cell and further improving the reliability of the battery cell.

[0014] As an optional technical solution of an embodiment of the present application, the battery cell includes a plurality of electrode assemblies, and the plurality of electrode assemblies are arranged along a second direction, and the second direction intersects with the first direction; the second surface includes a covering area covered by the second insulating member and a non-covering area not covered by the second insulating member, and along the second direction, both sides of the non-covering area are connected to the covering area, and the protrusion is arranged in the non-covering area.

[0015] In the above technical solution, both sides of the non-covered area are connected to the covered area. In comparison, the covered area is closer to another battery cell adjacent to the battery cell. When another battery cell has thermal runaway, along the second direction, the temperature of the area near the two ends of the first insulating member is higher and easier to melt, while the temperature of the first insulating member near the middle is lower and relatively difficult to melt. The covered area corresponds to the area where the first insulating member is easy to melt, and the non-covered area corresponds to the area where the first insulating member is relatively difficult to melt. The first insulating member and the second insulating member cooperate to more effectively insulate and isolate the first current collecting member and the first wall portion, which is beneficial to reduce the risk of short circuit in the battery cell and improve the reliability of the battery cell.

[0016] As an optional technical solution of an embodiment of the present application, the battery cell includes a plurality of electrode assemblies, and the plurality of electrode assemblies are arranged along a second direction, and the second direction intersects with the first direction; the main body includes a plurality of first connecting portions, and the plurality of first connecting portions are arranged at intervals along the second direction, and the second connecting portion connects the plurality of first connecting portions, and each of the first connecting portions is connected to the first pole ear of one of the electrode assemblies.

[0017] In the above technical solution, each first connecting portion is connected to the first pole ear of an electrode assembly, and the second connecting portion is connected to multiple first connecting portions to realize the electrical connection between the first current collecting component and the first pole ears of multiple electrode assemblies 22. The first pole ears and the first electrode terminal of the multiple electrode assemblies are connected by the first current collecting component, which is conducive to reducing the difficulty of assembly between the first pole ears and the first electrode terminal.

[0018] As an optional technical solution of an embodiment of the present application, along the first direction, the second insulating member completely covers the area of ​​the surface of the main body portion facing the first wall portion that is not occupied by the protrusion.

[0019] In the above technical solution, by completely covering the area of ​​the surface of the main body facing the first wall portion that is not occupied by the protrusion with the second insulating member, the second insulating member has a better insulation effect, further reducing the risk of short circuit in the battery cell, which is beneficial to improving the reliability of the battery cell.

[0020] As an optional technical solution of the embodiment of the present application, the second insulating member is provided with an avoidance hole, and the protrusion passes through the avoidance hole and is connected to the first electrode terminal.

[0021] In the above technical solution, the avoidance hole is provided on the second insulating member to avoid the protrusion, so that the protrusion is connected to the first electrode terminal, which is conducive to reducing the material consumption of the second insulating member. In addition, since the protrusion is inserted into the avoidance hole, the avoidance hole and the protrusion cooperate to limit the second insulating member, so that the second insulating member is not easy to deviate or shift, so that the second insulating member can better play an insulating role.

[0022] As an optional technical solution of an embodiment of the present application, the first electrode tab is connected to a side of the first current collecting member away from the first wall portion.

[0023] In the above technical solution, when the first pole ear is connected to the side of the first current collecting member away from the first wall portion, the first current collecting member is more likely to contact the first wall portion and cause a short circuit than the first pole ear. At this time, the second insulating member is connected to the first current collecting member, and the second insulating member is at least partially located between the first current collecting member and the first wall portion to insulate and isolate the first current collecting member from the first wall portion. This allows the second insulating member to exert a better insulating effect, further reduce the risk of short circuit in the battery cell, and is beneficial to improving the reliability of the battery cell.

[0024] As an optional technical solution of an embodiment of the present application, the battery cell includes a first electrode terminal, which is arranged on the first wall portion; the first electrode lead-out portion includes a first pole ear and a first current collecting member, the first pole ear is connected to one end of the main body facing the first wall portion along the first direction, the first pole ear is connected to the surface of the first current collecting member facing the first wall portion, and the first current collecting member is connected to the first electrode terminal; wherein the second insulating member is connected to the surface of the first pole ear closest to the first wall portion.

[0025] In the above technical solution, the first pole ear is connected to the first electrode terminal through the first current collecting member, but the first pole ear is connected to the surface of the first current collecting member facing the first wall portion. The first pole ear is more likely to contact the first wall portion and cause a short circuit than the first current collecting member. At this time, the second insulating member is connected to the surface of the first pole ear closest to the first wall portion to insulate the first pole ear from the first wall portion, which can enable the second insulating member to exert a better insulation effect, further reduce the risk of short circuit in the battery cell, and help improve the reliability of the battery cell.

[0026] As an optional technical solution of an embodiment of the present application, the battery cell includes a first electrode terminal, which is arranged on the first wall portion; the first electrode lead-out portion includes a first pole lug, which is connected to the first electrode terminal; wherein the second insulating member is connected to the first pole lug, and along the first direction, the second insulating member is at least partially located between the first pole lug and the first wall portion.

[0027] In the above technical solution, the first pole lug is directly connected to the first electrode terminal, the second insulating member is connected to the first pole lug, and the second insulating member is at least partially located between the first pole lug and the first wall portion to insulate the first pole lug from the first wall portion, so that the second insulating member has a better insulation effect, further reducing the risk of short circuit in the battery cell, which is beneficial to improving the reliability of the battery cell.

[0028] As an optional technical solution of the embodiment of the present application, along the first direction, the projection of the second insulating member does not overlap with the projection of the first electrode terminal.

[0029] In the above technical solution, by making the projection of the second insulating member along the first direction not overlap with the projection of the first electrode terminal along the first direction, the risk of the second insulating member interfering with the connection between the first electrode terminal and the first electrode tab is reduced, thereby facilitating the connection between the first electrode terminal and the first electrode tab.

[0030] As an optional technical solution of the embodiment of the present application, the second insulating member is provided with an avoidance hole, and the first electrode terminal passes through the avoidance hole to be connected with the first electrode tab.

[0031] In the above technical solution, the avoidance hole is provided on the second insulating member to avoid the first electrode terminal, so as to facilitate the connection between the first electrode tab and the first electrode terminal, which is conducive to reducing the material consumption of the second insulating member. In addition, since the first electrode terminal is inserted into the avoidance hole, the avoidance hole cooperates with the first electrode terminal to limit the second insulating member, so that the second insulating member is not easy to deviate or shift, so that the second insulating member can better play an insulating role.

[0032] As an optional technical solution of the embodiment of the present application, the second insulating member is bonded to the first electrode lead-out portion.

[0033] In the above technical solution, by bonding the second insulating member to the first electrode lead-out portion, the second insulating member is simply and conveniently connected to the first electrode lead-out portion, which is beneficial to limit the position of the second insulating member so that the second insulating member can stably exert its insulating effect.

[0034] As an optional technical solution of the embodiment of the present application, the second insulating member is coated on the first electrode lead-out portion.

[0035] In the above technical solution, by covering the first electrode lead-out portion with the second insulating member, on the one hand, the first electrode lead-out portion can be well covered, thereby isolating the first electrode lead-out portion from the first wall portion. On the other hand, when the second insulating member is covered with the first electrode lead-out portion, the second insulating member is not likely to deviate or shift relative to the first electrode lead-out portion, so that the second insulating member can better play an insulating role.

[0036] As an optional technical solution of an embodiment of the present application, the second insulating member is an insulating film connected to the first electrode lead-out portion.

[0037] In the above technical solution, the second insulating member is an insulating film, which can effectively insulate and isolate the first electrode lead portion and the first wall portion without occupying too much space inside the shell, so that the battery cell can still have a high energy density.

[0038] As an optional technical solution of an embodiment of the present application, the material damage temperature of the second insulating member is greater than or equal to 300°C.

[0039] In the above technical solution, when another battery cell adjacent to the battery cell experiences thermal runaway, the temperature inside the battery cell can rise to 200° C. However, the material damage temperature of the second insulating member is greater than or equal to 300° C. Therefore, when another battery cell adjacent to the battery cell experiences thermal runaway, it is not easy to cause the second insulating member to melt, so that the second insulating member can play an insulating isolation role and reduce the risk of short circuit of the battery cell.

[0040] As an optional technical solution of an embodiment of the present application, the material of the second insulating member includes at least one of polyimide, polyetheretherketone, and polytetrafluoroethylene.

[0041] In the above technical solution, polyimide, polyetheretherketone and polytetrafluoroethylene have good high temperature resistance and good insulation effect. They can insulate the first electrode lead-out portion from the first wall portion when the temperature is higher than 200°C, reduce the risk of short circuit of the battery cell, and thus improve the reliability of the battery cell.

[0042] As an optional technical solution of an embodiment of the present application, the positive electrode material of the battery cell includes lithium-containing phosphate.

[0043] In the above technical solution, the positive electrode material includes a battery cell containing lithium phosphate, which will generate a large amount of heat when thermal runaway occurs, thereby easily causing the first insulating member of the battery cell and another adjacent battery cell to melt. By arranging a second insulating member in the battery cell, it is more conducive to reducing the risk of short circuit caused by contact between the first electrode lead-out portion and the first wall portion, that is, it is better to arrange the second insulating member in the battery cell containing lithium phosphate.

[0044] As an optional technical solution of an embodiment of the present application, the lithium-containing phosphate includes at least one of lithium iron phosphate, a composite material of lithium iron phosphate and carbon, lithium manganese phosphate, a composite material of lithium manganese phosphate and carbon, lithium iron manganese phosphate, and a composite material of lithium iron manganese phosphate and carbon.

[0045] In a second aspect, an embodiment of the present application further provides a battery, which includes the above-mentioned battery cell.

[0046] In a third aspect, an embodiment of the present application further provides an electrical device, wherein the electrical device comprises the above-mentioned battery cell. BRIEF DESCRIPTION OF THE DRAWINGS

[0047] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings required for use in the embodiments will be briefly introduced below. It should be understood that the following drawings only show certain embodiments of the present application and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other related drawings can be obtained based on these drawings without paying creative work.

[0048] Figure 1 A schematic diagram of the structure of a vehicle provided in some embodiments of the present application;

[0049] Figure 2 An exploded view of a battery provided for some embodiments of the present application;

[0050] Figure 3 A schematic diagram of the structure of a battery cell provided in some embodiments of the present application;

[0051] Figure 4 An exploded view of a battery cell provided for some embodiments of the present application;

[0052] Figure 5 A schematic diagram of a structure in which a second insulating member provided in some embodiments of the present application is connected to a first current collecting member;

[0053] Figure 6 An exploded view of a second insulating member and a first current collecting member provided in some embodiments of the present application;

[0054] Figure 7 A schematic diagram of a structure in which a second insulating member is connected to a first current collecting member provided in some other embodiments of the present application;

[0055] Figure 8 An exploded view of a second insulating member and a first current collecting member provided in some other embodiments of the present application;

[0056] Fig. 9 A schematic diagram of a structure in which a second insulating member is connected to a first current collecting member provided in some other embodiments of the present application;

[0057] Fig.10 An exploded view of a second insulating member and a first current collecting member provided in some other embodiments of the present application;

[0058] Fig.11 An exploded view of a battery cell is provided for some embodiments of the present application.

[0059] Icons: 10-box; 11-first part; 12-second part; 20-battery cell; 21-housing; 211-end cover; 212-housing; 213-first wall; 22-electrode assembly; 221-main body; 222-first electrode lead; 2221-first pole ear; 2222-first current collecting member; 22221-main body; 22222-protrusion; 2222a-first surface; 2222b-second surface; 2222c-third surface ;22223-first connecting portion; 22224-second connecting portion; 22225-covering area; 22226-non-covering area; 223-second electrode lead-out portion; 2231-second pole ear; 2232-second current collecting member; 23-first insulating member; 24-second insulating member; 241-avoidance hole; 25-first electrode terminal; 26-third insulating member; 27-second electrode terminal; 100-battery; 200-controller; 300-motor; 1000-vehicle. DETAILED DESCRIPTION

[0060] In order to make the purpose, technical solution and advantages of the embodiments of the present application clearer, the technical solution in the embodiments of the present application will be clearly described below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of this application.

[0061] Unless otherwise defined, all technical and scientific terms used in this application have the same meanings as those commonly understood by technicians in the technical field of this application; 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" in the specification and claims of this application and the above-mentioned drawings and any variations thereof are intended to cover non-exclusive inclusions. The terms "first", "second", etc. in the specification and claims of this application or the above-mentioned drawings are used to distinguish different objects, rather than to describe a specific order or a primary and secondary relationship.

[0062] Reference to "embodiment" in this application means that a particular feature, structure, or characteristic described in conjunction with the embodiment may be included in at least one embodiment of the present application. The appearance of the phrase in various places in the specification does not necessarily refer to the same embodiment, nor is it an independent or alternative embodiment that is mutually exclusive with other embodiments.

[0063] In the description of this application, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected", "connected", and "attached" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a direct connection, or an indirect connection through an intermediate medium, or it can be the internal communication of two elements. For ordinary technicians in this field, the specific meanings of the above terms in this application can be understood according to specific circumstances.

[0064] The term "and / or" in this application is only a description of the association relationship of associated objects, indicating that there can be three relationships. For example, A and / or B can represent: A exists alone, A and B exist at the same time, and B exists alone. In addition, the character " / " in this application generally indicates that the associated objects before and after are in an "or" relationship.

[0065] In the embodiments of the present application, the same reference numerals represent the same components, and for the sake of brevity, detailed descriptions of the same components are omitted in different embodiments. It should be understood that the thickness, length, width and other dimensions of various components in the embodiments of the present application shown in the drawings, as well as the overall thickness, length, width and other dimensions of the integrated device are only exemplary descriptions and should not constitute any limitation to the present application.

[0066] The term "plurality" used in the present application refers to two or more (including two).

[0067] In the embodiment of the present application, the battery cell may be a secondary battery. A secondary battery refers to a battery cell that can be continuously used by activating active materials by charging after the battery cell is discharged.

[0068] The battery cell can be a lithium ion battery, a sodium ion battery, a sodium lithium ion battery, a lithium metal battery, a sodium metal battery, a lithium sulfur battery, a magnesium ion battery, a nickel hydrogen battery, a nickel cadmium battery, a lead storage battery, etc., which is not limited in the embodiments of the present application.

[0069] A battery cell generally includes an electrode assembly. 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 removed between the positive electrode and the negative electrode. The separator is set between the positive electrode and the negative electrode to prevent the positive and negative electrodes from short-circuiting, while allowing active ions to pass through.

[0070] In some embodiments, the positive electrode may be a positive electrode sheet, and the positive electrode sheet may include a positive electrode current collector and a positive electrode active material disposed on at least one surface of the positive electrode current collector.

[0071] As an example, the positive electrode current collector has two surfaces facing each other in its thickness direction, and the positive electrode active material is disposed on either or both of the two facing surfaces of the positive electrode current collector.

[0072] As an example, the positive electrode current collector may be a metal foil or a composite current collector. For example, as the metal foil, aluminum with a silver-plated surface, stainless steel with a silver-plated surface, stainless steel, copper, aluminum, nickel, carbon electrode, carbon, nickel or titanium, etc. may be used. The composite current collector may include a polymer material base and a metal layer. The composite current collector may be formed by forming a metal material (aluminum, aluminum alloy, nickel, nickel alloy, titanium, titanium alloy, silver and silver alloy, etc.) on a polymer material substrate (such as a substrate of polypropylene, polyethylene terephthalate, polybutylene terephthalate, polystyrene, polyethylene, etc.).

[0073] As an example, the positive electrode active material may include at least one of the following materials: lithium-containing phosphates, lithium transition metal oxides and their respective modified compounds. However, the present application is not limited to these materials, and other traditional materials that can be used as positive electrode active materials for batteries can also be used. These positive electrode active materials can be used alone or in combination of two or more. Among them, examples of lithium-containing phosphates may include, but are not limited to, at least one of lithium iron phosphate (such as LiFePO4 (also referred to 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 iron manganese phosphate, and a composite material of lithium iron manganese phosphate and carbon. 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 / 3 Mn 1 / 3 O2 (also referred to as NCM 333 )、LiNi 0.5 Co 0.2 Mn 0.3 O2 (also referred to as NCM 523 )、LiNi 0.5 Co 0.25 Mn 0.25 O2 (also referred to as NCM 211 )、LiNi 0.6 Co 0.2 Mn 0.2 O2 (also referred to as NCM 622 )、LiNi 0.8 Co 0.1 Mn 0.1 O2 (also referred to as NCM 811 ), lithium nickel cobalt aluminum oxide (such as LiNi 0.85 Co 0.15 Al 0.05O2) and its modified compounds, etc.

[0074] In some embodiments, the positive electrode may be a foamed metal. The foamed metal may be a nickel foam, a copper foam, an aluminum foam, an alloy foam, etc. When the foamed metal is used as the positive electrode, the positive electrode active material may not be provided on the surface of the foamed metal, but of course, the positive electrode active material may also be provided. As an example, a lithium source material, potassium metal or sodium metal may also be filled or / and deposited in the foamed metal, and the lithium source material is lithium metal and / or a lithium-rich material.

[0075] In some embodiments, the negative electrode may be a negative electrode sheet, and the negative electrode sheet may include a negative electrode current collector.

[0076] As an example, the negative electrode current collector may be a metal foil, a foamed metal or a composite current collector. For example, as the metal foil, aluminum or stainless steel treated with silver, stainless steel, copper, aluminum, nickel, carbon electrode, nickel or titanium, etc. may be used. The foamed metal may be a nickel foam, a copper foam, an aluminum foam, an alloy foam, etc. The composite current collector may include a polymer material base and a metal layer. The composite current collector may be formed by forming a metal material (copper, copper alloy, nickel, nickel alloy, titanium, titanium alloy, silver and silver alloy, etc.) on a polymer material substrate (such as a substrate of polypropylene, polyethylene terephthalate, polybutylene terephthalate, polystyrene, polyethylene, etc.).

[0077] As an example, the negative electrode sheet may include a negative electrode current collector and a negative electrode active material disposed on at least one surface of the negative electrode current collector.

[0078] As an example, the negative electrode current collector has two surfaces facing each other in its thickness direction, and the negative electrode active material is disposed on either or both of the two facing surfaces of the negative electrode current collector.

[0079] As an example, the negative electrode active material may adopt the negative electrode active material for battery cells known in the art. As an example, the negative electrode active material may include at least one of the following materials: artificial graphite, natural graphite, soft carbon, hard carbon, silicon-based materials, tin-based materials, lithium titanate, etc. The silicon-based material may be selected from at least one of elemental silicon, silicon oxide compounds, silicon-carbon composites, silicon-nitrogen composites, and silicon alloys. The tin-based material may be selected from at least one of elemental tin, tin oxide compounds, and tin alloys. However, the present application is not limited to these materials, and other traditional materials that can be used as negative electrode active materials for batteries may also be used. These negative electrode active materials may be used alone or in combination of two or more.

[0080] In some embodiments, the material of the positive electrode current collector may be aluminum, and the material of the negative electrode current collector may be copper.

[0081] In some embodiments, the electrode assembly further includes a separator disposed between the positive electrode and the negative electrode.

[0082] In some embodiments, the separator is a separator membrane. There may be many types of separator membranes, and any known porous separator membrane with good chemical stability and mechanical stability may be selected.

[0083] As an example, the material of the separator may include at least one of glass fiber, non-woven fabric, polyethylene, polypropylene and polyvinylidene fluoride. The separator may be a single-layer film or a multi-layer composite film. When the separator is a multi-layer composite film, the materials of each layer may be the same or different. The separator may be a separate component located between the positive and negative electrodes, or may be attached to the surface of the positive and negative electrodes.

[0084] In some embodiments, the separator is a solid electrolyte, which is disposed between the positive electrode and the negative electrode and serves to transmit ions and isolate the positive and negative electrodes.

[0085] In some embodiments, the battery cell further includes an electrolyte, which plays a role in conducting ions between the positive and negative electrodes. The electrolyte can be liquid, gel or solid. Among them, the liquid electrolyte includes an electrolyte salt and a solvent.

[0086] In some embodiments, the electrolyte salt may include at least one of lithium hexafluorophosphate, lithium tetrafluoroborate, lithium perchlorate, lithium hexafluoroarsenate, lithium bisfluorosulfonyl imide, lithium bistrifluoromethanesulfonyl imide, lithium trifluoromethanesulfonate, lithium difluorophosphate, lithium difluorooxalatoborate, lithium dioxalatoborate, lithium difluorodioxalatophosphate, and lithium tetrafluorooxalatophosphate.

[0087] 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, cyclopentane, dimethyl sulfone, methyl ethyl sulfone and diethyl sulfone. The solvent may also be an ether solvent. The ether solvent may 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.

[0088] Among them, the gel electrolyte includes a skeleton network with a polymer as the electrolyte, combined with an ionic liquid-lithium salt.

[0089] Among them, solid electrolytes include polymer solid electrolytes, inorganic solid electrolytes, and composite solid electrolytes.

[0090] As an example, the polymer solid electrolyte may be polyether (polyethylene oxide), polysiloxane, polycarbonate, polyacrylonitrile, polyvinylidene fluoride, polymethyl methacrylate, a single ion polymer, polyionic liquid-lithium salt, cellulose, and the like.

[0091] As an example, the inorganic solid electrolyte may include an oxide solid electrolyte (crystalline perovskite, sodium superconducting ion conductor, garnet, amorphous LiPON film), a sulfide solid electrolyte (crystalline lithium superion conductor (lithium germanium phosphosulfide, silver germanium sulfide), amorphous sulfide) and one or more of a halide solid electrolyte, a nitride solid electrolyte and a hydride solid electrolyte.

[0092] As an example, the composite solid electrolyte is formed by adding an inorganic solid electrolyte filler to a polymer solid electrolyte.

[0093] In some embodiments, the electrode assembly is a wound structure, wherein the positive electrode sheet and the negative electrode sheet are wound into the wound structure.

[0094] In some embodiments, the electrode assembly is a laminate structure.

[0095] As an example, a plurality of positive electrode sheets and a plurality of negative electrode sheets may be provided respectively, and the plurality of positive electrode sheets and the plurality of negative electrode sheets may be alternately stacked.

[0096] As an example, a plurality of positive electrode sheets may be provided, and the negative electrode sheet may be folded to form a plurality of stacked folded segments, with a positive electrode sheet being sandwiched between adjacent folded segments.

[0097] As an example, both the positive electrode sheet and the negative electrode sheet are folded to form a plurality of folded sections that are stacked.

[0098] As an example, a plurality of separators may be provided, each of which is provided between any adjacent positive electrode sheets or negative electrode sheets.

[0099] As an example, the separator may be disposed continuously, and may be disposed between any adjacent positive electrode sheets or negative electrode sheets by folding or winding.

[0100] In some embodiments, the shape of the electrode assembly can be cylindrical, flat, or polygonal.

[0101] In some embodiments, the electrode assembly is provided with tabs, which can lead current out of the electrode assembly. The tabs include a positive tab and a negative tab.

[0102] In some embodiments, the battery cell may include a housing. The housing is used to encapsulate components such as the electrode assembly and the electrolyte. The housing may be a steel housing, an aluminum housing, a plastic housing (such as polypropylene), a composite metal housing (such as a copper-aluminum composite housing), or an aluminum-plastic film.

[0103] As an example, the battery cell may be a cylindrical battery cell, a prismatic battery cell, a soft-pack battery cell or a battery cell of other shapes. The prismatic battery cell includes but is not limited to a square-shell battery cell, a blade-shaped battery cell, a polygonal battery, such as a hexagonal battery, etc.

[0104] The battery mentioned in the embodiments of the present application refers to a single physical module including one or more battery cells to provide higher voltage and capacity.

[0105] 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.

[0106] In some embodiments, the battery may be a battery pack, which includes a case and battery cells, wherein the battery cells or battery modules are accommodated in the case.

[0107] In some embodiments, the box body can be used as a part of the chassis structure of the vehicle. For example, part of the box body can become at least a part of the floor of the vehicle, or part of the box body can become at least a part of the cross beam and longitudinal beam of the vehicle.

[0108] In some embodiments, the battery may be an energy storage device, which includes an energy storage container, an energy storage cabinet, and the like.

[0109] At present, from the perspective of market development, the application of batteries is becoming more and more extensive. Batteries are not only used in energy storage power systems such as hydropower, thermal power, wind power and solar power stations, but also widely used in electric vehicles such as electric bicycles, electric motorcycles, electric cars, as well as military equipment and aerospace and other fields. With the continuous expansion of battery application areas, its market demand is also constantly expanding.

[0110] The development of battery technology must consider many design factors at the same time, such as battery life, energy density, discharge capacity, charge and discharge rate and other performance parameters. In addition, the reliability of the battery must also be considered. However, the reliability of current batteries is poor.

[0111] Batteries generally include multiple battery cells to provide higher voltage and capacity. In a battery, if a battery cell experiences thermal runaway, the heat generated by the thermal runaway is easily transferred to the adjacent battery cells, so that the temperature of the adjacent battery cells can reach 200°C. However, the lower plastic of the battery cell (the insulating part used to insulate the end cap and the electrode assembly) will melt at 160-180°C, causing the end cap and the electrode assembly to come into direct contact and short-circuit, further increasing the temperature of the battery cell, and ultimately leading to heat diffusion, resulting in poor battery reliability.

[0112] In view of this, an embodiment of the present application provides a battery cell, the battery cell comprising a shell, an electrode assembly, a first insulating member and a second insulating member, the shell having a first wall portion, and the electrode assembly being accommodated in the shell. The electrode assembly comprises a first electrode lead-out portion and a main body portion, the first electrode lead-out portion being arranged at one end of the main body portion facing the first wall portion along a first direction. Along the first direction, the first insulating member is arranged on the surface of the first wall portion facing the electrode assembly, and the first insulating member is used to insulate and isolate the first electrode lead-out portion and the first wall portion. Along the first direction, at least a portion of the second insulating member is arranged between the first electrode lead-out portion and the first wall portion, the material damage temperature of the second insulating member is greater than the material damage temperature of the first insulating member, and the second insulating member is configured to insulate and isolate the first electrode lead-out portion and the first wall portion when the first insulating member melts.

[0113] The battery cell is provided with a first insulating member and a second insulating member. In normal use, the first insulating member and the second insulating member can both insulate and isolate the first electrode lead-out portion and the first wall portion, reducing the risk of the first electrode lead-out portion contacting the first wall portion and causing a short circuit. Since the material damage temperature of the second insulating member is greater than the material damage temperature of the first insulating member, when another battery cell adjacent to the battery cell experiences thermal runaway, causing the first insulating member of the battery cell to melt, the second insulating member can still play a role in insulating and isolating the first electrode lead-out portion and the first wall portion to a certain extent, reducing the risk of the first electrode lead-out portion contacting the first wall portion and causing a short circuit. In this way, even if another battery cell adjacent to the battery cell experiences thermal runaway, it is not easy to cause the battery cell to short-circuit and continue to cause thermal runaway, which is conducive to limiting heat diffusion and improving the reliability of the battery cell.

[0114] The technical solutions described in the embodiments of the present application are applicable to batteries and electrical equipment using batteries.

[0115] Electrical equipment may be vehicles, mobile phones, portable devices, laptops, ships, spacecraft, electric toys, and electric tools, etc. Spacecraft include airplanes, rockets, space shuttles, and spacecrafts, etc.; electric toys include fixed or mobile electric toys, such as game consoles, electric car toys, electric ship toys, and electric airplane toys, etc.; electric tools include metal cutting electric tools, grinding electric tools, assembly electric tools, and railway electric tools, such as electric drills, electric grinders, electric wrenches, electric screwdrivers, electric hammers, impact drills, concrete vibrators, and electric planers, etc. The embodiments of the present application do not impose any special restrictions on the above-mentioned electrical equipment.

[0116] For the convenience of description, the following embodiments are described by taking the electric device as a vehicle 1000 as an example.

[0117] Please refer to Figure 1 , Figure 1A schematic diagram of the structure of a vehicle 1000 provided for some embodiments of the present application. The vehicle 1000 may be a fuel vehicle, a gas vehicle or a new energy vehicle, and the new energy vehicle may be a pure electric vehicle, a hybrid vehicle or an extended-range vehicle, etc. A battery 100 is provided inside the vehicle 1000, and the battery 100 may be provided at the bottom, head or tail of the vehicle 1000. The battery 100 may be used to power the vehicle 1000, for example, the battery 100 may be used as an operating power source for the vehicle 1000. The vehicle 1000 may also include a controller 200 and a motor 300, and the controller 200 is used to control the battery 100 to power the motor 300, for example, for starting, navigating and driving the vehicle 1000.

[0118] In some embodiments of the present application, the battery 100 can not only serve as an operating power source for the vehicle 1000, but also serve as a driving power source for the vehicle 1000, replacing or partially replacing fuel or natural gas to provide driving power for the vehicle 1000.

[0119] Please refer to Figure 2 , Figure 2 An exploded view of a battery 100 provided in some embodiments of the present application. The battery 100 includes a box 10 and a battery cell 20, and the battery cell 20 is contained in the box 10. Among them, the box 10 is used to provide a storage space for the battery cell 20, and the box 10 can adopt a variety of structures. In some embodiments, the box 10 may include a first part 11 and a second part 12, the first part 11 and the second part 12 cover each other, and the first part 11 and the second part 12 jointly define a storage space for accommodating the battery cell 20. The second part 12 may be a hollow structure with one end open, the first part 11 may be a plate-like structure, and the first part 11 covers the open side of the second part 12, so that the first part 11 and the second part 12 jointly define a storage space; the first part 11 and the second part 12 may also be hollow structures with one side open, and the open side of the first part 11 covers the open side of the second part 12. Of course, the box 10 formed by the first part 11 and the second part 12 may be in a variety of shapes, such as a cylinder, a cuboid, etc.

[0120] In the battery 100, there may be multiple battery cells 20, and the multiple battery cells 20 may be connected in series, in parallel, or in a mixed connection. A mixed connection means that the multiple battery cells 20 are both connected in series and in parallel. The multiple battery cells 20 may be directly connected in series, in parallel, or in a mixed connection, and then the whole formed by the multiple battery cells 20 is accommodated in the box 10; of course, the battery 100 may also be a battery module formed by connecting multiple battery cells 20 in series, in parallel, or in a mixed connection, and then the multiple battery modules are connected in series, in parallel, or in a mixed connection to form a whole, and accommodated in the box 10. The battery 100 may also include other structures, for example, the battery 100 may also include a busbar component for realizing electrical connection between the multiple battery cells 20.

[0121] Each battery cell 20 may be a secondary battery cell or a primary battery cell, or a lithium-sulfur battery cell, a sodium-ion battery cell, or a magnesium-ion battery cell, but is not limited thereto. The battery cell 20 may be cylindrical, flat, rectangular, or in other shapes.

[0122] Please refer to Figure 3 and Figure 4 , Figure 3 This is a schematic diagram of the structure of a battery cell 20 provided in some embodiments of the present application. Figure 4 An exploded view of a battery cell 20 provided in some embodiments of the present application. The embodiments of the present application provide a battery cell 20, which includes a housing 21, an electrode assembly 22, a first insulating member 23, and a second insulating member 24. The housing 21 has a first wall portion 213, and the electrode assembly 22 is accommodated in the housing 21. The electrode assembly 22 includes a first electrode lead-out portion 222 and a main body portion 221, and the first electrode lead-out portion 222 is arranged at one end of the main body portion 221 facing the first wall portion 213 along the first direction. Along the first direction, the first insulating member 23 is arranged on the surface of the first wall portion 213 facing the electrode assembly 22, and the first insulating member 23 is used to insulate and isolate the first electrode lead-out portion 222 and the first wall portion 213. Along the first direction, at least a portion of the second insulating member 24 is arranged between the first electrode lead-out portion 222 and the first wall portion 213, the material damage temperature of the second insulating member 24 is greater than the material damage temperature of the first insulating member 23, and the second insulating member 24 is configured to insulate and isolate the first electrode lead-out portion 222 and the first wall portion 213 when the first insulating member 23 melts.

[0123] The battery cell 20 refers to the smallest unit constituting the battery 100 .

[0124] The housing 21 includes an end cap 211 and a shell 212. The shell 212 has a receiving space with one end open, and the receiving space is used to receive the electrode assembly 22. The end cap 211 is connected to the shell 212 and closes the opening.

[0125] The end cap 211 refers to a component that covers the opening of the shell 212 to isolate the internal environment of the battery cell 20 from the external environment. Without limitation, the shape of the end cap 211 can be adapted to the shape of the shell 212 to match the shell 212. Optionally, the end cap 211 can be made of a material with a certain hardness and strength (such as aluminum alloy), so that the end cap 211 is not easily deformed when squeezed and collided, so that the battery cell 20 can have a higher structural strength and the safety performance can also be improved. The material of the end cap 211 can also be a variety of materials, such as copper, iron, aluminum, stainless steel, aluminum alloy, plastic, etc., and the embodiments of the present application do not impose any special restrictions on this.

[0126] The shell 212 is a component used to cooperate with the end cap 211 to form the internal environment of the battery cell 20, wherein the formed internal environment can be used to accommodate the electrode assembly 22, the electrolyte and other components. The shell 212 and the end cap 211 can be independent components, and an opening can be set on the shell 212, and the internal environment of the battery cell 20 is formed by covering the opening with the end cap 211 at the opening. Without limitation, the end cap 211 and the shell 212 can also be integrated. Specifically, the end cap 211 and the shell 212 can form a common joint surface before other components are put into the shell, and when the interior of the shell 212 needs to be encapsulated, the end cap 211 covers the shell 212. The shell 212 can be of various shapes and sizes, such as a rectangular parallelepiped, a cylindrical shape, a hexagonal prism, etc. Specifically, the shape of the shell 212 can be determined according to the specific shape and size of the electrode assembly 22. The material of the shell 212 can be various, such as copper, iron, aluminum, stainless steel, aluminum alloy, plastic, etc., and the embodiment of the present application does not impose any special restrictions on this.

[0127] The electrode assembly 22 is a component in the battery cell 20 where electrochemical reactions occur. One or more electrode assemblies 22 may be included in the housing 21. The electrode assembly 22 is mainly formed by winding or stacking positive and negative electrode sheets, and a separator is usually provided between the positive and negative electrode sheets. The parts of the positive and negative electrode sheets with active materials constitute the main body 221 of the electrode assembly 22, and the parts of the positive and negative electrode sheets without active materials each constitute a pole ear. The positive pole ear and the negative pole ear may be located together at one end of the main body or respectively at both ends of the main body 221. During the charge and discharge process of the battery 100, the positive electrode active material and the negative electrode active material react with the electrolyte.

[0128] The first wall portion 213 may be an end cover 211 of the housing 21, or may be a wall of the shell 212 of the housing 21. Figure 3 and Figure 4In the embodiment, the first wall portion 213 is the end cover 211. In other embodiments, the first wall portion 213 may be a bottom wall of the housing 212 opposite to the end cover 211. In still other embodiments, the first wall portion 213 may also be a side wall of the housing 212 adjacent to and connected to the end cover 211.

[0129] The first electrode lead-out portion 222 is a structure for leading out the electric energy of the main body 221 or introducing the electric energy into the main body 221. The first electrode lead-out portion 222 includes at least the above-mentioned positive electrode ear or negative electrode ear, and the first electrode lead-out portion 222 may also include other electrical connection components connected to the positive electrode ear or the negative electrode ear. The first electrode lead-out portion 222 is arranged at one end of the main body 221 facing the first wall portion 213 along the first direction. In other words, the first electrode lead-out portion 222 is located between the first wall portion 213 and the main body 221 along the first direction.

[0130] Please refer to Figure 3 and Figure 4 , the first direction may be the X direction shown in the figure.

[0131] The first insulating member 23 is commonly called lower plastic, and is disposed inside the first wall portion 213. The first insulating member 23 is used to isolate the first electrode lead-out portion 222 from the first wall portion 213 to reduce the risk of short circuit. For example, the insulating member may be plastic, rubber, or the like.

[0132] The second insulating member 24 is partially or completely disposed between the first electrode lead-out portion 222 and the first wall portion 213 along the first direction to insulate and isolate the first electrode lead-out portion 222 from the first wall portion 213. When the battery cell 20 is in normal use, both the first insulating member 23 and the second insulating member 24 can play the role of insulating and isolating the first electrode lead-out portion 222 from the first wall portion 213.

[0133] The material damage temperature of a substance can be the melting point of the substance or the decomposition temperature of the substance. If a substance undergoes a decomposition reaction at a certain temperature, the temperature is the decomposition temperature of the substance. If a substance has both a melting point and a decomposition temperature, the decomposition temperature is the material damage temperature of the substance. If a substance only has a melting point but no decomposition temperature, the melting point is the material damage temperature of the substance. If a substance only has a decomposition temperature but no melting point, the decomposition temperature is the material damage temperature of the substance.

[0134] The material damage temperature of the second insulating member 24 is greater than the material damage temperature of the first insulating member 23. When the battery cell 20 experiences thermal runaway, the first insulating member 23 will first reach the material damage temperature and melt. When the first insulating member 23 melts, the second insulating member 24 can continue to insulate and isolate the first electrode lead-out portion 222 and the first wall portion 213, thereby reducing the risk of short circuit caused by contact between the first electrode lead-out portion 222 and the first wall portion 213.

[0135] The battery cell 20 is provided with a first insulating member 23 and a second insulating member 24. In normal use, the first insulating member 23 and the second insulating member 24 can both insulate and isolate the first electrode lead-out portion 222 and the first wall portion 213, reducing the risk of the first electrode lead-out portion 222 contacting the first wall portion 213 and causing a short circuit. Since the material damage temperature of the second insulating member 24 is greater than the material damage temperature of the first insulating member 23, when another battery cell 20 adjacent to the battery cell 20 undergoes thermal runaway, causing the first insulating member 23 of the battery cell 20 to melt, the second insulating member 24 can still play a role in insulating and isolating the first electrode lead-out portion 222 and the first wall portion 213 to a certain extent, reducing the risk of the first electrode lead-out portion 222 contacting the first wall portion 213 and causing a short circuit. In this way, even if another battery cell 20 adjacent to the battery cell 20 undergoes thermal runaway, it is not easy to cause the battery cell 20 to short-circuit and continue to cause thermal runaway, which is conducive to limiting heat diffusion and improving the reliability of the battery cell 20.

[0136] Please refer to Figure 3 , Figure 4 , Figure 5 and Figure 6 , Figure 5 A schematic structural diagram of the second insulating member 24 provided in some embodiments of the present application being connected to the first current collecting member 2222 . Figure 6 The exploded view of the second insulating member 24 and the first current collecting member 2222 provided in some embodiments of the present application. In some embodiments, the second insulating member 24 is connected to the first electrode lead-out portion 222.

[0137] The second insulating member 24 is directly connected to the first electrode lead-out portion 222. The first insulating member 23 may be fixedly connected to the first electrode lead-out portion 222, for example, the first connecting member is bonded to the first electrode lead-out portion 222. The first insulating member 23 may also be detachably connected to the first electrode lead-out portion 222, for example, the first insulating member 23 is clamped to the first electrode lead-out portion 222.

[0138] By connecting the second insulating member 24 to the first electrode lead-out portion 222, on one hand, since the first insulating member 23 is disposed on the surface of the first wall portion 213 facing the electrode assembly 22, it is more convenient to connect the second insulating member 24 to the first electrode lead-out portion 222, and it is not easy to interfere with the first insulating member 23. On the other hand, connecting the second insulating member 24 to the first electrode lead-out portion 222 limits the relative position of the second insulating member 24 and the first electrode lead-out portion 222, so that the second insulating member 24 can be stably located between the first electrode lead-out portion 222 and the first wall portion 213, thereby isolating the first electrode lead-out portion 222 from the first wall portion 213.

[0139] Please refer to Figure 3 , Figure 4 , Figure 5 and Figure 6 In some embodiments, the battery cell 20 includes a first electrode terminal 25, which is disposed on the first wall portion 213. The first electrode lead-out portion 222 includes a first electrode tab 2221 and a first current collecting member 2222, wherein the first electrode tab 2221 is connected to one end of the main body 221 facing the first wall portion 213 along the first direction, and the first current collecting member 2222 connects the first electrode terminal 25 and the first electrode tab 2221. The second insulating member 24 is connected to the first current collecting member 2222, and along the first direction, the second insulating member 24 is at least partially located between the first current collecting member 2222 and the first wall portion 213.

[0140] The first electrode terminal 25 is used to be electrically connected to the first electrode lead-out portion 222 to input or output electric energy of the battery cell 20 .

[0141] The first electrode lead-out portion 222 includes a first electrode tab 2221 and a first current collecting member 2222 , wherein the first electrode tab 2221 is a positive electrode tab or a negative electrode tab, and the first current collecting member 2222 connects the first electrode tab 2221 and the first electrode terminal 25 to guide the electrical energy of the electrode assembly 22 to the first electrode terminal 25 or receive the electrical energy introduced from the first electrode terminal 25 .

[0142] Optionally, the first current collecting member 2222 may be a sheet-like structure, for example, a transfer sheet.

[0143] The second insulating member 24 is connected to the first current collecting member 2222 , and is partially or entirely located between the first current collecting member 2222 and the first wall portion 213 along the first direction to insulate and isolate the first current collecting member 2222 from the first wall portion 213 .

[0144] The first pole ear 2221 is connected to the first electrode terminal 25 through the first current collecting member 2222. The first current collecting member 2222 is more likely to contact the first wall portion 213 and cause a short circuit than the first pole ear 2221. Therefore, the second insulating member 24 is connected to the first current collecting member 2222, and the second insulating member 24 is at least partially located between the first current collecting member 2222 and the first wall portion 213 to insulate and isolate the first current collecting member 2222 from the first wall portion 213, so that the second insulating member 24 has a better insulation effect, further reducing the risk of short circuit in the battery cell 20, which is beneficial to improving the reliability of the battery cell 20.

[0145] Please refer to Figure 5 and Figure 6In some embodiments, the first current collecting member 2222 includes a body portion 22221 and a protruding portion 22222, the protruding portion 22222 protrudes from the body portion 22221 along the first direction, the body portion 22221 is connected to the first electrode tab 2221, and the protruding portion 22222 is connected to the first electrode terminal 25. In the first direction, the body portion 22221 has a first surface 2222a closest to the first wall portion 213, and the second insulating member 24 covers at least a portion of the first surface 2222a.

[0146] The body portion 22221 is a portion of the first current collecting member 2222 mainly used for connecting with the first electrode tab 2221. The protrusion 22222 is a portion of the first current collecting member 2222 mainly used for connecting with the first electrode terminal 25. The protrusion 22222 is connected to the body portion 22221, and the protrusion 22222 protrudes from the body portion 22221 along the first direction.

[0147] Since the protrusion 22222 is the portion connected to the first electrode terminal 25, even if the first insulating member 23 is melted, the protrusion 22222 is not easy to contact the first wall portion 213 to cause a short circuit between the first electrode lead portion 222 and the first wall portion 213. Compared with the protrusion 22222, the body portion 22221 is more likely to contact the first wall portion 213 when the first insulating member 23 is melted to cause a short circuit between the first electrode lead portion 222 and the first wall portion 213.

[0148] The first surface 2222a is the surface of the body 22221 that is closest to the first wall 213 along the first direction, and is also the surface of the body 22221 that is most likely to contact with the first wall 213 and cause a short circuit. The second insulating member 24 may cover a portion of the first surface 2222a, or the second insulating member 24 may completely cover the first surface 2222a, thereby reducing the risk of the first surface 2222a contacting with the first wall 213 and causing a short circuit.

[0149] The first surface 2222a is the surface of the main body 22221 that is closest to the first wall portion 213, that is, the first surface 2222a is the surface on the first current collecting member 2222 that is most likely to contact the first wall portion 213 and cause a short circuit. By making the second insulating member 24 cover at least a portion of the first surface 2222a so as to insulate and isolate the first current collecting member 2222 from the first wall portion 213, the second insulating member 24 has a better insulation effect, which is beneficial to reducing the risk of short circuit in the battery cell 20 and improving the reliability of the battery cell 20.

[0150] Please refer to Figure 5 , Figure 6 , Figure 7 and Figure 8 , Figure 7Schematic diagram of the structure in which the second insulating member 24 is connected to the first current collecting member 2222 provided in some other embodiments of the present application. Figure 8 Exploded view of the second insulating member 24 and the first current collecting member 2222 provided for other embodiments of the present application. In other embodiments, along the first direction, the body portion 22221 includes a first connection portion 22223 and a second connection portion 22224, the second connection portion 22224 is connected to the first connection portion 22223, and the first pole ear 2221 is connected to the first connection portion 22223. Along the first direction, the surface of the first connection portion 22223 facing the first wall portion 213 is a first surface 2222a, and the second connection portion 22224 has a second surface 2222b facing the first wall portion 213, and the first surface 2222a is closer to the first wall portion 213 than the second surface 2222b. The protrusion 22222 protrudes from the second surface 2222b, and the second insulating member 24 covers at least a portion of the second surface 2222b.

[0151] The first connection portion 22223 is a portion of the body portion 22221 mainly used for connecting with the first tab 2221. The first connection portion 22223 is connected to the second connection portion 22224, and the protrusion 22222 is provided on the second connection portion 22224 to facilitate connection with the first electrode terminal 25, thereby reducing the difficulty of connecting the first electrode terminal 25 and the first tab 2221.

[0152] The surface of the first connection portion 22223 facing the first wall portion 213 along the first direction is the first surface 2222a. That is, the surface of the first connection portion 22223 facing the first wall portion 213 along the first direction is the surface of the body portion 22221 closest to the first wall portion 213.

[0153] The second surface 2222b is the surface of the second connection portion 22224 facing the first wall portion 213. Along the first direction, there is a height difference between the first surface 2222a and the second surface 2222b, and the first surface 2222a is closer to the first wall portion 213 than the second surface 2222b. In other words, along the first direction, the distance between the second surface 2222b and the first wall portion 213 is greater than the distance between the first surface 2222a and the first wall portion 213.

[0154] The protrusion 22222 protrudes from the second surface 2222b along the first direction. The second insulating member 24 may only cover a portion of the second surface 2222b, or may completely cover the second surface 2222b to reduce the risk of short circuit caused by the second surface 2222b contacting the first wall 213.

[0155] The body portion 22221 includes a first surface 2222a and a second surface 2222b, wherein the first surface 2222a is the surface closest to the first wall portion 213, and the distance between the second surface 2222b and the first wall portion 213 is greater than the distance between the first surface 2222a and the first wall portion 213. Since both the first surface 2222a and the second surface 2222b have the risk of short circuit due to contact with the first wall portion 213, the second insulating member 24 is made to cover at least a portion of the first surface 2222a and at least a portion of the second surface 2222b, so as to better insulate and isolate the first current collecting member 2222 from the first wall portion 213, so that the second insulating member 24 has a better insulation effect, which is conducive to further reducing the risk of short circuit of the battery cell 20 and further improving the reliability of the battery cell 20.

[0156] Optionally, in some embodiments, the main body 22221 also includes a third surface 2222c connecting the first surface 2222a and the second surface 2222b, and the second insulating member 24 at least partially covers the third surface 2222c. For example, the second insulating member 24 can be in contact with and cover the third surface 2222c.

[0157] Please refer to Figure 4 , Figure 5 , Figure 6 , Figure 7 and Figure 8 In some embodiments, the battery cell 20 includes a plurality of electrode assemblies 22, and the plurality of electrode assemblies 22 are arranged along a second direction, and the second direction intersects with the first direction. The second surface 2222b includes a covering area 22225 covered by the second insulating member 24 and a non-covering area 22226 not covered by the second insulating member 24, and along the second direction, both sides of the non-covering area 22226 are connected to the covering area 22225. The protrusion 22222 is disposed in the non-covering area 22226.

[0158] The second direction is the arrangement direction of the plurality of electrode assemblies 22. Figure 4 , the second direction may be the Y direction shown in the figure. The angle between the second direction and the first direction may be an acute angle or a right angle. Figure 4 In the illustrated embodiment, the second direction is perpendicular to the first direction.

[0159] The covering area 22225 refers to the area of ​​the second surface 2222b covered by the second insulating member 24. The non-covering area 22226 refers to the area of ​​the second surface 2222b not covered by the second insulating member 24. Covering areas 22225 are provided on both sides of the non-covering area 22226 along the second direction. In other words, the second insulating member 24 covers the areas on both sides of the second surface 2222b along the second direction, and the second insulating member 24 does not cover the middle area of ​​the second surface 2222b along the second direction.

[0160] Both sides of the non-covering area 22226 are connected to the covering area 22225. In comparison, the covering area 22225 is closer to another battery cell 20 adjacent to the battery cell 20. When another battery cell 20 has thermal runaway, along the second direction, the temperature of the area near the two ends of the first insulating member 23 is higher and easier to melt, while the temperature of the first insulating member 23 near the middle is lower and relatively difficult to melt. The covering area 22225 corresponds to the area where the first insulating member 23 is easy to melt, and the non-covering area 22226 corresponds to the area where the first insulating member 23 is relatively difficult to melt. The first insulating member 23 and the second insulating member 24 cooperate to more effectively insulate and isolate the first current collecting member 2222 and the first wall portion 213, which is beneficial to reduce the risk of short circuit of the battery cell 20 and improve the reliability of the battery cell 20.

[0161] Please refer to Figure 4 , Figure 5 , Figure 6 , Figure 7 and Figure 8 In some embodiments, the battery cell 20 includes a plurality of electrode assemblies 22, which are arranged along the second direction, and the second direction intersects the first direction. The body portion 22221 includes a plurality of first connecting portions 22223, which are arranged at intervals along the second direction, and the second connecting portion 22224 connects the plurality of first connecting portions 22223. Each first connecting portion 22223 is connected to a first pole ear 2221 of an electrode assembly 22.

[0162] The main body 22221 may include two first connection parts 22223, three first connection parts 22223, four first connection parts 22223, or more than four first connection parts 22223. The plurality of first connection parts 22223 are arranged at intervals along the second direction. Figure 5 , Figure 6 , Figure 7 and Figure 8 ,exist Figure 5 , Figure 6 , Figure 7 and Figure 8In the illustrated embodiment, the main body 22221 includes two first connection parts 22223 , and the two first connection parts 22223 are arranged at intervals along the second direction. The second connection part 22224 connects the two first connection parts 22223 .

[0163] Each first connection portion 22223 is connected to a first electrode tab 2221 of the electrode assembly 22 , that is, the first connection portions 22223 correspond to the first electrode tabs 2221 one by one.

[0164] Each first connection portion 22223 is connected to the first pole ear 2221 of an electrode assembly 22, and the second connection portion 22224 is connected to multiple first connection portions 22223 to achieve electrical connection between the first current collecting member 2222 and the first pole ears 2221 of multiple electrode assemblies 22. The first pole ears 2221 of multiple electrode assemblies 22 and the first electrode terminal 25 are connected by the first current collecting member 2222, which helps to reduce the difficulty of assembling the first pole ears 2221 and the first electrode terminal 25.

[0165] Please refer to Fig. 9 and Fig.10 , Fig. 9 Schematic diagram of the structure in which the second insulating member 24 is connected to the first current collecting member 2222 provided in some other embodiments of the present application. Fig.10 Exploded views of the second insulating member 24 and the first current collecting member 2222 provided in some other embodiments of the present application. In some embodiments, along the first direction, the second insulating member 24 completely covers the area of ​​the surface of the body portion 22221 facing the first wall portion 213 that is not occupied by the protrusion 22222.

[0166] Along the first direction, the surface of the main body 22221 facing the first wall 213 includes a first area and a second area, wherein the first area is occupied by the protrusion 22222, that is, the protrusion 22222 is arranged in the first area. The second area is the area of ​​the surface of the main body 22221 facing the first wall 213 that is not occupied by the protrusion 22222. The second insulating member 24 completely covers the second area.

[0167] By completely covering the area of ​​the surface of the main body 22221 facing the first wall 213 that is not occupied by the protrusion 22222 with the second insulating member 24, the second insulating member 24 has a better insulation effect, further reducing the risk of short circuit in the battery cell 20, which is beneficial to improving the reliability of the battery cell 20.

[0168] Please refer to Fig. 9 and Fig.10 In some embodiments, the second insulating member 24 is provided with an avoidance hole 241 , and the protrusion 22222 passes through the avoidance hole 241 and is connected to the first electrode terminal 25 .

[0169] The avoidance hole 241 is a through hole that penetrates the second insulating member 24 along the first direction. The shape of the avoidance hole 241 can match the outer contour of the protrusion 22222. For example, when the outer contour of the protrusion 22222 is circular, the avoidance hole 241 is a circular hole. For another example, when the outer contour of the protrusion 22222 is square, the avoidance hole 241 is a square hole.

[0170] The protruding portion 22222 is inserted into the avoiding hole 241 , one end of the protruding portion 22222 is connected to the main body 22221 , and the other end of the protruding portion 22222 is connected to the first electrode terminal 25 .

[0171] By providing the avoidance hole 241 on the second insulating member 24 to avoid the protruding portion 22222, so as to facilitate the connection between the protruding portion 22222 and the first electrode terminal 25, it is helpful to reduce the material consumption of the second insulating member 24. In addition, since the protruding portion 22222 is inserted into the avoidance hole 241, the avoidance hole 241 cooperates with the protruding portion 22222 to limit the second insulating member 24, so that the second insulating member 24 is not easy to deviate or shift, so that the second insulating member 24 can better play an insulating role.

[0172] In some embodiments, the first electrode tab 2221 is connected to a side of the first current collecting member 2222 facing away from the first wall portion 213 .

[0173] When the first electrode tab 2221 is connected to the side of the first current collecting member 2222 away from the first wall 213 , the surface of the first electrode tab 2221 closest to the first wall 213 is connected to the surface of the first current collecting member 2222 away from the first wall 213 .

[0174] When the first pole ear 2221 is connected to the side of the first current collecting member 2222 away from the first wall portion 213, the first current collecting member 2222 is more likely to contact the first wall portion 213 and cause a short circuit than the first pole ear 2221. At this time, the second insulating member 24 is connected to the first current collecting member 2222, and the second insulating member 24 is at least partially located between the first current collecting member 2222 and the first wall portion 213 to insulate and isolate the first current collecting member 2222 from the first wall portion 213. This can enable the second insulating member 24 to exert a better insulation effect, further reduce the risk of short circuit in the battery cell 20, and help to improve the reliability of the battery cell 20.

[0175] In other embodiments, the battery cell 20 includes a first electrode terminal 25, which is disposed on the first wall portion 213. The first electrode lead-out portion 222 includes a first pole tab 2221 and a first current collecting member 2222, wherein the first pole tab 2221 is connected to one end of the main body 221 facing the first wall portion 213 along the first direction, the first pole tab 2221 is connected to a surface of the first current collecting member 2222 facing the first wall portion 213, and the first current collecting member 2222 is connected to the first electrode terminal 25. The second insulating member 24 is connected to the surface of the first pole tab 2221 closest to the first wall portion 213.

[0176] The first electrode tab 2221 may be bent around the first current collecting member 2222 so as to be connected to a surface of the first current collecting member 2222 facing the first wall portion 213. At this time, a portion of the first electrode tab is located between the first current collecting member 2222 and the first wall portion 213 along the first direction.

[0177] The first electrode tab 2221 has a surface closest to the first wall 213, and along the first direction, the surface is located between the first current collecting member 2222 and the first wall 213. The second insulating member is connected to the surface of the first electrode tab 2221 closest to the first wall 213 to insulate the first electrode tab 2221 from the first wall 213.

[0178] The first pole lug 2221 is connected to the first electrode terminal 25 through the first current collecting member 2222, but the first pole lug 2221 is connected to the surface of the first current collecting member 2222 facing the first wall portion 213. The first pole lug 2221 is more likely to contact the first wall portion 213 and cause a short circuit than the first current collecting member 2222. At this time, the second insulating member 24 is connected to the surface of the first pole lug 2221 closest to the first wall portion 213 to insulate and isolate the first pole lug 2221 from the first wall portion 213, which can enable the second insulating member 24 to exert a better insulation effect, further reduce the risk of short circuit in the battery cell 20, and help to improve the reliability of the battery cell 20.

[0179] Please refer to Fig.11 , Fig.11 The present application also provides an exploded view of a battery cell 20 in some embodiments. In some embodiments, the battery cell 20 includes a first electrode terminal 25, and the first electrode terminal 25 is disposed on the first wall portion 213. The first electrode lead-out portion 222 includes a first pole ear 2221, and the first pole ear 2221 is connected to the first electrode terminal 25. The second insulating member 24 is connected to the first pole ear 2221, and along the first direction, the second insulating member 24 is at least partially located between the first pole ear 2221 and the first wall portion 213.

[0180] The first electrode tab 2221 is a positive electrode tab or a negative electrode tab and is directly connected to the first electrode terminal 25 to guide the electric energy of the electrode assembly 22 to the first electrode terminal 25 or receive the electric energy introduced from the first electrode terminal 25 .

[0181] The second insulating member 24 is connected to the first electrode tab 2221 , and is partially or entirely located between the first electrode tab 2221 and the first wall portion 213 along the first direction to insulate and isolate the first electrode tab 2221 from the first wall portion 213 .

[0182] The first pole ear 2221 is directly connected to the first electrode terminal 25, and the second insulating member 24 is connected to the first pole ear 2221, and the second insulating member 24 is at least partially located between the first pole ear 2221 and the first wall portion 213 to insulate and isolate the first pole ear 2221 from the first wall portion 213, so that the second insulating member 24 has a better insulation effect, further reducing the risk of short circuit in the battery cell 20, which is beneficial to improving the reliability of the battery cell 20.

[0183] In some embodiments, along the first direction, a projection of the second insulating member 24 does not overlap with a projection of the first electrode terminal 25 .

[0184] “Along the first direction, the projection of the second insulating member 24 does not overlap with the projection of the first electrode terminal 25 ” can also be understood as the second insulating member 24 does not cover the first electrode terminal 25 , so as to facilitate the connection between the first electrode tab 2221 and the first electrode terminal 25 .

[0185] By making the projection of the second insulating member 24 along the first direction non-overlap with the projection of the first electrode terminal 25 along the first direction, the risk of the second insulating member 24 interfering with the connection between the first electrode terminal 25 and the first electrode tab 2221 is reduced, thereby facilitating the connection between the first electrode terminal 25 and the first electrode tab 2221 .

[0186] Please refer to Fig.11 In some embodiments, the second insulating member 24 is provided with an avoidance hole 241 , and the first electrode terminal 25 passes through the avoidance hole 241 and is connected to the first electrode tab 2221 .

[0187] The avoidance hole 241 is a through hole that penetrates the second insulating member 24 along the first direction. The shape of the avoidance hole 241 can match the outer contour of the first electrode terminal 25. For example, when the outer contour of the first electrode terminal 25 is circular, the avoidance hole 241 is a circular hole. For another example, when the outer contour of the first electrode terminal 25 is square, the avoidance hole 241 is a square hole.

[0188] The first electrode terminal 25 is inserted into the avoidance hole 241 , and one end of the first electrode terminal 25 is connected to the first electrode tab 2221 .

[0189] By providing the avoidance hole 241 on the second insulating member 24 to avoid the first electrode terminal 25, so as to facilitate the connection between the first electrode tab 2221 and the first electrode terminal 25, it is helpful to reduce the material consumption of the second insulating member 24. In addition, since the first electrode terminal 25 is inserted into the avoidance hole 241, the avoidance hole 241 cooperates with the first electrode terminal 25 to limit the second insulating member 24, so that the second insulating member 24 is not easy to deviate or shift, so that the second insulating member 24 can better play an insulating role.

[0190] In other embodiments, the second insulating member 24 may also be disposed on the first wall portion 213. For example, a receiving hole is disposed on the first insulating member 23, and the second insulating member 24 is connected to the first wall portion 213 and received in the receiving hole. When another battery cell 20 adjacent to the battery cell 20 undergoes thermal runaway, causing the first insulating member 23 of the battery cell 20 to melt, the second insulating member 24 can still play a role in insulating and isolating the first electrode lead-out portion 222 and the first wall portion 213 to a certain extent, thereby reducing the risk of a short circuit caused by the first electrode lead-out portion 222 contacting the first wall portion 213.

[0191] In some other embodiments, along the first direction, the second insulating member 24 is disposed between the first insulating member 23 and the first wall portion 213. For example, along the first direction, the first insulating member 23 includes an insulating body and a clamping portion protruding from the insulating body, the clamping portion is clamped to the first wall portion 213, and the insulating body is spaced from the first wall portion 213. In this case, the second insulating member 24 can be disposed between the first insulating member 23 (insulating body) and the first wall portion 213.

[0192] In some embodiments, the second insulating member 24 is bonded to the first electrode lead-out portion 222 .

[0193] In the embodiment where the first electrode lead portion 222 includes the first electrode tab 2221 and the first current collecting member 2222, the second insulating member 24 is bonded to the first current collecting member 2222. In the embodiment where the first electrode lead portion 222 includes only the first electrode tab 2221, the second insulating member 24 is bonded to the first electrode tab 2221.

[0194] By bonding the second insulating member 24 to the first electrode lead-out portion 222 , the second insulating member 24 is connected to the first electrode lead-out portion 222 simply and conveniently, which helps to limit the position of the second insulating member 24 so that the second insulating member 24 can stably exert the insulating effect.

[0195] In some other embodiments, the second insulating member 24 covers the first electrode lead-out portion 222 .

[0196] In the embodiment where the first electrode lead-out portion 222 includes the first electrode tab 2221 and the first current collecting member 2222, the second insulating member 24 may only cover the first electrode lead-out portion 222, or may cover the first electrode tab 2221 and the first electrode lead-out portion 222. In the embodiment where the first electrode lead-out portion 222 only includes the first electrode tab 2221, the second insulating member 24 covers the first electrode tab 2221.

[0197] By covering the first electrode lead-out portion 222 with the second insulating member 24, on the one hand, the first electrode lead-out portion 222 can be well covered, thereby isolating the first electrode lead-out portion 222 from the first wall portion 213. On the other hand, when the second insulating member 24 is covered with the first electrode lead-out portion 222, the second insulating member 24 is not easy to deviate or shift relative to the first electrode lead-out portion 222, so that the second insulating member 24 can better play an insulating role.

[0198] In some embodiments, the second insulating member 24 is an insulating film connected to the first electrode lead-out portion 222 .

[0199] Optionally, the second insulating member 24 is a PI film (Polyimide Film) connected to the first electrode lead-out portion 222 .

[0200] The second insulating member 24 is an insulating film, which can effectively insulate and isolate the first electrode lead-out portion 222 and the first wall portion 213 without occupying too much space inside the housing 21 , so that the battery cell 20 can still have a high energy density.

[0201] In some embodiments, the material damage temperature of the second insulating member 24 is greater than or equal to 300° C.

[0202] When another battery cell 20 adjacent to the battery cell 20 experiences thermal runaway, the temperature inside the battery cell 20 may rise to 200° C. However, the material damage temperature of the second insulating member 24 is greater than or equal to 300° C. Therefore, when another battery cell 20 adjacent to the battery cell 20 experiences thermal runaway, it is not easy to cause the second insulating member 24 to melt, so that the second insulating member 24 can play an insulating isolation role and reduce the risk of short circuit of the battery cell 20.

[0203] Optionally, the material of the second insulating member 24 includes at least one of polyimide, polyetheretherketone, and polytetrafluoroethylene.

[0204] Polyimide, polyetheretherketone, and polytetrafluoroethylene have good high temperature resistance and good insulation effect. They can insulate the first electrode lead-out portion 222 from the first wall portion 213 when the temperature is higher than 200°C, reducing the risk of short circuit of the battery cell 20, thereby improving the reliability of the battery cell 20.

[0205] In some embodiments, the electrode assembly 22 includes a second electrode lead portion 223, and the second electrode lead portion 223 is connected to the main body 221. The first electrode lead portion 222 and the second electrode lead portion 223 can be located at the same end of the main body 221, or at both ends of the main body 221.

[0206] When the first electrode lead-out portion 222 and the second electrode lead-out portion 223 are located at the same end of the main body portion 221, the first insulating member 23 can also insulate and isolate the second electrode lead-out portion 223 from the first wall portion 213. The battery cell 20 further includes a third insulating member 26. Along the first direction, at least a portion of the third insulating member 26 is disposed between the second electrode lead-out portion 223 and the first wall portion 213. The material damage temperature of the third insulating member 26 is greater than the material damage temperature of the first insulating member 23. The third insulating member 26 is configured to insulate and isolate the second electrode lead-out portion 223 from the first wall portion 213 when the first insulating member 23 melts.

[0207] The battery cell 20 includes a second electrode terminal 27, which is disposed on the first wall portion 213. In some embodiments, the second electrode lead-out portion 223 may include a second pole tab 2231 and a second current collecting member 2232, the second pole tab 2231 having a polarity opposite to that of the first pole tab 2221, the second pole tab 2231 being connected to one end of the main body 221 facing the first wall portion 213 along the first direction, and the second current collecting member 2232 connecting the second electrode terminal 27 and the second pole tab 2231. The third insulating member 26 may be connected to the second current collecting member 2232, and the specific manner in which the third insulating member 26 is connected to the second current collecting member 2232 may refer to the manner in which the second insulating member 24 is connected to the first current collecting member 2222, which will not be described in detail herein. In other embodiments, the second electrode lead-out portion 223 includes a second pole tab 2231, the second pole tab 2231 having a polarity opposite to that of the first pole tab 2221, and the second pole tab 2231 being connected to the second electrode terminal 27. The third insulating member 26 can be connected to the second pole tab 2231 . The specific method of connecting the third insulating member 26 to the second pole tab 2231 can refer to the connection method of connecting the second insulating member 24 to the first pole tab 2221 , which will not be repeated here.

[0208] When the first electrode lead-out portion 222 and the second electrode lead-out portion 223 are located at both ends of the main body 221, the battery cell 20 further includes a third insulating member 26 and a fourth insulating member, and the housing 21 includes a second wall portion, which is arranged opposite to the first wall portion 213. The second electrode lead-out portion 223 is arranged at one end of the main body 221 facing the second wall portion along the first direction. Along the first direction, the fourth insulating member is arranged on the surface of the second wall portion facing the electrode assembly 22, and the fourth insulating member is used to insulate and isolate the second electrode lead-out portion 223 and the second wall portion. Along the first direction, at least a portion of the third insulating member 26 is arranged between the second electrode lead-out portion 223 and the second wall portion, and the material damage temperature of the third insulating member 26 is greater than the material damage temperature of the fourth insulating member. The third insulating member 26 is configured to insulate and isolate the second electrode lead-out portion 223 and the second wall portion when the fourth insulating member melts.

[0209] The battery cell 20 includes a second electrode terminal 27, which is disposed on the second wall portion. In some embodiments, the second electrode lead-out portion 223 may include a second pole tab 2231 and a second current collecting member 2232, the second pole tab 2231 having a polarity opposite to that of the first pole tab 2221, the second pole tab 2231 being connected to one end of the main body 221 facing the second wall portion along the first direction, and the second current collecting member 2232 connecting the second electrode terminal 27 and the second pole tab 2231. The third insulating member 26 may be connected to the second current collecting member 2232, and the specific manner in which the third insulating member 26 is connected to the second current collecting member 2232 may refer to the manner in which the second insulating member 24 is connected to the first current collecting member 2222, which will not be described in detail herein. In other embodiments, the second electrode lead-out portion 223 includes a second pole tab 2231, the second pole tab 2231 having a polarity opposite to that of the first pole tab 2221, and the second pole tab 2231 being connected to the second electrode terminal 27. The third insulating member 26 can be connected to the second pole tab 2231 . The specific method of connecting the third insulating member 26 to the second pole tab 2231 can refer to the connection method of connecting the second insulating member 24 to the first pole tab 2221 , which will not be repeated here.

[0210] In some embodiments, the third insulating member 26 is bonded to the second electrode lead-out portion 223 .

[0211] In the embodiment where the second electrode lead-out portion 223 includes the second electrode tab 2231 and the second current collecting member 2232, the third insulating member 26 is bonded to the second current collecting member 2232. In the embodiment where the second electrode lead-out portion 223 includes only the second electrode tab 2231, the third insulating member 26 is bonded to the second electrode tab 2231.

[0212] By bonding the third insulating member 26 to the second electrode lead-out portion 223 , the third insulating member 26 is connected to the second electrode lead-out portion 223 in a simple and convenient manner, which is beneficial for limiting the position of the third insulating member 26 so that the third insulating member 26 can stably exert its insulating effect.

[0213] In some other embodiments, the third insulating member 26 covers the second electrode lead-out portion 223 .

[0214] In the embodiment where the second electrode lead-out portion 223 includes the second electrode tab 2231 and the second current collecting member 2232, the third insulating member 26 may only cover the second electrode lead-out portion 223, or may cover the second electrode tab 2231 and the second electrode lead-out portion 223. In the embodiment where the second electrode lead-out portion 223 only includes the second electrode tab 2231, the third insulating member 26 covers the second electrode tab 2231.

[0215] By covering the second electrode lead-out portion 223 with the third insulating member 26, on the one hand, the second electrode lead-out portion 223 can be well covered, thereby isolating the second electrode lead-out portion 223 from the first wall portion 213 or the second wall portion. On the other hand, when the third insulating member 26 is covered on the second electrode lead-out portion 223, the third insulating member 26 is not likely to deviate or shift relative to the second electrode lead-out portion 223, so that the third insulating member 26 can better play an insulating role.

[0216] In some embodiments, the third insulating member 26 is an insulating film connected to the second electrode lead-out portion 223 .

[0217] Optionally, the third insulating member 26 is a PI film (Polyimide Film) connected to the second electrode lead-out portion 223 .

[0218] The third insulating member 26 is an insulating film, which can effectively insulate and isolate the second electrode lead-out portion 223 and the first wall portion 213 or the second electrode lead-out portion 223 and the second wall portion without occupying too much space inside the housing 21, so that the battery cell 20 can still have a high energy density.

[0219] In some embodiments, the material damage temperature of the third insulating member 26 is greater than or equal to 300° C.

[0220] When another battery cell 20 adjacent to the battery cell 20 experiences thermal runaway, the temperature inside the battery cell 20 may rise to 200° C. However, the material damage temperature of the third insulating member 26 is greater than or equal to 300° C. Therefore, when another battery cell 20 adjacent to the battery cell 20 experiences thermal runaway, it is not easy to cause the third insulating member 26 to melt, so that the third insulating member 26 can play an insulating isolation role and reduce the risk of short circuit of the battery cell 20.

[0221] Optionally, the material of the third insulating member 26 includes at least one of polyimide, polyetheretherketone, and polytetrafluoroethylene.

[0222] Polyimide, polyetheretherketone, and polytetrafluoroethylene have good high temperature resistance and good insulation effect. They can insulate the second electrode lead-out portion 223 from the first wall portion 213 or the second electrode lead-out portion 223 from the second wall portion when the temperature is higher than 200°C, thereby reducing the risk of short circuit of the battery cell 20 and improving the reliability of the battery cell 20.

[0223] In some embodiments, the positive electrode material of the battery cell 20 includes a lithium-containing phosphate.

[0224] The positive electrode material includes a battery cell 20 containing lithium phosphate. When thermal runaway occurs, a large amount of heat will be generated, which may easily cause the first insulating member 23 of the battery cell 20 and another adjacent battery cell 20 to melt. By arranging a second insulating member 24 in the battery cell 20, it is more conducive to reducing the risk of short circuit caused by contact between the first electrode lead-out portion 222 and the first wall portion 213. That is, the effect of arranging the second insulating member 24 in the battery cell 20 containing lithium phosphate is better.

[0225] Optionally, the lithium-containing phosphate includes at least one of lithium iron phosphate, a composite material of lithium iron phosphate and carbon, lithium manganese phosphate, a composite material of lithium manganese phosphate and carbon, lithium iron manganese phosphate, and a composite material of lithium iron manganese phosphate and carbon.

[0226] The embodiment of the present application further provides a battery 100 , and the battery 100 includes the above-mentioned battery cell 20 .

[0227] The embodiment of the present application further provides an electrical device, which includes the above-mentioned battery cell 20.

[0228] According to some embodiments of this application, please refer to Figures 3 to 10 .

[0229] The embodiment of the present application provides a battery cell 20, which includes a housing 21, an electrode assembly 22, a first insulating member 23, and a second insulating member 24. The housing 21 has a first wall portion 213, and the electrode assembly 22 is accommodated in the housing 21. The electrode assembly 22 includes a first electrode lead-out portion 222 and a main body portion 221, and the first electrode lead-out portion 222 is arranged at one end of the main body portion 221 facing the first wall portion 213 along the first direction. Along the first direction, the first insulating member 23 is arranged on the surface of the first wall portion 213 facing the electrode assembly 22, and the first insulating member 23 is used to insulate and isolate the first electrode lead-out portion 222 and the first wall portion 213. Along the first direction, at least a portion of the second insulating member 24 is arranged between the first electrode lead-out portion 222 and the first wall portion 213, and the material damage temperature of the second insulating member 24 is greater than the material damage temperature of the first insulating member 23. The second insulating member 24 is configured to insulate and isolate the first electrode lead-out portion 222 and the first wall portion 213 when the first insulating member 23 melts. The battery cell 20 is provided with a first insulating member 23 and a second insulating member 24. In normal use, the first insulating member 23 and the second insulating member 24 can both insulate and isolate the first electrode lead-out portion 222 and the first wall portion 213, reducing the risk of the first electrode lead-out portion 222 contacting the first wall portion 213 and causing a short circuit. Since the material damage temperature of the second insulating member 24 is greater than the material damage temperature of the first insulating member 23, when another battery cell 20 adjacent to the battery cell 20 undergoes thermal runaway, causing the first insulating member 23 of the battery cell 20 to melt, the second insulating member 24 can still play a role in insulating and isolating the first electrode lead-out portion 222 and the first wall portion 213 to a certain extent, reducing the risk of the first electrode lead-out portion 222 contacting the first wall portion 213 and causing a short circuit. In this way, even if another battery cell 20 adjacent to the battery cell 20 undergoes thermal runaway, it is not easy to cause the battery cell 20 to short-circuit and continue to cause thermal runaway, which is conducive to limiting heat diffusion and improving the reliability of the battery cell 20.

[0230] The battery cell 20 includes a first electrode terminal 25, which is disposed on the first wall portion 213. The first electrode lead-out portion 222 includes a first electrode tab 2221 and a first current collecting member 2222, wherein the first electrode tab 2221 is connected to one end of the main body 221 facing the first wall portion 213 along the first direction, and the first current collecting member 2222 connects the first electrode terminal 25 and the first electrode tab 2221. The second insulating member 24 is connected to the first current collecting member 2222, and along the first direction, the second insulating member 24 is at least partially located between the first current collecting member 2222 and the first wall portion 213. The first pole ear 2221 is connected to the first electrode terminal 25 through the first current collecting member 2222. The first current collecting member 2222 is more likely to contact the first wall portion 213 and cause a short circuit than the first pole ear 2221. Therefore, the second insulating member 24 is connected to the first current collecting member 2222, and the second insulating member 24 is at least partially located between the first current collecting member 2222 and the first wall portion 213 to insulate and isolate the first current collecting member 2222 from the first wall portion 213, so that the second insulating member 24 has a better insulation effect, further reducing the risk of short circuit in the battery cell 20, which is beneficial to improving the reliability of the battery cell 20.

[0231] In some embodiments, the first current collecting member 2222 includes a body portion 22221 and a protrusion 22222, the protrusion 22222 protrudes from the body portion 22221 along the first direction, the body portion 22221 is connected to the first electrode tab 2221, and the protrusion 22222 is connected to the first electrode terminal 25. In the first direction, the body portion 22221 has a first surface 2222a closest to the first wall portion 213, and the second insulating member 24 covers at least a portion of the first surface 2222a. The first surface 2222a is the surface of the main body 22221 that is closest to the first wall portion 213, that is, the first surface 2222a is the surface on the first current collecting member 2222 that is most likely to contact the first wall portion 213 and cause a short circuit. By making the second insulating member 24 cover at least a portion of the first surface 2222a so as to insulate and isolate the first current collecting member 2222 from the first wall portion 213, the second insulating member 24 has a better insulation effect, which is beneficial to reducing the risk of short circuit in the battery cell 20 and improving the reliability of the battery cell 20.

[0232] Along the first direction, the body portion 22221 includes a first connection portion 22223 and a second connection portion 22224, the second connection portion 22224 is connected to the first connection portion 22223, and the first pole ear 2221 is connected to the first connection portion 22223. Along the first direction, the surface of the first connection portion 22223 facing the first wall portion 213 is the first surface 2222a, the second connection portion 22224 has a second surface 2222b facing the first wall portion 213, the first surface 2222a is closer to the first wall portion 213 than the second surface 2222b, and the protrusion 22222 protrudes from the second surface 2222b. The second insulating member 24 covers at least a portion of the second surface 2222b. The body portion 22221 includes a first surface 2222a and a second surface 2222b, wherein the first surface 2222a is the surface closest to the first wall portion 213, and the distance between the second surface 2222b and the first wall portion 213 is greater than the distance between the first surface 2222a and the first wall portion 213. Since both the first surface 2222a and the second surface 2222b have the risk of short circuit due to contact with the first wall portion 213, the second insulating member 24 is made to cover at least a portion of the first surface 2222a and at least a portion of the second surface 2222b, so as to better insulate and isolate the first current collecting member 2222 from the first wall portion 213, so that the second insulating member 24 has a better insulation effect, which is conducive to further reducing the risk of short circuit of the battery cell 20 and further improving the reliability of the battery cell 20.

[0233] The battery cell 20 includes a plurality of electrode assemblies 22, and the plurality of electrode assemblies 22 are arranged along a second direction, and the second direction intersects with the first direction. The second surface 2222b includes a covering area 22225 covered by the second insulating member 24 and a non-covering area 22226 not covered by the second insulating member 24. Along the second direction, both sides of the non-covering area 22226 are connected to the covering area 22225, and the protrusion 22222 is arranged in the non-covering area 22226. Both sides of the non-covering area 22226 are connected to the covering area 22225, and in comparison, the covering area 22225 is closer to another battery cell 20 adjacent to the battery cell 20. When another battery cell 20 experiences thermal runaway, along the second direction, the temperature of the areas near the two ends of the first insulating member 23 is higher and more easily melted, while the temperature of the first insulating member 23 near the middle is lower and relatively less likely to melt. The covering area 22225 corresponds to the area where the first insulating member 23 is easily melted, and the non-covering area 22226 corresponds to the area where the first insulating member 23 is relatively less likely to melt. The first insulating member 23 and the second insulating member 24 cooperate to more effectively insulate and isolate the first current collecting member 2222 and the first wall portion 213, which is beneficial to reducing the risk of short circuit of the battery cell 20 and improving the reliability of the battery cell 20.

[0234] In other embodiments, the battery cell 20 includes a first electrode terminal 25, and the first electrode terminal 25 is disposed on the first wall portion 213. The first electrode lead-out portion 222 includes a first pole ear 2221, and the first pole ear 2221 is connected to the first electrode terminal 25. The second insulating member 24 is connected to the first pole ear 2221, and along the first direction, the second insulating member 24 is at least partially located between the first pole ear 2221 and the first wall portion 213. The first pole ear 2221 is directly connected to the first electrode terminal 25, and the second insulating member 24 is connected to the first pole ear 2221, and the second insulating member 24 is at least partially located between the first pole ear 2221 and the first wall portion 213, so as to insulate and isolate the first pole ear 2221 from the first wall portion 213, so that the second insulating member 24 has a better insulation effect, further reducing the risk of short circuit of the battery cell 20, which is conducive to improving the reliability of the battery cell 20.

[0235] The first insulating member 23 can also insulate and isolate the second electrode lead-out portion 223 and the first wall portion 213. The battery cell 20 further includes a third insulating member 26. Along the first direction, at least a portion of the third insulating member 26 is disposed between the second electrode lead-out portion 223 and the first wall portion 213. The material damage temperature of the third insulating member 26 is greater than the material damage temperature of the first insulating member 23. The third insulating member 26 is configured to insulate and isolate the second electrode lead-out portion 223 and the first wall portion 213 when the first insulating member 23 melts.

[0236] The battery cell 20 includes a second electrode terminal 27, and the second electrode terminal 27 is disposed on the first wall portion 213. In some embodiments, the second electrode lead portion 223 may include a second pole tab 2231 and a second current collecting member 2232, the second pole tab 2231 has a polarity opposite to that of the first pole tab 2221, the second pole tab 2231 is connected to one end of the main body 221 facing the first wall portion 213 along the first direction, and the second current collecting member 2232 connects the second electrode terminal 27 and the second pole tab 2231. The third insulating member 26 may be connected to the second current collecting member 2232, and the specific manner in which the third insulating member 26 is connected to the second current collecting member 2232 may refer to the aforementioned manner in which the second insulating member 24 is connected to the first current collecting member 2222, and will not be repeated here.

[0237] The second insulating member 24 is an insulating film bonded to the first current collecting member 2222. By bonding the second insulating member 24 to the first current collecting member 2222, it is simple and convenient to connect the second insulating member 24 to the first current collecting member 2222, which is conducive to limiting the position of the second insulating member 24, so that the second insulating member 24 can stably exert the insulating effect. The second insulating member 24 is an insulating film, which can effectively insulate and isolate the first current collecting member 2222 and the first wall portion 213, and will not occupy too much space inside the housing 21, so that the battery cell 20 can still have a high energy density.

[0238] The above description is only the preferred embodiment of the present application and is not intended to limit the present application. For those skilled in the art, the present application may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application shall be included in the protection scope of the present application.

Claims

1. A battery cell, characterized in that: include: A housing having a first wall portion; an electrode assembly, contained in the housing, the electrode assembly comprising a first electrode lead-out portion and a main body portion, the first electrode lead-out portion being arranged at one end of the main body portion facing the first wall portion along a first direction; A first insulating member, along the first direction, the first insulating member is arranged on a surface of the first wall portion facing the electrode assembly, and the first insulating member is used for insulating and isolating the first electrode lead portion and the first wall portion; A second insulating member, along the first direction, at least a portion of the second insulating member is disposed between the first electrode lead-out portion and the first wall portion, and a material damage temperature of the second insulating member is greater than a material damage temperature of the first insulating member.

2. The battery cell according to claim 1, characterized in that: The second insulating member is connected to the first electrode lead-out portion.

3. The battery cell according to claim 2, characterized in that: The battery cell includes a first electrode terminal, and the first electrode terminal is disposed on the first wall portion; The first electrode lead-out portion includes a first electrode tab and a first current collecting member, the first electrode tab is connected to one end of the main body portion facing the first wall portion along a first direction, and the first current collecting member connects the first electrode terminal and the first electrode tab; The second insulating member is connected to the first current collecting member, and along the first direction, the second insulating member is at least partially located between the first current collecting member and the first wall portion.

4. The battery cell according to claim 3, characterized in that: The first current collecting member includes a body portion and a protruding portion, the protruding portion protrudes from the body portion along the first direction, the body portion is connected to the first electrode tab, and the protruding portion is connected to the first electrode terminal; Wherein, along the first direction, the main body has a first surface closest to the first wall portion, and the second insulating member covers at least a portion of the first surface.

5. The battery cell according to claim 4, characterized in that: Along the first direction, the main body portion includes a first connecting portion and a second connecting portion, the second connecting portion is connected to the first connecting portion, the first pole ear is connected to the first connecting portion, and along the first direction, the surface of the first connecting portion facing the first wall portion is the first surface, and the second connecting portion has a second surface facing the first wall portion, the first surface is closer to the first wall portion than the second surface, the protrusion protrudes from the second surface, and the second insulating member covers at least a portion of the second surface.

6. The battery cell according to claim 5, characterized in that: The battery cell includes a plurality of electrode assemblies, and the plurality of electrode assemblies are arranged along a second direction, and the second direction intersects with the first direction; The second surface includes a covering area covered by the second insulating member and a non-covering area not covered by the second insulating member. Along the second direction, both sides of the non-covering area are connected to the covering area, and the protrusion is arranged in the non-covering area.

7. The battery cell according to claim 5, characterized in that: The battery cell includes a plurality of electrode assemblies, and the plurality of electrode assemblies are arranged along a second direction, and the second direction intersects with the first direction; The main body includes a plurality of first connection portions, the plurality of first connection portions are arranged at intervals along the second direction, the second connection portion connects the plurality of first connection portions, and each of the first connection portions is connected to the first electrode tab of one of the electrode assemblies.

8. The battery cell according to claim 4, characterized in that: Along the first direction, the second insulating member completely covers an area of ​​the surface of the body portion facing the first wall portion that is not occupied by the protruding portion.

9. The battery cell according to claim 4, characterized in that: The second insulating member is provided with an escape hole, and the protrusion passes through the escape hole and is connected to the first electrode terminal.

10. The battery cell according to claim 3, characterized in that: The first electrode tab is connected to a side of the first current collecting member facing away from the first wall portion.

11. The battery cell according to claim 2, characterized in that: The battery cell includes a first electrode terminal, and the first electrode terminal is disposed on the first wall portion; The first electrode lead-out portion comprises a first electrode tab and a first current collecting member, the first electrode tab is connected to one end of the main body portion facing the first wall portion along the first direction, the first electrode tab is connected to a surface of the first current collecting member facing the first wall portion, and the first current collecting member is connected to the first electrode terminal; Wherein, the second insulating member is connected to the surface of the first electrode tab that is closest to the first wall portion.

12. The battery cell according to claim 2, characterized in that: The battery cell includes a first electrode terminal, and the first electrode terminal is disposed on the first wall portion; The first electrode lead-out portion includes a first electrode tab, and the first electrode tab is connected to the first electrode terminal; The second insulating member is connected to the first pole lug, and along the first direction, the second insulating member is at least partially located between the first pole lug and the first wall portion.

13. The battery cell according to claim 12, characterized in that: Along the first direction, a projection of the second insulating member does not overlap with a projection of the first electrode terminal.

14. The battery cell according to claim 12, characterized in that: The second insulating member is provided with an avoidance hole, and the first electrode terminal passes through the avoidance hole and is connected with the first electrode tab.

15. The battery cell according to any one of claims 2 to 14, characterized in that: The second insulating member is bonded to the first electrode lead-out portion.

16. The battery cell according to any one of claims 2 to 14, characterized in that: The second insulating member covers the first electrode lead-out portion.

17. The battery cell according to any one of claims 2 to 14, characterized in that: The second insulating member is an insulating film connected to the first electrode lead portion.

18. The battery cell according to any one of claims 1 to 14, characterized in that: The material damage temperature of the second insulating member is greater than or equal to 300° C.

19. The battery cell according to claim 18, characterized in that: The material of the second insulating member includes at least one of polyimide, polyetheretherketone, and polytetrafluoroethylene.

20. The battery cell according to any one of claims 1 to 14, characterized in that: The positive electrode material of the battery cell includes lithium-containing phosphate.

21. The battery cell according to claim 20, characterized in that: The lithium-containing phosphate includes at least one of lithium iron phosphate, a composite material of lithium iron phosphate and carbon, lithium manganese phosphate, a composite material of lithium manganese phosphate and carbon, lithium iron manganese phosphate, and a composite material of lithium iron manganese phosphate and carbon.

22. A battery, characterized in that: Comprising a battery cell according to any one of claims 1-21.

23. An electrical equipment, characterized in that: Comprising a battery cell according to any one of claims 1-21.

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