Battery cell, battery, and electric device

Abstract

A battery cell (20), a battery, and an electric device. The battery cell (20) comprises a casing (21), electrode assemblies (22), first insulating members (23), and second insulating members (24); the casing (21) has a first wall portion (213); the electrode assemblies (22) are accommodated in the casing (21); the electrode assemblies (22) comprise a first electrode lead-out portion (222) and main body portions (221); the first electrode lead-out portion (222) is provided at the end of the main body portions (221) facing the first wall portion (213) in a first direction; in the first direction, the first insulating members (23) are provided on the surface of the first wall portion (213) facing the electrode assemblies (22), and are used for insulating the first electrode lead-out portion (222) from the first wall portion (213); and in the first direction, at least part of the second insulating members (24) is provided between the first electrode lead-out portion (222) and the first wall portion (213), the material damage temperature of the second insulating members (24) is greater than that of the first insulating members (23), and the second insulating members (24) can insulate the first electrode lead-out portion (222) from the first wall portion (213) when the first insulating members (23) have melted. When the first insulating members (23) have melted, the second insulating members (24) can still exert the insulation effect, thereby reducing the risk of short circuit and improving the reliability of the battery.

Description

Battery cells, batteries and electrical equipment Technical Field

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

[0002] Batteries are widely used in new energy applications, such as electric vehicles and new energy vehicles. These have become a new trend in the automotive industry. The development of battery technology requires consideration of multiple design factors, including performance parameters such as battery life, energy density, discharge capacity, and charge / discharge rate. Furthermore, battery reliability must be considered. However, current battery reliability is relatively poor.

[0003] Summary of the Invention

[0004] 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.

[0005] 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, wherein the shell has a first wall portion; the electrode assembly is accommodated in the shell, and the electrode assembly comprises a first electrode lead-out portion and a main body portion, the first electrode lead-out portion is 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.

[0006] In the above technical solution, the battery cell is provided with a first insulating member and a second insulating member. During normal use, the first insulating member and the second insulating member can both insulate and isolate the first electrode lead portion from the first wall portion, reducing the risk of a short circuit caused by the first electrode lead portion contacting the first wall portion. 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 portion from the first wall portion to a certain extent, reducing the risk of a short circuit caused by the first electrode lead portion contacting the first wall portion. In this way, even if another battery cell adjacent to the battery cell experiences thermal runaway, it is not easy to cause a short circuit in the battery cell and continue to cause thermal runaway, which is conducive to limiting heat diffusion and improving the reliability of the battery cell.

[0007] As an optional technical solution of the embodiment of the present application, the second insulating member is connected to the first electrode lead-out portion.

[0008] 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 disposed on the surface of the first wall portion facing the electrode assembly, connecting the second insulating member to the first electrode lead-out portion is more convenient and less likely to interfere with the first insulating member. On the other hand, connecting the second insulating member to the first electrode lead-out portion restricts the relative position of the second insulating member and the first electrode lead-out portion, allowing the second insulating member to be stably positioned between the first electrode lead-out portion and the first wall portion, thereby insulating and isolating the first electrode lead-out portion from the first wall portion.

[0009] 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 electrode tab and a first current collecting member, the first electrode tab is connected to one end of the main body facing the first wall portion along the first direction, and the first current collecting member connects the first electrode terminal and the first electrode tab; 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.

[0010] 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.

[0011] 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 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.

[0012] 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.

[0013] 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.

[0014] 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. Because both the first surface and the second surface have the risk of short circuiting due to contact with the first wall, the second insulating member is configured to cover at least a portion of the first surface and at least a portion of the second surface to better insulate the first current collecting member from the first wall. This improves the insulation effect of the second insulating member, further reducing the risk of short circuiting in the battery cells and further improving the reliability of the battery cells.

[0015] 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.

[0016] In the above technical solution, both sides of the uncovered area are connected to covered areas. In comparison, the covered areas are closer to another battery cell adjacent to the battery cell. When the other battery cell experiences thermal runaway, along the second direction, the areas near the ends of the first insulating member have a higher temperature and are more likely to melt, while the areas near the middle of the first insulating member have a lower temperature and are relatively less likely to melt. The covered areas correspond to the areas of the first insulating member that are easily melted, and the uncovered areas correspond to the areas of the first insulating member that are relatively less likely to melt. The first and second insulating members work together to more effectively insulate and isolate the first current collecting member from the first wall, which helps reduce the risk of short circuits in the battery cells and improves the reliability of the battery cells.

[0017] 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 parts, and the plurality of first connecting parts are arranged at intervals along the second direction, and the second connecting part connects the plurality of first connecting parts, and each first connecting part is connected to the first pole ear of one of the electrode assemblies.

[0018] In the above technical solution, each first connecting portion is connected to the first pole tab 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 member and the first pole tabs of multiple electrode assemblies 22. The first pole tabs of multiple electrode assemblies and the first electrode terminal are connected through the first current collecting member, which is conducive to reducing the difficulty of assembly between the first pole tab and the first electrode terminal.

[0019] As an optional technical solution of the embodiment of the present application, along the first direction, the second insulating member completely covers the area of ​​the surface of the main body facing the first wall portion that is not occupied by the protrusion.

[0020] 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.

[0021] 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.

[0022] In the above technical solution, a clearance hole is provided on the second insulating member to allow for the protrusion to pass through, facilitating connection between the protrusion and the first electrode terminal, thereby reducing material consumption for the second insulating member. Furthermore, since the protrusion is inserted into the clearance hole, the clearance hole and the protrusion cooperate to limit the second insulating member, preventing it from deviating or shifting, thereby enabling it to better perform its insulating function.

[0023] 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 facing away from the first wall portion.

[0024] In the above technical solution, when the first electrode tab is connected to the side of the first current collecting member facing away from the first wall portion, the first current collecting member is more likely to contact the first wall portion than the first electrode tab and cause a short circuit. 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 the first current collecting member from the first wall portion. This can enable the second insulating member to exert a better insulating effect, further reduce the risk of short circuit in the battery cell, and help improve the reliability of the battery cell.

[0025] 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 electrode tab and a first current collecting member, the first electrode tab is connected to one end of the main body facing the first wall portion along the first direction, the first electrode tab 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 electrode tab closest to the first wall portion.

[0026] In the above technical solution, the first pole lug is connected to the first electrode terminal through the first current collecting member, but the first pole lug is connected to the surface of the first current collecting member facing the first wall portion. The first pole lug is more likely to contact the first wall portion than the first current collecting member to cause a short circuit. At this time, the second insulating member is connected to the surface of the first pole lug closest to the first wall portion to insulate the first pole lug 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.

[0027] 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.

[0028] 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 conducive to improving the reliability of the battery cell.

[0029] 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.

[0030] 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 tab is reduced, thereby facilitating the connection between the first electrode terminal and the first tab.

[0031] 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 to the first electrode tab.

[0032] In the above technical solution, a clearance hole is provided in the second insulating member to clear the first electrode terminal, facilitating connection between the first tab and the first electrode terminal, thereby reducing material consumption for the second insulating member. Furthermore, since the first electrode terminal is inserted into the clearance hole, the clearance hole and the first electrode terminal cooperate to limit the second insulating member, preventing the second insulating member from deviating or shifting, thereby enabling the second insulating member to better perform its insulating function.

[0033] 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.

[0034] 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.

[0035] 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.

[0036] In the above technical solution, by wrapping the second insulating member around the first electrode lead-out portion, on the one hand, the first electrode lead-out portion can be effectively covered, thereby insulating and isolating the first electrode lead-out portion from the first wall portion. On the other hand, when the second insulating member is wrapped around the first electrode lead-out portion, the second insulating member is less likely to deviate or shift relative to the first electrode lead-out portion, thereby enabling the second insulating member to better perform its insulating function.

[0037] 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.

[0038] 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.

[0039] 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.

[0040] 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, the second insulating member is unlikely to melt, allowing the second insulating member to provide insulation and isolation, reducing the risk of battery cell short circuits.

[0041] 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.

[0042] 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, reducing the risk of short circuit of the battery cell, thereby improving the reliability of the battery cell.

[0043] As an optional technical solution of the embodiment of the present application, the positive electrode material of the battery cell includes lithium-containing phosphate.

[0044] In the above technical solution, the positive electrode material includes a battery cell containing lithium phosphate, which will generate a lot of heat when thermal runaway occurs, which can easily cause 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, the effect of arranging a second insulating member in the battery cell including the positive electrode material containing lithium phosphate is better.

[0045] 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 manganese iron phosphate, and a composite material of lithium manganese iron phosphate and carbon.

[0046] In a second aspect, an embodiment of the present application further provides a battery, which includes the above-mentioned battery cell.

[0047] In a third aspect, an embodiment of the present application further provides an electrical device, which includes the above-mentioned battery cell. BRIEF DESCRIPTION OF THE DRAWINGS

[0048] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the following is a brief introduction to the drawings required for use in the embodiments. 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 relevant drawings can be obtained based on these drawings without creative work.

[0049] FIG1 is a schematic structural diagram of a vehicle provided in some embodiments of the present application;

[0050] FIG2 is an exploded view of a battery provided in some embodiments of the present application;

[0051] FIG3 is a schematic structural diagram of a battery cell provided in some embodiments of the present application;

[0052] FIG4 is an exploded view of a battery cell provided in some embodiments of the present application;

[0053] FIG5 is a schematic structural diagram of a second insulating member connected to a first current collecting member according to some embodiments of the present application;

[0054] FIG6 is an exploded view of a second insulating member and a first current collecting member provided in some embodiments of the present application;

[0055] FIG7 is a schematic structural diagram of a second insulating member connected to a first current collecting member according to other embodiments of the present application;

[0056] FIG8 is an exploded view of a second insulating member and a first current collecting member provided in some other embodiments of the present application;

[0057] FIG9 is a schematic structural diagram of a second insulating member connected to a first current collecting member according to some other embodiments of the present application;

[0058] FIG10 is an exploded view of a second insulating member and a first current collecting member provided in still other embodiments of the present application;

[0059] FIG11 is an exploded view of a battery cell provided in some embodiments of the present application.

[0060] Icons: 10 - housing; 11 - first part; 12 - second part; 20 - battery cell; 21 - housing; 211 - end cap; 212 - housing; 213 - first wall; 22 - electrode assembly; 221 - main body; 222 - first electrode lead; 2221 - first tab; 2222 - first current collecting member; 22221 - main body; 22222 - protrusion; 2222a - first surface; 2222b - second surface; 2222c - third surface ;22223-first connecting part; 22224-second connecting part; 22225-covering area; 22226-non-covering area; 223-second electrode lead-out part; 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

[0061] To make the purpose, technical solutions, and advantages of the embodiments of this application more clear, the technical solutions in the embodiments of this application will be clearly described below in conjunction with the drawings in the embodiments of this application. Obviously, the described embodiments are part of the embodiments of this application, not all of the embodiments. Based on the embodiments in this application, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of this application.

[0062] Unless otherwise defined, all technical and scientific terms used in this application have the same meanings as commonly understood by those skilled in the art to which this application belongs. The terms used in the specification of this application are for the purpose of describing specific embodiments only and are not intended to limit this application. The terms "including" and "having" and any variations thereof in the specification and claims of this application and the above-mentioned drawings are intended to cover non-exclusive inclusions. The terms "first" and "second" 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-secondary relationship.

[0063] References to "embodiments" in this application mean that a particular feature, structure, or characteristic described in connection with the embodiment may be included in at least one embodiment of the application. The appearance of this phrase in various places in the specification does not necessarily refer to the same embodiment, nor does it constitute an independent or alternative embodiment that is mutually exclusive of other embodiments.

[0064] In the description of this application, it should be noted that, unless otherwise expressly specified or limited, the terms "mounted," "connected," "connected," and "attached" should be understood in a broad sense. For example, they may refer to fixed connections, detachable connections, or integral connections; they may refer to direct connections, indirect connections through an intermediate medium, or internal connections between two components. Those skilled in the art will understand the specific meanings of the above terms in this application based on specific circumstances.

[0065] The term "and / or" in this application simply describes an association between related objects, indicating that three possible relationships exist. For example, A and / or B can represent: A exists alone, A and B exist simultaneously, and B exists alone. In addition, the character " / " in this application generally indicates that the related objects are in an "or" relationship.

[0066] In the embodiments of this application, the same reference numerals represent the same components, and for the sake of brevity, detailed descriptions of the same components in different embodiments are omitted. It should be understood that the thickness, length, width, and other dimensions of the various components in the embodiments of this application, as well as the overall thickness, length, width, and other dimensions of the integrated device shown in the drawings are merely illustrative and should not constitute any limitation on this application.

[0067] The term "plurality" used in this application refers to two or more (including two).

[0068] 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.

[0069] The battery cells can be lithium-ion batteries, sodium-ion batteries, sodium-lithium-ion batteries, lithium metal batteries, sodium metal batteries, lithium-sulfur batteries, magnesium-ion batteries, nickel-hydrogen batteries, nickel-cadmium batteries, lead-acid batteries, etc., which are not limited in the embodiments of the present application.

[0070] A battery cell typically includes an electrode assembly. This assembly includes a positive electrode, a negative electrode, and a separator. During the charge and discharge process of a battery cell, active ions (such as lithium ions) are inserted and removed between the positive and negative electrodes. The separator, placed between the positive and negative electrodes, prevents short circuits between the positive and negative electrodes while allowing the active ions to pass through.

[0071] In some embodiments, the positive electrode may be a positive electrode sheet, which 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.

[0072] 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 provided on either or both of the two facing surfaces of the positive electrode current collector.

[0073] 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 layer 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.).

[0074] 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 battery positive electrode active materials may also be used. These positive electrode active materials may 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 at least one of its modified compounds, etc.

[0075] In some embodiments, a positive electrode may utilize a metal foam. The metal foam may include nickel foam, copper foam, aluminum foam, alloy foam, or the like. When a metal foam is used as the positive electrode, the surface of the metal foam may or may not include a positive electrode active material. For example, a lithium source material, potassium metal, or sodium metal may be filled or / and deposited within the metal foam, where the lithium source material is lithium metal and / or a lithium-rich material.

[0076] In some embodiments, the negative electrode may be a negative electrode sheet, and the negative electrode sheet may include a negative electrode current collector.

[0077] As an example, the negative electrode current collector may be a metal foil, a metal foam, 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 metal foam may be nickel foam, copper foam, aluminum foam, alloy foam, etc. The composite current collector may include a polymer material base layer 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.).

[0078] 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.

[0079] 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 provided on either or both of the two facing surfaces of the negative electrode current collector.

[0080] As an example, the negative electrode active material may adopt the negative electrode active material for battery cells that is well 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.

[0081] 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.

[0082] In some embodiments, the electrode assembly further includes a separator disposed between the positive electrode and the negative electrode.

[0083] In some embodiments, the separator is a separator membrane. There are many types of separator membranes, and any known separator membrane with a porous structure having good chemical stability and mechanical stability can be selected.

[0084] As an example, the separator can be made of at least one of fiberglass, non-woven fabric, polyethylene, polypropylene, and polyvinylidene fluoride. The separator can be a single-layer film or a multi-layer composite film. In the case of a multi-layer composite film, the materials of each layer can be the same or different. The separator can be a separate component positioned between the positive and negative electrodes, or it can be attached to the surfaces of the positive and negative electrodes.

[0085] In some embodiments, the separator is a solid electrolyte, which is disposed between the positive electrode and the negative electrode and serves to transport ions and isolate the positive and negative electrodes.

[0086] In some embodiments, the battery cell further includes an electrolyte, which acts as a conductor of ions between the positive and negative electrodes. The electrolyte can be liquid, gel, or solid. Liquid electrolytes include an electrolyte salt and a solvent.

[0087] 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 bisoxalatoborate, lithium difluorodioxalatophosphate, and lithium tetrafluorooxalatophosphate.

[0088] In some embodiments, the solvent may include at least one of ethylene carbonate, propylene carbonate, ethyl methyl carbonate, diethyl carbonate, dimethyl carbonate, dipropyl carbonate, methylpropyl carbonate, ethylpropyl 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.

[0089] Among them, the gel electrolyte includes a skeleton network with a polymer as the electrolyte, combined with an ionic liquid-lithium salt.

[0090] Among them, solid electrolytes include polymer solid electrolytes, inorganic solid electrolytes, and composite solid electrolytes.

[0091] 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, or the like.

[0092] 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.

[0093] As an example, a composite solid electrolyte is formed by adding an inorganic solid electrolyte filler to a polymer solid electrolyte.

[0094] 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.

[0095] In some embodiments, the electrode assembly is a laminate structure.

[0096] As an example, multiple positive electrode sheets and multiple negative electrode sheets can be provided respectively, and the multiple positive electrode sheets and the multiple negative electrode sheets can be alternately stacked.

[0097] 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.

[0098] As an example, both the positive electrode sheet and the negative electrode sheet are folded to form a plurality of stacked folded segments.

[0099] As an example, a plurality of separators may be provided, each of which is disposed between any adjacent positive electrode sheets or negative electrode sheets.

[0100] As an example, the separator may be provided continuously, and may be provided between any adjacent positive electrode sheets or negative electrode sheets by folding or winding.

[0101] In some embodiments, the shape of the electrode assembly can be cylindrical, flat, or polygonal.

[0102] In some embodiments, the electrode assembly is provided with tabs that can conduct current from the electrode assembly. The tabs include a positive tab and a negative tab.

[0103] In some embodiments, a 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 (e.g., polypropylene), a composite metal housing (e.g., a copper-aluminum composite housing), or an aluminum-plastic film.

[0104] As an example, the battery cells may be cylindrical, prismatic, soft-pack or other shaped battery cells. Prismatic battery cells include but are not limited to square-shell, blade-shaped, and polygonal batteries, such as hexagonal batteries.

[0105] 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.

[0106] 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.

[0107] 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 housed in the case.

[0108] 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.

[0109] In some embodiments, the battery may be an energy storage device, including an energy storage container, an energy storage cabinet, and the like.

[0110] Currently, market developments indicate that batteries are increasingly being used. They are not only used in energy storage systems such as hydropower, thermal, wind, and solar power plants, but are also widely used in electric vehicles like electric bicycles, electric motorcycles, and electric cars, as well as in military equipment and aerospace. As battery applications continue to expand, market demand is also growing.

[0111] The development of battery technology requires simultaneous consideration of multiple design factors, including performance parameters such as battery life, energy density, discharge capacity, and charge / discharge rate. Furthermore, battery reliability must be considered. However, current battery reliability is relatively poor.

[0112] Batteries typically include multiple cells to provide higher voltage and capacity. If a cell experiences thermal runaway, the heat generated can easily transfer to adjacent cells, causing the temperature of these cells to reach 200°C. However, the lower plastic of the cell (the insulating member used to isolate the end caps and electrode assemblies) melts at 160-180°C, making it easy for the end caps and electrode assemblies to come into direct contact, resulting in a short circuit. This further increases the temperature of the cell, ultimately leading to heat diffusion and poor battery reliability.

[0113] In view of this, an embodiment of the present application provides a battery cell, which includes a shell, an electrode assembly, a first insulating member, and a second insulating member. The shell has a first wall portion, and the electrode assembly is accommodated in the shell. The electrode assembly includes a first electrode lead-out portion and a main body portion, and the first electrode lead-out portion is arranged at one end of the main body portion facing the first wall portion along the 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.

[0114] The battery cell is provided with a first insulating member and a second insulating member. During normal use, the first insulating member and the second insulating member can both insulate and isolate the first electrode lead-out portion from the first wall portion, reducing the risk of a short circuit caused by contact between the first electrode lead-out portion and the first wall portion. Because 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, to a certain extent, play the role of insulating and isolating the first electrode lead-out portion from the first wall portion, reducing the risk of a short circuit caused by contact between the first electrode lead-out portion and the first wall portion. In this way, even if another battery cell adjacent to the battery cell experiences thermal runaway, it is not easy to cause a short circuit in the battery cell and continue to cause thermal runaway, which is beneficial to limiting heat diffusion and improving the reliability of the battery cell.

[0115] The technical solutions described in the embodiments of the present application are applicable to batteries and electrical devices using batteries.

[0116] Electrically powered devices may include vehicles, mobile phones, portable devices, laptop computers, ships, spacecraft, electric toys, and electric tools. Spacecraft include airplanes, rockets, space shuttles, and spacecraft. Electric toys include fixed or mobile electric toys, such as game consoles, electric car toys, electric ship toys, and electric airplane toys. Electric tools include metal cutting power tools, grinding power tools, assembly power tools, and railway power tools, such as electric drills, electric grinders, electric wrenches, electric screwdrivers, electric hammers, impact drills, concrete vibrators, and electric planers. The embodiments of the present application do not impose any special restrictions on the above-mentioned electrical devices.

[0117] For the convenience of description, the following embodiments are described by taking the electric device as a vehicle 1000 as an example.

[0118] Please refer to Figure 1, which is a schematic structural diagram of a vehicle 1000 provided in some embodiments of the present application. The vehicle 1000 can be a fuel vehicle, a gas vehicle or a new energy vehicle. The new energy vehicle can 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 can be provided at the bottom, head or tail of the vehicle 1000. The battery 100 can be used to power the vehicle 1000. For example, the battery 100 can serve as an operating power source for the vehicle 1000. The vehicle 1000 may also include a controller 200 and a motor 300. 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.

[0119] In some embodiments of the present application, the battery 100 can serve not only as an operating power source for the vehicle 1000, but also 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.

[0120] Please refer to Figure 2, which is an exploded view of a battery 100 provided in some embodiments of the present application. The battery 100 includes a housing 10 and a battery cell 20, with the battery cell 20 housed within the housing 10. The housing 10 provides a storage space for the battery cell 20 and can have various structures. In some embodiments, the housing 10 can include a first portion 11 and a second portion 12, which overlap each other and together define a storage space for the battery cell 20. The second portion 12 can be a hollow structure with one end open. The first portion 11 can be a plate-like structure, with the first portion 11 overlapping the open side of the second portion 12, so that the first portion 11 and the second portion 12 together define a storage space. Alternatively, the first portion 11 and the second portion 12 can each be a hollow structure with one end open, with the open side of the first portion 11 overlapping the open side of the second portion 12. Of course, the housing 10 formed by the first portion 11 and the second portion 12 can have various shapes, such as a cylinder, a rectangular parallelepiped, etc.

[0121] 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 hybrid connection. A hybrid connection refers to a combination of series and parallel connections among the multiple battery cells 20. The multiple battery cells 20 may be directly connected in series, in parallel, or in a hybrid connection, and then the entire battery cell 20 may be housed within the housing 10. Alternatively, the battery 100 may be constructed by first connecting multiple battery cells 20 in series, in parallel, or in a hybrid connection to form a battery module, which is then connected in series, in parallel, or in a hybrid connection to form a complete battery module, and then housed within the housing 10. The battery 100 may also include other structures, such as a busbar assembly for electrically connecting the multiple battery cells 20.

[0122] Each battery cell 20 may be a secondary battery cell or a primary battery cell; it may also be 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.

[0123] Please refer to Figures 3 and 4. Figure 3 is a schematic structural diagram of a battery cell 20 provided in some embodiments of the present application. Figure 4 is an exploded view of a battery cell 20 provided in some embodiments of the present application. An embodiment of the present application provides a battery cell 20, the battery cell 20 including a shell 21, an electrode assembly 22, a first insulating member 23 and a second insulating member 24. The shell 21 has a first wall portion 213, and the electrode assembly 22 is accommodated in the shell 21. The electrode assembly 22 includes a first electrode lead-out portion 222 and a main body portion 221. 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.

[0124] The battery cell 20 refers to the smallest unit constituting the battery 100 .

[0125] The housing 21 includes an end cap 211 and a shell 212. The shell 212 has an accommodation space with one end open for accommodating the electrode assembly 22. The end cap 211 is connected to the shell 212 and closes the opening.

[0126] 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.

[0127] The housing 212 is a component that cooperates with the end cap 211 to form the internal environment of the battery cell 20. This internal environment can be used to accommodate the electrode assembly 22, electrolyte, and other components. The housing 212 and the end cap 211 can be separate components. An opening can be provided in the housing 212, and the end cap 211 is placed over the opening to form the internal environment of the battery cell 20. Alternatively, the end cap 211 and the housing 212 can be integrated. Specifically, the end cap 211 and the housing 212 can form a common joint surface before other components are inserted into the housing. When the interior of the housing 212 is to be enclosed, the end cap 211 is placed over the housing 212. The housing 212 can have a variety of shapes and sizes, such as a rectangular parallelepiped, a cylindrical shape, or a hexagonal prism. Specifically, the shape of the housing 212 can be determined based on the specific shape and size of the electrode assembly 22. The housing 212 can be made of a variety of materials, such as copper, iron, aluminum, stainless steel, aluminum alloy, plastic, etc., and this embodiment of the present application does not impose any particular limitations on this.

[0128] The electrode assembly 22 is a component in the battery cell 20 where electrochemical reactions occur. One or more electrode assemblies 22 may be contained 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 portions of the positive and negative electrode sheets containing active materials constitute the main body 221 of the electrode assembly 22, and the portions of the positive and negative electrode sheets without active materials each constitute a tab. The positive tab and the negative tab 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.

[0129] The first wall portion 213 may be the end cap 211 of the housing 21, or a wall of the shell 212 of the housing 21. In some implementations, as shown in Figures 3 and 4, the first wall portion 213 is the end cap 211. In other embodiments, the first wall portion 213 may be the bottom wall of the shell 212 opposite the end cap 211. In still other embodiments, the first wall portion 213 may be a side wall of the shell 212 adjacent to and connected to the end cap 211.

[0130] The first electrode lead-out portion 222 is a structure used to extract electrical energy from the main body 221 or introduce electrical energy into the main body 221. The first electrode lead-out portion 222 includes at least the positive or negative tab described above and may also include other electrical connection components connected to the positive or negative tab. The first electrode lead-out portion 222 is disposed at one end of the main body 221 facing the first wall 213 along the first direction. In other words, the first electrode lead-out portion 222 is located between the first wall 213 and the main body 221 along the first direction.

[0131] 3 and 4 , the first direction may be the X direction shown in the figures.

[0132] The first insulating member 23 is commonly known as the lower plastic. The first insulating member 23 is disposed inside the first wall portion 213 and is used to isolate the first electrode lead portion 222 from the first wall portion 213 to reduce the risk of short circuit. For example, the insulating member can be plastic, rubber, etc.

[0133] The second insulating member 24 is partially or entirely disposed between the first electrode lead portion 222 and the first wall portion 213 along the first direction to insulate and isolate the first electrode lead portion 222 from the first wall portion 213. During normal use of the battery cell 20, both the first insulating member 23 and the second insulating member 24 can insulate and isolate the first electrode lead portion 222 from the first wall portion 213.

[0134] The material damage temperature of a substance can be either its melting point or its decomposition temperature. If a substance decomposes at a certain temperature, that temperature is considered the decomposition temperature. If a substance has both a melting point and a decomposition temperature, the decomposition temperature is considered the material damage temperature. If a substance only has a melting point but no decomposition temperature, the melting point is considered the material damage temperature. If a substance only has a decomposition temperature but no melting point, the decomposition temperature is considered the material damage temperature.

[0135] 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, reducing the risk of short circuit caused by contact between the first electrode lead-out portion 222 and the first wall portion 213.

[0136] The battery cell 20 is provided with a first insulating member 23 and a second insulating member 24. During normal use, both the first insulating member 23 and the second insulating member 24 insulate and isolate the first electrode lead portion 222 from the first wall portion 213, reducing the risk of a short circuit caused by contact between the first electrode lead portion 222 and the first wall portion 213. Because the material damage temperature of the second insulating member 24 is higher than the material damage temperature of the first insulating member 23, if another battery cell 20 adjacent to the battery cell 20 experiences thermal runaway, causing the first insulating member 23 of that battery cell 20 to melt, the second insulating member 24 can still effectively insulate and isolate the first electrode lead portion 222 from the first wall portion 213, reducing the risk of a short circuit caused by contact between the first electrode lead portion 222 and the first wall portion 213. This reduces the risk of a short circuit caused by contact between the first electrode lead portion 222 and the first wall portion 213. This reduces the risk of a short circuit caused by contact between the first electrode lead portion 222 and the first wall portion 213, even if another battery cell 20 adjacent to the battery cell 20 experiences thermal runaway. This helps limit heat spread and improves the reliability of the battery cell 20.

[0137] Please refer to Figures 3, 4, 5, and 6. Figure 5 is a schematic diagram of the structure of the second insulating member 24 connected to the first current collecting member 2222 according to some embodiments of the present application. Figure 6 is an exploded view of the second insulating member 24 and the first current collecting member 2222 according to some embodiments of the present application. In some embodiments, the second insulating member 24 is connected to the first electrode lead-out portion 222.

[0138] The second insulating member 24 is directly connected to the first electrode lead portion 222. The first insulating member 23 can be fixedly connected to the first electrode lead portion 222, for example, the first connector is bonded to the first electrode lead portion 222. The first insulating member 23 can also be detachably connected to the first electrode lead portion 222, for example, the first insulating member 23 is snap-fitted to the first electrode lead portion 222.

[0139] By connecting the second insulating member 24 to the first electrode lead-out portion 222, on the one hand, since the first insulating member 23 is disposed on the surface of the first wall portion 213 facing the electrode assembly 22, connecting the second insulating member 24 to the first electrode lead-out portion 222 is more convenient and less likely 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, allowing the second insulating member 24 to be stably located between the first electrode lead-out portion 222 and the first wall portion 213, thereby insulating and isolating the first electrode lead-out portion 222 from the first wall portion 213.

[0140] Referring to Figures 3, 4, 5, and 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 portion 222 includes a first electrode tab 2221 and a first current collecting member 2222. 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. A second insulating member 24 is connected to the first current collecting member 2222 and is at least partially located between the first current collecting member 2222 and the first wall portion 213 along the first direction.

[0141] The first electrode terminal 25 is used to be electrically connected to the first electrode lead-out portion 222 to input or output electrical energy of the battery cell 20 .

[0142] 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 .

[0143] Optionally, the first current collecting member 2222 may be a sheet-like structure, for example, a transition sheet.

[0144] 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 .

[0145] The first electrode tab 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 electrode tab 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 conducive to improving the reliability of the battery cell 20.

[0146] 5 and 6 , 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 a 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.

[0147] The body portion 22221 is the portion of the first current collecting member 2222 primarily used for connection to the first tab 2221. The protrusion 22222 is the portion of the first current collecting member 2222 primarily used for connection to the first electrode terminal 25. The protrusion 22222 is connected to the body portion 22221 and protrudes from the body portion 22221 along a first direction.

[0148] Because the protrusion 22222 is connected to the first electrode terminal 25, even if the first insulating member 23 is melted, the protrusion 22222 is unlikely to come into contact with the first wall portion 213, thereby causing a short circuit between the first electrode lead portion 222 and the first wall portion 213. Compared to the protrusion 22222, the body 22221 is more likely to come into contact with the first wall portion 213 when the first insulating member 23 is melted, thereby causing a short circuit between the first electrode lead portion 222 and the first wall portion 213.

[0149] The first surface 2222a is the surface of the main body 22221 closest to the first wall 213 along the first direction and is also the surface of the main body 22221 most likely to contact the first wall 213 and cause a short circuit. The second insulating member 24 can cover a portion of the first surface 2222a, or it can completely cover the first surface 2222a, thereby reducing the risk of a short circuit caused by contact between the first surface 2222a and the first wall 213.

[0150] The first surface 2222a is the surface of the main body 22221 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.

[0151] Please refer to Figures 5, 6, 7, and 8. Figure 7 is a schematic diagram of the structure of the second insulating member 24 connected to the first current collecting member 2222 according to other embodiments of the present application. Figure 8 is an exploded view of the second insulating member 24 and the first current collecting member 2222 according to other embodiments of the present application. In other embodiments, along the first direction, the main body 22221 includes a first connecting portion 22223 and a second connecting portion 22224, the second connecting portion 22224 being connected to the first connecting portion 22223, and the first tab 2221 being connected to the first connecting portion 22223. Along the first direction, the surface of the first connecting portion 22223 facing the first wall portion 213 is a first surface 2222a, and the second connecting portion 22224 has a second surface 2222b facing the first wall portion 213, with the first surface 2222a being closer to the first wall portion 213 than the second surface 2222b. The protrusion 22222 protrudes from the second surface 2222 b , and the second insulating member 24 covers at least a portion of the second surface 2222 b .

[0152] The first connecting portion 22223 is the portion of the main body 22221 primarily used for connecting to the first tab 2221. The first connecting portion 22223 is connected to the second connecting portion 22224. The protrusion 22222 is provided on the second connecting portion 22224 to facilitate connection to the first electrode terminal 25, thereby reducing the difficulty of connecting the first electrode terminal 25 and the first tab 2221.

[0153] 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 main body portion 22221 closest to the first wall portion 213.

[0154] 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.

[0155] 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 contact between the second surface 2222b and the first wall 213.

[0156] The main body 22221 includes a first surface 2222a and a second surface 2222b. The first surface 2222a is the surface closest to the first wall 213, and the second surface 2222b is farther from the first wall 213 than the first surface 2222a. Because both the first surface 2222a and the second surface 2222b pose a risk of short circuiting due to contact with the first wall 213, the second insulating member 24 covers at least a portion of the first surface 2222a and at least a portion of the second surface 2222b to better insulate the first current collecting member 2222 from the first wall 213. This improves the insulation performance of the second insulating member 24, further reducing the risk of short circuiting in the battery cells 20 and improving the reliability of the battery cells 20.

[0157] Optionally, in some embodiments, the main body 22221 further 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.

[0158] Referring to Figures 4, 5, 6, 7, and 8, in some embodiments, a battery cell 20 includes a plurality of electrode assemblies 22 arranged along a second direction intersecting the first direction. The second surface 2222b includes a covered region 22225 covered by the second insulating member 24 and an uncovered region 22226 uncovered by the second insulating member 24. Along the second direction, both sides of the uncovered region 22226 are connected to the covered region 22225. A protrusion 22222 is provided in the uncovered region 22226.

[0159] The second direction is the arrangement direction of the plurality of electrode assemblies 22. Referring to FIG. 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. In the embodiment shown in FIG. 4 , the second direction is perpendicular to the first direction.

[0160] The covered area 22225 refers to the area of ​​the second surface 2222b covered by the second insulating member 24. The uncovered area 22226 refers to the area of ​​the second surface 2222b not covered by the second insulating member 24. Covered areas 22225 are provided on both sides of the uncovered 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, but does not cover the middle area of ​​the second surface 2222b along the second direction.

[0161] Both sides of the non-covered area 22226 are connected to the covered area 22225. In comparison, the covered area 22225 is closer to the other battery cell 20 adjacent to the current cell 20. When the other battery cell 20 experiences thermal runaway, the areas of the first insulating member 23 near the ends along the second direction will be hotter and more easily melted, while the area near the center of the first insulating member 23 will be cooler and less likely to melt. The covered areas 22225 correspond to the areas of the first insulating member 23 that are easily melted, while the non-covered areas 22226 correspond to the areas of the first insulating member 23 that are relatively less likely to melt. The first insulating member 23 and the second insulating member 24 work together to effectively insulate and isolate the first current collecting member 2222 from the first wall portion 213, reducing the risk of short circuits in the battery cells 20 and improving the reliability of the battery cells 20.

[0162] Referring to Figures 4, 5, 6, 7, and 8, in some embodiments, a battery cell 20 includes a plurality of electrode assemblies 22 arranged along a second direction that intersects the first direction. The body 22221 includes a plurality of first connecting portions 22223 arranged at intervals along the second direction, and a second connecting portion 22224 connecting the plurality of first connecting portions 22223. Each first connecting portion 22223 is connected to a first tab 2221 of an electrode assembly 22.

[0163] The main body 22221 may include two first connecting portions 22223, three first connecting portions 22223, four first connecting portions 22223, or more than four first connecting portions 22223. The plurality of first connecting portions 22223 are spaced apart along the second direction. Referring to Figures 5, 6, 7, and 8, in the embodiments shown in Figures 5, 6, 7, and 8, the main body 22221 includes two first connecting portions 22223, spaced apart along the second direction. A second connecting portion 22224 connects the two first connecting portions 22223.

[0164] Each first connecting portion 22223 is connected to the first electrode tab 2221 of an electrode assembly 22 , that is, the first connecting portion 22223 corresponds to the first electrode tab 2221 in a one-to-one manner.

[0165] Each first connecting portion 22223 is connected to the first pole tab 2221 of an electrode assembly 22, and the second connecting portion 22224 is connected to multiple first connecting portions 22223 to achieve electrical connection between the first current collecting member 2222 and the first pole tabs 2221 of multiple electrode assemblies 22. Connecting the first pole tabs 2221 of multiple electrode assemblies 22 and the first electrode terminal 25 through the first current collecting member 2222 is beneficial to reducing the difficulty of assembling between the first pole tab 2221 and the first electrode terminal 25.

[0166] Please refer to Figures 9 and 10. Figure 9 is a schematic diagram of the structure of the second insulating member 24 connected to the first current collecting member 2222 according to further embodiments of the present application. Figure 10 is an exploded view of the second insulating member 24 and the first current collecting member 2222 according to further 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 main body 22221 facing the first wall portion 213 that is not occupied by the protrusion 22222.

[0167] Along the first direction, the surface of the main body 22221 facing the first wall 213 includes a first region and a second region. The first region is occupied by the protrusion 22222, that is, the protrusion 22222 is located in the first region. The second region is the region of the surface of the main body 22221 facing the first wall 213 not occupied by the protrusion 22222. The second insulating member 24 completely covers the second region.

[0168] 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.

[0169] 9 and 10 , in some embodiments, the second insulating member 24 is provided with an escape hole 241 , and the protrusion 22222 passes through the escape hole 241 and is connected to the first electrode terminal 25 .

[0170] The avoidance hole 241 is a through hole extending along the first direction through the second insulating member 24. 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.

[0171] The protruding portion 22222 is passed through the avoidance 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 .

[0172] Providing a clearance hole 241 on the second insulating member 24 to allow for the protrusion 22222 to be connected to the first electrode terminal 25 facilitates the reduction of material consumption for the second insulating member 24. Furthermore, because the protrusion 22222 is disposed within the clearance hole 241, the clearance hole 241 and the protrusion 22222 cooperate to limit the second insulating member 24, preventing the second insulating member 24 from deviating or shifting, thereby enabling the second insulating member 24 to better perform its insulating function.

[0173] 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 .

[0174] When the first electrode tab 2221 is connected to the side of the first current collecting member 2222 facing 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 facing away from the first wall 213 .

[0175] 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 than the first pole ear 2221 to cause a short circuit. 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 improve the reliability of the battery cell 20.

[0176] 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 portion 222 includes a first electrode tab 2221 and a first current collecting member 2222. The first electrode tab 2221 is connected to one end of the main body 221 facing the first wall portion 213 in the first direction. The first electrode tab 2221 is connected to a surface of the first current collecting member 2222 facing the first wall portion 213. 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 electrode tab 2221 closest to the first wall portion 213.

[0177] The first tab 2221 may be bent around the first current collecting member 2222 so as to be connected to the surface of the first current collecting member 2222 facing the first wall 213. At this time, a portion of the first tab is located between the first current collecting member 2222 and the first wall 213 along the first direction.

[0178] 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.

[0179] 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 than the first current collecting member 2222 to cause a short circuit. 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 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 improve the reliability of the battery cell 20.

[0180] Please refer to Figure 11, which is an exploded view of a battery cell 20 provided in some embodiments of the present application. 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 portion 222 includes a first electrode tab 2221, which is connected to the first electrode terminal 25. The second insulating member 24 is connected to the first electrode tab 2221. Along the first direction, the second insulating member 24 is at least partially located between the first electrode tab 2221 and the first wall portion 213.

[0181] 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 conduct 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 .

[0182] The second insulating member 24 is connected to the first electrode tab 2221 . The second insulating member 24 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 .

[0183] The first pole lug 2221 is directly connected to the first electrode terminal 25, and the second insulating member 24 is connected to the first pole lug 2221, and the second insulating member 24 is at least partially located between the first pole lug 2221 and the first wall portion 213 to insulate the first pole lug 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.

[0184] 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 .

[0185] “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 .

[0186] 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 tab 2221 is reduced, thereby facilitating the connection between the first electrode terminal 25 and the first tab 2221 .

[0187] Referring to FIG. 11 , in some embodiments, the second insulating member 24 is provided with an escape hole 241 , and the first electrode terminal 25 passes through the escape hole 241 and is connected to the first electrode tab 2221 .

[0188] The avoidance hole 241 is a through hole extending along the first direction through the second insulating member 24. 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.

[0189] The first electrode terminal 25 is passed through the avoidance hole 241 , and one end of the first electrode terminal 25 is connected to the first electrode tab 2221 .

[0190] Providing a clearance hole 241 on the second insulating member 24 to avoid the first electrode terminal 25 facilitates connection between the first tab 2221 and the first electrode terminal 25, thereby reducing material consumption for the second insulating member 24. Furthermore, since the first electrode terminal 25 is disposed within the clearance hole 241, the clearance hole 241 and the first electrode terminal 25 cooperate to limit the second insulating member 24, preventing the second insulating member 24 from deviating or shifting, thereby enabling the second insulating member 24 to better perform its insulating function.

[0191] In other embodiments, the second insulating member 24 may also be disposed on the first wall portion 213. For example, the first insulating member 23 may be provided with a receiving hole, and the second insulating member 24 may be connected to the first wall portion 213 and received within the receiving hole. If thermal runaway occurs in another battery cell 20 adjacent to the battery cell 20, causing the first insulating member 23 of the battery cell 20 to melt, the second insulating member 24 may still be able to insulate and isolate the first electrode lead portion 222 from the first wall portion 213 to a certain extent, reducing the risk of a short circuit caused by contact between the first electrode lead portion 222 and the first wall portion 213.

[0192] 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 apart 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.

[0193] In some embodiments, the second insulating member 24 is bonded to the first electrode lead portion 222 .

[0194] 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.

[0195] By bonding the second insulating member 24 to the first electrode lead portion 222 , the second insulating member 24 is connected to the first electrode lead 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 its insulating effect.

[0196] In some other embodiments, the second insulating member 24 covers the first electrode lead portion 222 .

[0197] 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 may cover only the first electrode lead portion 222, or may cover both the first electrode tab 2221 and the first electrode lead portion 222. In the embodiment where the first electrode lead portion 222 includes only the first electrode tab 2221, the second insulating member 24 covers the first electrode tab 2221.

[0198] By wrapping the second insulating member 24 around the first electrode lead-out portion 222, on the one hand, the first electrode lead-out portion 222 can be effectively 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 wrapped around the first electrode lead-out portion 222, the second insulating member 24 is unlikely to deviate or shift relative to the first electrode lead-out portion 222, thereby enabling the second insulating member 24 to better perform its insulating function.

[0199] In some embodiments, the second insulating member 24 is an insulating film connected to the first electrode lead portion 222 .

[0200] Optionally, the second insulating member 24 is a PI film (Polyimide Film) connected to the first electrode lead-out portion 222 .

[0201] The second insulating member 24 is an insulating film, which can effectively insulate and isolate the first electrode lead 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.

[0202] In some embodiments, the material damage temperature of the second insulating member 24 is greater than or equal to 300° C.

[0203] When another battery cell 20 adjacent to the battery cell 20 experiences thermal runaway, the temperature inside the battery cell 20 can 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, the second insulating member 24 is unlikely to melt. This allows the second insulating member 24 to provide insulation and isolation, reducing the risk of short circuits in the battery cells 20.

[0204] Optionally, the material of the second insulating member 24 includes at least one of polyimide, polyetheretherketone, and polytetrafluoroethylene.

[0205] 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.

[0206] In some embodiments, the electrode assembly 22 includes a second electrode lead portion 223, which 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 opposite ends of the main body 221.

[0207] When the first electrode lead portion 222 and the second electrode lead portion 223 are located at the same end of the main body 221, the first insulating member 23 can also insulate and isolate the second electrode lead portion 223 from the first wall portion 213. The battery cell 20 also 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 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 portion 223 from the first wall portion 213 when the first insulating member 23 melts.

[0208] 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 portion 223 may include a second electrode tab 2231, which has an opposite polarity to the first electrode tab 2221 and is connected to one end of the main body 221 facing the first wall portion 213 in the first direction. The second current collecting member 2232 connects the second electrode terminal 27 and the second electrode tab 2231. The third insulating member 26 may be connected to the second current collecting member 2232. The specific connection method of the third insulating member 26 to the second current collecting member 2232 can be similar to the connection method of the second insulating member 24 to the first current collecting member 2222 described above and will not be further described here. In other embodiments, the second electrode lead portion 223 includes a second electrode tab 2231, which has an opposite polarity to the first electrode tab 2221 and is connected to the second electrode terminal 27. The third insulating member 26 can be connected to the second tab 2231 . The specific method of connecting the third insulating member 26 to the second tab 2231 can refer to the aforementioned method of connecting the second insulating member 24 to the first tab 2221 , which will not be repeated here.

[0209] 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 outer shell 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 from 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. 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 from the second wall portion when the fourth insulating member melts.

[0210] The battery cell 20 includes a second electrode terminal 27, which is disposed on the second wall. In some embodiments, the second electrode lead portion 223 may include a second electrode tab 2231, which has an opposite polarity to the first electrode tab 2221 and is connected to one end of the main body 221 facing the second wall in the first direction. The second current collecting member 2232 connects the second electrode terminal 27 and the second electrode tab 2231. The third insulating member 26 may be connected to the second current collecting member 2232. The specific connection method of the third insulating member 26 to the second current collecting member 2232 can be similar to the connection method of the second insulating member 24 to the first current collecting member 2222 described above and will not be further described here. In other embodiments, the second electrode lead portion 223 includes a second electrode tab 2231, which has an opposite polarity to the first electrode tab 2221 and is connected to the second electrode terminal 27. The third insulating member 26 can be connected to the second tab 2231 . The specific method of connecting the third insulating member 26 to the second tab 2231 can refer to the aforementioned method of connecting the second insulating member 24 to the first tab 2221 , which will not be repeated here.

[0211] In some embodiments, the third insulating member 26 is bonded to the second electrode lead portion 223 .

[0212] In the embodiment where the second electrode lead 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 portion 223 includes only the second electrode tab 2231, the third insulating member 26 is bonded to the second electrode tab 2231.

[0213] By bonding the third insulating member 26 to the second electrode lead portion 223 , the third insulating member 26 is connected to the second electrode lead portion 223 in a simple and convenient manner, which helps to limit the position of the third insulating member 26 so that the third insulating member 26 can stably exert its insulating effect.

[0214] In some other embodiments, the third insulating member 26 covers the second electrode lead portion 223 .

[0215] 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 cover only the second electrode lead-out portion 223, or may cover both the second electrode tab 2231 and the second electrode lead-out portion 223. In the embodiment where the second electrode lead-out portion 223 includes only the second electrode tab 2231, the third insulating member 26 covers the second electrode tab 2231.

[0216] By wrapping the third insulating member 26 around the second electrode lead portion 223, on the one hand, the second electrode lead portion 223 can be effectively covered, thereby insulating the second electrode lead portion 223 from the first wall portion 213 or the second wall portion. On the other hand, when the third insulating member 26 is wrapped around the second electrode lead portion 223, the third insulating member 26 is unlikely to deviate or shift relative to the second electrode lead portion 223, thereby enabling the third insulating member 26 to better perform its insulating function.

[0217] In some embodiments, the third insulating member 26 is an insulating film connected to the second electrode lead-out portion 223 .

[0218] Optionally, the third insulating member 26 is a PI film (Polyimide Film) connected to the second electrode lead-out portion 223 .

[0219] The third insulating member 26 is an insulating film, which can effectively insulate and isolate 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 without occupying too much space inside the shell 21, so that the battery cell 20 can still have a high energy density.

[0220] In some embodiments, the material damage temperature of the third insulating member 26 is greater than or equal to 300°C.

[0221] When another battery cell 20 adjacent to the current battery cell 20 experiences thermal runaway, the temperature inside the current battery cell 20 can 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 current battery cell 20 experiences thermal runaway, the third insulating member 26 is unlikely to melt. This allows the third insulating member 26 to provide insulation and isolation, reducing the risk of short circuits in the battery cells 20.

[0222] Optionally, the material of the third insulating member 26 includes at least one of polyimide, polyetheretherketone, and polytetrafluoroethylene.

[0223] 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, reducing the risk of short circuit of the battery cell 20, thereby improving the reliability of the battery cell 20.

[0224] In some embodiments, the positive electrode material of the battery cell 20 includes a lithium-containing phosphate.

[0225] The positive electrode material includes a battery cell 20 containing lithium phosphate, which will generate a lot of heat when thermal runaway occurs, which can 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.

[0226] 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 manganese iron phosphate, and a composite material of lithium manganese iron phosphate and carbon.

[0227] The embodiment of the present application further provides a battery 100 , which includes the above-mentioned battery cell 20 .

[0228] An embodiment of the present application further provides an electrical device, which includes the above-mentioned battery cell 20.

[0229] According to some embodiments of the present application, please refer to Figures 3 to 10.

[0230] An embodiment of the present application provides a battery cell 20, comprising 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 213, and the electrode assembly 22 is housed within the housing 21. The electrode assembly 22 includes a first electrode lead portion 222 and a main body 221. The first electrode lead portion 222 is disposed at one end of the main body 221 facing the first wall 213 along a first direction. The first insulating member 23 is disposed on a surface of the first wall 213 facing the electrode assembly 22 along the first direction. The first insulating member 23 is used to insulate and separate the first electrode lead portion 222 from the first wall 213. At least a portion of the second insulating member 24 is disposed between the first electrode lead portion 222 and the first wall 213 along the first direction. 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 separate the first electrode lead portion 222 from the first wall 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. During normal use, both the first insulating member 23 and the second insulating member 24 insulate and isolate the first electrode lead portion 222 from the first wall portion 213, reducing the risk of a short circuit caused by contact between the first electrode lead portion 222 and the first wall portion 213. Because the material damage temperature of the second insulating member 24 is higher than the material damage temperature of the first insulating member 23, if another battery cell 20 adjacent to the battery cell 20 experiences thermal runaway, causing the first insulating member 23 of that battery cell 20 to melt, the second insulating member 24 can still effectively insulate and isolate the first electrode lead portion 222 from the first wall portion 213, reducing the risk of a short circuit caused by contact between the first electrode lead portion 222 and the first wall portion 213. This reduces the risk of a short circuit caused by contact between the first electrode lead portion 222 and the first wall portion 213. This reduces the risk of a short circuit caused by contact between the first electrode lead portion 222 and the first wall portion 213, even if another battery cell 20 adjacent to the battery cell 20 experiences thermal runaway. This helps limit heat spread and improves the reliability of the battery cell 20.

[0231] The battery cell 20 includes a first electrode terminal 25, which is disposed on the first wall portion 213. The first electrode lead portion 222 includes a first electrode tab 2221 and a first current collecting member 2222. The first electrode tab 2221 is connected to one end of the main body 221 facing the first wall portion 213 in the first direction. 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 is at least partially located between the first current collecting member 2222 and the first wall portion 213 in the first direction. The first electrode tab 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 electrode tab 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 conducive to improving the reliability of the battery cell 20.

[0232] 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 a first direction. The body portion 22221 is connected to the first 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 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.

[0233] Along the first direction, the main body 22221 includes a first connecting portion 22223 and a second connecting portion 22224. The second connecting portion 22224 is connected to the first connecting portion 22223, and the first tab 2221 is connected to the first connecting portion 22223. Along the first direction, the surface of the first connecting portion 22223 facing the first wall portion 213 is a first surface 2222a. The second connecting 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. 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 main body 22221 includes a first surface 2222a and a second surface 2222b. The first surface 2222a is the surface closest to the first wall 213, and the second surface 2222b is farther from the first wall 213 than the first surface 2222a. Because both the first surface 2222a and the second surface 2222b pose a risk of short circuiting due to contact with the first wall 213, the second insulating member 24 covers at least a portion of the first surface 2222a and at least a portion of the second surface 2222b to better insulate the first current collecting member 2222 from the first wall 213. This improves the insulation performance of the second insulating member 24, further reducing the risk of short circuiting in the battery cells 20 and improving the reliability of the battery cells 20.

[0234] The battery cell 20 includes a plurality of electrode assemblies 22 arranged along a second direction intersecting the first direction. The second surface 2222b includes a covered area 22225 covered by the second insulating member 24 and an uncovered area 22226 not covered by the second insulating member 24. Along the second direction, both sides of the uncovered area 22226 are connected to the covered areas 22225, and the protrusion 22222 is provided in the uncovered area 22226. Both sides of the uncovered area 22226 are connected to the covered areas 22225, and the covered area 22225 is closer to the adjacent battery cell 20. When another battery cell 20 experiences thermal runaway, the areas near the ends of the first insulating member 23 along the second direction are hotter and more easily melted, while the areas near the center of the first insulating member 23 are cooler and less likely to melt. The covered areas 22225 correspond to the areas of the first insulating member 23 that are easily melted, while the uncovered areas 22226 correspond to the areas of the first insulating member 23 that are less likely to melt. The first insulating member 23 and the second insulating member 24 work together to effectively insulate and isolate the first current collecting member 2222 from the first wall portion 213, reducing the risk of short circuits in the battery cell 20 and improving its reliability.

[0235] 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 portion 222 includes a first electrode tab 2221, which is connected to the first electrode terminal 25. A second insulating member 24 is connected to the first electrode tab 2221, and along the first direction, the second insulating member 24 is at least partially located between the first electrode tab 2221 and the first wall portion 213. The first electrode tab 2221 is directly connected to the first electrode terminal 25, and the second insulating member 24 is connected to the first electrode tab 2221 and is at least partially located between the first electrode tab 2221 and the first wall portion 213 to insulate the first electrode tab 2221 from the first wall portion 213. This provides a better insulation effect for the second insulating member 24, further reducing the risk of short circuiting in the battery cell 20 and improving the reliability of the battery cell 20.

[0236] The first insulating member 23 can also insulate and separate the second electrode lead portion 223 from the first wall portion 213. The battery cell 20 also 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 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 separate the second electrode lead portion 223 from the first wall portion 213 when the first insulating member 23 melts.

[0237] 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 portion 223 may include a second electrode tab 2231 and a second current collecting member 2232. The second electrode tab 2231 has an opposite polarity to the first electrode tab 2221 and is connected to one end of the main body 221 facing the first wall portion 213 in the first direction. The second current collecting member 2232 connects the second electrode terminal 27 and the second electrode tab 2231. The third insulating member 26 may be connected to the second current collecting member 2232. The specific method of connecting the third insulating member 26 to the second current collecting member 2232 can be similar to the method of connecting the second insulating member 24 to the first current collecting member 2222, and will not be repeated here.

[0238] The second insulating member 24 is an insulating film bonded to the first current collecting member 2222. Bonding the second insulating member 24 to the first current collecting member 2222 facilitates simple and convenient connection of the second insulating member 24 to the first current collecting member 2222. This helps restrict the position of the second insulating member 24, ensuring that it can consistently provide its insulating effect. The second insulating member 24 is an insulating film that effectively isolates the first current collecting member 2222 from the first wall 213 while maintaining sufficient space within the housing 21, allowing the battery cells 20 to maintain a high energy density.

[0239] The above description is merely a preferred embodiment of the present application and is not intended to limit the present application. Various modifications and variations are possible for those skilled in the art. Any modifications, equivalent substitutions, or improvements made within the spirit and principles of the present application shall be included within the scope of protection of the present application.

Claims

1. A battery cell, wherein, Comprising: A housing having a first wall portion; An electrode assembly received within the housing, the electrode assembly including a first electrode lead-out portion and a main body portion, the first electrode lead-out portion being disposed 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 disposed 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-out portion and the first wall portion; A second insulating member, along the first direction, at least a part 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, wherein The second insulating member is connected to the first electrode lead-out portion.

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

4. The battery cell according to claim 3, wherein, The first current collector 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 tab, and the protruding portion is connected to the first electrode terminal; Along the first direction, the body portion has a first surface closest to the first wall portion, and the second insulating member covers at least a part of the first surface.

5. The battery cell according to claim 4, wherein Along the first direction, the 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 tab is connected to the first connecting portion, along the first direction, a 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 protruding portion protrudes from the second surface, and the second insulating member covers at least a part of the second surface.

6. The battery cell according to claim 5, wherein, The battery cell includes a plurality of electrode assemblies arranged along a second direction, and the second direction intersects the first direction; The second surface includes a covered area covered by the second insulating member and a non-covered area not covered by the second insulating member, and along the second direction, both sides of the non-covered area are connected to the covered area, and the protruding portion is disposed in the non-covered area.

7. The battery cell according to claim 5 or 6, wherein The battery cell includes a plurality of electrode assemblies arranged along a second direction, and the second direction intersects the first direction; The body portion includes a plurality of the first connecting portions, the plurality of the first connecting portions are arranged at intervals along the second direction, the second connecting portion connects the plurality of the first connecting portions, and each of the first connecting portions connects the first tab of one of the electrode assemblies.

8. The battery cell according to any one of claims 4-7, wherein Along the first direction, the second insulating member completely covers the 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 any one of claims 4-8, wherein The second insulating member is provided with an avoidance hole, and the protruding portion passes through the avoidance hole and is connected to the first electrode terminal.

10. The battery cell according to any one of claims 3-9, wherein, The first 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, wherein, 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 tab and a first current collecting member. The first tab is connected to one end of the body portion facing the first wall portion along the first direction. The first tab 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; The second insulating member is connected to the surface of the first tab closest to the first wall portion.

12. The battery cell according to claim 2, wherein, 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 tab, and the first tab is connected to the first electrode terminal; The second insulating member is connected to the first tab. Along the first direction, the second insulating member is at least partially located between the first tab and the first wall portion.

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

14. The battery cell according to claim 12 or 13, wherein, The second insulating member is provided with an avoidance hole, and the first electrode terminal passes through the avoidance hole and is connected to the first tab.

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

16. The battery cell according to any one of claims 2-15, wherein, The second insulating member covers the first electrode lead-out portion.

17. The battery cell according to any one of claims 2-16, wherein, The second insulating member is an insulating film connected to the first electrode lead-out portion.

18. The battery cell according to any one of claims 1-17, wherein, 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, wherein, The material of the second insulating member includes at least one of polyimide, polyether ether ketone, and polytetrafluoroethylene.

20. The battery cell according to any one of claims 1-19, wherein, The positive electrode material of the battery cell includes a lithium-containing phosphate.

21. The battery cell according to claim 20, wherein, 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 manganese iron phosphate, and a composite material of lithium manganese iron phosphate and carbon.

22. A battery, wherein, Including the battery cell according to any one of claims 1-21.

23. An electrical device, wherein, Including the battery cell according to any one of claims 1-21.

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