Battery monomer, battery device and electric device

Abstract

The utility model provides a battery cell, a battery device and a power utilization device. The battery cell includes a housing having a first wall portion, an electrode assembly housed within the housing, a first insulator, and a second insulator. The electrode assembly comprises a tab and a main body part, and the tab is arranged at one end of the main body part. The first insulating part is at least partially arranged between the electrode assembly and the first wall part, and the first insulating part is used for insulating and isolating the electrode assembly and the first wall part. The second insulating part is at least partially arranged between the main body part and the first insulating part and is connected to the first insulating part, and the material damage temperature of the second insulating part is higher than that of the first insulating part. And when the other battery monomer adjacent to the battery monomer is subjected to thermal runaway, the second insulating part can prevent high-temperature melt generated after the first insulating part is melted from dripping to the main body part to a certain extent, so that the risk that the main body part is scalded to further cause thermal runaway is reduced, and the reliability of the battery monomer is improved.

Description

Technical Field

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

[0002] Batteries are widely used in the new energy field, such as in electric vehicles and new energy vehicles, which have become a new trend in the automotive industry. The development of battery technology must consider multiple design factors simultaneously, such as battery life, energy density, discharge capacity, and charge / discharge rate. Furthermore, battery reliability must also be considered. However, current batteries have relatively poor reliability. Utility Model Content

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

[0004] In a first aspect, embodiments of this application provide a battery cell, the battery cell including a casing, an electrode assembly, a first insulating member, and a second insulating member, the casing having a first wall portion; the electrode assembly being housed within the casing, the electrode assembly including a tab and a main body portion, the tab being disposed at one end of the main body portion; the first insulating member being at least partially disposed between the electrode assembly and the first wall portion, the first insulating member being used to insulate and isolate the electrode assembly and the first wall portion; the second insulating member being at least partially disposed between the main body portion and the first insulating member, and connected to the first insulating member, the material damage temperature of the second insulating member being greater than the material damage temperature of the first insulating member.

[0005] In the above technical solution, the battery cell is equipped with a first insulating component and a second insulating component. During normal use, both the first and second insulating components can insulate and isolate the main body and the first wall, reducing the risk of a short circuit due to contact between the main body and the first wall. Since the material damage temperature of the second insulating component is higher than that of the first insulating component, when another battery cell adjacent to this battery cell experiences thermal runaway, causing the first insulating component of this battery cell to melt, the second insulating component can still, to a certain extent, insulate and isolate the main body and the first wall, reducing the risk of a short circuit due to contact between the main body and the first wall. Thus, even if another battery cell adjacent to this battery cell experiences thermal runaway, it is less likely to cause a short circuit in this battery cell and further trigger thermal runaway, which helps limit heat diffusion and improves the reliability of the battery cell. Furthermore, when another battery cell adjacent to this battery cell experiences thermal runaway, causing the first insulating component of this battery cell to melt, the second insulating component can, to a certain extent, prevent the high-temperature molten material generated after the first insulating component melts from dripping onto the main body, reducing the risk of the main body being burned and further triggering thermal runaway, which helps improve the reliability of the battery cell.

[0006] As an optional technical solution in this application embodiment, the first insulating member includes a body portion and a protrusion portion. The body portion is at least partially disposed between the electrode assembly and the first wall portion. The protrusion portion protrudes from the body portion in a direction facing the electrode assembly. Along the thickness direction of the first wall portion, the protrusion portion is disposed opposite to the body portion. The second insulating member is at least partially disposed between the body portion and the protrusion portion and is connected to the protrusion portion.

[0007] In the above technical solution, the main body is at least partially disposed between the electrode assembly and the first wall. During normal use, both the main body and the second insulating member can insulate and isolate the main body and the first wall, reducing the risk of short circuit due to contact between the main body and the first wall. The protrusion protrudes from the main body in the direction facing the electrode assembly, and the protrusion is disposed opposite to the main body in the thickness direction of the first wall, so that the protrusion can restrict the range of movement of the main body within the casing. Since the protrusion is closer to the main body than the main body, when another battery cell adjacent to the battery cell experiences thermal runaway, causing the first insulating member of that battery cell to melt, the protrusion is more likely to damage the main body. By disposing at least partially between the main body and the protrusion and connecting it to the protrusion, the second insulating member can better prevent the high-temperature molten material generated after the first insulating member melts from dripping onto the main body, reducing the risk of the main body being burned and further triggering thermal runaway, which is beneficial to improving the reliability of the battery cell.

[0008] As an optional technical solution in this application embodiment, the protrusion is pressed against the main body by the second insulating member.

[0009] In the above technical solution, the protrusion is pressed against the main body by the second insulating member. On the one hand, this restricts the movement of the main body in the thickness direction of the first wall, which helps improve the reliability of the connection between the main body and other electrical connection components and reduces the risk of damage to the main body. On the other hand, the main body can support the second insulating member to a certain extent, which helps to keep the second insulating member between the main body and the first insulating member. In this way, when another battery cell adjacent to the battery cell experiences thermal runaway, causing the first insulating member of that battery cell to melt, the second insulating member can better prevent the high-temperature molten material generated after the first insulating member melts from dripping onto the main body, reducing the risk of the main body being burned and further triggering thermal runaway, which helps to improve the reliability of the battery cell.

[0010] As an optional technical solution in this application embodiment, the second insulating member includes a first insulating part and a second insulating part, the first insulating part being connected to the surface of the protrusion facing the main body part, and the second insulating part being connected to the surface of the body part facing the main body part.

[0011] In the above technical solution, when another battery cell adjacent to the battery cell experiences thermal runaway, causing the first insulating part of the battery cell to melt, the first insulating part can prevent the high-temperature melt generated after the protrusion melts from dripping onto the main body, and the second insulating part can prevent the high-temperature melt generated after the main body melts from dripping onto the main body, thereby reducing the risk of the main body being burned and further causing thermal runaway, which is beneficial to improving the reliability of the battery cell.

[0012] As an optional technical solution in this application embodiment, the first insulating part and the second insulating part are separately disposed and not connected to each other.

[0013] In the above technical solution, by separately providing the first insulating part and the second insulating part and not connecting them to each other, the first insulating part can be connected to the protrusion and the second insulating part can be connected to the main body, making assembly simpler and more convenient.

[0014] As an optional technical solution in this application embodiment, the second insulating member includes a third insulating portion, which connects the first insulating portion and the second insulating portion.

[0015] In the above technical solution, by setting a third insulating part to connect the first insulating part and the second insulating part, on the one hand, the integrity of the second insulating component can be improved. On the other hand, along the thickness direction of the first wall, the second insulating component can cover more area of ​​the first insulating component. When another battery cell adjacent to this battery cell experiences thermal runaway, causing the first insulating component of that battery cell to melt, the second insulating component can better insulate and isolate the main body and the first wall, and can also better prevent the high-temperature molten material generated after the first insulating component melts from dripping onto the main body, which is beneficial to improving the reliability of the battery cell.

[0016] As an optional technical solution in this application embodiment, the first insulating part, the second insulating part and the third insulating part are integrally formed.

[0017] In the above technical solution, by integrally molding the first insulating part, the second insulating part, and the third insulating part, the second insulating member has better overall integrity. Furthermore, even if one of the first insulating part, the second insulating part, or the third insulating part separates from the first insulating member, the separated portion can be held between the first insulating member and the main body by the action of the other parts, thereby insulatingly isolating the main body and the first wall portion when the first insulating member melts.

[0018] As an optional technical solution in this application embodiment, the battery cell includes an electrode terminal disposed on the outer casing; the battery cell includes a current collector connecting the electrode terminal and the tab; along the thickness direction of the first wall portion, the second insulating member is partially disposed opposite to the body portion, and the current collector is at least partially disposed between the body portion and the second insulating member.

[0019] In the above technical solution, the current collector connects the electrode terminals and the tabs, enabling the electrode terminals to output electrical energy to the electrode assembly or input electrical energy to the electrode assembly. Along the thickness direction of the first wall portion, a portion of the second insulating member is disposed between the body portion and the main body portion, and another portion is disposed between the protrusion and the main body portion. When another battery cell adjacent to this battery cell experiences thermal runaway, causing the first insulating member of that battery cell to melt, the second insulating member can both insulate and isolate the main body portion and the first wall portion, and prevent the high-temperature molten material generated after the first insulating member melts from dripping onto the main body portion, thus improving the reliability of the battery cell. Furthermore, since the current collector is at least partially disposed between the body portion and the second insulating member, the second insulating member can also reduce the risk of a short circuit caused by the current collector inserting into the main body portion when the main body portion shifts.

[0020] As an optional technical solution in this application embodiment, the second insulating member includes a first insulating portion and a second insulating portion; along the thickness direction of the first wall portion, the first insulating portion is at least partially disposed between the main body portion and the first insulating member, and connected to the first insulating member; along a first direction, the main body portion has two opposing first surfaces, the second insulating portion is connected to one of the first surfaces, and the first direction is perpendicular to the thickness direction of the first wall portion.

[0021] In the above technical solution, the first insulating portion is at least partially disposed between the main body and the first insulating member along the thickness direction of the first wall portion. During normal use, both the first insulating member and the first insulating portion can insulate and isolate the main body and the first wall portion, reducing the risk of a short circuit due to contact between the main body and the first wall portion. Since the material damage temperature of the second insulating member is greater than that of the first insulating member, when another battery cell adjacent to this battery cell experiences thermal runaway, causing the first insulating member of that battery cell to melt, the first insulating portion can still, to a certain extent, insulate and isolate the main body and the first wall portion, reducing the risk of a short circuit due to contact between the main body and the first wall portion. Furthermore, when another battery cell adjacent to this battery cell experiences thermal runaway, causing the first insulating member of that battery cell to melt, the first insulating portion can, to a certain extent, prevent the high-temperature molten material generated after the first insulating member melts from dripping onto the main body, reducing the risk of the main body being burned and further triggering thermal runaway, thus improving the reliability of the battery cell. The second insulating portion is connected to the first surface. On the one hand, it restricts the relative positions of the first insulating portion and the main body, and the second insulating portion and the main body to a certain extent, allowing the first insulating portion to be more stably positioned between the main body and the first insulating member. This insulates and isolates the main body and the first wall portion, and prevents the high-temperature molten material generated after the first insulating member melts from dripping onto the main body, which is beneficial to improving the reliability of the battery cell. On the other hand, the second insulating portion can reduce the risk of short circuits caused by the first surface contacting other components, which is beneficial to improving the reliability of the battery cell.

[0022] As an optional technical solution in this application embodiment, the outer shell includes a second wall portion, which is connected to the first wall portion, and the second wall portion is the wall portion with the largest outer surface area in the outer shell; along the first direction, the second insulating portion is at least partially located between the main body portion and the second wall portion.

[0023] In the above technical solution, the second insulating portion is at least partially located between the main body portion and the second wall portion along the first direction to insulate and isolate the main body portion and the second wall portion. Because the material damage temperature of the second insulating component is high, when another battery cell adjacent to this battery cell experiences thermal runaway, the second insulating portion can still, to a certain extent, insulate and isolate the main body portion and the second wall portion, reducing the risk of a short circuit due to contact between the main body portion and the second wall portion. Thus, even if another battery cell adjacent to this battery cell experiences thermal runaway, it is less likely to cause a short circuit in this battery cell and further trigger thermal runaway, which helps limit heat diffusion and improve the reliability of the battery cell. Furthermore, since the second wall portion has the largest outer surface area in the casing, when another battery cell adjacent to this battery cell experiences thermal runaway, heat can easily be transferred from the second wall portion to the main body portion, causing the insulating component of the main body portion to shrink due to heat. The second insulating portion can, to a certain extent, prevent heat transfer to the main body portion, thereby reducing the risk of the insulating component shrinking due to high temperature, making the positive and negative electrode plates less likely to be exposed, which helps improve the reliability of the battery cell.

[0024] As an optional technical solution in this application embodiment, each electrode assembly is provided with at least one second insulating member. The second insulating member includes two second insulating portions. The first insulating portion connects to the two second insulating portions, and the two second insulating portions are respectively connected to the two first surfaces of the main body.

[0025] In the above technical solution, each electrode assembly is provided with at least one second insulating member, and the two second insulating parts of each second insulating member are respectively connected to the two first surfaces of the main body, so that each electrode assembly can be well protected. Furthermore, during manufacturing, each second insulating member can be individually connected to each electrode assembly and the first insulating member, which helps to reduce production difficulty.

[0026] As an optional technical solution in this application embodiment, the battery cell includes a plurality of electrode assemblies stacked along the first direction, and along the first direction, in two adjacent second insulating members, a second insulating portion of one second insulating member is connected to a second insulating portion of the other second insulating member.

[0027] In the above technical solution, by connecting one second insulating part of one second insulating member to one second insulating part of another second insulating member, two adjacent second insulating members can be connected together. In this way, even if the connection between one of the multiple second insulating members and the electrode assembly and / or the first insulating member fails, the relative position of the second insulating member and the electrode assembly can be maintained to a certain extent. This allows the second insulating member to insulate and isolate its corresponding electrode assembly and the first wall portion, and prevents the high-temperature melt generated after the first insulating member melts from dripping onto the main body portion, which is beneficial to improving the reliability of the battery cell.

[0028] As an optional technical solution in this application embodiment, the battery cell includes a plurality of electrode components stacked along the first direction, wherein two electrode components located at both ends of the first direction are a first electrode component and a second electrode component, respectively; the second insulating member includes two second insulating portions, one second insulating portion is connected to a first surface of the first electrode component away from the second electrode component, and the other second insulating portion is connected to a first surface of the second electrode component away from the first electrode component.

[0029] In the above technical solution, along the thickness direction of the first wall portion, a second insulating member is located between the main body of the multiple electrode assemblies and the first insulating member. This second insulating member not only provides insulation between the main body of the multiple electrode assemblies and the first wall portion, exhibiting good insulation performance, but also prevents the high-temperature molten material generated after the first insulating member melts from dripping onto the main body, thus improving the reliability of the battery cell. Furthermore, the location of the second insulating member between the main body of the multiple electrode assemblies and the first insulating member also helps reduce the space occupied inside the casing, thereby increasing the energy density of the battery cell.

[0030] As an optional technical solution in this application embodiment, the electrode assembly includes a positive electrode sheet, an insulating member, and a negative electrode sheet, wherein the positive electrode sheet, the insulating member, and the negative electrode sheet are wound or stacked; the first surface is the surface of the insulating member.

[0031] In the above technical solution, by connecting the second insulating part to the surface of the separator, on the one hand, it helps to fix the separator, maintain its shape, and reduce the risk of the separator shrinking due to high temperature, making the positive and negative electrode plates less likely to be exposed, thus improving the reliability of the battery cell. On the other hand, the second insulating part can, to a certain extent, prevent heat from being transferred to the separator, thereby reducing the risk of the separator shrinking due to high temperature, making the positive and negative electrode plates less likely to be exposed, thus improving the reliability of the battery cell.

[0032] As an optional technical solution in this application embodiment, the second insulating member is a flat plate structure.

[0033] In the above technical solution, when the second insulating member is a flat plate structure, on the one hand, it is easier to manufacture the second insulating member and reduces its cost. On the other hand, the second insulating member does not need to extend between the main body and other walls, and it is less likely to form a stepped structure on the outside of the main body, thus reducing stress concentration in the electrode assembly.

[0034] As an optional technical solution in this application embodiment, each electrode assembly is provided with at least one second insulating element.

[0035] In the above technical solution, each electrode assembly is provided with at least one second insulating element, so that each electrode assembly can be well protected.

[0036] As an optional technical solution in this application embodiment, each of the second insulating members is located between the main body of the plurality of electrode assemblies and the first insulating member.

[0037] In the above technical solution, a second insulating component can not only achieve insulation isolation between the main body and the first wall of multiple electrode assemblies, providing good insulation, but also prevent the high-temperature molten material generated after the first insulating component melts from dripping onto the main body, thus improving the reliability of the battery cell. Furthermore, the second insulating component, located between the main body and the first insulating component of the multiple electrode assemblies, also helps reduce the space occupied inside the casing, thereby increasing the energy density of the battery cell.

[0038] As an optional technical solution in this application embodiment, along the thickness direction of the first wall portion, the main body portion has a first end facing the first wall portion; the electrode assembly includes two tabs, the two tabs have opposite polarities, and both tabs are disposed at the first end; the first insulating member is at least partially disposed between the first end and the first wall portion, and the second insulating member is at least partially disposed between the first end and the first wall portion.

[0039] In the above technical solution, the first insulating component, the second insulating component, and the two tabs are disposed at the same end of the main body. During normal use, both the first and second insulating components can insulate and isolate the main body and the first wall, reducing the risk of short circuit due to contact between the main body and the first wall. Since the material damage temperature of the second insulating component is higher than that of the first insulating component, when another battery cell adjacent to this battery cell experiences thermal runaway, causing the first insulating component of that battery cell to melt, the second insulating component can better insulate and isolate the main body and the first wall, and can also better prevent the high-temperature molten material generated after the first insulating component melts from dripping onto the main body, which is beneficial to improving the reliability of the battery cell.

[0040] As an optional technical solution in this application embodiment, the two electrodes are spaced apart at the first end along the second direction; along the second direction, the second insulating member is provided on the side of one electrode away from the other electrode.

[0041] In the above technical solution, along the second direction, a second insulating element can be provided on the side of one electrode ear that is away from the other electrode ear. In this way, the second insulating element is less likely to interfere with the electrode ear and can better insulate and isolate the main body and the first wall.

[0042] As an optional technical solution in this application embodiment, the housing includes a shell and an end cap, the shell has an opening, the end cap closes the opening, and the end cap is the first wall portion; the first insulating member is a lower plastic disposed on the side of the end cap facing the electrode assembly.

[0043] In the above technical solution, the end cap is the first wall portion, and the first insulating component is the lower plastic. During normal use, both the lower plastic and the second insulating component can insulate and isolate the main body portion and the first wall portion, reducing the risk of short circuits caused by contact between the main body portion and the first wall portion. Since the material damage temperature of the second insulating component is higher than that of the lower plastic, when another battery cell adjacent to this battery cell experiences thermal runaway, causing the lower plastic of that battery cell to melt, the second insulating component can better insulate and isolate the main body portion and the first wall portion, and can also better prevent the high-temperature molten material generated after the lower plastic melts from dripping onto the main body portion, which is beneficial to improving the reliability of the battery cell.

[0044] As an optional technical solution in this application embodiment, the second insulating element is an insulating film.

[0045] In the above technical solution, the second insulating component is an insulating film. The insulating film can effectively insulate and isolate the main body and the first wall without taking up too much space inside the shell, so that the battery cell can still have a high energy density.

[0046] As an optional technical solution in this application embodiment, the thickness of the insulating film is H, which satisfies: 0.01mm≤H≤0.5mm.

[0047] In the above technical solution, when H ≥ 0.01 mm, the insulating film has a relatively large thickness, making it less prone to breakage and exhibiting good mechanical properties and insulation effect. This effectively prevents the high-temperature molten material generated after the first insulating component melts from dripping onto the main body. When H ≤ 0.5 mm, the insulating film thickness is not excessive, which helps reduce the space occupied by the battery cell and improves the energy density of the battery cell. Therefore, when 0.01 mm ≤ H ≤ 0.5 mm, both the insulation effect of the insulating film and the energy density of the battery cell can be balanced.

[0048] As an optional technical solution in this application embodiment, 0.05mm≤H≤0.2mm.

[0049] In the above technical solutions, when H ≥ 0.05 mm, the insulating film is thicker, less prone to breakage, and has better mechanical properties and insulation effect, effectively preventing the high-temperature molten material generated after the first insulating component melts and drips onto the main body. When H ≤ 0.2 mm, the insulating film thickness is not excessive, which helps reduce the space occupied by the battery cell and improves the energy density of the battery cell. Therefore, when 0.05 mm ≤ H ≤ 0.2 mm, a better balance can be struck between the insulation effect of the insulating film and the energy density of the battery cell.

[0050] As an optional technical solution in this application embodiment, the material damage temperature of the second insulating element is greater than or equal to 150°C.

[0051] In the above technical solution, by making the material damage temperature of the second insulating component greater than or equal to 150°C, when another battery cell adjacent to the battery cell experiences thermal runaway, the second insulating component is less likely to melt, thus enabling the second insulating component to play an insulating and isolating role and reducing the risk of short circuit in the battery cell.

[0052] As an optional technical solution in this application embodiment, the material damage temperature of the second insulating component is greater than or equal to 250°C.

[0053] In the above technical solution, by making the material damage temperature of the second insulating component greater than or equal to 250°C, when another battery cell adjacent to the battery cell experiences thermal runaway, the second insulating component is less likely to melt, thus enabling the second insulating component to play an insulating and isolating role and reducing the risk of short circuit in the battery cell.

[0054] As an optional technical solution in this application embodiment, the material of the second insulating member includes at least one of polyethylene terephthalate, polyphthalamide, polyphenylene sulfide, and polyimide.

[0055] In the above technical solutions, polyethylene terephthalate, polyphthalamide, polyphenylene sulfide, and polyimide have good high-temperature resistance and good insulation effect. They can insulate and isolate the body part and the first wall part when another battery cell adjacent to the battery cell experiences thermal runaway, thereby reducing the risk of short circuit in the battery cell and improving the reliability of the battery cell.

[0056] Secondly, embodiments of this application also provide a battery device, which includes the aforementioned battery cell.

[0057] Thirdly, embodiments of this application also provide an electrical device, which includes the aforementioned battery cell, and the battery cell is used to provide electrical energy to the electrical device. Attached Figure Description

[0058] To more clearly illustrate the technical solutions of the embodiments of this application, the accompanying drawings used in the embodiments will be briefly introduced below. It should be understood that the following drawings only show some embodiments of this application and should not be regarded as a limitation of the scope. For those skilled in the art, other related drawings can be obtained based on these drawings without creative effort.

[0059] Figure 1 This application provides structural schematic diagrams of vehicles for some embodiments;

[0060] Figure 2 Exploded views of battery devices provided in some embodiments of this application;

[0061] Figure 3 This is a schematic diagram of the structure of a battery cell provided in some embodiments of this application;

[0062] Figure 4 Exploded views of a single battery cell provided in some embodiments of this application;

[0063] Figure 5 This application provides schematic diagrams illustrating the connection between the first and second insulating members in some embodiments.

[0064] Figure 6 Exploded views of the first and second insulating elements provided in some embodiments of this application;

[0065] Figure 7 Schematic diagrams illustrating the connection between the first insulating member and the second insulating member as provided in other embodiments of this application;

[0066] Figure 8 Exploded views of the first and second insulating elements provided for other embodiments of this application;

[0067] Figure 9 A schematic diagram of the connection between the first insulating member and the second insulating member provided in some embodiments of this application;

[0068] Figure 10 Exploded views of the first and second insulating elements provided for some embodiments of this application;

[0069] Figure 11 A schematic diagram of the connection between the first insulating member and the second insulating member provided in some embodiments of this application;

[0070] Figure 12Exploded views of the first and second insulating elements provided in some embodiments of this application;

[0071] Figure 13 Exploded views of a battery cell provided in other embodiments of this application;

[0072] Figure 14 A top view schematic diagram of a battery cell provided for other embodiments of this application;

[0073] Figure 15 for Figure 14 A cross-sectional view at position AA in the middle;

[0074] Figure 16 Exploded views of a battery cell provided in some embodiments of this application;

[0075] Figure 17 A cross-sectional view of a battery cell provided for some embodiments of this application;

[0076] Figure 18 A cross-sectional view of a battery cell provided in some embodiments of this application;

[0077] Figure 19 Exploded views of a battery cell provided in some embodiments of this application;

[0078] Figure 20 This application also provides cross-sectional views of battery cells in some embodiments;

[0079] Figure 21 This is a schematic diagram of the structure of an electrode assembly provided in some embodiments of this application;

[0080] Figure 22 Exploded views of individual battery cells are also provided for some embodiments of this application.

[0081] Icons: 10-Box body; 11-First box body; 12-Second box body; 20-Battery cell; 21-Shell; 211-End cap; 212-Shell; 2121-Second wall; 213-First wall; 22-Electrode assembly; 221-Main body; 2211-First surface; 2212-Positive electrode; 2213-Separator; 2214-Negative electrode; 2215-First end; 222-Taper; 223-First electrode assembly; 224-Second electrode assembly; 23-First insulator; 231-Main body; 232-Protrusion; 24-Second insulator; 241-First insulator; 242-Second insulator; 243-Third insulator; 25-Electrode terminal; 26-Current collector; 100-Battery device; 200-Controller; 300-Motor; 1000-Vehicle. Detailed Implementation

[0082] To make the objectives, technical solutions, and advantages of the embodiments of this application clearer, the technical solutions of the embodiments of this application will be clearly described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0083] Unless otherwise defined, all technical and scientific terms used in this application have the same meaning as commonly understood by one of ordinary skill in the art to which this application pertains; the terminology used in the description of this application is for the purpose of describing particular embodiments only and is not intended to limit the application; the terms "comprising" and "having," and any variations thereof, in the description, claims, and accompanying drawings of this application are intended to cover non-exclusive inclusion. The terms "first," "second," etc., in the description, claims, or accompanying drawings of this application are used to distinguish different objects, not to describe a specific order or hierarchy.

[0084] In this application, the reference to "embodiment" means that a particular feature, structure, or characteristic described in connection with an embodiment may be included in at least one embodiment of this application. The appearance of this phrase in various places in the specification does not necessarily refer to the same embodiment, nor is it a separate or alternative embodiment that is mutually exclusive with other embodiments.

[0085] In the description of this application, it should be noted that, unless otherwise expressly specified and limited, the terms "installation," "connection," "linking," and "attachment" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal communication between two components. Those skilled in the art can understand the specific meaning of the above terms in this application according to the specific circumstances.

[0086] In this application, the term "and / or" is merely a description of the relationship between related objects, indicating that three relationships can exist. For example, A and / or B can represent: A existing alone, A and B existing simultaneously, or B existing alone. Additionally, in this application, the character " / " generally indicates that the preceding and following related objects have an "or" relationship.

[0087] In the embodiments of this application, the same reference numerals denote the same components, and for the sake of brevity, detailed descriptions of the same components are omitted in different embodiments. It should be understood that the thickness, length, width, and other dimensions of various components in the embodiments of this application shown in the accompanying drawings, as well as the overall thickness, length, width, and other dimensions of the integrated device, are merely illustrative and should not constitute any limitation on this application.

[0088] In this application, "multiple" means two or more (including two).

[0089] In this embodiment of the application, the battery cell can be a secondary battery, which refers to a battery cell that can be recharged to activate the active materials and continue to be used after the battery cell has been discharged.

[0090] Battery cells include, but are not limited to, lithium-ion batteries, sodium-ion batteries, sodium-lithium-ion batteries, lithium metal batteries, sodium metal batteries, lithium-sulfur batteries, magnesium-ion batteries, nickel-metal hydride batteries, nickel-cadmium batteries, lead-acid batteries, etc.

[0091] A single battery cell typically includes an electrode assembly. The electrode assembly includes a positive electrode, a negative electrode, and a separator. During the charging and discharging process of a single battery cell, active ions (such as lithium ions) repeatedly insert and extract between the positive and negative electrodes. The separator, positioned between the positive and negative electrodes, reduces the risk of short circuits while allowing active ions to pass through.

[0092] 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.

[0093] As an example, the positive current collector has two surfaces opposite each other in its own thickness direction, and the positive active material is disposed on either or both of the two opposite surfaces of the positive current collector.

[0094] As an example, the positive electrode current collector can be a metal foil or a composite current collector. For example, as a metal foil, it can be 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. Composite current collectors can include a polymer material base layer and a metal layer. Composite current collectors can 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.).

[0095] As an example, the positive electrode active material may include at least one of the following materials: lithium phosphate, lithium transition metal oxide, and their respective modified compounds. However, this application is not limited to these materials, and other conventional materials that can be used as positive electrode active materials in battery cells may also be used. These positive electrode active materials may be used alone or in combination of two or more. Examples of lithium phosphate may include, but are not limited to, at least one of lithium iron phosphate (such as LiFePO4 (also referred to as LFP)), lithium iron phosphate and carbon composites, lithium manganese phosphate (such as LiMnPO4), lithium manganese phosphate and carbon composites, lithium iron manganese phosphate, and lithium iron manganese phosphate and carbon composites. Examples of lithium transition metal oxide 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, and lithium nickel cobalt manganese oxide (such as LiNi). 1 / 3 Co 1 / 3Mn 1 / 3 O2 (also known as NCM) 333 LiNi 0.5 Co 0.2 Mn 0.3 O2 (also known as NCM) 523 LiNi 0.5 Co 0.25 Mn 0.25 O2 (also known as NCM) 211 LiNi 0.6 Co 0.2 Mn 0.2 O2 (also known as NCM) 622 LiNi 0.8 Co 0.1 Mn 0.1 O2 (also known as NCM) 811 ), lithium nickel cobalt aluminum oxide (such as LiNi) 0.85 Co 0.15 Al 0.05 At least one of O2 and its modified compounds.

[0096] In some embodiments, the positive electrode can be a foamed metal. The foamed metal can be foamed nickel, foamed copper, foamed aluminum, foamed alloys, etc. When foamed metal is used as the positive electrode, the surface of the foamed metal may or may not contain a positive electrode active material. As an example, lithium source material, potassium metal, or sodium metal can also be filled and / or deposited within the foamed metal, where the lithium source material is lithium metal and / or a lithium-rich material.

[0097] In some embodiments, the negative electrode may be a negative electrode sheet, and the negative electrode sheet may include a negative electrode current collector.

[0098] As an example, the negative electrode current collector can be a metal foil, a foamed metal, or a composite current collector. For example, as a metal foil, it can be aluminum with a silver-plated surface, stainless steel with a silver-plated surface, stainless steel, copper, aluminum, nickel, carbon electrodes, carbon, nickel, or titanium, etc. Foamed metal can be nickel foam, copper foam, aluminum foam, foam alloy, etc. Composite current collectors can include a polymer material base layer and a metal layer. Composite current collectors can 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.).

[0099] 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.

[0100] As an example, the negative electrode current collector has two surfaces opposite each other in its own thickness direction, and the negative electrode active material is disposed on either or both of the two opposite surfaces of the negative electrode current collector.

[0101] As an example, the negative electrode active material may be a negative electrode active material known in the art for use in battery cells. 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, and lithium titanate, etc. Silicon-based materials may be selected from at least one of elemental silicon, silicon oxide compounds, silicon-carbon composites, silicon-nitrogen composites, and silicon alloys. Tin-based materials may be selected from at least one of elemental tin, tin oxide compounds, and tin alloys. However, this application is not limited to these materials, and other conventional materials that can be used as negative electrode active materials in battery cells may also be used. These negative electrode active materials may be used alone or in combination of two or more.

[0102] In some embodiments, the positive current collector can be made of aluminum, and the negative current collector can be made of copper.

[0103] In some embodiments, the separator is a separator membrane. The separator membrane can be any known porous structure separator membrane with good chemical and mechanical stability.

[0104] As an example, the material of the separator may include at least one of glass fiber, nonwoven fabric, polyethylene, polypropylene, and polyvinylidene fluoride. The separator may be a single-layer film or a multi-layer composite film. When the separator is a multi-layer composite film, the materials of each layer may be the same or different. The separator may be a separate component located between the positive and negative electrodes, or it may be attached to the surfaces of the positive and negative electrodes.

[0105] In some embodiments, the battery cell also includes an electrolyte, which acts as a conductor of ions between the positive and negative electrodes. The electrolyte can be liquid, gel-like, or solid. Liquid electrolytes include electrolyte salts and solvents.

[0106] In some embodiments, the electrolyte salt may include at least one of lithium hexafluorophosphate, lithium tetrafluoroborate, lithium perchlorate, lithium hexafluoroarsenate, lithium bis(fluorosulfonyl)imide, lithium bis(trifluoromethanesulfonyl)imide, lithium trifluoromethanesulfonate, lithium difluorophosphate, lithium difluorooxalate borate, lithium dioxalate borate, lithium difluorodioxalate phosphate, and lithium tetrafluorooxalate phosphate.

[0107] In some embodiments, the solvent may include at least one selected from ethylene carbonate, propylene carbonate, methyl ethyl carbonate, diethyl carbonate, dimethyl carbonate, dipropyl carbonate, methyl propyl carbonate, ethyl propyl carbonate, butyl carbonate, fluoroethylene carbonate, methyl formate, methyl acetate, ethyl acetate, propyl acetate, methyl propionate, ethyl propionate, propyl propionate, methyl butyrate, ethyl butyrate, 1,4-butyrolactone, sulfolane, dimethyl sulfone, methyl ethyl sulfone, and diethyl sulfone. The solvent may also be an ether solvent. Ether solvents may include one or more selected from ethylene glycol dimethyl ether, ethylene glycol diethyl ether, diethylene glycol dimethyl ether, triethylene glycol dimethyl ether, tetraethylene glycol dimethyl ether, 1,3-dioxolane, tetrahydrofuran, methyl tetrahydrofuran, diphenyl ether, and crown ethers.

[0108] Among them, the gel electrolyte includes a polymer as the electrolyte backbone network, combined with an ionic liquid - lithium salt.

[0109] In some implementations, the electrode assembly is a wound structure. The positive and negative electrode sheets are wound into a wound structure.

[0110] In some implementations, the electrode assembly is a stacked structure.

[0111] As an example, multiple positive and negative electrodes can be set, and multiple positive and multiple negative electrodes can be stacked alternately.

[0112] As an example, multiple positive electrode plates can be provided, and negative electrode plates can be folded to form multiple stacked folded segments, with a positive electrode plate sandwiched between adjacent folded segments.

[0113] As an example, both the positive and negative electrode plates are folded to form multiple stacked folded segments.

[0114] As an example, multiple separators can be provided, each positioned between any adjacent positive or negative electrode plates.

[0115] As an example, the separators can be continuously arranged, either by folding or rolling between any adjacent positive or negative electrode plates.

[0116] In some implementations, the electrode assembly may be flat or polygonal in shape.

[0117] In some embodiments, the electrode assembly has tabs that allow current to be drawn from the electrode assembly. The tabs include a positive tab and a negative tab.

[0118] In some embodiments, the battery cell may include a housing. The housing is used to encapsulate components such as electrode assemblies and electrolytes. The housing may be made of steel, aluminum, or a composite metal (such as a copper-aluminum composite housing).

[0119] In some embodiments, the housing can be a sealed structure or a non-sealed structure. As an example, when the housing is a sealed structure, it can protect the electrode assembly and prevent, to some extent, electrolyte leakage. When the housing is a non-sealed structure, it can still protect the electrode assembly, and a sealing bag may be included between the housing and the electrode assembly to encapsulate the electrode assembly and electrolyte. Specifically, the sealing bag can be a bag-shaped insulating component or an aluminum-plastic film.

[0120] As an example, a battery cell can be a prismatic battery cell or a battery cell of other shapes. Prismatic battery cells include prismatic battery cells, blade-shaped battery cells, and multi-prismatic battery cells, such as hexagonal prismatic battery cells.

[0121] The battery apparatus mentioned in the embodiments of this application may include one or more battery cell assemblies for providing voltage and capacity. A battery cell assembly may include multiple battery cells, which are connected in series, parallel, or mixed connections via a busbar.

[0122] In some embodiments, a battery cell assembly is typically formed by arranging multiple battery cells; as an example, a battery cell assembly can be a battery module, which is formed by arranging multiple battery cells and fixing them together to form an independent module.

[0123] As an example, a battery module can be formed by bundling multiple battery cells together with cable ties.

[0124] In some embodiments, the battery device may be a battery pack, which may include a housing and one or more individual battery cells housed within the housing.

[0125] As an example, the battery cell assembly can be a battery module, and the battery cell assembly can be housed in the housing by fixing the battery module in the housing.

[0126] As an example, battery cell assemblies can also be housed in a housing by directly fixing multiple battery cells to the housing.

[0127] As an example, the enclosure may include a first enclosure body and a second enclosure body. The first enclosure body and the second enclosure body are fastened together to form a closed space inside the enclosure to house the individual battery cells. Here, "closed" refers to covering or closing, which can be either sealed or unsealed. The first enclosure body may be a top cover or a bottom plate.

[0128] As an example, the enclosure may include a top cover, a frame, and a bottom plate. The top cover and bottom plate are connected to the frame, creating an enclosed space inside the enclosure to house the individual battery cells.

[0129] As an example, the housing can be part of the vehicle's chassis structure. For instance, the housing's roof can be at least part of the vehicle's floor, or the housing's frame can be at least part of the vehicle's crossbeams and longitudinal beams.

[0130] In some embodiments, the battery device refers to an energy storage device, which includes a housing with a door on at least one side. Energy storage devices include energy storage containers, energy storage cabinets, etc.

[0131] Currently, judging from market trends, battery applications are becoming increasingly widespread. Batteries are not only used in energy storage systems such as hydropower, thermal power, wind power, and solar power plants, but also extensively in electric vehicles such as electric bicycles, electric motorcycles, and electric cars, as well as in military equipment and aerospace. With the continuous expansion of battery applications, market demand is also constantly increasing.

[0132] The development of battery technology must consider multiple design factors simultaneously, such as energy density, discharge capacity, and charge / discharge rate. Additionally, battery reliability must also be considered. However, current battery reliability is relatively poor.

[0133] Batteries typically consist of multiple cells to provide higher voltage and capacity. If one cell experiences thermal runaway, the heat generated can easily be conducted to adjacent cells, causing the lower plastic layer (the insulating material used to insulate the end caps and electrode assemblies) of those adjacent cells to melt. This can lead to direct contact between the end caps and electrode assemblies, causing a short circuit. This further increases the temperature of the cell, ultimately resulting in heat diffusion and poor battery reliability.

[0134] Therefore, this application provides a battery cell, which includes a casing, an electrode assembly, a first insulating member, and a second insulating member. The casing has a first wall, and the electrode assembly is housed within the casing. The electrode assembly includes a tab and a main body, with the tab disposed at one end of the main body. The first insulating member is at least partially disposed between the electrode assembly and the first wall, and serves to insulate and isolate the electrode assembly and the first wall. The second insulating member is at least partially disposed between the main body and the first insulating member, and is connected to the first insulating member. The material damage temperature of the second insulating member is greater than that of the first insulating member.

[0135] The battery cell is equipped with a first insulating component and a second insulating component. During normal use, both components effectively insulate the main body and the first wall, reducing the risk of a short circuit due to contact between the main body and the first wall. Because the material damage temperature of the second insulating component is higher than that of the first, even if a neighboring battery cell experiences thermal runaway, causing the first insulating component of the first battery cell to melt, the second insulating component can still provide insulation between the main body and the first wall to some extent, further reducing the risk of a short circuit. Thus, even if a neighboring battery cell experiences thermal runaway, it is less likely to cause a short circuit in the first battery cell, thus limiting heat diffusion and improving the reliability of the battery cell. Furthermore, when a neighboring battery cell experiences thermal runaway, causing the first insulating component of the first battery cell to melt, the second insulating component can, to some extent, prevent the high-temperature molten material from dripping onto the main body, reducing the risk of burns to the main body and further triggering thermal runaway, thus improving the reliability of the battery cell.

[0136] The technical solutions described in the embodiments of this application are applicable to various electrical devices that use battery cells and battery devices, such as mobile phones, portable devices, laptops, electric vehicles, electric toys, power tools, vehicles, ships and spacecraft, etc. For example, spacecraft include airplanes, rockets, space shuttles and spacecraft.

[0137] For ease of explanation, the following embodiments will use a vehicle as an example of an electrical device.

[0138] Please refer to Figure 1 , Figure 1 This is a schematic diagram of the structure of a vehicle 1000 provided in some embodiments of this application. A battery device 100 is disposed inside the vehicle 1000, and the battery device 100 may be located at the bottom, front, or rear of the vehicle 1000. The battery device 100 can be used to power the vehicle 1000; for example, the battery device 100 can serve as the operating power source for the vehicle 1000.

[0139] The vehicle 1000 may also include a controller 200 and a motor 300. The controller 200 is used to control the battery device 100 to supply power to the motor 300, for example, for the power needs of the vehicle 1000 during startup, navigation and driving.

[0140] In some embodiments of this application, the battery device 100 can not only serve as the operating power source for the vehicle 1000, but also as the driving power source for the vehicle 1000, replacing or partially replacing fuel or natural gas to provide driving power for the vehicle 1000.

[0141] Please refer to Figure 2 , Figure 2 This is an exploded view of a battery device 100 provided in some embodiments of this application. The battery device 100 may include a housing 10 and battery cells 20, the housing 10 being used to house the battery cells 20.

[0142] The housing 10 has an enclosed space inside for accommodating the battery cells 20. The housing 10 can have various structures. In some embodiments, the housing 10 may include a first housing body 11 and a second housing body 12, which are interlocked. The first housing body 11 and the second housing body 12 can have various shapes, such as cuboids or cylinders. The first housing body 11 can be a hollow structure open on one side, and the second housing body 12 can also be a hollow structure open on one side. The open side of the second housing body 12 interlocks with the open side of the first housing body 11, thus forming a housing 10 with an enclosed space. Alternatively, the first housing body 11 can be a hollow structure open on one side, and the second housing body 12 can be a plate-like structure, with the second housing body 12 interlocked with the open side of the first housing body 11, thus forming a housing 10 with an accommodating space.

[0143] In the battery device 100, there can be one or more battery cells 20. If there are multiple battery cells 20, they can be connected in series, parallel, or in a mixed configuration. A mixed configuration means that multiple battery cells 20 are connected in both series and parallel. Alternatively, multiple battery cells 20 can be first connected in series, parallel, or in a mixed configuration to form a battery module, and then multiple battery modules can be connected in series, parallel, or in a mixed configuration to form a whole, which is then housed within the housing 10. Another option is that all battery cells 20 can be directly connected in series, parallel, or in a mixed configuration, and then the whole consisting of all battery cells 20 is housed within the housing 10.

[0144] In some embodiments, the battery device 100 may further include a busbar component, through which multiple battery cells 20 can be electrically connected to each other to achieve series, parallel, or mixed connection of the multiple battery cells 20. The busbar component may be a metallic conductor, such as copper, iron, aluminum, stainless steel, aluminum alloy, etc.

[0145] Please refer to Figure 3, Figure 4 , Figure 5 and Figure 6 , Figure 3 This is a schematic diagram of the structure of a battery cell 20 provided in some embodiments of this application. Figure 4 An exploded view of a battery cell 20 provided in some embodiments of this application. Figure 5 This is a schematic diagram of the connection between the first insulating member 23 and the second insulating member 24 provided in some embodiments of this application. Figure 6 Exploded views of a first insulating member 23 and a second insulating member 24 provided in some embodiments of this application. Embodiments of this application provide a battery cell 20, which includes a housing 21, an electrode assembly 22, a first insulating member 23, and a second insulating member 24. The housing 21 has a first wall portion 213, and the electrode assembly 22 is housed within the housing 21. The electrode assembly 22 includes a tab 222 and a body portion 221, with the tab 222 disposed at one end of the body portion 221. The first insulating member 23 is at least partially disposed between the electrode assembly 22 and the first wall portion 213, and serves to insulate and isolate the electrode assembly 22 and the first wall portion 213. The second insulating member 24 is at least partially disposed between the body portion 221 and the first insulating member 23, and is connected to the first insulating member 23. The material damage temperature of the second insulating member 24 is greater than the material damage temperature of the first insulating member 23.

[0146] Battery cell 20 refers to the smallest unit that makes up battery device 100.

[0147] The housing 21 includes an end cap 211 and a housing 212. The housing 212 has a receiving space with an opening at one end for accommodating the electrode assembly 22. The end cap 211 is connected to the housing 212 and closes the opening.

[0148] End cap 211 refers to a component that covers the opening of housing 212 to isolate the internal environment of battery cell 20 from the external environment. The shape of end cap 211 can be adapted to the shape of housing 212 to fit it. Optionally, end cap 211 can be made of a material with certain hardness and strength (such as aluminum alloy), so that end cap 211 is not easily deformed under pressure and impact, allowing battery cell 20 to have higher structural strength and improved safety performance. The material of end cap 211 can also be various, such as copper, iron, aluminum, stainless steel, aluminum alloy, plastic, etc., and this application embodiment does not impose any special limitations on this. The housing 21 is also provided with electrode terminals 25, which are used for electrical connection with the tabs 222 of electrode assembly 22 to input or output electrical energy of battery cell 20. Electrode terminals 25 and tabs 222 can be directly connected, for example, electrode terminals 25 and tabs 222 can be directly welded. Electrode terminal 25 and electrode tab 222 can also be indirectly connected, for example, electrode terminal 25 and electrode tab 222 can be indirectly connected through current collector 26.

[0149] The housing 212 is a component used to cooperate with the end cap 211 to form the internal environment of the battery cell 20. This internal environment can accommodate the electrode assembly 22, electrolyte, and other components. The housing 212 and the end cap 211 can be independent components. An opening can be provided on the housing 212, and the end cap 211 can be used to close 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 mating surface before other components are inserted into the housing. When it is necessary to encapsulate the interior of the housing 212, the end cap 211 closes the housing 212. The housing 212 can have various shapes and sizes, such as cuboid or hexagonal prism. Specifically, the shape of the housing 212 can be determined according to the specific shape and size of the electrode assembly 22. The material of the housing 212 can include, but is not limited to, copper, iron, aluminum, stainless steel, aluminum alloy, and plastic.

[0150] In some embodiments, the housing 212 may have an opening at only one end, with one end cap 211 correspondingly provided. In other embodiments, the housing 212 may have openings at both ends, with two end caps 211 correspondingly provided, the two end caps 211 respectively closing the two opposite openings of the housing 212. Figure 3 and Figure 4 In the embodiment shown, the housing 212 has an opening at only one end, and an end cap 211 is provided accordingly.

[0151] Electrode assembly 22 is the component in the battery cell 20 where electrochemical reactions occur. The casing 21 may contain one or more electrode assemblies 22. The electrode assembly 22 is mainly formed by winding or stacking positive electrode plates 2212 and negative electrode plates 2214, and typically a separator 2213 is provided between the positive electrode plate 2212 and the negative electrode plate 2214. The portions of the positive electrode plate 2212 and the negative electrode plate 2214 containing active material constitute the main body 221 of the electrode assembly 22, while the portions of the positive electrode plate 2212 and the negative electrode plate 2214 without active material each constitute a tab 222. The positive and negative tabs may be located together at one end of the main body or at opposite ends of the main body 221. During the charging and discharging process of the battery cell 20, the positive and negative active materials react with the electrolyte.

[0152] The first wall portion 213 can be an end cap 211 of the outer casing 21, or it can be a wall portion of the housing 212 of the outer casing 21. In some embodiments, in Figure 3 and Figure 4In this embodiment, 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 housing 212 opposite to the end cap 211. In still other embodiments, the first wall portion 213 may also be a side wall of the housing 212 adjacent to and connected to the end cap 211.

[0153] The first insulating member 23 may be partially or wholly disposed between the electrode assembly 22 and the first wall portion 213. The first insulating member 23 is used to insulate and isolate the electrode assembly 22 and the first wall portion 213 to reduce the risk of short circuit. Please refer to... Figure 3 and Figure 4 In the embodiment shown in the figure, the first wall portion 213 is an end cap 211, and the first insulating member 23 is a lower plastic material. In other embodiments, the first wall portion 213 is the bottom wall of the housing 212 opposite to the end cap 211, and the first insulating member 23 can be a bottom support plate or a Mylar membrane. In still other embodiments, the first wall portion 213 is the side wall of the housing 212 adjacent to and connected to the end cap 211, and the first insulating member 23 can be a Mylar membrane. Exemplarily, the material of the first insulating member 23 can be plastic, rubber, etc.

[0154] The second insulating member 24 may be partially or wholly disposed between the main body 221 and the first insulating member 23. During normal use of the battery cell 20, both the first insulating member 23 and the second insulating member 24 serve to insulate and isolate the main body 221 and the first wall portion 213. The second insulating member 24 is connected to the first insulating member 23 to limit the relative positions of the second insulating member 24 and the first insulating member 23, and the second insulating member 24 and the main body 221. The second insulating member 24 may be adhered to the first insulating member 23, or it may be snapped onto the first insulating member 23. For example, the material of the second insulating member 24 may be plastic, rubber, etc.

[0155] The material damage temperature of a substance can be either its melting point or its decomposition temperature. A substance undergoes a decomposition reaction at a certain temperature; that temperature is the decomposition temperature. If a substance has both a melting point and a decomposition temperature, the decomposition temperature is its material damage temperature. If a substance only has a melting point and no decomposition temperature, the melting point is its material damage temperature. If a substance only has a decomposition temperature and no melting point, the decomposition temperature is its material damage temperature.

[0156] The material damage temperature of the second insulating component 24 is greater than that of the first insulating component 23. When the battery cell 20 experiences thermal runaway, the first insulating component 23 will reach the material damage temperature first and melt. When the first insulating component 23 melts, the second insulating component 24 can continue to insulate and isolate the main body 221 and the first wall 213, reducing the risk of short circuit when the main body 221 comes into contact with the first wall 213.

[0157] 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 can insulate and isolate the main body 221 and the first wall 213, reducing the risk of a short circuit due to contact between the main body 221 and the first wall 213. Since the material damage temperature of the second insulating member 24 is higher than that of the first insulating member 23, when another battery cell 20 adjacent to this 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, to a certain extent, insulate and isolate the main body 221 and the first wall 213, reducing the risk of a short circuit due to contact between the main body 221 and the first wall 213. Thus, even if another battery cell 20 adjacent to this battery cell 20 experiences thermal runaway, it is less likely to cause a short circuit in that battery cell 20 and further thermal runaway, which helps limit heat diffusion and improves the reliability of the battery cell 20. In addition, when another battery cell 20 adjacent to the battery cell 20 experiences thermal runaway, causing the first insulating member 23 of the battery cell 20 to melt, the second insulating member 24 can, to a certain extent, prevent the high-temperature melt generated after the first insulating member 23 melts from dripping onto the main body 221, reducing the risk of the main body 221 being burned and further causing thermal runaway, which is beneficial to improving the reliability of the battery cell 20.

[0158] Please refer to Figure 3 , Figure 4 , Figure 5 and Figure 6 In some embodiments, the first insulating member 23 includes a body portion 231 and a protrusion 232. The body portion 231 is at least partially disposed between the electrode assembly 22 and the first wall portion 213, and the protrusion 232 protrudes from the body portion 231 in a direction facing the electrode assembly 22. The protrusion 232 is disposed opposite to the body portion 221 along the thickness direction of the first wall portion 213. The second insulating member 24 is at least partially disposed between the body portion 221 and the protrusion 232, and is connected to the protrusion 232.

[0159] The body portion 231 is the main body of the first insulating member 23. The body portion 231 is partially or entirely disposed between the electrode assembly 22 and the first wall portion 213, serving to insulate and isolate the electrode assembly 22 and the first wall portion 213. Please refer to... Figure 5 ,exist Figure 5 In the embodiment shown, the body portion 231 has a flat plate structure.

[0160] The protrusion 232 is the portion of the first insulating member 23 that protrudes from the surface of the body portion 231 facing the electrode assembly 22. Along the thickness direction of the first wall portion 213, the protrusion 232 is disposed opposite to the body portion 221, and the protrusion 232 is closer to the body portion 221 than the body portion 231, allowing the protrusion 232 to abut against the body portion 221, thereby limiting the range of motion of the body portion 221 within the housing 21 to some extent. Please refer to... Figure 5 The thickness direction of the first wall portion 213 is the X direction shown in the figure.

[0161] The second insulating member 24 may be partially or wholly disposed between the main body portion 221 and the protrusion portion 232. The second insulating member 24 may be connected to the surface of the protrusion portion 232 facing the main body portion 221, or the second insulating member 24 may be connected to at least one side of the protrusion portion 232.

[0162] The body portion 231 is at least partially disposed between the electrode assembly 22 and the first wall portion 213. During normal use, both the body portion 231 and the second insulating member 24 can insulate and isolate the body portion 221 and the first wall portion 213, reducing the risk of short circuit due to contact between the body portion 221 and the first wall portion 213. The protrusion 232 protrudes from the body portion 231 in the direction facing the electrode assembly 22, and the protrusion 232 is disposed opposite to the body portion 221 in the thickness direction of the first wall portion 213, so that the protrusion 232 can restrict the range of motion of the body portion 221 within the housing 21. Since the protrusion 232 is closer to the main body 221 than the body 231, when another battery cell 20 adjacent to the battery cell 20 experiences thermal runaway, causing the first insulating member 23 of the battery cell 20 to melt, the protrusion 232 is more likely to damage the main body 221. By at least partially disposing the second insulating member 24 between the main body 221 and the protrusion 232 and connecting it to the protrusion 232, the second insulating member 24 can better prevent the high-temperature melt generated after the first insulating member 23 melts from dripping onto the main body 221, reducing the risk of the main body 221 being burned and further causing thermal runaway, which is beneficial to improving the reliability of the battery cell 20.

[0163] In some embodiments, the protrusion 232 presses against the main body 221 via the second insulating member 24.

[0164] Along the thickness direction of the first wall portion 213, the second insulating member 24 is at least partially located between the protrusion 232 and the main body portion 221. One side of the portion of the second insulating member 24 located between the protrusion 232 and the main body portion 221 contacts the main body portion 221, and the other side of the portion of the second insulating member 24 located between the protrusion 232 and the main body portion 221 contacts the protrusion 232.

[0165] "The protrusion 232 presses against the main body 221 through the second insulating member 24", that is, the protrusion 232 indirectly presses against the main body 221. Along the thickness direction of the first wall portion 213, the protrusion 232 can apply a compressive force to the main body 221 to confine the main body 221 within the outer shell 21.

[0166] The protrusion 232 presses against the main body 221 via the second insulating member 24. On the one hand, this restricts the movement of the main body 221 in the thickness direction of the first wall portion 213, which helps improve the reliability of the connection between the main body 221 and other electrical connection components and reduces the risk of damage to the main body 221. On the other hand, the main body 221 can support the second insulating member 24 to a certain extent, which helps to keep the second insulating member 24 between the main body 221 and the first insulating member 23. In this way, when another battery cell 20 adjacent to the battery cell 20 experiences thermal runaway, causing the first insulating member 23 of the battery cell 20 to melt, the second insulating member 24 can better prevent the high-temperature melt generated after the first insulating member 23 melts from dripping onto the main body 221, reducing the risk of the main body 221 being burned and further triggering thermal runaway, which helps to improve the reliability of the battery cell 20.

[0167] Please refer to Figure 7 and Figure 8 , Figure 7 A schematic diagram showing the connection between the first insulating member 23 and the second insulating member 24, provided for other embodiments of this application. Figure 8 Exploded views of a first insulating member 23 and a second insulating member 24 provided for other embodiments of this application. In other embodiments, the second insulating member 24 includes a first insulating portion 241 and a second insulating portion 242, the first insulating portion 241 being connected to the surface of the protrusion 232 facing the main body portion 221, and the second insulating portion 242 being connected to the surface of the body portion 231 facing the main body portion 221.

[0168] The first insulating portion 241 is the part of the second insulating member 24 connected to the surface of the protrusion 232 facing the main body portion 221. The first insulating portion 241 is at least partially located between the protrusion 232 and the main body portion 221. The first insulating portion 241 can prevent the high-temperature melt generated after the protrusion 232 melts from dripping onto the main body portion 221.

[0169] The second insulating portion 242 is the portion of the second insulating member 24 connected to the surface of the body portion 231 facing the main body portion 221. The second insulating portion 242 is at least partially located between the body portion 231 and the main body portion 221. The second insulating portion 242 can prevent the high-temperature melt generated after the body portion 231 melts from dripping onto the main body portion 221.

[0170] The first insulating part 241 may be connected to the second insulating part 242, or the first insulating part 241 may not be connected to the second insulating part 242.

[0171] When another battery cell 20 adjacent to the battery cell 20 experiences thermal runaway, causing the first insulating part 23 of the battery cell 20 to melt, the first insulating part 241 can prevent the high-temperature melt generated after the protrusion 232 melts from dripping onto the main body part 221, and the second insulating part 242 can prevent the high-temperature melt generated after the main body part 231 melts from dripping onto the main body part 221, thereby reducing the risk of the main body part 221 being burned and further causing thermal runaway, which is beneficial to improving the reliability of the battery cell 20.

[0172] Please refer to Figure 7 and Figure 8 In some embodiments, the first insulating part 241 and the second insulating part 242 are separately provided and not connected to each other.

[0173] The first insulating part 241 and the second insulating part 242 are two separate parts. The first insulating member 23 and the second insulating member 24 are not connected to each other. For example, the first insulating part 241 can be an insulating film that is pasted on the protrusion 232, and the second insulating part 242 can be another insulating film that is pasted on the body part 231.

[0174] By separating the first insulating part 241 and the second insulating part 242 and not connecting them to each other, the first insulating part 241 can be connected to the protrusion 232 and the second insulating part 242 can be connected to the body part 231 respectively, making assembly simpler and more convenient.

[0175] Please refer to Figure 9 and Figure 10 , Figure 9 This is a schematic diagram of the connection between the first insulating member 23 and the second insulating member 24, provided for some embodiments of this application. Figure 10 Exploded views of a first insulating member 23 and a second insulating member 24 provided for further embodiments of this application. In further embodiments, the second insulating member 24 includes a third insulating portion 243, which connects to the first insulating portion 241 and the second insulating portion 242.

[0176] The third insulating portion 243 is the part of the second insulating member 24 that connects the first insulating portion 241 and the second insulating portion 242. The third insulating portion 243 may or may not be connected to the first insulating member 23. Please refer to [reference needed]. Figure 9 and Figure 10 In the embodiment shown in the figure, the third insulating portion 243 is connected to one side of the protrusion 232.

[0177] By providing a third insulating portion 243 to connect the first insulating portion 241 and the second insulating portion 242, the overall integrity of the second insulating member 24 can be improved. Furthermore, along the thickness direction of the first wall portion 213, the second insulating member 24 can cover a larger area of ​​the first insulating member 23. When another battery cell 20 adjacent to this 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 better insulate and isolate the main body portion 221 and the first wall portion 213, and also better prevent the high-temperature molten material generated after the first insulating member 23 melts from dripping onto the main body portion 221, thus improving the reliability of the battery cell 20.

[0178] Please refer to Figure 9 and Figure 10 In some embodiments, the first insulating portion 241, the second insulating portion 242, and the third insulating portion 243 are integrally formed.

[0179] The first insulating part 241, the second insulating part 242, and the third insulating part 243 are an integral structure. For example, the second insulating member 24 is an insulating film, and the first insulating part 241, the second insulating part 242, and the third insulating part 243 are three parts formed by bending the second insulating member 24 twice.

[0180] By integrally molding the first insulating portion 241, the second insulating portion 242, and the third insulating portion 243, the second insulating member 24 achieves better overall integrity. Furthermore, even if one of the first insulating portion 241, the second insulating portion 242, or the third insulating portion 243 separates from the first insulating member 23, the separated portion can be held between the first insulating member 23 and the main body portion 221 by the action of the other portions, thereby insulatingly isolating the main body portion 221 and the first wall portion 213 when the first insulating member 23 melts.

[0181] Please refer to Figure 11 and Figure 12 In some embodiments, Figure 11 This is a schematic diagram of the connection between the first insulating member 23 and the second insulating member 24 provided in some embodiments of this application. Figure 12 Exploded views of a first insulating member 23 and a second insulating member 24 provided for further embodiments of this application. A battery cell 20 includes electrode terminals 25 disposed on a housing 21. The battery cell 20 includes a current collector 26 connecting the electrode terminals 25 and tabs 222. Along the thickness direction of the first wall portion 213, the second insulating member 24 is partially disposed opposite to the body portion 231, and the current collector 26 is at least partially disposed between the body portion 231 and the second insulating member 24.

[0182] Electrode terminals 25 are used for electrical connection with tabs 222 of electrode assembly 22 to input or output electrical energy of battery cell 20. The structure of electrode terminals 25 mounted on housing 21 can be varied. Exemplarily, both electrode terminals 25 are mounted on end caps 211 of housing 21. Of course, the structure of battery cell 20 is not limited to this. In other embodiments, both electrode terminals 25 may be mounted on housing 212 of housing 21. Similarly, one electrode terminal 25 may be mounted on housing 212 of housing 21, and the other electrode terminal 25 may be mounted on end cap 211 of housing 21.

[0183] The current collector 26 is used to connect the electrode terminal 25 and the electrode assembly 22 to realize the electrical connection between the electrode terminal 25 and the electrode assembly 22, which helps to reduce the assembly difficulty between the electrode terminal 222 and the electrode terminal 25.

[0184] Along the thickness direction of the first wall portion 213, a portion of the second insulating member 24 is disposed opposite to and connected to the protrusion 232, and another portion of the second insulating member 24 is disposed opposite to the body portion 231. A cavity is formed between the other portion of the second insulating member 24 and the body portion 231, and the current collecting member 26 can be partially or completely accommodated in the cavity, such that the current collecting member 26 is at least partially disposed between the body portion 231 and the second insulating member 24.

[0185] The current collector 26 connects the electrode terminal 25 and the tab 222, enabling the electrode terminal 25 to output electrical energy to or input electrical energy to the electrode assembly 22. Along the thickness direction of the first wall portion 213, a portion of the second insulating member 24 is disposed between the body portion 231 and the main body portion 221, and another portion is disposed between the protrusion 232 and the main body portion 221. When another battery cell 20 adjacent to this 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 both insulate and isolate the main body portion 221 and the first wall portion 213, and prevent the high-temperature molten material generated after the first insulating member 23 melts from dripping onto the main body portion 221, thus improving the reliability of the battery cell 20. Furthermore, since the current collector 26 is at least partially disposed between the body portion 231 and the second insulating member 24, the second insulating member 24 can also reduce the risk of a short circuit caused by the current collector 26 inserting into the main body portion 221 when the main body portion 221 shifts.

[0186] Please refer to Figure 13 , Figure 14 and Figure 15 , Figure 13 Exploded view of a battery cell 20 provided for other embodiments of this application. Figure 14 This is a top view of a battery cell 20 provided in some other embodiments of this application. Figure 15 for Figure 14 A cross-sectional view at position AA. In some embodiments, the second insulating member 24 includes a first insulating portion 241 and a second insulating portion 242. Along the thickness direction of the first wall portion 213, the first insulating portion 241 is at least partially disposed between the main body portion 221 and the first insulating member 23, and is connected to the first insulating member 23. Along a first direction, the main body portion 221 has two opposing first surfaces 2211, and the second insulating portion 242 is connected to one of the first surfaces 2211. The first direction is perpendicular to the thickness direction of the first wall portion 213.

[0187] The first direction is perpendicular to the thickness direction of the first wall portion 213. Please refer to... Figure 13 and Figure 15 The first direction is the Y direction shown in the figure.

[0188] The first insulating portion 241 is the portion of the second insulating member 24 disposed between the main body portion 221 and the first insulating member 23 along the thickness direction of the first wall portion 213, to insulatingly isolate the main body portion 221 and the first wall portion 213. The first insulating portion 241 is connected to the first insulating member 23 to limit the relative positions of the first insulating portion 241 and the first insulating member 23, and the first insulating portion 241 and the main body portion 221. In some embodiments, a portion of the first insulating portion 241 is disposed between the main body portion 221 and the first insulating member 23 along the thickness direction of the first wall portion 213. In other embodiments, the entire first insulating portion 241 is disposed between the main body portion 221 and the first insulating member 23 along the thickness direction of the first wall portion 213.

[0189] The second insulating portion 242 is a portion of the second insulating member 24 disposed on one side of the main body portion 221 along the first direction. The main body portion 221 has two first surfaces 2211 disposed opposite to each other along the first direction, and the second insulating portion 242 is connected to the first surfaces 2211.

[0190] The first insulating part 241 is connected to the second insulating part 242. Optionally, the first insulating part 241 and the second insulating part 242 are integrally formed.

[0191] The first insulating portion 241 is at least partially disposed between the main body portion 221 and the first insulating member 23 along the thickness direction of the first wall portion 213. During normal use, both the first insulating member 23 and the first insulating portion 241 can insulate and isolate the main body portion 221 and the first wall portion 213, reducing the risk of a short circuit due to contact between the main body portion 221 and the first wall portion 213. Since the material damage temperature of the second insulating member 24 is greater than that of the first insulating member 23, when another battery cell 20 adjacent to this battery cell 20 experiences thermal runaway, causing the first insulating member 23 of that battery cell 20 to melt, the first insulating portion 241 can still, to a certain extent, insulate and isolate the main body portion 221 and the first wall portion 213, reducing the risk of a short circuit due to contact between the main body portion 221 and the first wall portion 213. Furthermore, when another battery cell 20 adjacent to the first insulating member 23 of the first insulating member 20 experiences thermal runaway, causing the first insulating portion 241 to melt, it can, to a certain extent, prevent the high-temperature molten material generated by the melting of the first insulating member 23 from dripping onto the main body 221. This reduces the risk of the main body 221 being burned and further triggering thermal runaway, thus improving the reliability of the battery cell 20. The second insulating portion 242 is connected to the first surface 2211. On the one hand, it restricts the relative positions of the first insulating portion 241 and the main body 221, and the second insulating portion 242 and the main body 221, to a certain extent. This allows the first insulating portion 241 to be more stably positioned between the main body 221 and the first insulating member 23, thereby insulating and isolating the main body 221 and the first wall portion 213 and preventing the high-temperature molten material generated by the melting of the first insulating member 23 from dripping onto the main body 221, which is beneficial to improving the reliability of the battery cell 20. On the other hand, the second insulating portion 242 can reduce the risk of short circuits caused by the first surface 2211 contacting other components, which is beneficial to improving the reliability of the battery cell 20.

[0192] Please refer to Figure 13 , Figure 14 and Figure 15 In some embodiments, the outer casing 21 includes a second wall portion 2121 connected to the first wall portion 213, and the second wall portion 2121 is the wall portion with the largest outer surface area in the outer casing 21. Along the first direction, the second insulating portion 242 is at least partially located between the main body portion 221 and the second wall portion 2121.

[0193] The second wall portion 2121 is the wall portion with the largest outer surface area in the outer shell 21, commonly referred to as the large surface. The first wall portion 213 is adjacent to the second wall portion 2121. Please refer to... Figure 13 and Figure 15 In the embodiment shown in the figure, the first wall portion 213 is an end cap 211. In other embodiments, the first wall portion 213 may also be the bottom wall of the housing 212.

[0194] A second insulating portion 242 is disposed between the main body portion 221 and the second wall portion 2121 along a first direction, and the second insulating portion 242 is capable of insulating and isolating the main body portion 221 and the second wall portion 2121. In some embodiments, a portion of the second insulating portion 242 is disposed between the main body portion 221 and the second wall portion 2121 along the first direction. In other embodiments, the entire second insulating portion 242 is disposed between the main body portion 221 and the second wall portion 2121 along the first direction.

[0195] The second insulating portion 242 is located at least partially between the main body portion 221 and the second wall portion 2121 along the first direction to insulate the main body portion 221 and the second wall portion 2121. Because the material damage temperature of the second insulating member 24 is relatively high, when another battery cell 20 adjacent to this battery cell 20 experiences thermal runaway, the second insulating portion 242 can still, to a certain extent, insulate the main body portion 221 and the second wall portion 2121, reducing the risk of a short circuit due to contact between the main body portion 221 and the second wall portion 2121. Thus, even if another battery cell 20 adjacent to this battery cell 20 experiences thermal runaway, it is less likely to cause a short circuit in that battery cell 20, further leading to thermal runaway, which helps limit heat diffusion and improves the reliability of the battery cell 20. Furthermore, since the second wall portion 2121 has the largest outer surface area in the outer casing 21, when another battery cell 20 adjacent to this battery cell 20 experiences thermal runaway, heat can easily be transferred from the second wall portion 2121 to the main body portion 221, causing the insulating member 2213 of the main body portion 221 to shrink due to heat. The second insulating part 242 can prevent heat from being transferred to the main body 221 to a certain extent, thereby reducing the risk of the separator 2213 shrinking due to high temperature, making the positive electrode 2212 and the negative electrode 2214 less likely to be exposed, which is beneficial to improving the reliability of the battery cell 20.

[0196] Please refer to Figure 16 and Figure 17 , Figure 16 An exploded view of a battery cell 20 provided for some embodiments of this application. Figure 17 This is a cross-sectional view of a battery cell 20 provided in some embodiments of this application. In some embodiments, each electrode assembly 22 is provided with at least one second insulating member 24. The second insulating member 24 includes two second insulating portions 242, a first insulating portion 241 connecting the two second insulating portions 242, and the two second insulating portions 242 are respectively connected to two first surfaces 2211 of the main body portion 221.

[0197] The correspondence between the electrode assembly 22 and the second insulating member 24 can be one-to-one, meaning that there is a one-to-one correspondence between the electrode assembly 22 and the second insulating member 24. Alternatively, the correspondence can be one-to-many, meaning that one electrode assembly 22 can be provided with multiple second insulating members 24. For example, one electrode assembly 22 can be provided with two, three, four, or more second insulating members 24.

[0198] Each second insulating element 24 includes a first insulating portion 241 and two second insulating portions 242. The first insulating portion 241 connects to the two second insulating portions 242. The two second insulating portions 242 are arranged opposite to each other along a first direction. The two second insulating portions 242 are respectively connected to two first surfaces 2211 of the main body portion 221 of an electrode assembly 22.

[0199] Each electrode assembly 22 is provided with at least one second insulating member 24. The two second insulating portions 242 of each second insulating member 24 are respectively connected to the two first surfaces 2211 of the main body 221, so that each electrode assembly 22 can be well protected. Furthermore, during manufacturing, each second insulating member 24 can be individually connected to each electrode assembly 22 and the first insulating member 23, which helps to reduce production difficulty.

[0200] Please refer to Figure 18 , Figure 18 This is a cross-sectional view of a battery cell 20 provided in some embodiments of this application. In some embodiments, the battery cell 20 includes a plurality of electrode assemblies 22 stacked along a first direction. Along the first direction, in two adjacent second insulating members 24, a second insulating portion 242 of one second insulating member 24 is connected to a second insulating portion 242 of the other second insulating member 24.

[0201] The battery cell 20 may include two electrode assemblies 22, three electrode assemblies 22, four electrode assemblies 22, or more electrode assemblies 22. The multiple electrode assemblies 22 are stacked along a first direction.

[0202] Each electrode assembly 22 is provided with at least one second insulating member 24, and a plurality of second insulating members 24 are arranged along a first direction. In two adjacent second insulating members 24, a second insulating portion 242 of one second insulating member 24 is located between the two adjacent electrode assemblies 22, and the second insulating portion 242 of one second insulating member 24 is connected to the second insulating portion 242 of the other second insulating member 24.

[0203] Optionally, a second insulating portion 242 of one second insulating member 24 is bonded to a second insulating portion 242 of another second insulating member 24.

[0204] By connecting one second insulating portion 242 of one second insulating member 24 to one second insulating portion 242 of another second insulating member 24, adjacent second insulating members 24 can be connected together. In this way, even if the connection between one of the multiple second insulating members 24 and the electrode assembly 22 and / or the first insulating member 23 fails, the relative position of the second insulating member 24 and the electrode assembly 22 can be maintained to a certain extent. This allows the second insulating member 24 to insulate and isolate its corresponding electrode assembly 22 and the first wall portion 213, and prevents the high-temperature melt generated after the first insulating member 23 melts from dripping onto the main body portion 221, which is beneficial to improving the reliability of the battery cell 20.

[0205] Please refer to Figure 19 and Figure 20 , Figure 19 An exploded view of a battery cell 20 provided in some embodiments of this application. Figure 20 This application also provides cross-sectional views of battery cell 20 according to some embodiments. In other embodiments, battery cell 20 includes a plurality of electrode assemblies 22 stacked along a first direction, wherein two electrode assemblies 22 located at opposite ends of the first direction are a first electrode assembly 223 and a second electrode assembly 224, respectively. The second insulating member 24 includes two second insulating portions 242, one second insulating portion 242 being connected to a first surface 2211 of the first electrode assembly 223 facing away from the second electrode assembly 224, and the other second insulating portion 242 being connected to a first surface 2211 of the second electrode assembly 224 facing away from the first electrode assembly 223.

[0206] The battery cell 20 may include two, three, four, or more electrode assemblies 22. The multiple electrode assemblies 22 are stacked along a first direction. Among the multiple electrode assemblies 22, the two electrode assemblies 22 located at opposite ends of the first direction are respectively the first electrode assembly 223 and the second electrode assembly 224.

[0207] The second insulating member 24 includes a first insulating portion 241 and two second insulating portions 242. The first insulating portion 241 connects to the two second insulating portions 242, which are disposed opposite to each other along a first direction. The two second insulating portions 242 are respectively connected to the first electrode assembly 223 and the second electrode assembly 224. Specifically, along the first direction, one second insulating portion 242 is connected to a first surface 2211 of the first electrode assembly 223 facing away from the second electrode assembly 224, and the other second insulating portion 242 is connected to a first surface 2211 of the second electrode assembly 224 facing away from the first electrode assembly 223. Along the thickness direction of the first wall portion 213, the first insulating portion 241 is located between the main body portion 221 of the plurality of electrode assemblies 22 and the first wall portion 213.

[0208] Along the thickness direction of the first wall portion 213, a second insulating member 24 is located between the main body portion 221 of the plurality of electrode assemblies 22 and the first insulating member 23. The second insulating member 24 can not only achieve insulation isolation between the main body portion 221 of the plurality of electrode assemblies 22 and the first wall portion 213, providing good insulation effect, but also prevent the high-temperature molten material generated after the first insulating member 23 melts from dripping onto the main body portion 221, which is beneficial to improving the reliability of the battery cell 20. Furthermore, the location of the second insulating member 24 between the main body portion 221 of the plurality of electrode assemblies 22 and the first insulating member 23 also helps to reduce the space occupied inside the casing 21, which is beneficial to improving the energy density of the battery cell 20.

[0209] Please refer to Figure 19 , Figure 20 and Figure 21 , Figure 21 This is a schematic diagram of the structure of an electrode assembly 22 provided in some embodiments of this application. The electrode assembly 22 includes a positive electrode, an insulating member 2213, and a negative electrode, which are wound or stacked. The first surface 2211 is the surface of the insulating member 2213.

[0210] The first surface 2211 is the outer surface of the outermost insulating member 2213, and the second insulating part 242 is connected to the first surface 2211.

[0211] By connecting the second insulating portion 242 to the surface of the separator 2213, on the one hand, it helps to fix the separator 2213, maintain its shape, and reduce the risk of the separator 2213 shrinking due to high temperature. This makes the positive electrode 2212 and negative electrode 2214 less likely to be exposed, which helps to improve the reliability of the battery cell 20. On the other hand, the second insulating portion 242 can prevent heat from being transferred to the separator 2213 to a certain extent, thereby reducing the risk of the separator 2213 shrinking due to high temperature. This makes the positive electrode 2212 and negative electrode 2214 less likely to be exposed, which helps to improve the reliability of the battery cell 20.

[0212] Please refer to Figure 22 , Figure 22 Exploded views of the battery cell 20 provided in some embodiments of this application are also included. In some embodiments, the second insulating member 24 has a flat plate structure.

[0213] A flat plate structure refers to a structure enclosed by two parallel planes and a cylindrical or prismatic face perpendicular to these two parallel planes. Please refer to [reference needed]. Figure 22 The two parallel surfaces are arranged opposite each other along the thickness direction of the first wall portion 213.

[0214] The second insulating element 24 can be a rectangular plate structure, a hexagonal plate structure, a circular plate structure, an elliptical plate structure, etc.

[0215] The thickness of the second insulating element 24 can be set to be relatively small, so that the second insulating element 24 has a thin sheet structure.

[0216] When the second insulating member 24 has a flat plate structure, on the one hand, it is easier to manufacture the second insulating member 24 and reduce the cost of the second insulating member 24. On the other hand, the second insulating member 24 does not need to extend between the main body 221 and other wall parts, and it is less likely to form a stepped structure on the outside of the main body 221, thus reducing stress concentration in the electrode assembly 22.

[0217] Please refer to Figure 22 In some embodiments, each electrode assembly 22 is provided with at least one second insulating element 24.

[0218] The correspondence between the electrode assembly 22 and the second insulating member 24 can be one-to-one, meaning there is a one-to-one correspondence between the electrode assembly 22 and the second insulating member 24. Alternatively, the correspondence can be one-to-many, meaning one electrode assembly 22 can be provided with multiple second insulating members 24. For example, one electrode assembly 22 can be provided with two, three, four, or more second insulating members 24. Multiple second insulating members 24 are located between the main body portion 221 and the first wall portion 213 of the same electrode assembly 22.

[0219] Each electrode assembly 22 is provided with at least one second insulating element 24, so that each electrode assembly 22 can be well protected.

[0220] Please refer to this again. Figure 19 and Figure 20 In other embodiments, each second insulating member 24 is located between the body portion 221 of the plurality of electrode assemblies 22 and the first insulating member 23.

[0221] Each second insulating member 24 is disposed between the main body portion 221 and the first wall portion 213 of the plurality of electrode assemblies 22. Each second insulating member 24 can not only achieve insulation isolation between the main body portion 221 and the first wall portion 213 of the plurality of electrode assemblies 22, providing a good insulation effect, but also prevent the high-temperature molten material generated after the first insulating member 23 melts from dripping onto the main body portion 221. In other words, along the thickness direction of the first wall portion 213, the projection of the main body portion 221 of the plurality of electrode assemblies 22 overlaps with the projection of the second insulating member 24. The projection of the main body portion 221 of one electrode assembly 22 can be partially located within the projection of the second insulating member 24, and another part can be located outside the projection of the second insulating member 24. Alternatively, the projection of the main body portion 221 of one electrode assembly 22 can be entirely located within the projection of the second insulating member 24.

[0222] A second insulating member 24 not only provides insulation between the main body 221 and the first wall 213 of the multiple electrode assemblies 22, providing good insulation, but also prevents the high-temperature molten material generated after the first insulating member 23 melts from dripping onto the main body 221, thus improving the reliability of the battery cell 20. Furthermore, the second insulating member 24, located between the main body 221 and the first insulating member 23 of the multiple electrode assemblies 22, also helps reduce the space occupied inside the casing 21, thereby increasing the energy density of the battery cell 20.

[0223] Please refer to Figure 19 and Figure 20 In some embodiments, the main body 221 has a first end 2215 facing the first wall 213 along the thickness direction of the first wall 213. The electrode assembly 22 includes two tabs 222 with opposite polarities, both tabs 222 being disposed at the first end 2215. A first insulating member 23 is at least partially disposed between the first end 2215 and the first wall 213, and a second insulating member 24 is at least partially disposed between the first end 2215 and the first wall 213.

[0224] The electrode assembly 22 includes two tabs 222, one of which is a positive tab 222 and the other of which is a negative tab 222. The two tabs 222 are disposed at one end of the main body 221 facing the first wall portion 213.

[0225] The first insulating member 23 is at least partially disposed between the first end 2215 and the first wall portion 213, and the second insulating member 24 is at least partially disposed between the first end 2215 and the first wall portion 213. Thus, the first insulating member 23, the second insulating member 24, and the two tabs 222 are disposed at the same end of the main body portion 221.

[0226] The first insulating member 23, the second insulating member 24, and the two tabs 222 are disposed at the same end of the main body 221. During normal use, both the first insulating member 23 and the second insulating member 24 can insulate and isolate the main body 221 and the first wall 213, reducing the risk of short circuit due to contact between the main body 221 and the first wall 213. Since the material damage temperature of the second insulating member 24 is greater than that of the first insulating member 23, when another battery cell 20 adjacent to this 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 not only better insulate and isolate the main body 221 and the first wall 213, but also better prevent the high-temperature molten material generated after the first insulating member 23 melts from dripping onto the main body 221, which is beneficial to improving the reliability of the battery cell 20.

[0227] Please refer to Figure 19 and Figure 20 In some embodiments, two tabs 222 are spaced apart at the first end 2215 along a second direction. Along the second direction, a second insulating member 24 is provided on the side of one tab 222 opposite to the other tab 222.

[0228] The two tabs 222 are spaced apart along the second direction. Please refer to... Figure 19 The second direction can be the Z direction shown in the figure. In the embodiment shown in the figure, the first direction, the second direction, and the thickness direction of the first wall portion 213 are perpendicular to each other.

[0229] Please refer to Figure 19 ,exist Figure 19 In the illustrated embodiment, along the second direction, a second insulating member 24 is provided on the side of one electrode tab 222 opposite to the other electrode tab 222. Each electrode assembly 22 is provided with two corresponding second insulating members 24, which are located on both sides of the two electrode tabs 222 along the second direction.

[0230] Along the second direction, a second insulating member 24 may be provided on the side of one electrode 222 that is away from the other electrode 222. In this way, the second insulating member 24 is less likely to interfere with the electrode 222 and can better insulate and isolate the main body 221 and the first wall 213.

[0231] Please refer to Figure 19 and Figure 20 In some embodiments, the housing 21 includes a housing 212 and an end cap 211, the housing 212 having an opening and the end cap 211 closing the opening, the end cap 211 being a first wall portion 213. The first insulating member 23 is a lower plastic disposed on the side of the end cap 211 facing the electrode assembly 22.

[0232] End cap 211 is the first wall portion 213, and first insulating member 23 is the lower plastic. During normal use, both the lower plastic and the second insulating member 24 can insulate and isolate the main body portion 221 and the first wall portion 213, reducing the risk of short circuit due to contact between the main body portion 221 and the first wall portion 213. Since the material damage temperature of the second insulating member 24 is greater than that of the lower plastic, when another battery cell 20 adjacent to this battery cell 20 experiences thermal runaway, causing the lower plastic of that battery cell 20 to melt, the second insulating member 24 can better insulate and isolate the main body portion 221 and the first wall portion 213, and can also better prevent the high-temperature melt generated after the lower plastic melts from dripping onto the main body portion 221, which is beneficial to improving the reliability of the battery cell 20.

[0233] In some embodiments, the second insulating element 24 is an insulating film.

[0234] Optionally, the second insulating member 24 is a PI film (Polyimide Film) connected to the first insulating member 23.

[0235] The second insulating component 24 is an insulating film. The insulating film can effectively insulate and isolate the main body 221 and the first wall 213, and will not occupy too much space inside the outer casing 21, so that the battery cell 20 can still have a high energy density.

[0236] Please refer to Figure 19 and Figure 20 In some embodiments, the thickness of the insulating film is H, which satisfies: 0.01mm≤H≤0.5mm.

[0237] H represents the thickness of the insulating film. During measurement, multiple measurements can be taken and the average value can be used as H.

[0238] The thickness of the insulating film can be: H = 0.01mm, 0.05mm, 0.1mm, 0.15mm, 0.2mm, 0.25mm, 0.3mm, 0.35mm, 0.4mm, 0.45mm, 0.5mm, etc.

[0239] When H ≥ 0.01 mm, the insulating film has a relatively large thickness, making it less prone to breakage and exhibiting good mechanical properties and insulation performance. This effectively prevents the high-temperature molten material generated after the first insulating component 23 melts from dripping onto the main body 221. When H ≤ 0.5 mm, the insulating film thickness is not excessive, which helps reduce the space occupied by the battery cell 20 and improves the energy density of the battery cell 20. Therefore, when 0.01 mm ≤ H ≤ 0.5 mm, both the insulation performance of the insulating film and the energy density of the battery cell 20 can be balanced.

[0240] Optionally, 0.05mm ≤ H ≤ 0.2mm.

[0241] The thickness of the insulating film can be: H = 0.05mm, 0.06mm, 0.07mm, 0.08mm, 0.09mm, 0.1mm, 0.11mm, 0.12mm, 0.13mm, 0.14mm, 0.15mm, 0.16mm, 0.17mm, 0.18mm, 0.19mm, 0.2mm, etc.

[0242] When H ≥ 0.05 mm, the insulating film is thicker, less prone to breakage, and has better mechanical properties and insulation effect, effectively preventing the high-temperature molten material generated after the first insulating component 23 melts from dripping onto the main body 221. When H ≤ 0.2 mm, the insulating film thickness is not too large, which helps to reduce the space occupied by the battery cell 20 and improve the energy density of the battery cell 20. Therefore, when 0.05 mm ≤ H ≤ 0.2 mm, it is possible to better balance the insulation effect of the insulating film and the energy density of the battery cell 20.

[0243] In some embodiments, the material damage temperature of the second insulating element 24 is greater than or equal to 150°C.

[0244] By making the material damage temperature of the second insulating element 24 greater than or equal to 150°C, when another battery cell 20 adjacent to the battery cell 20 experiences thermal runaway, the second insulating element 24 is less likely to melt, thus enabling the second insulating element 24 to play an insulating and isolating role and reducing the risk of short circuit in the battery cell 20.

[0245] Optionally, the material damage temperature of the second insulating element 24 is greater than or equal to 250°C.

[0246] By making the material damage temperature of the second insulating element 24 greater than or equal to 250°C, when another battery cell 20 adjacent to the battery cell 20 experiences thermal runaway, the second insulating element 24 is less likely to melt, thus enabling the second insulating element 24 to play an insulating and isolating role and reducing the risk of short circuit in the battery cell 20.

[0247] In some embodiments, the material of the second insulating member 24 includes at least one of polyethylene terephthalate, polyphthalamide, polyphenylene sulfide, and polyimide.

[0248] Polyethylene terephthalate, polyphthalamide, polyphenylene sulfide, and polyimide have good high-temperature resistance and good insulation effect. They can insulate the body part 231 and the first wall part 213 when another battery cell 20 adjacent to the battery cell 20 experiences thermal runaway, thereby reducing the risk of short circuit of the battery cell 20 and improving the reliability of the battery cell 20.

[0249] This application embodiment also provides a battery device 100, which includes the aforementioned battery cell 20.

[0250] This application embodiment also provides an electrical device, which includes the aforementioned battery cell 20, and the battery cell 20 is used to provide electrical energy to the electrical device.

[0251] According to some embodiments of this application, please refer to Figures 3 to 22 .

[0252] This application provides a battery cell 20, which includes a housing 21, an electrode assembly 22, a first insulating member 23, and a second insulating member 24. The housing 21 has a first wall portion 213, and the electrode assembly 22 is housed within the housing 21. The electrode assembly 22 includes a tab 222 and a main body portion 221, with the tab 222 disposed at one end of the main body portion 221. The first insulating member 23 is at least partially disposed between the electrode assembly 22 and the first wall portion 213, and serves to insulate and isolate the electrode assembly 22 and the first wall portion 213. The second insulating member 24 is at least partially disposed between the main body portion 221 and the first insulating member 23, and is connected to the first insulating member 23. The material damage temperature of the second insulating member 24 is greater than the material damage temperature of the first insulating member 23. 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 can insulate and isolate the main body 221 and the first wall 213, reducing the risk of a short circuit due to contact between the main body 221 and the first wall 213. Since the material damage temperature of the second insulating member 24 is higher than that of the first insulating member 23, when another battery cell 20 adjacent to this 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, to a certain extent, insulate and isolate the main body 221 and the first wall 213, reducing the risk of a short circuit due to contact between the main body 221 and the first wall 213. Thus, even if another battery cell 20 adjacent to this battery cell 20 experiences thermal runaway, it is less likely to cause a short circuit in that battery cell 20 and further thermal runaway, which helps limit heat diffusion and improves the reliability of the battery cell 20. In addition, when another battery cell 20 adjacent to the battery cell 20 experiences thermal runaway, causing the first insulating member 23 of the battery cell 20 to melt, the second insulating member 24 can, to a certain extent, prevent the high-temperature melt generated after the first insulating member 23 melts from dripping onto the main body 221, reducing the risk of the main body 221 being burned and further causing thermal runaway, which is beneficial to improving the reliability of the battery cell 20.

[0253] The first insulating member 23 includes a body portion 231 and a protrusion 232. The body portion 231 is at least partially disposed between the electrode assembly 22 and the first wall portion 213, and the protrusion 232 protrudes from the body portion 231 in the direction facing the electrode assembly 22. Along the thickness direction of the first wall portion 213, the protrusion 232 is disposed opposite to the main body portion 221. The second insulating member 24 is at least partially disposed between the main body portion 221 and the protrusion 232, and is connected to the protrusion 232. The body portion 231 is at least partially disposed between the electrode assembly 22 and the first wall portion 213. During normal use, both the body portion 231 and the second insulating member 24 can insulate and isolate the main body portion 221 and the first wall portion 213, reducing the risk of a short circuit due to contact between the main body portion 221 and the first wall portion 213. The protrusion 232 protrudes from the body portion 231 in the direction facing the electrode assembly 22, and is disposed opposite to the main body portion 221 in the thickness direction of the first wall portion 213, so that the protrusion 232 can restrict the range of movement of the main body portion 221 within the housing 21. Since the protrusion 232 is closer to the main body portion 221 than the body portion 231, when another battery cell 20 adjacent to the battery cell 20 experiences thermal runaway, causing the first insulating member 23 of the battery cell 20 to melt, the protrusion 232 is more likely to damage the main body portion 221. By disposing at least partially between the main body portion 221 and the protrusion 232 and connecting it to the protrusion 232, the second insulating member 24 can better prevent the high-temperature melt generated after the first insulating member 23 melts from dripping onto the main body portion 221, reducing the risk of the main body portion 221 being burned and further causing thermal runaway, which is beneficial to improving the reliability of the battery cell 20.

[0254] The second insulating member 24 includes a first insulating portion 241 and a second insulating portion 242. The first insulating portion 241 is connected to the surface of the protrusion 232 facing the main body portion 221, and the second insulating portion 242 is connected to the surface of the main body portion 231 facing the main body portion 221. When another battery cell 20 adjacent to the battery cell 20 experiences thermal runaway, causing the first insulating member 23 of the battery cell 20 to melt, the first insulating portion 241 can prevent the high-temperature molten material generated after the protrusion 232 melts from dripping onto the main body portion 221, and the second insulating portion 242 can prevent the high-temperature molten material generated after the main body portion 231 melts from dripping onto the main body portion 221. This reduces the risk of the main body portion 221 being burned and further triggering thermal runaway, which is beneficial to improving the reliability of the battery cell 20.

[0255] In some embodiments, the first insulating portion 241 and the second insulating portion 242 are separately provided and not connected to each other. By providing the first insulating portion 241 and the second insulating portion 242 separately and not connecting them to each other, the first insulating portion 241 can be connected to the protrusion 232 and the second insulating portion 242 can be connected to the body portion 231 respectively, making assembly simpler and more convenient.

[0256] In other embodiments, the second insulating member 24 includes a third insulating portion 243, which connects the first insulating portion 241 and the second insulating portion 242. The first insulating portion 241, the second insulating portion 242, and the third insulating portion 243 are integrally formed. By providing the third insulating portion 243 to connect the first insulating portion 241 and the second insulating portion 242, on the one hand, the overall integrity of the second insulating member 24 can be improved. On the other hand, along the thickness direction of the first wall portion 213, the second insulating member 24 can cover more area of ​​the first insulating member 23. When another battery cell 20 adjacent to the battery cell 20 experiences thermal runaway, causing the first insulating member 23 of the battery cell 20 to melt, the second insulating member 24 can better insulate and isolate the main body portion 221 and the first wall portion 213, and can also better prevent the high-temperature molten material generated after the first insulating member 23 melts from dripping onto the main body portion 221, which is beneficial to improving the reliability of the battery cell 20. By integrally molding the first insulating portion 241, the second insulating portion 242, and the third insulating portion 243, the second insulating member 24 achieves better overall integrity. Furthermore, even if one of the first insulating portion 241, the second insulating portion 242, or the third insulating portion 243 separates from the first insulating member 23, the separated portion can be held between the first insulating member 23 and the main body portion 221 by the action of the other portions, thereby insulatingly isolating the main body portion 221 and the first wall portion 213 when the first insulating member 23 melts.

[0257] In some embodiments, the battery cell 20 includes electrode terminals 25 disposed on the housing 21. The battery cell 20 includes a current collector 26 connecting the electrode terminals 25 and tabs 222. Along the thickness direction of the first wall portion 213, a second insulating member 24 is partially disposed opposite to the body portion 231, and the current collector 26 is at least partially disposed between the body portion 231 and the second insulating member 24. The current collector 26 connects the electrode terminals 25 and the tabs 222, enabling the electrode terminals 25 to output electrical energy to or input electrical energy to the electrode assembly 22. Along the thickness direction of the first wall portion 213, a portion of the second insulating member 24 is disposed between the body portion 231 and the main body portion 221, and a portion of the second insulating member 24 is disposed between the protrusion 232 and the main body portion 221. When another battery cell 20 adjacent to this 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 both insulate and isolate the main body portion 221 and the first wall portion 213, and prevent the high-temperature molten material generated after the first insulating member 23 melts from dripping onto the main body portion 221, which helps to improve the reliability of the battery cell 20. In addition, the current collector 26 is at least partially disposed between the body portion 231 and the second insulating member 24. The second insulating member 24 can also reduce the risk of short circuit caused by the current collector 26 inserting into the main body portion 221 when the main body portion 221 moves.

[0258] The above description is merely a preferred embodiment of this application and is not intended to limit this application. Various modifications and variations can be made to this application by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this application should be included within the protection scope of this application.

Claims

1. A battery cell, characterized by, The battery cell comprises: a housing having a first wall portion; an electrode assembly accommodated in the housing, the electrode assembly comprising a tab and a main body portion, the tab being provided at one end of the main body portion; a first insulating member at least partially provided between the electrode assembly and the first wall portion, the first insulating member being configured to insulate the electrode assembly from the first wall portion; a second insulating member at least partially provided between the main body portion and the first insulating member, and connected to the first insulating member, the second insulating member having a material damage temperature greater than that of the first insulating member.

2. The battery cell of claim 1, wherein, The first insulating member comprises a body portion at least partially provided between the electrode assembly and the first wall portion, and a protruding portion protruding from the body portion in a direction facing the electrode assembly, the protruding portion being disposed opposite the main body portion in a thickness direction of the first wall portion, and the second insulating member being at least partially provided between the main body portion and the protruding portion, and connected to the protruding portion.

3. The battery cell of claim 2, wherein, The protruding portion is pressed against the main body portion by the second insulating member.

4. The battery cell of claim 2, wherein, The second insulating member comprises a first insulating portion connected to a surface of the protruding portion facing the main body portion, and a second insulating portion connected to a surface of the body portion facing the main body portion.

5. The battery cell of claim 4, wherein, The first insulating portion and the second insulating portion are separate and not connected to each other.

6. The battery cell of claim 4, wherein, The second insulating member comprises a third insulating portion connecting the first insulating portion and the second insulating portion.

7. The battery cell of claim 6, wherein, The first insulating portion, the second insulating portion, and the third insulating portion are integrally formed.

8. The battery cell of claim 2, wherein, The battery cell comprises an electrode terminal provided in the housing; The battery cell comprises a current collecting member connecting the electrode terminal and the tab; In the thickness direction of the first wall portion, the second insulating member is partially disposed opposite the body portion, and the current collecting member is at least partially provided between the body portion and the second insulating member.

9. The battery cell of claim 1, wherein, The second insulating member comprises a first insulating portion and a second insulating portion; In the thickness direction of the first wall portion, the first insulating portion is at least partially provided between the main body portion and the first insulating member, and connected to the first insulating member; In a first direction, the main body portion has two opposite first surfaces, the second insulating portion is connected to one of the first surfaces, and the first direction is perpendicular to the thickness direction of the first wall portion.

10. The battery cell of claim 9, wherein, The housing comprises a second wall portion connected to the first wall portion, the second wall portion being a wall portion having a largest outer surface area in the housing; In the first direction, the second insulating portion is at least partially located between the main body portion and the second wall portion.

11. The battery cell of claim 9, wherein the cathode comprises a lithium metal oxide. Each of the electrode assemblies is provided with at least one second insulating member, the second insulating member comprising two second insulating portions, the first insulating portion connecting the two second insulating portions, and the two second insulating portions being connected to the two first surfaces of the main body portion, respectively.

12. The battery cell of claim 11, wherein, The battery cell comprises a plurality of electrode assemblies stacked along the first direction, and in two adjacent second insulating members along the first direction, one second insulating portion of one second insulating member is connected with one second insulating portion of another second insulating member.

13. The battery cell according to claim 9, characterized in that, The battery cell comprises a plurality of electrode assemblies stacked along the first direction, and two electrode assemblies at both ends of the plurality of electrode assemblies along the first direction are respectively a first electrode assembly and a second electrode assembly. The second insulating member comprises two second insulating portions, one second insulating portion is connected to a first surface of the first electrode assembly away from the second electrode assembly, and the other second insulating portion is connected to a first surface of the second electrode assembly away from the first electrode assembly.

14. The battery cell according to claim 9, characterized in that, The electrode assembly comprises a positive electrode sheet, a separator and a negative electrode sheet, and the positive electrode sheet, the separator and the negative electrode sheet are wound or stacked. The first surface is a surface of the separator.

15. The battery cell of claim 1, wherein, The second insulating member has a flat plate structure.

16. The battery cell of claim 1, wherein, Each of the electrode assemblies is provided with at least one second insulating member.

17. The battery cell of claim 1, wherein, Each of the second insulating members is located between the main body portion of the plurality of electrode assemblies and the first insulating member.

18. The battery cell of claim 1, wherein, Along the thickness direction of the first wall portion, the main body portion has a first end facing the first wall portion. The electrode assembly comprises two tabs, the polarities of the two tabs are opposite, and the two tabs are both arranged at the first end. The first insulating member is at least partially arranged between the first end and the first wall portion, and the second insulating member is at least partially arranged between the first end and the first wall portion.

19. The battery cell of claim 18, wherein the cathode comprises a lithium metal oxide. The two tabs are arranged at the first end along a second direction. Along the second direction, one of the tabs is provided with the second insulating member on a side away from the other tab.

20. The battery cell of any one of claims 1-19, wherein, The shell comprises a shell body and an end cover, the shell body has an opening, and the end cover closes the opening, the end cover being the first wall portion. The first insulating member is a lower plastic arranged on a side of the end cover facing the electrode assembly.

21. The battery cell of any one of claims 1-19, wherein, The second insulating member is an insulating film.

22. The battery cell of claim 21, wherein the cathode comprises a lithium metal oxide. The thickness of the insulating film is H, and 0.01mm≤H≤0.5mm is satisfied.

23. The battery cell of claim 22, wherein the cathode comprises a lithium metal oxide. 0.05mm≤H≤0.2mm.

24. The battery cell of any one of claims 1-19, wherein, The material damage temperature of the second insulating member is greater than or equal to 150℃.

25. The battery cell of claim 24, wherein the cathode comprises a lithium metal oxide. The material damage temperature of the second insulating member is greater than or equal to 250℃.

26. The battery cell of any one of claims 1-19, wherein, The material of the second insulating member comprises one of polyethylene terephthalate, polyphthalamide, polyphenylene sulfide and polyimide.

27. A battery device, characterized by The battery cell according to any one of claims 1-26.

28. An electrical device, comprising: The battery cell according to any one of claims 1-26 is used to provide electric energy for the electric device.

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