Battery monomer, battery and electric device

Abstract

The embodiment of the invention provides a battery monomer, a battery and an electric device. The battery cell comprises: a housing having a first wall provided with a pressure relief mechanism; the electrode assembly is accommodated in the shell; the supporting structure is arranged between the shell and the electrode assembly, and the supporting structure is used for forming an exhaust channel communicated with a pressure relief mechanism between the first wall and the electrode assembly. According to the battery monomer, the battery and the power utilization device provided by the embodiment of the invention, the possibility of non-directional pressure relief of the battery monomer can be reduced.

Description

Technical Field

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

[0002] In the related art, when a battery cell experiences thermal runaway, the electrode assembly runs the risk of moving toward the first wall of the outer shell on which a pressure relief mechanism is provided, causing the electrode assembly to be pressed against the first wall, thereby blocking the directional pressure relief channel between the first wall and the electrode assembly, causing non-directional pressure relief in the battery cell. Summary of the invention

[0003] In view of this, the embodiments of the present application provide a battery cell, a battery, and an electrical device, which can reduce the probability of non-directional pressure release in the battery cell.

[0004] In a first aspect, a battery cell is provided, comprising: a shell having a first wall, the first wall being provided with a pressure relief mechanism; an electrode assembly accommodated in the shell; and a support structure arranged between the shell and the electrode assembly, the support structure being used to form an exhaust channel between the first wall and the electrode assembly that is connected to the pressure relief mechanism.

[0005] In this embodiment, the support structure is used to form an exhaust channel connected to the pressure relief mechanism between the first wall and the electrode assembly, so that in the event of thermal runaway of the battery cell, the exhaust channel can guide the thermal runaway gas to the pressure relief mechanism, and then the thermal runaway gas can be discharged from the pressure relief mechanism to the outside of the battery cell in time, thereby reducing the possibility of non-directional pressure relief of the battery cell.

[0006] In a possible implementation, the support structure is used to support the electrode assembly.

[0007] In this embodiment, the support structure is used to support the electrode assembly, which is beneficial for forming an exhaust channel connected to the pressure relief mechanism between the first wall and the electrode assembly when thermal runaway occurs in the battery cell, thereby improving the problem of non-directional pressure relief in the battery cell.

[0008] In a possible implementation, the melting point of the support structure is greater than 100°C.

[0009] In this embodiment, a support structure with a melting point greater than 100°C is used, which is beneficial for preventing the battery cell from melting easily when thermal runaway occurs. As a result, an exhaust channel connected to the pressure relief mechanism can be formed between the first wall and the electrode assembly, so that the thermal runaway gas can be discharged to the outside of the battery cell through the pressure relief mechanism in a timely manner, thereby improving the problem of non-directional pressure relief of the battery cell.

[0010] In a possible implementation manner, the support structure includes a first support member disposed between the first wall and the electrode assembly.

[0011] In this embodiment, by arranging the first support member between the first wall and the electrode assembly, the electrode assembly can be directly limited. When thermal runaway occurs in the battery cell, the electrode assembly can be prevented from moving toward the first wall, so that the thermal runaway gas can reach the pressure relief mechanism through the exhaust channel formed between the first wall and the electrode assembly, and then can be discharged from the pressure relief mechanism to the battery cell in time, reducing the possibility of non-directional pressure relief in the battery cell.

[0012] In a possible implementation manner, the first support member is fixedly connected to the first wall.

[0013] In this embodiment, by fixedly connecting the first support member to the first wall so as to dispose the first support member between the first wall and the electrode assembly, the movement of the first support member in the battery cell can be reduced, thereby reducing the probability of the first support member blocking the pressure relief mechanism.

[0014] In a possible implementation manner, the first support member and the first wall are formed integrally.

[0015] In this embodiment, the first support member and the first wall are integrally formed, which can improve the bonding strength between the first wall and the first support member, reduce the movement of the first support member in the battery cell, and reduce the probability of the first support member blocking the pressure relief mechanism.

[0016] In a possible implementation, the battery cell further includes: a first insulating member disposed between the electrode assembly and the first wall; wherein the first insulating member is provided with an escape cavity, and the escape cavity is used to accommodate the first support member.

[0017] In this embodiment, by providing an avoidance cavity on the first insulating member to accommodate the first support member, the insulation between the first wall and the electrode assembly does not need to be affected and no additional space of the battery cell needs to be occupied in the thickness direction of the first wall, thereby improving the energy density of the battery cell.

[0018] In a possible implementation, the battery cell further includes a first insulating member, the first insulating member is used to insulate the first wall and the electrode assembly, and the melting point of the first support is higher than the melting point of the first insulating member.

[0019] In this embodiment, by setting the melting point of the first support member to be higher than the melting point of the first insulating member, the first support member is not easily melted in the later stage of thermal runaway, and can provide an exhaust channel for the thermal runaway gas to reach the pressure relief mechanism, thereby reducing the probability of non-directional pressure relief of the battery cell.

[0020] In a possible implementation, in the thickness direction of the first wall, a projection of the first support member on the first wall is disposed at an end region of the first wall along a first direction, and the first direction is perpendicular to the thickness direction of the first wall.

[0021] In this embodiment, in the thickness direction of the first wall, the projection of the first support member on the first wall is arranged in the end area of ​​the first wall in the first direction, which can minimize the possibility of the first wall at the end in the first direction abutting against the electrode assembly, so that the thermal runaway gas in the battery cell can reach the pressure relief mechanism, reducing the possibility of non-directional pressure relief in the battery cell.

[0022] In a possible implementation, in a first direction, there is a gap between the electrode assembly and the housing, and the first support member is provided with a first cavity penetrating along the first direction, and the first cavity is used to connect the gap and the pressure relief mechanism.

[0023] In this embodiment, the first support member is provided with a first cavity extending along a first direction, which is used to connect the gap and the pressure relief mechanism so as to guide the thermal runaway gas accumulated in the gap to the pressure relief mechanism, thereby reducing the possibility that the thermal runaway gas accumulated in the gap will not have time to be exhausted and cause the shell to be ruptured.

[0024] In a possible implementation manner, the first support member is provided with at least one first through hole penetrating along the first direction, and the first cavity includes the at least one first through hole.

[0025] In this embodiment, by providing at least one first through hole extending through the first direction in the first support member to form a first cavity, on the one hand, the possibility of the outer shell being ruptured due to the thermal runaway gas accumulated in the gap not being able to be exhausted in time can be reduced; on the other hand, the weight of the battery cell can be reduced and the energy density of the battery cell can be improved.

[0026] In one possible implementation, the first support member includes a plurality of first support blocks spaced apart in a second direction, the first cavity includes a gap between every two adjacent first support blocks among the plurality of first support blocks, the second direction is perpendicular to the thickness direction of the first wall, and the second direction is perpendicular to the first direction.

[0027] In this embodiment, a plurality of first support blocks are spaced apart in the second direction to form a first cavity. On the one hand, this can reduce the possibility that the thermal runaway gas accumulated in the gap will not have time to be exhausted and the outer shell will be broken; on the other hand, it can also reduce the weight of the battery cell and improve the energy density of the battery cell.

[0028] In a possible implementation, in the thickness direction of the first wall, a dimension h of the first support member and a dimension c of the battery cell satisfy the following relationship: 0.003≤h / c≤0.13.

[0029] In this embodiment, if h / c is less than 0.003, it is very easy to be blocked by particulate matter or pole pieces generated by the loss of control inside the battery cell, thereby failing to achieve the purpose of forming an exhaust channel; and when h / c is greater than 0.13, the energy density of the battery cell will be seriously sacrificed; setting h / c between 0.003 and 0.13 can achieve the purpose of balancing the energy density of the battery cell and forming an exhaust channel between the first wall and the electrode assembly.

[0030] In a possible implementation, at least one first support member is provided between the first wall and the electrode assembly, and in the thickness direction of the first wall, the total projected area S1 of the at least one first support member on the first wall and the area S of the first wall satisfy: 0.012≤S1 / S≤0.26.

[0031] In this embodiment, when S1 / S is less than 0.012, when thermal runaway occurs in the battery cell, the contact area between the first support member and the first wall is too small, which cannot provide sufficient mechanical support for the electrode assembly, which may cause the internal electrode assembly to shake or overlap with the first wall, and even further deteriorate the exhaust path; and when S1 / S is greater than 0.26, on the one hand, the weight of the battery cell will increase, sacrificing energy density, and on the other hand, the first support member will further reduce the internal free space of the battery cell, which is not conducive to directional pressure relief. Setting S1 / S between 0.012 and 0.26 can achieve the purpose of balancing the energy density of the battery cell and forming an exhaust channel between the first wall and the electrode assembly.

[0032] In a possible implementation manner, the housing further includes a second wall, the second wall intersects with the first wall, and the supporting structure includes a second supporting member fixedly connected to the second wall.

[0033] In this embodiment, a second support member is fixedly provided on the second wall of the outer shell intersecting with the first wall to support the electrode assembly. This helps prevent the end of the electrode assembly from moving toward the first wall when thermal runaway occurs in the battery cell, thereby increasing the probability of forming an exhaust channel between the first wall and the electrode assembly when thermal runaway occurs in the battery cell.

[0034] In a possible implementation, the second wall forms a receiving space having an opening, the first wall covers the opening to arrange the electrode assembly in the receiving space, and the second support member is arranged at the opening.

[0035] In this embodiment, by arranging the second support member at the opening of the accommodating space formed by the second wall, the possibility of blocking the end of the electrode assembly from moving toward the first wall can be increased, thereby increasing the probability of forming an exhaust channel between the first wall and the electrode assembly when thermal runaway occurs in the battery cell.

[0036] In a possible implementation, the second support member is provided with a second cavity penetrating along the thickness direction of the first wall, and the second cavity is used to guide the thermal runaway gas accumulated between the second wall and the electrode assembly to the exhaust channel.

[0037] In this embodiment, by providing the second support member with a second cavity that passes through the first wall in the thickness direction, the electrode assembly can be supported by the second support member to reduce the possibility of the end of the electrode assembly moving toward the first wall, and the thermal runaway gas accumulated between the second wall and the electrode assembly 32 can be guided to the exhaust channel through the second cavity, thereby reducing the possibility of non-directional pressure release of the battery cell.

[0038] In a possible implementation, the second support member includes a plurality of second support blocks spaced apart along the circumference of the opening, and the second cavity includes a space between every two second support blocks in the plurality of second support blocks.

[0039] In this embodiment, a plurality of second support blocks are arranged at intervals along the circumference of the opening to form a second cavity, which can reduce the possibility that the thermal runaway gas accumulated between the second wall and the electrode assembly cannot be exhausted in time and thus causes the shell to be broken.

[0040] In one possible implementation, in the thickness direction of the first wall, the surface of the second support member away from the first wall is closer to the first wall than the surface of the electrode assembly close to the first wall; in the thickness direction of the first wall, the projection of the second support member on the first wall and the projection of the electrode assembly on the first wall have an intersection.

[0041] In this embodiment, in the thickness direction of the first wall, the projection of the second support member on the first wall and the projection of the electrode assembly on the first wall have an intersection, and the second support member is closer to the first wall than the electrode assembly, so that when thermal runaway occurs in the battery cell, the second support member can block the electrode assembly from approaching the first wall, thereby forming an exhaust channel between the first wall and the electrode assembly, reducing the possibility of non-directional pressure release in the battery cell.

[0042] In a possible implementation, the battery cell further includes: an insulating assembly, disposed between the outer shell and the electrode assembly, for insulating the outer shell and the electrode assembly; the support structure includes a third support member, the third support member is fixedly connected to the insulating assembly, and the third support member is disposed between the outer shell and the insulating assembly.

[0043] In this embodiment, a third support member is provided between the outer shell and the insulating assembly provided between the outer shell and the electrode assembly, and the third support member is fixedly connected to the insulating assembly to support the electrode assembly. This helps to reduce the possibility of the electrode assembly moving toward the first wall when thermal runaway occurs in the battery cell, thereby increasing the probability of forming an exhaust channel between the first wall and the electrode assembly.

[0044] In a possible implementation, the insulating assembly includes a first insulating component, the first insulating component is disposed between the first wall and the electrode assembly, and the third support is fixedly connected to the first insulating component.

[0045] In this embodiment, by disposing a first insulating member between the first wall and the electrode assembly and fixing the third support member to the first insulating member, the possibility of the electrode assembly moving toward the first wall can be reduced when thermal runaway occurs in the battery cell, thereby increasing the probability of forming an exhaust channel between the first wall and the electrode assembly.

[0046] In a possible implementation, the insulating assembly includes a second insulating component, the second insulating component is coated on the outer surface of the electrode assembly, and the third support member is fixedly connected to the second insulating component.

[0047] In this embodiment, by fixing the third support member to the second insulating member covering the outer surface of the electrode assembly to support the electrode assembly, the possibility of the electrode assembly moving toward the first wall is reduced when thermal runaway occurs in the battery cell, thereby increasing the probability of forming an exhaust channel between the first wall and the electrode assembly.

[0048] In a possible implementation, the third support member is fixedly connected to the insulating assembly by snapping.

[0049] In this embodiment, the third support member and the insulating assembly are fixedly connected by snapping, which can improve the bonding strength between the third support member and the insulating assembly and reduce the probability of the third support member moving inside the battery cell to block the exhaust channel A.

[0050] In a possible implementation manner, the third support member is fixedly connected to the insulating assembly by bonding.

[0051] In this embodiment, the third support member and the insulating assembly can be fixedly connected by bonding, which can improve the bonding strength between the third support member and the insulating assembly and reduce the probability of the third support member moving inside the battery cell to block the exhaust channel.

[0052] In a possible implementation, the third support member has a second through hole, and the second through hole is used to release the thermal runaway gas generated by the electrode assembly to between the insulation assembly and the shell.

[0053] In this embodiment, by setting a second through hole in the third support member, the thermal runaway gas generated by the electrode assembly can be released between the insulating assembly and the outer shell in a timely manner, so that the thermal runaway gas can be further guided to the exhaust channel and discharged through the pressure relief mechanism.

[0054] In a possible implementation manner, the third support member is provided with a groove opening toward the housing.

[0055] In this embodiment, by providing a groove with an opening toward the shell on the third support member, on the one hand, the accommodation space for the thermal runaway gas can be increased, and on the other hand, the weight of the battery cell can be reduced and the energy density of the battery cell can be improved.

[0056] In one possible implementation, the battery cell also includes: a support plate, arranged between the electrode assembly and the shell, and located below the electrode assembly along the direction of gravity; the support structure includes a fourth support member, arranged below the electrode assembly along the direction of gravity, and the melting point of the fourth support member is higher than the melting point of the support plate.

[0057] In this embodiment, a fourth support member is provided on a side where a support plate is provided to support the electrode assembly, and the melting point of the fourth support member is higher than the melting point of the support plate. This is beneficial in that in the event of thermal runaway of the battery cell, even if the support plate is melted, the fourth support member is not easily melted, and can still play a role in supporting the electrode assembly, and a space is formed to accommodate the thermal runaway gas, thereby reducing the possibility of non-directional pressure release of the battery cell.

[0058] In a possible implementation manner, the fourth support member is fixedly connected to the support plate.

[0059] In this embodiment, by fixedly connecting the fourth support member to the support plate, a space for accommodating thermal runaway gas is formed between the electrode assembly and the support plate, thereby reducing the possibility of non-directional pressure release of the battery cell.

[0060] In a possible implementation manner, the first wall is an end cover.

[0061] In this embodiment, the first support member is fixed together with the end cover. Compared with fixing the first support member to other walls of the shell, the first support member and the end cover can be fixed together externally, or the first support member can be directly formed when preparing the end cover, without extending the first support member into the shell for fixing, thereby improving the preparation efficiency of the battery cell.

[0062] In a possible implementation, the battery cell further includes: an electrode terminal disposed on the first wall; and the electrode terminal is electrically connected to the electrode assembly.

[0063] In this embodiment, by providing electrical connection between the electrode terminal of the first wall and the electrode assembly, electrical connection with other battery cells can be achieved, thereby achieving the purpose of expanding the battery capacity.

[0064] In a second aspect, a battery is provided, comprising the battery cell in the first aspect and any possible implementation manner of the first aspect.

[0065] In a third aspect, an electrical device is provided, comprising the battery in the second aspect, wherein the battery is used to provide electrical energy to the electrical device. BRIEF DESCRIPTION OF THE DRAWINGS

[0066] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings required for use in the embodiments of the present application will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on the drawings without paying creative work.

[0067] Figure 1 It is a structural schematic diagram of a vehicle disclosed in one embodiment of the present application.

[0068] Figure 2 It is a schematic diagram of the structure of a battery disclosed in one embodiment of the present application.

[0069] Figure 3 It is a schematic diagram of an exploded view of a battery cell disclosed in an embodiment of the present application.

[0070] Figure 4 It is a planar cross-sectional view of a battery cell disclosed in one embodiment of the present application.

[0071] Figure 5 It is a schematic diagram of an exploded view of a battery cell disclosed in another embodiment of the present application.

[0072] Figure 6 Shows Figure 5 Partial cross-sectional view of the battery cell along the YZ plane.

[0073] Figure 7 A schematic diagram of the connection between the first wall and the first support member disclosed in an embodiment of the present application is shown.

[0074] Figure 8 A schematic diagram of the connection between the first insulating component and the first supporting member disclosed in an embodiment of the present application is shown.

[0075] Fig. 9 Another planar cross-sectional view of a battery cell disclosed in an embodiment of the present application is shown.

[0076] Fig.10A top view of a first wall disclosed in an embodiment of the present application is shown.

[0077] Fig.11 A schematic diagram of an exploded view of another battery cell disclosed in an embodiment of the present application is shown.

[0078] Fig.12 Shows Fig. 9 Cross-sectional view of the shell along the XZ plane.

[0079] Fig.13 Shows Fig. 9 Cross-sectional view of the battery cell along the YZ plane.

[0080] Fig.14 A schematic diagram of an exploded view of another battery cell disclosed in an embodiment of the present application is shown.

[0081] Fig.15 A schematic diagram of an exploded view of another battery cell disclosed in an embodiment of the present application is shown.

[0082] Fig.16 A schematic diagram of a first connection between a third support member and a second insulating member disclosed in an embodiment of the present application is shown.

[0083] Fig.17 A second connection schematic diagram between the third support member and the second insulating member disclosed in an embodiment of the present application is shown.

[0084] Fig.18 A structural schematic diagram of a second insulating component disclosed in an embodiment of the present application is shown.

[0085] Fig.19 Another structural schematic diagram of the second insulating component disclosed in an embodiment of the present application is shown.

[0086] Fig. 20 Another planar cross-sectional view of a battery cell disclosed in an embodiment of the present application is shown. DETAILED DESCRIPTION

[0087] In order to make the purpose, technical solution and advantages of the embodiments of the present application clearer, the technical solution in the embodiments of the present application will be clearly described below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of this application.

[0088] Unless otherwise defined, all technical and scientific terms used in this application have the same meaning as those commonly understood by technicians in the technical field to which this application belongs; the terms used in the specification of this application are only for the purpose of describing specific embodiments and are not intended to limit this application; the terms "including" and "having" and any variations thereof in the specification and claims of this application and the above-mentioned drawings are intended to cover non-exclusive inclusions. The terms "first", "second", etc. in the specification and claims of this application or the above-mentioned drawings are used to distinguish different objects, rather than to describe a specific order or a primary and secondary relationship.

[0089] The directional words appearing in the following description are all directions shown in the figures, and do not limit the specific structure of this application. In the description of this application, it should also be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection; it can be directly connected or indirectly connected through an intermediate medium. For ordinary technicians in this field, the specific meanings of the above terms in this application can be understood according to the specific circumstances.

[0090] Reference to "embodiments" in this application means that a particular feature, structure, or characteristic described in conjunction with the embodiments may be included in at least one embodiment of the present application. The appearance of the phrase in various locations in the specification does not necessarily refer to the same embodiment, nor is it an independent or alternative embodiment that is mutually exclusive with other embodiments. It is explicitly and implicitly understood by those skilled in the art that the embodiments described in this application may be combined with other embodiments.

[0091] The term "and / or" in this application is only a description of the association relationship of associated objects, indicating that there can be three relationships. For example, A and / or B can represent: A exists alone, A and B exist at the same time, and B exists alone. In addition, the character " / " in this application generally indicates that the associated objects before and after are in an "or" relationship.

[0092] The term "multiple" as used in this application refers to more than two (including two). Similarly, "multiple groups" refers to more than two groups (including two groups), and "multiple sheets" refers to more than two sheets (including two sheets).

[0093] In the embodiment of the present application, the battery cell may be a secondary battery. A secondary battery refers to a battery cell that can be continuously used by activating active materials by charging after the battery cell is discharged.

[0094] The battery cell can be a lithium ion battery, a sodium ion battery, a sodium lithium ion battery, a lithium metal battery, a sodium metal battery, a lithium sulfur battery, a magnesium ion battery, a nickel hydrogen battery, a nickel cadmium battery, a lead storage battery, etc., which is not limited in the embodiments of the present application.

[0095] A battery cell generally includes an electrode assembly. The electrode assembly includes a positive electrode, a negative electrode, and a separator. During the charge and discharge process of the battery cell, active ions (such as lithium ions) are embedded and removed between the positive electrode and the negative electrode. The separator is set between the positive electrode and the negative electrode to prevent the positive and negative electrodes from short-circuiting, while allowing active ions to pass through.

[0096] In some embodiments, the positive electrode may be a positive electrode sheet, and the positive electrode sheet may include a positive electrode current collector and a positive electrode active material disposed on at least one surface of the positive electrode current collector.

[0097] As an example, the positive electrode current collector has two surfaces facing each other in its thickness direction, and the positive electrode active material is disposed on either or both of the two facing surfaces of the positive electrode current collector.

[0098] As an example, the positive electrode current collector may be a metal foil or a composite current collector. For example, as the metal foil, aluminum or stainless steel, stainless steel, copper, aluminum, nickel, carbon electrode, carbon, nickel or titanium, etc., treated with silver surface, may be used. The composite current collector may include a polymer material base and a metal layer. The composite current collector may be formed by forming a metal material (aluminum, aluminum alloy, nickel, nickel alloy, titanium, titanium alloy, silver and silver alloy, etc.) on a polymer material substrate (such as a substrate of polypropylene, polyethylene terephthalate, polybutylene terephthalate, polystyrene, polyethylene, etc.).

[0099] As an example, the positive electrode active material may include at least one of the following materials: lithium-containing phosphates, lithium transition metal oxides, and their respective modified compounds. However, the present application is not limited to these materials, and other traditional materials that can be used as positive electrode active materials for batteries may also be used. These positive electrode active materials may be used alone or in combination of two or more. Among them, examples of lithium-containing phosphates may include, but are not limited to, at least one of lithium iron phosphate (such as LiFePO4 (also referred to as LFP)), a composite material of lithium iron phosphate and carbon, lithium manganese phosphate (such as LiMnPO4), a composite material of lithium manganese phosphate and carbon, lithium iron manganese phosphate, and a composite material of lithium iron manganese phosphate and carbon.

[0100] In some embodiments, the negative electrode may be a negative electrode sheet, and the negative electrode sheet may include a negative electrode current collector.

[0101] As an example, the negative electrode current collector may be a metal foil or a composite current collector. For example, as the metal foil, aluminum or stainless steel treated with silver, stainless steel, copper, aluminum, nickel, carbon electrode, carbon, nickel or titanium, etc. may be used. The composite current collector may include a polymer material base and a metal layer. The composite current collector may be formed by forming a metal material (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.).

[0102] 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.

[0103] As an example, the negative electrode current collector has two surfaces facing each other in its thickness direction, and the negative electrode active material is disposed on either or both of the two facing surfaces of the negative electrode current collector.

[0104] As an example, the negative electrode active material may adopt the negative electrode active material for battery cells known in the art. As an example, the negative electrode active material may include at least one of the following materials: artificial graphite, natural graphite, soft carbon, hard carbon, silicon-based materials, tin-based materials, lithium titanate, etc.

[0105] In some embodiments, the negative electrode may be a foam metal. The foam metal may be foam nickel, foam copper, foam aluminum, foam alloy, or foam carbon, etc. When the foam metal is used as the negative electrode plate, the surface of the foam metal may not be provided with a negative electrode active material, but of course, a negative electrode active material may also be provided.

[0106] As an example, a lithium source material, potassium metal or sodium metal may be filled or / and deposited in the negative electrode current collector, and the lithium source material is lithium metal and / or lithium-rich material.

[0107] In some embodiments, the material of the positive electrode current collector may be aluminum, and the material of the negative electrode current collector may be copper.

[0108] In some embodiments, the electrode assembly further includes a separator disposed between the positive electrode and the negative electrode.

[0109] In some embodiments, the separator is a separator. The present application has no particular limitation on the type of separator, and any known separator with a porous structure having good chemical stability and mechanical stability can be selected.

[0110] As an example, the main material of the isolation membrane can be selected from at least one of glass fiber, non-woven fabric, polyethylene, polypropylene, polyvinylidene fluoride, and ceramics.

[0111] In some embodiments, the separator is a solid electrolyte, which is disposed between the positive electrode and the negative electrode and serves to transmit ions and isolate the positive and negative electrodes.

[0112] In some embodiments, the battery cell further includes an electrolyte, which acts as a conductor of ions between the positive and negative electrodes. The present application has no specific restrictions on the type of electrolyte, which can be selected according to needs. The electrolyte can be liquid, gel or solid.

[0113] In some embodiments, the electrode assembly is a wound structure, wherein the positive electrode sheet and the negative electrode sheet are wound into a wound structure.

[0114] In some embodiments, the electrode assembly is a laminate structure.

[0115] As an example, a plurality of positive electrode sheets and a plurality of negative electrode sheets may be provided respectively, and the plurality of positive electrode sheets and the plurality of negative electrode sheets may be alternately stacked.

[0116] As an example, a plurality of positive electrode sheets may be provided, and the negative electrode sheet is folded to form a plurality of stacked folded segments, with a positive electrode sheet sandwiched between adjacent folded segments.

[0117] As an example, both the positive electrode sheet and the negative electrode sheet are folded to form a plurality of stacked folded sections.

[0118] As an example, a plurality of separators may be provided, each of which is provided between any adjacent positive electrode sheets or negative electrode sheets.

[0119] As an example, the separator may be disposed continuously, and may be disposed between any adjacent positive electrode sheets or negative electrode sheets by folding or winding.

[0120] In some embodiments, the shape of the electrode assembly can be cylindrical, flat, or polygonal.

[0121] In some embodiments, the electrode assembly is provided with tabs, which can lead current out of the electrode assembly. The tabs include a positive tab and a negative tab.

[0122] In some embodiments, the battery cell may include a housing. The housing is used to encapsulate components such as the electrode assembly and the electrolyte. The housing may be a steel housing, an aluminum housing, a plastic housing (such as polypropylene), a composite metal housing (such as a copper-aluminum composite housing), or an aluminum-plastic film. The housing includes a shell and an end cap.

[0123] As an example, the battery cell can be a cylindrical battery cell, a prismatic battery cell, a soft-pack battery cell or a battery cell of other shapes. The prismatic battery cell includes a square shell battery cell, a blade-shaped battery cell, a polygonal battery, such as a hexagonal battery, etc. There is no special limitation in this application.

[0124] The battery mentioned in the embodiments of the present application may include one or more battery cells to provide a single physical module with higher voltage and capacity. When there are multiple battery cells, the multiple battery cells are connected in series, in parallel or in mixed connection through a busbar component.

[0125] In some embodiments, the battery may be a battery module. When there are multiple battery cells, the multiple battery cells are arranged and fixed to form a battery module.

[0126] In some embodiments, the battery may be a battery pack, which includes a case and battery cells, wherein the battery cells or battery modules are accommodated in the case.

[0127] In some embodiments, the box body can be used as a part of the chassis structure of the vehicle. For example, part of the box body can become at least a part of the floor of the vehicle, or part of the box body can become at least a part of the cross beam and longitudinal beam of the vehicle.

[0128] At present, when a battery cell experiences internal or external short circuit due to mechanical external force or other reasons, it may lead to thermal runaway of the battery cell. A large amount of thermal runaway gas will be generated inside instantly. The generated gas needs to pass through the electrode assembly and its mechanical parts inside the battery cell to reach the pressure relief mechanism, and open the pressure relief mechanism through the internal and external pressure difference, thereby achieving directional pressure relief.

[0129] However, as the energy density of battery cells continues to increase, the thermal runaway rate of battery cells continues to increase, and the gas production rate and gas production volume increase significantly. Under the current battery cell design, non-directional pressure relief may occur during thermal runaway. For example, the exhaust passage in the battery cell that reaches the pressure relief mechanism is blocked, causing damage to the shell and gas pressure relief from the damaged part. This phenomenon will cause secondary disasters of verification at the system level, such as impacting adjacent battery cells to cause heat diffusion, and impacting high-voltage wiring harnesses to cause high-voltage ignition.

[0130] In view of this, an embodiment of the present application provides a battery cell, in which a support structure is arranged between the outer shell and the electrode assembly, and the support structure is used to support the electrode assembly, so as to form an exhaust channel between the first wall of the outer shell provided with a pressure relief mechanism and the electrode assembly to guide the thermal runaway gas to the pressure relief mechanism, so that the thermal runaway gas can be discharged to the outside of the battery cell through the pressure relief mechanism in time, thereby reducing the possibility of non-directional pressure relief in the battery cell.

[0131] The technical solutions described in the embodiments of the present application are applicable to various devices that use batteries, such as mobile phones, portable devices, laptops, electric vehicles, electric toys, electric tools, electric vehicles, ships and spacecraft, for example, spacecraft include airplanes, rockets, space shuttles and spacecraft, etc.

[0132] It should be understood that the technical solutions described in the embodiments of the present application are not limited to the devices described above, but can also be applied to all devices using batteries. However, for the sake of simplicity, the following embodiments are described using electric vehicles as examples.

[0133] For example, Figure 1 As shown, it is a structural schematic diagram of a vehicle 1 according to an embodiment of the present application. The vehicle 1 may be a fuel vehicle, a gas vehicle or a new energy vehicle. The new energy vehicle may be a pure electric vehicle, a hybrid vehicle or an extended-range vehicle, etc. A motor 80, a controller 60 and a battery 100 may be arranged inside the vehicle 1. The controller 60 is used to control the battery 100 to supply power to the motor 80. For example, a battery 100 may be arranged at the bottom, front or rear of the vehicle 1. The battery 100 may be used to supply power to the vehicle 1. For example, the battery 100 may be used as an operating power source for the vehicle 1, for the circuit system of the vehicle 1, for example, for the working power requirements during the start-up, navigation and operation of the vehicle 1. In another embodiment of the present application, the battery 100 may not only be used as an operating power source for the vehicle 1, but also as a driving power source for the vehicle 1, replacing or partially replacing fuel or natural gas to provide driving power for the vehicle 1.

[0134] For example, Figure 2 , which is a schematic diagram of the structure of a battery 100 according to an embodiment of the present application. The battery 100 may include a plurality of battery cells 20. In addition to the battery cells 20, the battery 100 may also include a box body, the interior of the box body is a hollow structure, and the plurality of battery cells 20 may be accommodated in the box body. Figure 2 As shown, the box body may include two parts, which are respectively referred to as a first box body part 111 and a second box body part 112, and the first box body part 111 and the second box body part 112 are buckled together. The shapes of the first box body part 111 and the second box body part 112 may be determined according to the shapes of the combination of multiple battery cells 20, and at least one of the first box body part 111 and the second box body part 112 has an opening. For example, Figure 2 As shown, only one of the first box body 111 and the second box body 112 is a hollow cuboid with an opening, and the other is in a plate shape to cover the opening. Here, taking the second box body 112 as a hollow cuboid with only one face as an opening face, and the first box body 111 as a plate-shaped example, the first box body 111 covers the opening of the second box body 112 to form a box body 11 with a closed chamber, which can be used to accommodate multiple battery cells 20. After the multiple battery cells 20 are connected in parallel, in series or in mixed series, they are placed in the box body formed by the first box body 111 and the second box body 112 being buckled together.

[0135] For example, different from Figure 2As shown, the first box body 111 and the second box body 112 can both be hollow cuboids and each have only one open face, the opening of the first box body 111 and the opening of the second box body 112 are arranged opposite to each other, and the first box body 111 and the second box body 112 are buckled together to form a box with a closed chamber. A plurality of battery cells 20 are connected in parallel, in series or in a mixed combination and are placed in the box formed by the first box body 111 and the second box body 112 buckled together.

[0136] In some embodiments, the battery 100 may also include other structures, which are not described one by one here. For example, the battery 100 may also include a busbar component (not shown in the figure), which is used to realize the electrical connection between multiple battery cells 20. Specifically, the busbar component can realize the electrical connection between the battery cells 20 by connecting the electrode terminals of the battery cells 20. In some embodiments, the busbar component can be fixed to the electrode terminals of the battery cells 20 by welding. The electrical energy of multiple battery cells 20 can be further led out through the box through the conductive mechanism. In some embodiments, the conductive mechanism may also belong to the busbar component.

[0137] In order to meet different power requirements, the number of battery cells 20 can be multiple, and multiple battery cells can be connected in series, in parallel, or in hybrid connection, where hybrid connection refers to a mixture of series and parallel connection. Battery 100 can also be called a battery pack. In some embodiments, multiple battery cells can be connected in series, in parallel, or in hybrid connection to form a battery module, and multiple battery modules can be connected in series, in parallel, or in hybrid connection to form battery 100. In other words, multiple battery cells can directly form battery 100, or they can first form battery modules, and then the battery modules can form battery 100.

[0138] Figure 3 A schematic exploded view of a battery cell 20 according to an embodiment of the present application is shown.

[0139] like Figure 3As shown, the battery cell 20 includes one or more electrode assemblies 22, a shell 211 and an end cap 212, wherein the wall of the shell 211 and the end cap 212 are both referred to as the wall of the battery cell 20. The shell 211 is determined according to the shape of the one or more electrode assemblies 22 after being combined. For example, the shell 211 may be a hollow cuboid or a cube or a cylinder, and one of the faces of the shell 211 has an opening so that one or more electrode assemblies 22 can be placed in the shell 211. For example, when the shell 211 is a hollow cuboid or a cube, one of the planes of the shell 211 is an open face, that is, the plane does not have a wall body so that the inside and outside of the shell 211 are connected. When the shell 211 may be a hollow cylinder, the end face of the shell 211 is an open face, that is, the end face does not have a wall body so that the inside and outside of the shell 211 are connected. The end cap 212 covers the opening and is connected to the shell 211 to form a closed cavity for placing the electrode assembly 22. The housing 211 is filled with an electrolyte, such as an electrolyte solution.

[0140] The battery cell 20 also includes two electrode terminals 214. The end cap 212 is generally in the shape of a flat plate, and the two electrode terminals 214 are fixed on the flat surface of the end cap 212, and the two electrode terminals 214 are respectively a positive electrode terminal 214a and a negative electrode terminal 214b. Each electrode terminal 214 is provided with a corresponding connection member 23, or it can also be called a current collecting member, which is located between the end cap 212 and the electrode assembly 22, and is used to electrically connect the electrode assembly 22 and the electrode terminal 214.

[0141] like Figure 3 As shown, each electrode assembly 22 has a first pole tab 221a and a second pole tab 222a. The polarities of the first pole tab 221a and the second pole tab 222a are opposite. For example, when the first pole tab 221a is a positive pole tab, the second pole tab 222a is a negative pole tab. The first pole tab 221a of one or more electrode assemblies 22 is connected to an electrode terminal 214 through a connecting member 23, and the second pole tab 222a of one or more electrode assemblies 22 is connected to another electrode terminal 214 through another connecting member 23. For example, the first pole tab 221a is a positive pole tab, the second pole tab 222a is a negative pole tab, the positive electrode terminal 214a is connected to the first pole tab 221a through a connecting member 23, and the negative electrode terminal 214b is connected to the second pole tab 222a through another connecting member 23.

[0142] In the battery cell 20, the electrode assembly 22 can be provided as a single electrode assembly or multiple electrode assemblies according to actual use requirements. Figure 3 As shown, four independent electrode assemblies 22 are disposed in the battery cell 20 .

[0143] As an example, a pressure relief mechanism 213 may be further provided on one wall of the battery cell 20. The pressure relief mechanism 213 is used to be actuated to release the internal pressure or temperature of the battery cell 20 when the internal pressure or temperature reaches a threshold.

[0144] Optionally, the pressure relief mechanism 213 may be disposed on the end cover 212 , or on any wall of the housing 211 .

[0145] Figure 4 A plan cross-sectional view of a battery cell 30 according to an embodiment of the present application is shown.

[0146] like Figure 4 The battery cell 30 includes: a shell 31 having a first wall 311, on which a pressure relief mechanism 312 is arranged; an electrode assembly 32 accommodated in the shell 31; a support structure 33, which is arranged between the shell 31 and the electrode assembly 32, and the support structure 33 is used to form an exhaust channel A between the first wall 311 and the electrode assembly 32 that is connected to the pressure relief mechanism 312.

[0147] It should be explained that the housing 31 may include Figure 3 In the housing 211 and the end cover 212 shown, the first wall 311 can be any wall of the housing 211 or the end cover 212. In other words, the pressure relief mechanism 213 can be disposed on any wall of the battery cell 30.

[0148] The support structure 33 is used to form an exhaust channel A between the first wall 311 and the electrode assembly 32 that is connected to the pressure relief mechanism 312. Specifically, when thermal runaway occurs in the battery cell 30, the existence of the support structure 33 can separate the first wall 311 and the electrode assembly 32, and form an exhaust channel A between the first wall 311 and the electrode assembly 32. The exhaust channel A can guide the thermal runaway gas to the pressure relief mechanism 312, so that the thermal runaway gas is discharged from the pressure relief mechanism 312 to the outside of the battery cell 30.

[0149] In this embodiment, the support structure 33 is used to form an exhaust channel A connected to the pressure relief mechanism 312 between the first wall 311 and the electrode assembly 32, so that when the battery cell 30 has thermal runaway, the exhaust channel A can guide the thermal runaway gas to the pressure relief mechanism 312, and then the thermal runaway gas can be discharged from the pressure relief mechanism 312 to the outside of the battery cell 30 in time, thereby reducing the possibility of non-directional pressure relief of the battery cell 30.

[0150] In some embodiments, the support structure 33 is used to support the electrode assembly 32 .

[0151] In other words, the support structure 33 may restrict the electrode assembly 32 from moving toward the first wall 311 .

[0152] For example, the support structure 33 is used to support the electrode assembly 32 when the battery cell 30 has thermal runaway. For another example, the support structure 33 can support the electrode assembly 32 regardless of whether the battery cell 30 has thermal runaway. The embodiment of the present application is not limited to this.

[0153] In this embodiment, the support structure 33 is used to support the electrode assembly 32, which is beneficial for forming an exhaust channel A connected to the pressure relief mechanism 312 between the first wall 311 and the electrode assembly 32 when thermal runaway occurs in the battery cell 30, thereby improving the problem of non-directional pressure relief of the battery cell 30.

[0154] In some other embodiments, the melting point of the support structure 33 is greater than 100°C.

[0155] In an example, the material of the support structure 33 may be a single material, for example, the material of the support structure 33 is a single material such as aluminum material or copper material. In this case, the support structure 33 has a fixed melting point.

[0156] In another example, the material of the support structure 33 may be a composite material. For example, the support structure 33 may be a mixed material of aluminum material and copper material. In this case, the first support member 331 does not have a fixed melting point, that is, the melting point of the support structure 33 is the melting point range of various materials. For example, the melting point of aluminum material is 660°C, and the melting point of copper is 1083°C, then the melting point range of the support structure 33 is 660°C to 1083°C, and the melting point of the support structure 33 is higher than the melting point of the insulating member 34. It can be understood that the lowest melting point in the melting point range of the support structure 33 is higher than the melting point of the insulating member 34.

[0157] For example, when the positive electrode material of the battery cell is a compound with an olivine structure, the melting point of the support structure 33 can be greater than 150°C, so that the thermal runaway gas can smoothly reach the pressure relief mechanism 312 before the pressure relief mechanism 312 opens the valve. Further optionally, the melting point of the support structure 33 is greater than 500°C, so that the battery cell 30 can still maintain mechanical strength during the thermal runaway process. Among them, the compound with an olivine structure can be selected from lithium iron phosphate, lithium iron manganese phosphate, or a mixture of lithium iron phosphate and lithium iron manganese phosphate.

[0158] For another example, for the positive electrode material of the battery cell containing a layered compound, the melting point of the support structure 33 can be greater than 100°C, so that the thermal runaway gas can smoothly reach the pressure relief mechanism 312 before the pressure relief mechanism 312 opens the valve. Further optionally, the melting point of the support structure 33 is greater than 400°C, so that the battery cell 30 can still maintain mechanical strength during thermal runaway. Among them, the layered compound can be selected from lithium nickel cobalt manganese oxygen ternary layered materials, or a mixture of lithium iron phosphate and lithium nickel cobalt manganese oxygen ternary layered materials, or a mixture of lithium manganese iron and lithium nickel cobalt manganese oxygen ternary layered materials.

[0159] Optionally, the material of the support structure 33 may be a high temperature resistant material. For example, the material of the support structure 33 may include at least one of metal, graphite, polytetrafluoroethylene, mica or ceramic. In some embodiments, the support structure 33 itself may directly adopt a material having insulating properties such as polytetrafluoroethylene, mica or ceramic. In other embodiments, the support structure 33 itself may adopt a metal material, and an insulating layer may be provided on its outer surface.

[0160] In this embodiment, a support structure 33 with a melting point greater than 100°C is used, which is advantageous in that the battery cell 30 is not easily melted when thermal runaway occurs, thereby being able to form an exhaust channel A connected to the pressure relief mechanism 312 between the first wall 311 and the electrode assembly 32, so that the thermal runaway gas can be discharged to the outside of the battery cell 30 through the pressure relief mechanism 312 in a timely manner, thereby improving the problem of non-directional pressure relief of the battery cell 30.

[0161] It should be understood that the embodiment of the present application does not limit the positional relationship between the support structure 33 and the wall of the housing 31. For example, the support structure 33 is set between the first wall 311 and the electrode assembly 32, directly restricting the movement of the electrode assembly 32 toward the first wall 311. For another example, the support structure 33 is set between the side walls intersecting with the first wall 311, and the movement of the electrode assembly 32 toward the first wall 311 is indirectly restricted by the friction between the support structure 33 and the electrode assembly 32. It should also be understood that the embodiment of the present application does not limit the components fixedly connected to the support structure 33. For example, the support structure 33 can be directly fixed on the first wall 311. For another example, the support structure 33 can be fixedly connected to the second wall intersecting with the first wall. For another example, the support structure 33 can also be fixedly connected to the insulating component, and the embodiment of the present application does not make any limitation on this.

[0162] According to the components fixedly connected to the support structure 33, Figures 5 to 7 as well as Fig. 9 and Fig.10 Various schematic diagrams of an embodiment in which the support structure 33 is fixedly connected to the first wall 311 are shown. Figures 11 to 13Various schematic diagrams of an embodiment in which the support structure 33 is fixedly connected to the second wall 313 of the housing 31 are shown. Figure 8 as well as Figures 14 to 19 Various schematic diagrams of an embodiment in which the support structure 33 is fixedly connected to the insulating assembly 40 are shown. Fig. 20 A schematic diagram of an embodiment in which the support structure 33 is fixedly connected to the support plate 50 is shown.

[0163] According to the positional relationship between the support structure 33 and the wall of the housing 31, Figures 5 to 10 as well as Fig.14 Various schematic diagrams of an embodiment in which the support structure 33 is disposed between the first wall 311 and the electrode assembly 32 are shown. Figures 11 to 13 as well as Fig.15 , Fig.18 and Fig.19 Various schematic diagrams of an embodiment in which the support structure 33 is disposed between the second wall 313 and the electrode assembly 32 are shown. Fig. 20 A schematic diagram of an embodiment in which the support structure is disposed between a third wall 315 of the housing 31 disposed opposite to the first wall 311 and the electrode assembly 32 is shown.

[0164] Alternatively, if Figures 5 to 10 as well as Fig.14 As shown, the support structure 33 includes a first support member 331 disposed between the first wall 311 and the electrode assembly 32 .

[0165] In this embodiment, by setting the first support member 331 between the first wall 311 and the electrode assembly 32, the electrode assembly 32 can be directly limited. When the battery cell 30 has thermal runaway, the electrode assembly 32 can be prevented from moving toward the first wall 311, so that the thermal runaway gas can reach the pressure relief mechanism 312 through the exhaust channel A formed between the first wall 311 and the electrode assembly 32, and then can be discharged from the pressure relief mechanism 312 to the battery cell 30 in time, thereby reducing the possibility of non-directional pressure relief in the battery cell 30.

[0166] In one embodiment, if Figure 5 As shown, the first support member 331 is fixedly connected to the first wall 311 , that is, the first support member 331 is fixed to the surface of the first wall 311 facing the electrode assembly 32 .

[0167] In an example, the material of the first support member 331 includes a metal material, and the first support member 331 and the first wall 311 can be fixedly connected by welding.

[0168] In another example, the material of the first support member 331 includes a hard material such as a non-metal, and the first support member 331 and the first wall 311 can be fixedly connected by bonding or other methods.

[0169] In this embodiment, the first support member 331 is fixedly connected to the first wall 311 so as to be disposed between the first wall 311 and the electrode assembly 32. On the one hand, the movement of the first support member 331 in the battery cell 30 can be reduced, and the probability of the first support member 331 blocking the pressure relief mechanism 312 is reduced. On the other hand, an exhaust channel A connected to the pressure relief mechanism 312 can be formed between the first wall 311 and the electrode assembly 32, which can reduce the possibility of non-directional pressure relief of the battery cell 30.

[0170] In another embodiment, the first support member 331 may be integrally formed with the first wall 311 .

[0171] In this embodiment, the first support member 331 and the first wall 311 are integrally formed, which can improve the bonding strength between the first wall 311 and the first support member 331 , further reduce the movement of the first support member 331 in the battery cell 30 , and reduce the probability of the first support member 331 blocking the pressure relief mechanism 312 .

[0172] In some examples, the first wall 311 may be an end cap.

[0173] In this embodiment, the first support member 331 is fixed together with the end cover. Compared with fixing the first support member 331 to other walls of the outer shell, the first support member 331 can be fixed together with the end cover externally, or the first support member 331 can be directly formed when preparing the end cover, without extending the first support member 331 into the outer shell 31 for fixing, thereby improving the preparation efficiency of the battery cell 30.

[0174] Continue to see Figure 5 ,like Figure 5 As shown, the battery cell 30 further includes: a first insulating member 34 disposed between the electrode assembly 32 and the first wall 311 ; wherein the first insulating member 34 is provided with an escape cavity 341 , and the escape cavity 341 is used to accommodate the first support member 331 .

[0175] Typically, the first insulating member 34 is disposed between the first wall 311 and the electrode assembly 32, and is used to insulate the first wall 311 from the electrode assembly 32, so as to achieve electrical isolation between the first wall 311 and the electrode assembly 32. Optionally, the material of the first insulating member 34 may include at least one material such as a polypropylene (PP) material, a polyphenylene sulfide (PPS) material, or a soluble polytetrafluoroethylene (PFA) material.

[0176] Optionally, the first insulating member 34 may be provided with an escape cavity 341 opening toward the first wall 311 , so that the first support 331 fixed to the surface of the first wall 311 facing the electrode assembly 32 may be accommodated in the escape cavity 341 .

[0177] In this embodiment, by providing an avoidance cavity 341 on the first insulating member 34 to accommodate the first support member 331, it is possible to increase the energy density of the battery cell 30 without occupying additional space of the battery cell 30 in the thickness direction Z of the first wall 311 without affecting the insulation between the first wall 311 and the electrode assembly 32.

[0178] In other embodiments, the first support member 331 may be fixedly connected to the first wall 311 , or the first support member 331 may be fixed in the avoidance cavity 341 .

[0179] Optionally, the melting point of the first support 331 is higher than the melting point of the first insulating member 34 .

[0180] Generally, in the later stage of thermal runaway, the first insulating member 34 may be melted, which will cause the electrode assembly 32 to move toward the first wall 311, or even to abut against the first wall 311. This blocks the exhaust passage for the thermal runaway gas to reach the pressure relief mechanism 312. In this embodiment, by setting the melting point of the first support member 331 to be higher than the melting point of the first insulating member 34, the first support member 331 is not easily melted in the later stage of thermal runaway, and can provide an exhaust passage A for the thermal runaway gas to reach the pressure relief mechanism 312, thereby reducing the probability of non-directional pressure relief of the battery cell 30.

[0181] In other embodiments, the first support member 331 is disposed between the first wall 311 and the electrode assembly 32 , and the first support member 331 is fixed together with the first insulating member 34 .

[0182] For example, Figure 8 As shown, the first insulating member 34 may be provided with a relief cavity 341 opening toward the electrode assembly 32, and the first support member 331 may be fixed in the relief cavity 341 by interference fit. Alternatively, regardless of whether the relief cavity 341 opens toward the first wall 311 or the electrode assembly 32, the first support member 331 may be fixed in the relief cavity 341 by bonding.

[0183] In some examples, the first support member 331 may be in contact with the first wall 311. In other examples, there is a certain gap between the first support member 331 and the first wall 311.

[0184] In this embodiment, by fixing the first support member 331 in the avoidance cavity 341 of the first insulating component 34, on the one hand, the movement of the first support member 331 in the battery cell 30 can be reduced, thereby reducing the probability of the first support member 331 blocking the pressure relief mechanism 312; on the other hand, there is no need to occupy additional space of the battery cell 30 in the thickness direction Z of the first wall 311, thereby improving the energy density of the battery cell 30.

[0185] Alternatively, if Figure 5 , Figures 7 to 10 As shown, in the thickness direction Z of the first wall 311 , the projection of the first support member 331 on the first wall 311 is arranged at an end region of the first wall 311 along a first direction, and the first direction is perpendicular to the thickness direction Z of the first wall 311 .

[0186] It should be noted that the first support member 331 in the embodiment of the present application is located in the end area of ​​the first wall 311 in the first direction compared to the pressure relief mechanism 312. For example, the battery cell 30 includes two first support members 331. The projections of the two first support members 331 on the first wall 311 are respectively arranged at the two ends of the first wall 311 along the first direction, and the pressure relief mechanism 312 is arranged between the two first support members 331.

[0187] In this embodiment, in the thickness direction Z of the first wall 311, the projection of the first support member 331 on the first wall 311 is arranged in the end area of ​​the first wall 311 in the first direction, which can minimize the possibility of the first wall 311 at the end in the first direction abutting against the electrode assembly 32, so that the thermal runaway gas in the battery cell 30 can reach the pressure relief mechanism 312, thereby reducing the possibility of non-directional pressure relief of the battery cell 30.

[0188] In one example, the battery cell 30 is a square battery cell, and the first direction may be the length direction Z of the first wall 311 or the width direction of the first wall 311. Specifically, a first support member 331 may be provided at each of the two ends of the first wall 311 along the length direction X and / or the two ends along the width direction Y.

[0189] In another example, the battery cell 30 is a cylindrical battery cell, and the first direction is a radial direction of the first wall 311. Specifically, along the circumference of the first wall 311, the first support members 331 are distributed at intervals at the end of the first wall 311.

[0190] Furthermore, if Figures 5 to 7 as well as Fig. 9 As shown, in the first direction, there is a gap 36 between the electrode assembly 32 and the housing 31 , and the first support member 331 is provided with a first cavity 35 penetrating along the first direction, and the first cavity 35 is used to connect the gap 36 and the pressure relief mechanism 312 .

[0191] In this embodiment, the first support member 331 is provided with a first cavity 35 extending along the first direction, which is used to connect the gap 36 and the pressure relief mechanism 312, so as to guide the thermal runaway gas accumulated in the gap 36 to the pressure relief mechanism 312, thereby reducing the possibility that the thermal runaway gas accumulated in the gap 36 will not have time to be exhausted and cause the shell 31 to be broken.

[0192] In one example, if Figure 6 As shown, the first support member 331 is provided with at least one first through hole 351 penetrating along the first direction, and the first cavity 35 includes the at least one first through hole 351 .

[0193] Optionally, the first support member 331 is provided with a plurality of first through holes 351, and the plurality of first through holes 351 may be spaced apart along a second direction, and the second direction is perpendicular to both the thickness direction Z of the first wall 311 and the first direction. For example, the first direction is the length direction X of the first wall 311, and the second direction is the width direction Y of the first wall 311. For another example, the first direction is the width direction Y of the first wall 311, and the second direction is the length direction X of the first wall 311.

[0194] Optionally, the first support member 331 may also be provided with a large first through hole 351 to increase the ventilation area as much as possible, while also being able to reduce the weight of the battery cell 30 and improve the energy density of the battery cell 30 .

[0195] In this embodiment, by providing at least one first through hole 351 extending along the first direction in the first support member 331 to form a first cavity 35, on the one hand, the possibility of the thermal runaway gas accumulated in the gap 36 not being able to be exhausted in time and causing the outer shell 31 to be broken can be reduced; on the other hand, the weight of the battery cell 30 can also be reduced, and the energy density of the battery cell 30 can be improved.

[0196] In another example, Figure 7 As shown, the first support member 331 includes a plurality of first support blocks 3310 spaced apart in a second direction, and the first cavity 35 includes a space 352 between every two adjacent first support blocks 3310 among the plurality of first support blocks 3310, wherein the second direction is perpendicular to both the thickness direction of the first wall 311 and the first direction.

[0197] In this embodiment, a plurality of first support blocks 3310 are spaced apart in the second direction to form a first cavity 35. On the one hand, the possibility that the thermal runaway gas accumulated in the gap 36 cannot be exhausted in time and the outer shell 31 may be ruptured can be reduced; on the other hand, the weight of the battery cell 30 can be reduced and the energy density of the battery cell 30 can be improved.

[0198] Alternatively, if Fig. 9 As shown, in the thickness direction Z of the first wall 311 , the dimension h of the first support member 331 and the dimension c of the battery cell satisfy: 0.003≤h / c≤0.13.

[0199] In this embodiment, if h / c is less than 0.003, it is very easy to be blocked by particulate matter or pole pieces generated by the loss of control inside the battery cell 30, thereby failing to achieve the purpose of forming the exhaust channel A; and when h / c is greater than 0.13, the energy density of the battery cell 30 will be seriously sacrificed; setting h / c between 0.003 and 0.13 can achieve the purpose of balancing the energy density of the battery cell 30 and forming the exhaust channel A between the first wall 311 and the electrode assembly 32.

[0200] The technical effect achieved by 0.003≤h / c≤0.13 will be described in detail below with reference to specific embodiments.

[0201] Specifically, the size of the battery cell shell is 44mm*220mm*100mm (width*length*height), the energy density is 250Wh / kg, and the end cap (for example, the first wall) with the first support is manufactured by machine punching. The end cap has a pressure relief mechanism, wherein the first support is two regular quadrangular prisms, symmetrically distributed, respectively located at the two ends of the short side of the end cap, with a length of 41mm, and 0.5mm from the long side of the end cap, and the distance from the first support to the short side of the end cap is 7mm. The first support of different heights is made respectively, and then the battery cell is triggered to lose control through the built-in heating film, and the directional pressure relief of the battery cell is observed. The valve opening pressure of the pressure relief mechanism is 1.0MPa, and the end cap weld strength is 1.5MPa; at the same time, the air pressure inside the battery cell is detected through the end cap and the side air pipe, and the data is shown in Table 1.

[0202] Table 1

[0203]

[0204]

[0205] It can be seen from Table 1 that when h / c = 0.001 and 0.002, the side weld of the shell fails; when h / c = 0.135, the pressure relief mechanism opens normally and the shell is intact, but the energy density loss is serious; and when h / c = 0.003, 0.01, 0.02, 0.05, 0.1 and 0.13, the pressure relief mechanism opens normally and the shell is intact.

[0206] Further optionally, 0.03≤h / c≤0.08.

[0207] Alternatively, if Fig.10As shown, a plurality of first support members 331 are arranged between the first wall 311 and the electrode assembly 32. In the thickness direction Z of the first wall 311, the plurality of first support members 331 satisfy the following relationship between the total projected area S1 of the first wall 311 and the area S of the first wall: 0.012≤S1 / S≤0.26.

[0208] In this embodiment, when S1 / S is less than 0.012, when thermal runaway occurs in the battery cell 30, the contact area between the first support member 331 and the first wall 311 is too small, which cannot provide sufficient mechanical support for the electrode assembly 32, which may cause the internal electrode assembly 32 to shake or overlap with the first wall 311, and even further deteriorate the exhaust path; and when S1 / S is greater than 0.26, on the one hand, the weight of the battery cell will increase, sacrificing energy density, and on the other hand, the first support member 331 will further reduce the internal free space of the battery cell 30, which is not conducive to directional pressure relief. Setting S1 / S between 0.012 and 0.26 can achieve the purpose of balancing the energy density of the battery cell 30 and forming an exhaust channel A between the first wall 311 and the electrode assembly 32.

[0209] The technical effect achieved by 0.012≤S1 / S≤0.26 will be described in detail below with reference to specific embodiments.

[0210] Specifically, the size of the battery cell shell is 44mm*220mm*100mm (width*length*height), the energy density is 250Wh / kg, and the end cap (for example, the first wall) with the first support is manufactured by machine punching. The end cap has a pressure relief mechanism, wherein the first support is two regular quadrangular prisms, which are symmetrically distributed and located at the two ends of the short side of the end cap, respectively, with a length of 41mm and a height of 1mm. The width is used as a variable to adjust S1, and then the battery cell is triggered to lose control through the built-in heating film, and the directional pressure relief of the battery cell is observed. The valve opening pressure of the pressure relief mechanism is 1.0MPa, and the end cap weld strength is 1.5MPa; at the same time, the air pressure inside the battery cell is detected through the end cap and the side air pipe, and the data is shown in Table 2.

[0211] Table 2

[0212]

[0213] It can be seen from Table 2 that when S1 / S=0.0042, the end cover weld fails; when S1 / S=0.0085, the side weld fails; when S1 / S=0.3 and 0.31, the side weld fails; and when S1 / S=0.012, 0.013, 0.021, 0.053, 0.11, 0.22 and 0.26, the pressure relief mechanism opens normally and the shell is intact.

[0214] Further optionally, 0.08≤S1 / S≤0.2.

[0215] like Figures 11 to 13 , Fig.15 as well as Fig.18 and Fig.19 As shown, the housing 31 further has a second wall 313 , which intersects with the first wall 311 , and the support structure 33 is disposed between the second wall 313 and the electrode assembly 32 .

[0216] Optionally, the second wall 313 intersects with the first wall 311, which means that the second wall 313 and the first wall 311 are at a preset angle. For example, the second wall 313 and the first wall 311 are 90 degrees, or the two are perpendicular to each other. In other embodiments, the second wall 313 and the first wall 311 may also be at other angles, for example, 75 degrees. This embodiment of the present application is not limited to this.

[0217] In some embodiments, the battery cell 30 is a square battery cell, and the second wall 313 includes a wall of the housing 31 perpendicular to the length direction X of the first wall 311 , and / or the second wall 313 includes a wall of the housing 31 perpendicular to the width direction Y of the first wall 311 .

[0218] In other embodiments, the battery cell 30 is a cylindrical battery cell, and the second wall 313 may include a side wall of the housing 31 .

[0219] Alternatively, if Figures 11 to 13 As shown, the second support member 332 is fixedly connected to the second wall 313 .

[0220] Optionally, the second support member 332 may be fixedly connected to the second wall 313 by welding. Alternatively, the second support member 332 may be fixedly connected to the second wall 313 by other means such as clamping, bonding or riveting.

[0221] In this embodiment, a second support member 332 is fixedly provided on a second wall 313 of the outer shell 31 which is perpendicular to the first wall 311 to support the electrode assembly 32. This helps prevent the end of the electrode assembly 32 from moving toward the first wall 311 when thermal runaway occurs in the battery cell 30. This increases the probability of forming an exhaust channel A between the first wall 311 and the electrode assembly 32 when thermal runaway occurs in the battery cell 30.

[0222] In some other embodiments, the first support member 331 and the second support member 332 may be combined. Figures 5 to 10 The first support member 331 shown in the figure further comprises Fig.11 The second support member 332 is shown.

[0223] Continue to see Fig.11The second wall 313 forms a receiving space with an opening 314 , the first wall 311 covers the opening 314 to dispose the electrode assembly 32 in the receiving space, and the second support member 332 is disposed at the opening 314 .

[0224] In this embodiment, by setting the second support member 332 at the opening 314 of the accommodating space formed by the second wall 313, the possibility of blocking the end of the electrode assembly 32 from moving toward the first wall 311 can be increased, thereby increasing the probability of forming an exhaust channel A between the first wall 311 and the electrode assembly 32 when thermal runaway occurs in the battery cell 30.

[0225] In other examples, the second support member 332 may be disposed between the surface of the electrode assembly 32 parallel to the second wall 313 and the second wall 313, and in the thickness direction Z along the first wall 311, the second support member 332 may be located at different positions of the second wall 313. For example, in the thickness direction Z along the first wall 311, the second support member 332 may be disposed in a region of the second wall 313 away from the first wall 311. For another example, in the thickness direction Z along the first wall 311, the second support member 332 may be disposed in a middle region of the second wall 313. In this embodiment, the presence of the second support member 332 may cause a gap to exist between the electrode assembly 32 and the second wall 313 of the housing 31, and the gap may be as shown in FIG. Fig. 9 The gap 36 shown. That is, Fig. 9 The gap 36 in the middle can be formed by the second support member 332.

[0226] Alternatively, if Fig.12 As shown, the second support member 332 is provided with a second cavity 37 penetrating along the thickness direction Z of the first wall 311 , and the second cavity 37 is used to guide the thermal runaway gas accumulated between the second wall 313 and the electrode assembly 32 to the exhaust channel A.

[0227] In this embodiment, by providing the second support member 332 with a second cavity 37 that passes through the first wall 311 in the thickness direction Z, the electrode assembly 32 can be supported by the second support member 332 to reduce the possibility of the end of the electrode assembly 32 moving toward the first wall 311, and the thermal runaway gas accumulated between the second wall 313 and the electrode assembly 32 can be guided to the exhaust channel A through the second cavity 37, thereby reducing the possibility of non-directional pressure release of the battery cell 30.

[0228] It should be noted that the implementation of the second cavity 37 of the second support member 332 may refer to the first cavity 35 of the first support member 331 .

[0229] For example, Fig.12As shown, the second support member 332 includes a plurality of second support blocks 3320 spaced apart along the circumferential direction of the opening 314 , and the second cavity 37 includes a space 371 between every two adjacent second support blocks 3320 in the plurality of second support blocks 3320 .

[0230] For another example, at least one through hole penetrating the first wall 311 along the thickness direction Z may be provided in the second support member 332. The second cavity 37 includes the at least one through hole.

[0231] In some embodiments, along the thickness direction Z of the first wall 311 , the plurality of second support blocks 3320 may not be disposed at the opening 314 . In other embodiments, along the thickness direction Z of the first wall 311 , the plurality of second support blocks 3320 may also be disposed at different positions of the second wall 313 .

[0232] In this embodiment, a plurality of second support blocks 3320 are arranged at intervals along the circumference of the opening 314 to form a second cavity 37, which can reduce the possibility that the thermal runaway gas accumulated between the second wall 313 and the electrode assembly 32 will not be exhausted in time and cause the shell 31 to be broken.

[0233] In an example, if the battery cell 30 is a square battery cell, the second wall 313 may only include side walls that are oppositely arranged along the length direction X, or the second wall 313 may only include side walls that are oppositely arranged along the width direction Y.

[0234] Alternatively, if Fig.13 As shown, in the thickness direction Z of the first wall 311, the surface 3321 of the second support member 332 away from the first wall 311 is closer to the first wall 311 than the surface 320 of the electrode assembly 32 close to the first wall 311; and in the thickness direction Z of the first wall 311, the projection of the second support member 332 on the first wall 311 and the projection of the electrode assembly 32 on the first wall 311 have an intersection.

[0235] In this embodiment, in the thickness direction Z of the first wall 311, the second support member 332 has an intersection between the projection of the first wall 311 and the projection of the electrode assembly 32 on the first wall 311, and the second support member 332 is closer to the first wall 311 than the electrode assembly 32, so that when thermal runaway occurs in the battery cell 30, the second support member 332 can block the electrode assembly 32 from approaching the first wall 311, thereby forming an exhaust channel A between the first wall 311 and the electrode assembly 32, reducing the possibility of non-directional pressure relief in the battery cell 30.

[0236] like Figure 8 as well as Figures 14 to 19As shown, the battery cell 30 also includes: an insulating component 40, which is arranged between the outer shell 31 and the electrode component 32, and is used to insulate the outer shell 31 and the electrode component 32; the supporting structure 33 includes a third support member 333, and the third support member 333 is fixedly connected to the insulating component 40, and the third support member 333 is arranged between the outer shell 31 and the insulating component 40.

[0237] In this embodiment, a third support member 333 is provided between an insulating assembly 40 disposed between the outer shell 31 and the electrode assembly 32, and the third support member 333 is fixedly connected to the insulating assembly 40 to support the electrode assembly 32. This helps to reduce the possibility of the electrode assembly 32 moving toward the first wall 311 when thermal runaway occurs in the battery cell, thereby increasing the probability of forming an exhaust channel A between the first wall 311 and the electrode assembly 32.

[0238] In one embodiment, if Figure 8 As shown, the insulating assembly 40 includes a first insulating member 34, which is disposed between the first wall 311 and the electrode assembly 32. In this case, the third support member can be a first support member 331, which is fixedly connected to the first insulating member 34. This embodiment can refer to Figure 8 For the sake of brevity, the description is not repeated here.

[0239] In another embodiment, if Figures 14 to 19 As shown, the insulating assembly 40 includes a second insulating component 38 coated on the outer surface of the electrode assembly 32 ; and a third support member 333 is fixedly connected to the second insulating component 38 .

[0240] In order to better isolate the electrode assembly 32 from the housing 31, an insulating film is usually coated on the outer surface of the electrode assembly 32, that is, the second insulating member 38 in the embodiment of the present application. For example, the second insulating member 38 can be a mylar film.

[0241] Alternatively, if Fig.14 As shown, the third support member 333 may be fixedly disposed on a surface of the second insulating member 38 perpendicular to the thickness direction Z of the first wall 311 and closer to the first wall 311 , so that the third support member 333 is disposed between the first wall 311 and the electrode assembly 32 .

[0242] Alternatively, if Fig.15 As shown, the third support member 333 may also be fixedly disposed on a surface of the second insulating member 38 that is perpendicular to the first wall 311 , so that the third support member 333 is disposed between the second wall 313 and the electrode assembly 32 .

[0243] In this embodiment, by fixing the third support member 333 to the second insulating member 38 covering the outer surface of the electrode assembly 32 to support the electrode assembly 32, the possibility of the electrode assembly 32 moving toward the first wall 311 is reduced when thermal runaway occurs in the battery cell 30, thereby increasing the probability of forming an exhaust channel A between the first wall 311 and the electrode assembly 32.

[0244] In one example, when the third support member 333 is fixedly disposed on a surface of the second insulating member 38 that is perpendicular to the first wall 311, the presence of the third support member 333 allows a gap to exist between the second wall 313 and the second insulating member 38, that is, Figure 4 The gap 36 shown may be realized by a third support member 333 .

[0245] In another example, when the third support member 333 is fixedly disposed on a surface of the second insulating member 38 that is perpendicular to the thickness direction Z of the first wall 311 and closer to the first wall 311, Figure 5 The opening of the avoidance cavity 341 in the second insulating member 34 shown may face the electrode assembly 32 , and the third support member 333 is accommodated in the avoidance cavity 341 .

[0246] Alternatively, if Fig.18 As shown, the third support member 333 has a second through hole 3332 , and the second through hole 3332 is used to release the thermal runaway gas generated by the electrode assembly 32 to between the second insulating member 38 and the housing 31 .

[0247] Optionally, the second through hole 3332 may also be used for infiltrating electrolyte.

[0248] In this embodiment, by setting a second through hole 3332 in the third support member 333, the thermal runaway gas generated by the electrode assembly 32 can be released in time between the second insulating member 38 and the outer shell 31, so that the thermal runaway gas can be further guided to the exhaust channel A, so that the thermal runaway gas can be discharged through the pressure relief mechanism 312.

[0249] Alternatively, if Fig.19 As shown, the third support member 333 is provided with a groove 3333 opening toward the housing 31 .

[0250] Optionally, the cross-sectional shape of the groove 3333 may be circular or square, which is not limited in the embodiment of the present application.

[0251] In some embodiments, the second through hole 3332 and the groove 3333 may also be combined with each other. For example, the second through hole 3332 is provided on the bottom wall of the groove 3333 .

[0252] In this embodiment, by providing a groove 3333 with an opening toward the housing 31 on the third support member 333 , on the one hand, the accommodation space for the thermal runaway gas can be increased, and on the other hand, the weight of the battery cell 30 can be reduced, thereby improving the energy density of the battery cell 30 .

[0253] In one example, if Fig.16 As shown, the third support member 333 and the insulating assembly 40 can be fixedly connected by a snap-fitting manner. For example, the third support member 333 is provided with a protrusion, and the second insulating member is provided with a groove or a through hole, and the two cooperate with each other.

[0254] In this embodiment, the third support member 333 is fixedly connected to the insulating assembly 40 by snapping, which can improve the bonding strength between the third support member 333 and the insulating assembly 40 and reduce the probability of the third support member 333 moving inside the battery cell 30 to block the exhaust channel A.

[0255] In another example, Fig.17 As shown, the third support member 333 and the insulating assembly 40 can be fixedly connected by bonding. For example, the third support member 333 and the insulating assembly 40 are fixedly connected by a fixing glue 39.

[0256] In this embodiment, the third support member 333 and the insulating assembly 40 can be fixedly connected by bonding, which can improve the bonding strength between the third support member 333 and the insulating assembly 40 and reduce the probability of the third support member 333 moving inside the battery cell 30 to block the exhaust channel A.

[0257] like Fig. 20 As shown, the battery cell 30 also includes a support plate 41, which is arranged below the electrode assembly 32 along the gravity direction G, and the support structure 33 includes a fourth support member 334, which is arranged below the electrode assembly 32 along the gravity direction G, and the melting point of the fourth support member 334 is higher than the melting point of the support plate 41.

[0258] The support plate 41, also referred to as a bottom guard plate, is generally a flat plate structure and is disposed at the bottom of the battery cell to support and protect the electrode assembly.

[0259] Optionally, the fourth support member 334 may be disposed between the electrode assembly 32 and the support plate 41 , or between the support plate 41 and the wall of the housing 31 .

[0260] In some embodiments, the gravity direction G may also be considered as the thickness direction Z of the first wall 311. In this case, the first wall 311 may be a wall closer to the support plate 41 along the gravity direction G, for example, the first wall 311 may be the bottom wall of the housing 31. Alternatively, the first wall 311 may also be a wall of the housing 31 farther from the support plate 41 along the gravity direction G, for example, the first wall 311 may be the top wall of the housing 31.

[0261] In addition, the support plate 41 may be a metal material or other material capable of supporting the electrode assembly 32. In the embodiment of the present application, the melting point of the fourth support member 334 is higher than that of the support plate 41, so that when the battery cell 30 undergoes thermal runaway, even if the support plate 41 is melted, the fourth support member 334 is not easily melted, and can still play a role in supporting the electrode assembly 32, and form a space to accommodate the thermal runaway gas, thereby reducing the possibility of non-directional pressure relief of the battery cell 30.

[0262] Optionally, the fourth support member 334 is fixedly connected to the support plate 41 .

[0263] In this embodiment, by fixedly connecting the fourth support member 334 to the support plate 41 , a space for accommodating thermal runaway gas is formed between the electrode assembly 32 and the support plate 41 , thereby reducing the possibility of non-directional pressure release of the battery cell 30 .

[0264] In other embodiments, the fourth support member 334 may also be fixedly connected to a wall of the housing 31 disposed opposite to the first wall 311 along the thickness direction Z of the first wall 311. For example, the fourth support member 334 may be fixedly connected to the bottom wall of the housing 31.

[0265] It should be noted that the first support member 331 , the second support member 332 , the third support member 333 and the fourth support member 334 in the embodiment of the present application can be combined with each other, and the embodiment of the present application is not limited to this.

[0266] Alternatively, if Figure 5 , Fig.11 , Fig.14 and Fig.15 As shown, the battery cell 30 further includes: an electrode terminal 316 disposed on the first wall 311 , and the electrode terminal 316 is electrically connected to the electrode assembly 32 .

[0267] In this embodiment, by electrically connecting the electrode terminal 316 provided on the first wall 311 and the electrode assembly 32 , electrical connection with other battery cells can be achieved, thereby achieving the purpose of expanding the battery capacity.

[0268] Optionally, in some embodiments, the electrode terminal 316 may be disposed on a side of the first wall 311 away from the electrode assembly 32 , so as to reduce the internal space occupied by the battery cell 30 and improve the energy density of the battery cell 30 .

[0269] See again Figures 4 to 20 The battery cell 30 includes: a housing 31 having a first wall 311, the first wall 311 being provided with an electrode terminal 316 and a pressure relief mechanism 312, the electrode terminal 316 being provided outside the housing 31; an electrode assembly 32 being accommodated in the housing 31 and electrically connected to the electrode terminal 316; a support structure 33 being provided between the electrode assembly 32 and the housing 31, the support structure 33 being used to form an exhaust channel A between the first wall 311 and the electrode assembly 32 and communicating with the pressure relief mechanism 312. The support structure 33 includes a first support member 331 provided between the first wall 311 and the electrode assembly and fixed to the first wall 311, and a second support member 332 provided between the second wall 313 of the housing 31 and the electrode assembly 32 and fixed to the second wall 313, wherein the second wall 313 is perpendicular to the first wall 311. The battery cell 30 further includes a first insulating member 34, which is disposed between the electrode assembly 32 and the first wall 311. The first insulating member 34 is provided with an avoidance cavity 341, and the avoidance cavity 341 is used to accommodate the first support member 331. The melting point of the first support member 331 is higher than the melting point of the first insulating member 34. In the thickness direction Z of the first wall 311, the projection of the first support member 331 on the first wall 311 is disposed at the end region of the first wall 311 along the first direction, and the first direction is perpendicular to the thickness direction Z of the first wall 311. In the first direction, there is a gap 36 between the electrode assembly 32 and the housing 31, and the first support member 331 is provided with a first cavity 35 that penetrates along the first direction, and the first cavity 35 is used to connect the gap 36 and the pressure relief mechanism 312.

[0270] In this embodiment, a first support member 331 is provided between the first wall 311 and the electrode assembly 32 to support the electrode assembly 32, so that an exhaust channel A is formed between the first wall 311 and the electrode assembly 32 to guide the thermal runaway gas to the pressure relief mechanism 312. The thermal runaway gas can be discharged through the pressure relief mechanism 312 in a timely manner, thereby reducing the probability of non-directional pressure relief of the battery cell 30. In addition, by arranging the second support member 332 between the second wall 313 and the electrode assembly 32, a gap 36 for accommodating the thermal runaway gas can be formed between the second wall 313 and the electrode assembly 32, and the gap 36 is connected to the pressure relief mechanism 312 through the first cavity 35 arranged by the first support member 331, so that the thermal runaway gas can be discharged through the pressure relief mechanism 312 in time, thereby reducing the probability of non-directional pressure relief of the battery cell 30; in addition, by accommodating the first support member 331 in the avoidance cavity 341 of the first insulating member 34, the energy density of the battery cell 30 can be improved, and since the melting point of the first support member 331 is higher than the melting point of the first insulating member 34, when the battery cell 30 undergoes thermal runaway, even if the first insulating member 34 melts and causes the electrode assembly 32 to move close to the first wall 311, the first support member 331 will not melt to block the movement of the electrode assembly 32, so that an exhaust channel for guiding the thermal runaway gas to the pressure relief mechanism 312 can still be formed between the first wall 311 and the electrode assembly 32.

[0271] Optionally, the battery cell 30 may further include other components, such as Figure 3 For the sake of brevity, the connecting member 23 shown is not described in detail here.

[0272] The embodiment of the present application further provides a battery, which includes at least one battery cell 30 of the embodiment of the present application.

[0273] An embodiment of the present application further provides an electrical device, comprising the battery of the above embodiment, wherein the battery is used to provide electrical energy to the electrical device.

[0274] The electrical device can be Figure 1 The vehicle shown may also be any device using a battery.

[0275] Although the present application has been described with reference to preferred embodiments, various modifications may be made thereto and parts thereof may be replaced with equivalents without departing from the scope of the present application. In particular, the various technical features mentioned in the various embodiments may be combined in any manner as long as there are no structural conflicts. The present application is not limited to the specific embodiments disclosed herein, but includes all technical solutions falling within the scope of the claims.

Claims

1. A battery cell, characterized in that: include: The housing has a first wall, wherein the first wall is provided with a pressure relief mechanism; an electrode assembly, contained in the housing; A support structure is arranged between the shell and the electrode assembly, and the support structure is used to form an exhaust channel connected to the pressure relief mechanism between the first wall and the electrode assembly.

2. The battery cell according to claim 1, characterized in that: The supporting structure is used to support the electrode assembly.

3. The battery cell according to claim 1 or 2, characterized in that: The melting point of the support structure is greater than 100°C.

4. The battery cell according to any one of claims 1 to 3, characterized in that: The support structure includes a first support member disposed between the first wall and the electrode assembly.

5. The battery cell according to claim 4, characterized in that: The first supporting member is fixedly connected to the first wall.

6. The battery cell according to claim 4, characterized in that: The first support member is integrally formed with the first wall.

7. The battery cell according to any one of claims 4 to 6, characterized in that: The battery cell further comprises: a first insulating member disposed between the electrode assembly and the first wall; Wherein, the first insulating component is provided with an avoidance cavity, and the avoidance cavity is used to accommodate the first support member.

8. The battery cell according to any one of claims 4 to 7, characterized in that: The battery cell further includes a first insulating member for insulating the first wall and the electrode assembly, and the first support has a higher melting point than that of the first insulating member.

9. The battery cell according to any one of claims 4 to 8, characterized in that: In the thickness direction of the first wall, a projection of the first support member on the first wall is arranged at an end region of the first wall along a first direction, and the first direction is perpendicular to the thickness direction of the first wall.

10. The battery cell according to claim 9, characterized in that: In the first direction, there is a gap between the electrode assembly and the housing, and the first support member is provided with a first cavity penetrating along the first direction, and the first cavity is used to connect the gap and the pressure relief mechanism.

11. The battery cell according to claim 10, characterized in that: The first support member is provided with at least one first through hole penetrating along the first direction, and the first cavity includes the at least one first through hole.

12. The battery cell according to claim 10, characterized in that: The first support member includes a plurality of first support blocks spaced apart in a second direction, the first cavity includes a space between every two adjacent first support blocks among the plurality of first support blocks, the second direction is perpendicular to a thickness direction of the first wall, and the second direction is perpendicular to the first direction.

13. The battery cell according to any one of claims 4 to 12, characterized in that: In the thickness direction of the first wall, a dimension h of the first support member and a dimension c of the battery cell satisfy the following relationship: 0.003≤h / c≤0.

13.

14. The battery cell according to any one of claims 4 to 13, characterized in that: At least one first support member is arranged between the first wall and the electrode assembly. In the thickness direction of the first wall, the total projected area S1 of the at least one first support member on the first wall and the area S of the first wall satisfy: 0.012≤S1 / S≤0.

26.

15. The battery cell according to any one of claims 1 to 14, characterized in that: The housing further comprises a second wall intersecting with the first wall, and the supporting structure comprises a second supporting member fixedly connected with the second wall.

16. The battery cell according to claim 15, characterized in that: The second wall forms a receiving space with an opening, the first wall covers the opening to arrange the electrode assembly in the receiving space, and the second support member is arranged at the opening.

17. The battery cell according to claim 16, characterized in that: The second support member is provided with a second cavity penetrating along a thickness direction of the first wall, and the second cavity is used to guide the thermal runaway gas accumulated between the second wall and the electrode assembly to the exhaust channel.

18. The battery cell according to claim 17, characterized in that: The second support member includes a plurality of second support blocks arranged at intervals along the circumferential direction of the opening, and the second cavity includes an interval between every two of the plurality of second support blocks.

19. The battery cell according to any one of claims 15 to 18, characterized in that: In the thickness direction of the first wall, a surface of the second support member away from the first wall is closer to the first wall than a surface of the electrode assembly close to the first wall; In the thickness direction of the first wall, the second support member has an intersection between a projection of the second support member on the first wall and a projection of the electrode assembly on the first wall.

20. The battery cell according to any one of claims 1 to 19, characterized in that: The battery cell further comprises: An insulating assembly, disposed between the housing and the electrode assembly, for insulating the housing from the electrode assembly; The supporting structure comprises a third supporting member, the third supporting member is fixedly connected to the insulating assembly, and the third supporting member is arranged between the housing and the insulating assembly.

21. The battery cell according to claim 20, characterized in that: The insulating assembly includes a first insulating member, the first insulating member is disposed between the first wall and the electrode assembly, and the third support is fixedly connected to the first insulating member.

22. The battery cell according to claim 20 or 21, characterized in that: The insulating assembly includes a second insulating component, the second insulating component is coated on the outer surface of the electrode assembly, and the third support is fixedly connected to the second insulating component.

23. The battery cell according to claim 22, characterized in that: The third support member has a second through hole, and the second through hole is used to release the thermal runaway gas generated by the electrode assembly to between the insulation assembly and the housing.

24. The battery cell according to claim 22 or 23, characterized in that: The third support member is provided with a groove opening toward the housing.

25. The battery cell according to any one of claims 20 to 24, characterized in that: The third support member is fixedly connected to the insulating assembly by means of a snap connection.

26. The battery cell according to any one of claims 20 to 24, characterized in that: The third support member is fixedly connected to the insulating assembly by bonding.

27. The battery cell according to any one of claims 1 to 26, characterized in that: The battery cell further comprises: A support plate, disposed between the electrode assembly and the housing, and located below the electrode assembly in the direction of gravity; The support structure includes a fourth support member disposed below the electrode assembly along the gravity direction, and the melting point of the fourth support member is higher than the melting point of the support plate.

28. The battery cell according to claim 27, characterized in that: The fourth support member is fixedly connected to the support plate.

29. The battery cell according to any one of claims 1 to 28, characterized in that: The first wall is an end cap.

30. The battery cell according to any one of claims 1 to 29, characterized in that: The battery cell further comprises: An electrode terminal, disposed on the first wall; The electrode terminal is electrically connected to the electrode assembly.

31. A battery, characterized in that: The invention comprises the battery cell according to any one of claims 1 to 30.

32. An electrical device, characterized in that: Comprising the battery as claimed in claim 31, wherein the battery is used to provide electrical energy to the electrical device.

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