Battery monomer, battery and electric device

Abstract

The utility model provides a battery monomer, a battery and a power utilization device. The battery monomer (200) comprises a shell (20), an electrode assembly (30) and an adapter (40); a first space (2001) is formed between the end face of the electrode assembly and the side wall of the shell, an electrode terminal (203), a support (205) and a pressure relief mechanism (202) are arranged on a first wall (201) of the shell, a second space (2001) is formed between the pressure relief mechanism and the electrode assembly, and an exhaust channel (2051) is formed in the support; in the first direction, the projection area of the adapter in the exhaust channel is smaller than the area of the cross section of the exhaust channel. Therefore, under the condition of thermal runaway of the battery monomer, the bracket can prevent the end part of the electrode assembly from abutting against the first wall, and the adapter does not block a circulation space between the exhaust channel and the second space, so that the first space is communicated with the second space through the exhaust channel, and the first space is decompressed.

Description

Technical Field

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

[0002] Energy conservation and emission reduction are the key to the sustainable development of the automobile industry. Electric vehicles have become an important part of the sustainable development of the automobile industry due to their advantages in energy conservation and environmental protection. For electric vehicles, battery technology is an important factor in their development.

[0003] An explosion-proof valve is installed on the end cap of the battery cell to exhaust and reduce the pressure of the battery cell in the event of thermal runaway. However, in the later stage of thermal runaway of the battery cell, the gas at the end of the length direction of the battery cell is difficult to be discharged, resulting in the rupture of the battery cell shell. Utility Model Content

[0004] The purpose of the embodiments of the present application is to provide a battery cell, a battery and an electrical device to solve the problem of difficulty in relieving pressure in the side cavity in the later stage of thermal runaway of the battery cell in the related art.

[0005] In a first aspect, an embodiment of the present application provides a battery cell, including:

[0006] shell;

[0007] The electrode assembly is accommodated in the housing, and a first space is formed between an end surface of the electrode assembly in a first direction and a side wall of the housing;

[0008] The housing has a first wall, an electrode terminal is arranged on the first wall, a bracket is arranged at an end of the first wall along a first direction, a pressure relief mechanism is arranged on the first wall, a second space is formed between the pressure relief mechanism and the electrode assembly, an exhaust passage extending along the first direction is opened on the bracket, and the bracket is used to abut against a side of the electrode assembly facing the first wall, so that the exhaust passage connects the first space with the second space;

[0009] The adapter is arranged between the bracket and the pressure relief mechanism and connected between the electrode assembly and the electrode terminal; along the first direction, the projection area of ​​the adapter in the exhaust channel is smaller than the cross-sectional area of ​​the exhaust channel.

[0010] In the technical solution of the embodiment of the present application, a bracket is arranged on the first wall of the outer shell, so that in the event of thermal runaway of the battery cell, the electrode assembly can be blocked from abutting against the first wall, and the exhaust channel in the bracket connects the first space at the end of the outer shell with the second space at the pressure relief mechanism; and the projection area of ​​the adapter along the first direction in the exhaust channel is set to be smaller than the area of ​​the exhaust channel, which can avoid the adapter blocking the flow space between the exhaust channel and the second space to a certain extent, so that the gas in the first space can be discharged to the second space and then discharged from the pressure relief mechanism.

[0011] In some embodiments, the adapter includes a main body portion and a connecting portion that are connected to each other, the main body portion is connected to the electrode assembly, and the connecting portion is connected to the electrode terminal.

[0012] The main body is provided so as to be connected to the electrode assembly, and the connecting portion is provided so as to be connected to the electrode terminal, thereby realizing electrical connection between the electrode terminal and the electrode assembly.

[0013] In some embodiments, the thickness of the side wall of the bracket close to the first wall is T1, the height of the exhaust channel along the thickness direction of the first wall is H1, the height of the connecting portion protruding from the first wall toward the electrode assembly is H2, the thickness of the main body is T2, and T1+H1>T2+H2.

[0014] By making T1+H1>T2+H2, the main body can be away from one side of the first wall and the exhaust channel can be away from the side wall of the first wall, with a spacing distance along the thickness direction of the first wall, so that the gas flowing out of the exhaust channel can flow from the side of the main body close to the electrode assembly to the pressure relief mechanism.

[0015] In some embodiments, a center plane of the bracket along the second direction coincides with a center plane of the connecting portion along the second direction, and the second direction is perpendicular to the first direction.

[0016] Along the second direction, the central plane of the bracket is made to coincide with the central plane of the connecting portion, so that the gas flowing out of the exhaust channel can reach the pressure relief mechanism more quickly, so as to exhaust and relieve the pressure of the first space.

[0017] In some embodiments, the diameter of the connecting portion close to one end of the main body is L, the width of the exhaust channel along the second direction is W, and L <W,T1<H2。

[0018] By setting the diameter L of the connecting part close to one end of the main body to be smaller than the length W of the exhaust channel, and setting the thickness T1 of the side wall of the bracket close to the first wall to be smaller than the height H2 of the connecting part protruding from the first wall, the gas flowing out of the exhaust channel can pass through the area formed between the side of the connecting part close to the first wall and the two sides of the connecting part along the second direction, so as to reduce the obstruction to the gas flowing out of the exhaust channel and further improve the exhaust rate of the first space.

[0019] In some embodiments, L / W ≤ 0.95.

[0020] By setting the diameter L of the connecting part close to one end of the main body to be less than or equal to 0.95 of the length W of the exhaust channel, a larger space can be provided between the side of the main body close to the first wall and the two sides of the connecting part along the second direction for gas circulation, thereby reducing obstruction to gas outflow from the exhaust channel and facilitating the exhaust rate of the first space.

[0021] In some embodiments, a diameter of an end of the connecting portion close to the main body portion is L, a width of the exhaust passage along the second direction is W, and L≥W.

[0022] By setting the diameter L of the connecting part near one end of the main body to be greater than or equal to the length W of the exhaust channel, the volume of the connecting part can be made larger to facilitate connection with the electrode terminal, and the connection strength between the connecting part and the electrode terminal can be improved to reduce the internal resistance of the battery cell.

[0023] In some embodiments, (H2+T2-T1) / H1≤0.5.

[0024] If (H2+T2-T1) / H1≤0.5, the distance from the side of the main body away from the first wall to the side wall of the exhaust channel away from the first wall in the thickness direction of the first wall is greater than or equal to half of the height H1 of the exhaust channel, thereby making the area of ​​the adapter blocking the gas flowing out of the exhaust channel smaller, thereby facilitating the exhaust rate of the first space.

[0025] In some embodiments, H2≤T1.

[0026] If H2≤T1, then along the first direction, the connection portion is located in the area where the side wall of the bracket is close to the first wall, thereby greatly reducing the connection portion's obstruction to gas flowing out of the exhaust channel, so that the gas flowing out of the exhaust channel can reach the second space, thereby facilitating the exhaust rate of the first space.

[0027] In some embodiments, the thickness of the side wall of the bracket close to the first wall is T1, the height of the exhaust channel along the thickness direction of the first wall is H1, the height of the connecting portion protruding from the first wall in the direction of the electrode assembly is H2, the thickness of the main body is T2, the center plane of the bracket along the second direction coincides with the center plane of the connecting portion along the second direction, the diameter of one end of the connecting portion close to the main body is L, the width of the exhaust channel along the second direction is W, and T1+H1≤T2+H2, L <W。

[0028] Since the adapter connects the electrode terminal and the electrode assembly, there will be a certain distance between the electrode assembly and the first wall. Through the above-mentioned structural setting, the connecting part is set to be longer, and the main body is connected to the connecting part, so that the main body can be closer to the electrode assembly, so as to facilitate the connection between the main body and the electrode assembly, and also facilitate the connection between the connecting part and the electrode terminal on the first wall; in addition, in the case of thermal runaway of the battery cell, if the pole piece of the electrode assembly moves toward the first wall and pushes the main body of the adapter, due to the supporting effect of the connecting part, when the main body bends toward the first wall, there will also be a gap space between the opposite sides of the connecting part and the bent main body for gas circulation, so that the gas flowing out of the exhaust channel reaches the second space to exhaust and depressurize the first space.

[0029] In some embodiments, L / W ≤ 0.95.

[0030] Setting the diameter L of the connecting portion close to one end of the main body to be less than or equal to 0.95 of the length W of the exhaust passage can allow the space between the two opposite sides of the connecting portion and the main body to have a larger facing area with the exhaust passage to provide gas circulation, reduce obstruction to gas outflow from the exhaust passage, and facilitate exhaust and pressure relief in the first space.

[0031] In some embodiments, the center plane of the bracket along the second direction is spaced apart from the center plane of the connecting portion along the second direction, along the first direction, the projection area of ​​the bracket partially overlaps with the projection area of ​​the connecting portion, and the second direction is perpendicular to the first direction.

[0032] The center plane of the bracket along the second direction is spaced from the center plane of the connecting part along the second direction, so as to facilitate the layout of the bracket and the installation of the bracket; in the case of thermal runaway of the battery cell, if the pole piece of the electrode assembly moves toward the first wall and pushes the main body of the adapter, due to the supporting effect of the connecting part, when the main body bends toward the first wall, there will be gaps between the opposite sides of the connecting part and the bent main body. In the first direction, the projection area of ​​the bracket is partially overlapped with the projection area of ​​the connecting part, so that the gap space on the side where the connecting part overlaps with the projection area of ​​the bracket can be used for gas circulation, so that the gas flowing out of the exhaust channel reaches the second space to exhaust and depressurize the first space.

[0033] In some embodiments, the diameter of the connecting portion close to one end of the main body is L, the distance between the center plane of the bracket along the second direction and the center plane of the connecting portion along the second direction is D, and D≤L / 2.

[0034] By setting the distance D between the center plane of the bracket along the second direction and the center plane of the connecting part along the second direction to be less than or equal to half of the diameter L of the connecting part close to one end of the main body, the projection area of ​​the bracket along the first direction can overlap with at least half of the connecting part. Therefore, in the case of thermal runaway of the battery cell, if the pole piece of the electrode assembly moves toward the first wall and pushes the main body of the adapter, due to the supporting effect of the connecting part, when the main body bends toward the first wall, there will also be gap space between the opposite sides of the connecting part and the bent main body, so that the gap space on the side where the connecting part overlaps with the projection area of ​​the bracket at least has a larger area in the first direction and faces the exhaust channel, which can reduce the obstruction to the gas flow, and then make it easier for the gas flowing out of the exhaust channel to flow to the second space, so as to exhaust and depressurize the first space.

[0035] In some embodiments, the height of the connecting portion protruding from the first wall toward the electrode assembly is in the range of 0.3 mm to 2 mm.

[0036] Through the above structural design, not only can the adapter block less of the exhaust passage in the first direction, but also the connection between the connecting part and the electrode terminal can be facilitated.

[0037] In some embodiments, the height of the connecting portion protruding from the first wall toward the electrode assembly is in the range of 0.5 mm to 1.5 mm.

[0038] Through the above structural design, the adapter can block less of the exhaust channel in the first direction, and the connecting part and the electrode terminal can be easily connected.

[0039] In some embodiments, the connecting portion and the main body are an integrally formed structure; or, the connecting portion and the electrode terminal are an integrally formed structure.

[0040] The connecting part and the main body are an integrally formed structure, which can facilitate the processing and manufacturing of the adapter and facilitate connection with the electrode terminal.

[0041] The connecting part and the electrode terminal are integrally formed to facilitate the processing and manufacturing of the main body.

[0042] In some embodiments, the stent is a metal stent or a ceramic stent.

[0043] Using a metal bracket or a ceramic bracket can have higher heat resistance and avoid deformation caused by thermal runaway of the battery cell to a certain extent.

[0044] In some embodiments, a notch communicating with the exhaust channel is provided on a side of the bracket facing away from the first wall.

[0045] Providing a notch on the side of the bracket away from the first wall can increase the area for gas circulation, facilitate exhaust, and also facilitate the processing and manufacturing of the bracket.

[0046] In some embodiments, exhaust channels are respectively provided at two ends of the bracket along the second direction.

[0047] The exhaust channels are arranged at both ends of the bracket, so as to better divert the gas flowing out of the exhaust channel, thereby reducing the obstruction of the adapter to the gas and facilitating the gas to flow to the second space.

[0048] In some embodiments, the exhaust passage has a triangular cross-section.

[0049] If the cross section of the exhaust channel is set to be triangular, the side walls surrounding the exhaust channel are also triangular, which can make the structure of the exhaust channel more stable and facilitate gas circulation.

[0050] In some embodiments, a support rib is disposed in the exhaust channel, and the support rib is extended along the first direction.

[0051] Support ribs are provided in the exhaust passage to increase the structural strength of the bracket to reduce the risk of deformation due to extrusion of the electrode assembly.

[0052] In some embodiments, a plastic part is provided on the first wall, and the plastic part is installed on a side of the first wall close to the bracket. A through hole is provided on the plastic part, and the adapter is connected to the electrode terminal through the through hole. The plastic part has a groove for the bracket to be placed.

[0053] A plastic part is provided to insulate the first wall from the electrode assembly; a groove is provided on the plastic part, and the bracket is placed in the groove to protect the bracket.

[0054] In some embodiments, the plastic part is provided with a boss in a direction away from the first wall, and the groove is provided on a side of the boss close to the first wall.

[0055] Providing a boss on the plastic part can limit the distance between the electrode assembly and the first wall, so as to reserve storage space for the tabs on the electrode assembly to reduce the risk of damaging the tabs; and providing a groove on the boss facilitates manufacturing, improves integration, and reduces the material used in the plastic part.

[0056] In a second aspect, an embodiment of the present application provides a battery, comprising a battery cell as described in the above embodiment.

[0057] In a third aspect, an embodiment of the present application provides an electrical device, comprising a battery as described in the above embodiment.

[0058] The above description is only an overview of the technical solution of the present application. In order to more clearly understand the technical means of the present application, it can be implemented in accordance with the contents of the specification. In order to make the above and other purposes, features and advantages of the present application more obvious and easy to understand, the specific implementation methods of the present application are listed below. BRIEF DESCRIPTION OF THE DRAWINGS

[0059] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the drawings required for use in the embodiments or exemplary technical descriptions 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 these drawings without paying creative work.

[0060] Figure 1 A schematic diagram of the structure of a vehicle according to some embodiments of the present application;

[0061] Figure 2 A schematic diagram of the exploded structure of a battery according to some embodiments of the present application;

[0062] Figure 3 A schematic diagram of the exploded structure of a battery cell according to some embodiments of the present application;

[0063] Figure 4 A schematic cross-sectional view of a battery cell according to some embodiments of the present application;

[0064] Figure 5 This is a schematic diagram of the exploded structure of the end cap of some embodiments of the present application;

[0065] Figure 6 for Figure 5 A schematic diagram of the structure of the middle cover plate, bracket and adapter assembly;

[0066] Figure 7 for Figure 6 A bottom view of the structure of the middle cover plate, bracket and adapter assembly;

[0067] Figure 8 For along Figure 7 Schematic diagram of the cross-sectional structure along the AA line;

[0068] Fig. 9 for Figure 8 An enlarged view of one end of the end cap;

[0069] Fig.10 A schematic diagram of a first positional relationship among a first wall, a bracket and an adapter in a battery cell provided in some embodiments of the present application;

[0070] Fig.11 for Fig.10 A schematic diagram of the positional relationship between the first wall, the bracket and the adapter after the main body of the electrode assembly abuts against the adapter is bent in the case of thermal runaway of the battery cell shown;

[0071] Fig.12 A schematic diagram of a second positional relationship among a first wall, a bracket and an adapter provided in some embodiments of the present application;

[0072] Fig.13 A schematic diagram of a third positional relationship among a first wall, a bracket and an adapter provided in some embodiments of the present application;

[0073] Fig.14 A schematic diagram of a fourth positional relationship among a first wall, a bracket and an adapter provided in some embodiments of the present application;

[0074] Fig.15 Schematic diagram of the combined structure of the first wall, the electrode terminal and the adapter in some other embodiments of the present application;

[0075] Fig.16 A schematic diagram of the structure of a bracket provided in some embodiments of the present application;

[0076] Fig.17 A schematic diagram of the structure of a bracket provided in some other embodiments of the present application;

[0077] Fig.18 A schematic diagram of the structure of a bracket provided in some other embodiments of the present application;

[0078] Fig.19 A schematic diagram of the structure of a bracket provided in some other embodiments of the present application;

[0079] Fig. 20 A schematic diagram of the structure of a bracket provided in some other embodiments of the present application;

[0080] Fig.21 A bottom-up structural schematic diagram of a cover plate, a bracket and an adapter assembly provided in other embodiments of the present application.

[0081] Among them, the main marks of the drawings in the figure are:

[0082] 1000-vehicle; 1001-battery; 1002-controller; 1003-motor;

[0083] 100-box; 101-first part; 102-second part;

[0084] 200-battery cell; 2001-first space; 2002-second space; 20-housing; 201-first wall; 21-end cover; 211-cover plate; 202-pressure relief mechanism; 203-electrode terminal; 204-plastic part; 2041-through hole; 2042-boss; 2043-groove; 205-bracket; 2051-channel; 2052-notch; 2053-support rib; 22-housing;

[0085] 30 - electrode assembly; 31 - pole ear; 40 - adapter; 401 - gap space; 41 - main body; 42 - connecting part; M1 - center plane of the bracket along the second direction; M2 - center plane of the connecting part along the second direction. DETAILED DESCRIPTION

[0086] In order to make the technical problems, technical solutions and beneficial effects to be solved by the present application more clearly understood, the present application is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present application and are not used to limit the present application.

[0087] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by technicians in the technical field to which this application belongs; the terms used herein are only for the purpose of describing specific embodiments and are not intended to limit this application; the terms "including" and "having" in the specification and claims of this application and the above-mentioned figure descriptions and any variations thereof are intended to cover non-exclusive inclusions.

[0088] In the description of the embodiments of the present application, the technical terms "first", "second", etc. are only used to distinguish different objects, and cannot be understood as indicating or implying relative importance or implicitly indicating the number, specific order or primary and secondary relationship of the indicated technical features. Therefore, the features defined as "first" or "second" may explicitly or implicitly include one or more of the features.

[0089] Reference to "embodiments" herein 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 herein may be combined with other embodiments in any suitable manner.

[0090] In the description of the embodiments of the present application, the term "and / or" is only a description of the association relationship of the associated objects, indicating that there may 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 article generally indicates that the associated objects before and after are in an "or" relationship.

[0091] In the description of the embodiments of the present application, the term "multiple" refers to more than two (including two), and similarly, "multiple groups" refers to more than two groups (including two groups), and "multiple pieces" refers to more than two pieces (including two pieces). "Several" means one or more than one, unless otherwise clearly and specifically defined.

[0092] In the description of the embodiments of the present application, the orientations or positional relationships indicated by technical terms such as "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise", "axial", "radial", and "circumferential" are based on the orientations or positional relationships shown in the accompanying drawings and are only for the convenience of describing the embodiments of the present application and simplifying the description, and do not indicate or imply that the referred device or element must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the embodiments of the present application.

[0093] In the description of the embodiments of the present application, unless otherwise clearly specified and limited, technical terms such as "installed", "connected", "connected", "fixed" and the like should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, and it can be the internal connection of two elements or the interaction relationship between two elements. For ordinary technicians in this field, the specific meanings of the above terms in the embodiments of the present application can be understood according to the specific circumstances.

[0094] In the description of the embodiments of the present application, unless otherwise clearly specified and limited, when an element is referred to as being "fixed to" or "disposed on" another element, it may be directly on the other element or indirectly on the other element. When an element is referred to as being "connected to" another element, it may be directly connected to the other element or indirectly connected to the other element.

[0095] The battery cells in the embodiments of the present application include but are not limited to lithium-ion secondary battery cells, lithium-ion primary battery cells, lithium-sulfur battery cells, sodium-lithium-ion battery cells, sodium-ion battery cells or magnesium-ion battery cells. The shape of the battery cell includes but is not limited to a cylinder, a flat body, a rectangular parallelepiped or other shapes. The battery cell is generally divided into cylindrical battery cells, square battery cells and soft-pack battery cells according to the packaging method, including but not limited to: cylindrical battery cells, square battery cells and soft-pack battery cells.

[0096] The battery mentioned in the embodiments of the present application refers to a single physical module including one or more battery cells to provide higher voltage and capacity. For example, the battery mentioned in the present application may include a battery module or a battery pack, etc. The battery generally includes a casing for encapsulating one or more battery cells. The casing can prevent liquid or other foreign matter from affecting the charging or discharging of the battery cells to a certain extent. In some cases, the battery cells can also be used directly, that is, the battery may not include a casing, which is not limited here.

[0097] In a battery, when there are multiple battery cells, the multiple battery cells can be connected in series, in parallel, or in a mixed connection. A mixed connection means that the multiple battery cells are connected in series and in parallel. Multiple battery cells can be directly connected in series, in parallel, or in a mixed connection, and then the whole formed by the multiple battery cells is accommodated in a box; of course, the battery can also be a battery module formed by connecting multiple battery cells in series, in parallel, or in a mixed connection, and then the multiple battery modules are connected in series, in parallel, or in a mixed connection to form a whole, and accommodated in a box. The battery can also include other structures. For example, the battery can also include a busbar component for realizing electrical connection between multiple battery cells.

[0098] The battery cell in the embodiment of the present application includes an electrode assembly, a shell and an end cover. The electrode assembly is installed in the shell, and the end cover is covered on the shell to form an outer shell 20 of the battery cell to protect the electrode assembly.

[0099] The electrode assembly, also known as the battery cell, is a component that stores and releases electrical energy. The electrode assembly consists of a positive electrode sheet, a negative electrode sheet, and a separator. The electrode assembly mainly relies on the movement of metal ions between the positive electrode sheet and the negative electrode sheet to work. The positive electrode sheet includes a positive electrode collector and a positive electrode active material layer. The positive electrode active material layer is coated on the surface of the positive electrode collector. The portion of the positive electrode collector that is not coated with the positive electrode active material layer protrudes from the portion that is coated with the positive electrode active material layer. The portion that is not coated with the positive electrode active material layer serves as a positive electrode tab, or a metal conductor is welded on the positive electrode collector and led out to serve as a positive electrode tab. Taking lithium-ion batteries as an example, the material of the positive electrode collector can be aluminum, and the positive electrode active material can be lithium cobalt oxide, lithium iron phosphate, ternary lithium, or lithium manganese oxide, etc. The negative electrode sheet includes a negative electrode current collector and a negative electrode active material layer. The negative electrode active material layer is coated on the surface of the negative electrode current collector. The portion of the negative electrode current collector that is not coated with the negative electrode active material layer protrudes from the portion that is coated with the negative electrode active material layer. The portion that is not coated with the negative electrode active material layer serves as a negative electrode tab, or a metal conductor is welded and led out on the negative electrode current collector to serve as a negative electrode tab. The material of the negative electrode current collector may be copper, and the negative electrode active material may be carbon or silicon, etc. In order to ensure that a large current is passed without melting to a certain extent, the number of positive electrode tabs is multiple and stacked together, and the number of negative electrode tabs is multiple and stacked together. It can be understood that in the electrode assembly, the number of positive electrode tabs may be one, and the number of negative electrode tabs may also be one. That is, two groups of tabs are provided on the electrode assembly, each group includes at least one tab, and one group of tabs is a positive electrode tab, and the other group of tabs is a negative electrode tab.

[0100] The electrode assembly can be a wound structure or a laminated structure. The embodiments of the present application are not limited to this. The wound structure is mostly to weld the pole ear to the current collector, and then arrange it in the order of positive electrode sheet-diaphragm-negative electrode sheet-diaphragm; and then wind it to form a cylindrical or square battery cell. The laminated structure is mostly to lead the pole ear on the current collector, arrange the positive electrode sheet, negative electrode sheet and diaphragm in the order of positive electrode sheet-diaphragm-negative electrode sheet-diaphragm, and stack them layer by layer to form a laminated battery cell; wherein, the diaphragm can be cut and directly laminated with the diaphragm sheet, or the diaphragm is not cut, but laminated in Z-shaped folding. The material of the diaphragm can be PP (Polypropylene, polypropylene) or PE (Polyethylene, polyethylene), etc. The diaphragm is an insulating film arranged between the positive electrode sheet and the negative electrode sheet. Its main function is to isolate the positive and negative electrodes and prevent the electrons in the battery from passing freely to prevent short circuits, and allow the ions in the electrolyte to pass freely between the positive and negative electrodes to form a loop between the positive and negative electrodes. The positive electrode sheet and the negative electrode sheet are collectively referred to as the electrode sheet. The positive electrode tab and the negative electrode tab are collectively referred to as the tab.

[0101] After the electrode assembly is manufactured, it will be installed in the shell and injected with electrolyte so that the electrode assembly is immersed in the electrolyte and can fully absorb the electrolyte. The electrolyte can provide some active ions, which are used as conductive ions during the charging and discharging process; in addition, the electrolyte also provides ion channels, or carriers, so that ions can move freely in it to achieve electrical conduction between the electrodes.

[0102] The end caps of the battery cells are provided with electrode terminals. Electrode terminals refer to conductive parts provided on the end caps. Electrode terminals are connected to the tabs of the electrode assembly to output the electric energy of the battery cell or charge the battery cell. A battery cell generally has two electrode terminals, which are respectively connected to the positive and negative tabs of the electrode assembly. The electrode terminal connected to the positive tab is the positive electrode terminal, and the electrode terminal connected to the negative tab is the negative electrode terminal. The electrode assembly is connected to the electrode terminals to form a battery cell.

[0103] In order to facilitate the connection between the pole lug and the electrode terminal, an adapter plate is provided in the battery cell. Generally, there are two adapter plates, which correspond to two electrode terminals respectively. Each adapter plate is connected to the corresponding electrode terminal, and each adapter plate is connected to the corresponding pole lug. In other words, each pole lug is connected to the corresponding electrode terminal through the adapter plate to facilitate the connection between the pole lug and the electrode terminal, and the connection is more stable.

[0104] When a battery cell is charged, the current converts electrical energy into chemical energy through the chemical reaction between the electrolyte and the electrode and stores it in the battery cell. During the discharge process, chemical energy is converted into electrical energy and released. This energy conversion process is accompanied by energy loss and heat generation. If the heat dissipation inside the battery cell is poor and the heat cannot be effectively dissipated, the battery cell will overheat. There is a certain internal resistance inside the battery cell. When the current passes through the internal resistance, resistance loss will be generated, causing the internal heat of the battery cell. When the current is too large or the internal resistance is too high, the heat inside the battery cell will increase, causing the battery cell to overheat. If the battery cell exceeds its designed maximum voltage during charging, or the battery cell voltage drops too low during discharge, it will cause the battery cell to overvoltage or overdischarge. Overcharging or overdischarging will cause the chemical reaction inside the battery cell to run away, generate too much heat, and cause the battery cell to overheat. In addition, there may be defects in the design or manufacturing process of the battery cell, such as improper material selection, poor assembly of the battery cell, etc. These defects may lead to poor heat dissipation inside the battery cell or uneven current distribution, thereby increasing the risk of overheating of the battery cell. Therefore, the battery cell may overheat and run away during charging or use.

[0105] A certain amount of gas is usually contained inside the battery cell. When the battery cell is charged or discharged, the solution in the electrolyte will produce or absorb gas. The generation of these gases will cause the gas pressure inside the battery cell to increase, which will cause the battery cell to swell and deform. During the charging or discharging process of the battery cell, the positive and negative electrode materials will undergo chemical reactions to form new compounds. These chemical reactions are accompanied by changes in volume, which cause the volume changes of the internal materials of the battery cell, causing the battery to swell and deform. When the battery cell is overcharged or over-discharged, the internal chemical reaction of the battery cell will be out of control, excessive gas will be generated, or the structure of the electrode material will be damaged, which will cause the battery cell to swell and deform. Charging or discharging the battery cell in a high temperature environment will accelerate the internal chemical reaction, increase the generation of gas and the change in volume. High temperature will also cause the expansion of the internal material of the battery cell, which will also cause the battery cell to swell and deform. Therefore, pressure relief mechanisms such as explosion-proof valves and explosion-proof plates will also be set on the end cover to release the internal pressure when the internal pressure or temperature of the battery cell reaches a threshold.

[0106] The electrode assembly is placed in the shell, and there must be a certain gap between the end face in the length direction and the shell to form a side cavity. In order to allow the gas in the shell to be discharged from the pressure relief mechanism. When the electrode assembly is in thermal runaway, the generated gas will impact the electrode piece of the electrode assembly, causing the electrode piece to move toward the end cover and abut against the end cover, which will block the channel between the side cavity and the pressure relief mechanism, making it difficult to exhaust the gas in the side cavity, or untimely exhaust, resulting in the side of the battery cell shell 20 rupture, so that the high-temperature metal particles in the battery cell will erupt to the adjacent battery cell, causing heat spread.

[0107] Based on the above considerations, in order to solve the problem that the gas in the side cavity is difficult to reach the pressure relief mechanism for discharge in the later stage of thermal runaway of the battery cell, an embodiment of the present application provides a battery cell. By setting a bracket on the first wall 201 of the outer shell 20, in the case of thermal runaway of the battery cell, the electrode assembly can be blocked from abutting against the first wall 201, and the exhaust channel in the bracket connects the first space at the end of the outer shell 20 and the second space at the pressure relief mechanism; and the projection area of ​​the adapter in the exhaust channel along the first direction is set to be smaller than the area of ​​the exhaust channel, which can avoid the adapter blocking the flow space between the exhaust channel and the second space to a certain extent, so that the gas in the first space is discharged to the second space and then discharged from the pressure relief mechanism, thereby improving the gas discharge rate of the first space, and to a certain extent avoiding the problem of side rupture of the outer shell 20 of the battery cell due to untimely discharge of the gas in the first space.

[0108] The battery cells disclosed in the embodiments of the present application can be used in electrical devices that use batteries as power sources or various energy storage systems that use batteries as energy storage elements, such as energy storage power supply systems such as hydropower, thermal power, wind power and solar power stations. Electrical devices can be, but are not limited to, mobile phones, tablets, laptops, electric toys, electric tools, electric bicycles, electric motorcycles, electric cars, ships, spacecraft, and the like. Among them, electric toys can include fixed or mobile electric toys, such as game consoles, electric car toys, electric ship toys, and electric airplane toys, and the like, and spacecraft can include airplanes, rockets, space shuttles, and spacecraft, and the like.

[0109] For the convenience of description, an electric device is provided in accordance with an embodiment of the present application, and the electric device is described by taking a vehicle as an example.

[0110] Please refer to Figure 1 , Figure 1 A schematic diagram of the structure of a vehicle 1000 provided for some embodiments of the present application. The vehicle 1000 may be a fuel vehicle, a gas vehicle or a new energy vehicle, and the new energy vehicle may be a pure electric vehicle, a hybrid vehicle or an extended-range vehicle, etc. A battery 1001 is provided inside the vehicle 1000, and the battery 1001 may be provided at the bottom, head or tail of the vehicle 1000. The battery 1001 may be used to power the vehicle 1000, for example, the battery 1001 may be used as an operating power source for the vehicle 1000. The vehicle 1000 may also include a controller 1002 and a motor 1003, and the controller 1002 is used to control the battery 1001 to power the motor 1003, for example, for the starting, navigation and working power requirements of the vehicle 1000 during driving.

[0111] In some embodiments of the present application, the battery 1001 can not only serve as the operating power source of the vehicle 1000, but also serve as the driving power source of the vehicle 1000, replacing or partially replacing fuel or natural gas to provide driving power for the vehicle 1000.

[0112] Please refer to Figure 2 , Figure 2 Schematic diagram of the exploded structure of the battery 1001 provided for some embodiments of the present application. The battery 1001 includes a box 100 and a battery cell 200, and the battery cell 200 is contained in the box 100. Among them, the box 100 is used to provide a storage space for the battery cell 200, and the box 100 can adopt a variety of structures. In some embodiments, the box 100 may include a first part 101 and a second part 102, and the first part 101 and the second part 102 cover each other, and the first part 101 and the second part 102 jointly define a storage space for accommodating the battery cell 200. The second part 102 can be a hollow structure with one end open, and the first part 101 can be a plate-like structure, and the first part 101 covers the open side of the second part 102, so that the first part 101 and the second part 102 jointly define a storage space; the first part 101 and the second part 102 can also be hollow structures with one side open, and the open side of the first part 101 covers the open side of the second part 102. Of course, the box 100 formed by the first part 101 and the second part 102 can be in various shapes, such as a cylinder, a cuboid, etc. After multiple battery cells 200 are connected in parallel, in series, or in mixed series, they are placed in the box 100 formed by the first part 101 and the second part 102 being buckled together.

[0113] See also Figures 3 to 5 , Figure 3 A schematic diagram of the exploded structure of a battery cell 200 provided in some embodiments of the present application. Figure 4 This is a schematic cross-sectional structural diagram of a battery cell 200 provided in some embodiments of the present application. Figure 5 Schematic diagram of the exploded structure of the end cover 21 of the battery cell 200 provided in some embodiments of the present application. Figures 3 to 5 In the figure, the X-axis direction is the length direction of the battery cell 200, the Y-axis direction is the width direction of the battery cell 200, and the Z-axis direction is the height direction of the battery cell 200. In addition, the X-axis direction is also the length direction of the shell 22, the Y-axis direction is also the width direction of the shell 22, and the Z-axis direction is also the height direction of the shell 22. The X-axis direction is also the length direction of the end cap 21, the Y-axis direction is also the width direction of the end cap 21, and the Z-axis direction is also the thickness direction of the end cap 21. In addition, the X-axis direction is also the length direction of the electrode assembly 30, the Y-axis direction is also the width direction of the electrode assembly 30, and the Z-axis direction is also the height direction of the electrode assembly 30.

[0114] See also Figures 3 to 14 According to some embodiments of the present application, the present application provides a battery cell 200, including a housing 20, an electrode assembly 30 and an adapter 40; the electrode assembly 30 is accommodated in the housing 20, and a first space 2001 is formed between the end surface of the electrode assembly 30 in the first direction P and the side wall of the housing 20. The housing 20 has a first wall 201, and the first wall 201 is provided with an electrode terminal 203, a bracket 205 and a pressure relief mechanism 202. A second space 2002 is formed between the pressure relief mechanism 202 and the electrode assembly 30, the bracket 205 is provided at the end of the first wall 201 along the first direction P, and the bracket 205 is provided with an exhaust channel 2051 extending along the first direction P, and the bracket 205 is used to abut against the side of the electrode assembly 30 facing the first wall 201, so that the exhaust channel 2051 connects the first space 2001 with the second space 2002. The adapter 40 is disposed between the bracket 205 and the pressure relief mechanism 202 and connected between the electrode assembly 30 and the electrode terminal 203 . Along the first direction P, the projection area of ​​the adapter 40 in the exhaust channel 2051 is smaller than the cross-sectional area of ​​the exhaust channel 2051 .

[0115] The shell 20 refers to a shell having an internal space to accommodate the electrode assembly 30, the electrolyte and other components. The shell 20 can be in various shapes and sizes, such as a rectangular parallelepiped, a cylindrical shape, a hexagonal prism shape, etc. Specifically, the shape of the shell 20 can be determined according to the specific shape and size of the battery cell 200. The shell 20 can be made of various materials, such as copper, iron, aluminum, stainless steel, aluminum alloy, plastic, etc., and the embodiments of the present application do not impose any special restrictions on this.

[0116] Generally speaking, the housing 20 includes a shell 22 and an end cap 21, and the end cap 21 is covered on the shell 22. The shell 22 refers to an internal space for accommodating the electrode assembly 30, the electrolyte and other components. An opening is provided on the shell 22 to install the electrode assembly 30. The shell 22 can be of various shapes and sizes, such as a rectangular parallelepiped, a cylindrical shape, a hexagonal prism shape, etc. Specifically, the shape of the shell 22 can be determined according to the specific shape and size of the battery cell 200. The material of the shell 22 can be various, such as copper, iron, aluminum, stainless steel, aluminum alloy, plastic, etc., and the embodiments of the present application do not impose any special restrictions on this.

[0117] The end cap 21 refers to a component that covers the opening of the housing 22 to isolate the internal environment of the battery cell 200 from the external environment. The housing 22 and the end cap 21 cooperate to form an internal environment of the battery cell 200, wherein the formed internal environment can be used to accommodate the electrode assembly 30, electrolyte and other components. The housing 22 and the end cap 21 can be independent components, and an opening can be set on the housing 22, and the internal environment of the battery cell 200 is formed by covering the opening with the end cap 21.

[0118] The end cap 21 includes a cover sheet 211, which is a plate or sheet-like member forming the main structure of the end cap 21. The cover sheet 211 covers the opening of the shell 22 to isolate the internal environment of the battery cell 200 from the external environment. The shape of the cover sheet 211 can be adapted to the shape of the shell 22 to fit on the shell 22. Optionally, the cover sheet 211 can be made of a material with a certain hardness and strength (such as aluminum alloy), so that the cover sheet 211 is not easily deformed when squeezed and collided, so that the battery cell 200 can have a higher structural strength and the reliability performance can also be improved.

[0119] The housing 20 has a first wall 201, which is a side wall of the housing 20, such as an end cover 21. When the end cover 21 includes a cover sheet 211, the first wall 201 may be the cover sheet 211. Of course, the first wall 201 may also be a wall surface of the housing 22, such as a bottom plate or a side plate of the housing 22.

[0120] Two mutually perpendicular directions are defined, namely, a first direction P and a second direction Q, and the first direction P and the second direction Q are both perpendicular to the thickness direction K of the first wall 201. When the first wall 201 is the cover sheet 211, or the first wall 201 is the side wall of the shell 22 away from the cover sheet 211, the first direction P may be along the length direction X of the battery cell, and the second direction Q is along the width direction Y of the battery cell; of course, the first direction P may also be inclined to the length direction X of the battery cell, and the second direction Q will also be inclined to the width direction Y of the battery cell. When the first wall 201 is the side wall of the end of the length direction X of the shell, the first direction P may be along the height direction Z of the battery cell, and the second direction Q is along the width direction Y of the battery cell; of course, the first direction P may also be inclined to the height direction Z of the battery cell, and the second direction Q will also be inclined to the width direction Y of the battery cell. When the first wall 201 is the side wall of the end of the width direction Y of the shell, the first direction P can be along the length direction X of the battery cell, and the second direction Q can be along the height direction Z of the battery cell; of course, the first direction P can also be inclined to the length direction X of the battery cell, and the second direction Q will also be inclined to the height direction Z of the battery cell. The electrode terminal 203 refers to a conductive member on the battery cell 200, which is connected to the pole ear 31 of the electrode assembly 30 to output the electric energy of the battery cell 200 or charge the battery cell 200. The electrode terminal 203 is provided on the first wall 201, and the electrode terminal 203 is supported by the first wall 201. When the first wall 201 is a cover sheet 211, the electrode terminal 203 is provided on the cover sheet 211.

[0121] The pressure relief mechanism 202 is a structure for releasing the internal pressure when the internal pressure or temperature of the battery cell 200 reaches a threshold. The pressure relief mechanism 202 is arranged on the first wall 201 to support the pressure relief mechanism 202 through the first wall 201. The pressure relief mechanism 202 can be an explosion-proof valve, an explosion-proof plate, etc. arranged on the first wall 201.

[0122] See also Figure 4 The electrode assembly 30 is a component for storing and releasing electric energy. The electrode assembly 30 is generally formed by winding or stacking a pole piece and a diaphragm. The electrode assembly 30 is placed in the housing 20, and the housing 20 is used to accommodate the electrode assembly 30. There is a gap between the electrode assembly 30 and the first wall 201 to accommodate the pole ear 31 of the electrode assembly 30, and the portion between the electrode assembly 30 and the pressure relief mechanism 202 forms a second space 2002.

[0123] When the first wall 201 is a cover sheet 211, the electrode assembly 30 is placed in the shell 22, the cover sheet 211 covers the shell 22, and there is a gap between the electrode assembly 30 and the cover sheet 211 to accommodate the electrode tab 31 of the electrode assembly 30. In order to facilitate the installation of the electrode assembly 30 in the shell 22, and the electrode assembly 30 will expand to a certain extent during charging and discharging, and in order to facilitate the filling of electrolyte into the shell 22 and make the electrode assembly 30 absorb the electrolyte, the electrode assembly 30 will be immersed in the electrolyte. Therefore, the size of the electrode assembly 30 will be set smaller than the size of the shell 22, so that after the electrode assembly 30 is installed in the shell 22, there will be a gap between the end face of the electrode assembly 30 and the side wall of the shell 22, and the gap space is the first space 2001, especially the end face of the electrode assembly 30 along the first direction P and the side wall of the shell 20 will form the first space 2001.

[0124] The adapter 40 is a conductive member that connects the electrode assembly 30 and the electrode terminal 203 to electrically connect the electrode assembly 30 and the electrode terminal 203. Specifically, the electrode assembly 30 is provided with a tab 31, and the adapter 40 connects the tab 31 and the corresponding electrode terminal 203 to electrically connect the electrode assembly 30 and the electrode terminal 203.

[0125] See also Figure 4 , Figure 8 and Fig. 9In the case of thermal runaway of the battery cell 200, the electrode assembly 30 will generate gas containing a large amount of metal particles, and the gas at the end of the electrode assembly 30 along the first direction P will flow to the first space 2001, and the gas in the second space 2002 will be discharged from the pressure relief mechanism 202. When the passage between the first space 2001 and the second space 2002 is unobstructed, the gas in the first space 2001 will also flow to the second space 2002 and then be discharged from the pressure relief mechanism 202, which can reduce the risk of the discharged gas spreading to the adjacent battery cells 200. However, in the event of thermal runaway of the battery cell 200, the generated gas will be discharged toward the pressure relief mechanism 202, thereby forming a pressure difference and impact in the outer casing 20. Under the impact of these gases, the electrode assembly 30 will move toward the first wall 201 as a whole, and push the pole ear 31 against the adapter 40. Due to the pushing action of the adapter 40 and the pole ear 31, the portion of the electrode assembly 30 between the two adapters 40 generally will not completely abut the first wall 201, and a certain second space 2002 will still exist at the pressure relief mechanism 202, so that the pressure relief mechanism 202 can discharge the gas in the second space 2002. In addition, since the electrode assembly 30 is made by winding or stacking pole sheets, in the event of thermal runaway of the battery cell 200, the generated gas will also impact the pole sheets, causing the pole sheets to become loose and misaligned, which causes the electrode assembly 30 to be in the middle area of ​​the first direction P, such as the area corresponding to the pressure relief mechanism 202 and the adapter 40. In these areas, some pole sheets will be farther in height from the first wall 201, thereby forming a gas flow channel so that the gas generated by thermal runaway can be discharged from the pressure relief mechanism 202.

[0126] The portion of the electrode assembly 30 at the end of the first direction P is more likely to move up and against the first wall 201, thereby blocking the passage between the first space 2001 and the second space 2002. For example, in a wound electrode assembly 30, the portion of its electrode at the end of the length direction X is bent, and when it moves up and against the first wall 201, it will block the passage between the first space 2001 and the second space 2002; in a stacked electrode assembly 30, the portion of its electrode at the end of the length direction X will have lower strength, and when it moves up and against the first wall 201, it will deform, thereby blocking the passage between the first space 2001 and the second space 2002. When the passage between the first space 2001 and the second space 2002 is blocked, the gas in the first space 2001 will be affected from being discharged through the second space 2002 to the pressure relief mechanism 202. When the air pressure in the first space 2001 is too high, the side wall of the outer shell 20 of the battery cell 200, such as the side wall of the outer shell 20 or the connection between the first wall 201 and the adjacent side wall, will rupture, and the gas in the first space 2001 will be ejected from the rupture, causing heat to spread to the adjacent battery cell 200.

[0127] The exhaust channel 2051 refers to a hole structure provided on the support 205. The exhaust channel 2051 extends along the first direction P and is provided in the support 205, so the gas also flows along the first direction P in the exhaust channel 2051.

[0128] The support 205 is disposed on the first wall 201 to support the support 205 through the first wall 201. The support 205 means that when the battery cell 200 is in thermal runaway and the electrode assembly 30 impacts the first wall 201 due to the pressure of the generated gas and metal particles, the support 205 abuts against the electrode assembly 30, so that the portion of the electrode sheet of the electrode assembly 30 corresponding to the support 205 will not abut against the first wall 201, and the exhaust channel 2051 in the support 205 becomes a bridge connecting the first space 2001 and the second space 2002, that is, the exhaust channel 2051 connects the first space 2001 and the second space 2002, so that the gas and metal particles in the first space 2001 can flow to the second space 2002 and be discharged from the pressure relief mechanism 202 to reduce the pressure of the first space 2001, thereby reducing the risk of the shell 20 of the battery cell 200 being broken.

[0129] Since the adapter 40 connects the electrode lug 31 of the electrode assembly 30 and the electrode terminal 203, and the adapter 40 is located between the pressure relief mechanism 202 and the bracket 205, the gas in the first space 2001 may be blocked by the adapter 40 after flowing out through the exhaust channel 2051 of the bracket 205, thereby affecting the gas flow to the second space 2002 for discharge. If the gas is not discharged in time, it may also cause the pressure in the first space 2001 to increase and damage the outer shell 20 of the battery cell 200.

[0130] The projection area of ​​the adapter 40 in the exhaust channel 2051 refers to the area of ​​the projection of the adapter 40 along the first direction P in the exhaust channel 2051. The cross section of the exhaust channel 2051 refers to the cross section perpendicular to the extension direction of the exhaust channel 2051, and also refers to the cross section perpendicular to the first direction P.

[0131] See also Figure 4 , Figure 8 and Fig. 9 , along the first direction P, the projection area of ​​the adapter 40 in the exhaust channel 2051 is smaller than the cross-sectional area of ​​the exhaust channel 2051, so that in the first direction P, the adapter 40 will not completely block the exhaust channel 2051, reducing the obstruction of the adapter 40 to the gas flowing out of the exhaust channel 2051, so that the gas flowing out of the exhaust channel 2051 can flow from the unblocked area of ​​the adapter 40 to the second space 2002, and be discharged from the pressure relief mechanism 202, thereby achieving pressure relief in the first space 2001, thereby reducing the risk of rupture of the battery cell 200 housing 20 due to excessive pressure in the first space 2001.

[0132] In the technical solution of the embodiment of the present application, a bracket 205 is arranged on the first wall 201 of the outer shell 20, so that in the case of thermal runaway of the battery cell 200, the electrode assembly 30 can be blocked from abutting against the first wall 201, and the exhaust channel 2051 in the bracket 205 connects the first space 2001 at the end of the outer shell 20 and the second space 2002 at the pressure relief mechanism 202; and the projection area of ​​the adapter 40 in the exhaust channel 2051 along the first direction P is set to be smaller than the area of ​​the exhaust channel 2051, which can avoid the adapter 40 from blocking the flow space between the exhaust channel 2051 and the second space 2002 to a certain extent, so that the gas in the first space 2001 can be discharged to the second space 2002 and then discharged from the pressure relief mechanism 202.

[0133] In some embodiments, the bracket 205 is a metal bracket or a ceramic bracket.

[0134] By using a metal bracket or a ceramic bracket, when the battery cell 200 is in thermal runaway, the bracket 205 still has a certain structural strength and will not melt or deform due to thermal runaway of the battery cell 200, so that the bracket 205 can well support the electrode assembly 30. Of course, the bracket 205 can also be made of other high temperature resistant materials.

[0135] Using a metal bracket or a ceramic bracket can have higher heat resistance and avoid deformation of the battery cell 200 due to thermal runaway to a certain extent.

[0136] See also Figure 5 In some embodiments, a plastic part 204 is provided on the first wall 201, and the plastic part 204 is installed on a side of the first wall 201 close to the bracket 205. A through hole 2041 is provided on the plastic part 204, and the adapter 40 is connected to the electrode terminal 203 through the through hole 2041. The plastic part 204 is provided with a groove 2043 for the bracket 205 to be placed.

[0137] The plastic part 204 refers to an insulating part provided on a side of the first wall 201 close to the electrode assembly 30. The plastic part 204 is provided on the first wall 201 to play an insulating protection role, reducing the risk of short circuit caused by contact between the first wall 201 and the electrode assembly 30. In addition, the plastic part 204 is provided on the first wall 201. In the process of installing the first wall 201 on the shell 22, the plastic part 204 can be placed in the shell 22, and the first wall 201 can be positioned by the plastic part 204 so that the first wall 201 and the shell 22 can be welded or bonded.

[0138] The through hole 2041 refers to a hole structure that penetrates the plastic part 204. The through hole 2041 is provided on the plastic part 204 so that the adapter 40 can pass through the through hole 2041 to connect the electrode terminal 203 and the electrode assembly 30.

[0139] The groove 2043 refers to a groove structure provided on the plastic part 204. The groove 2043 is located at a position on the plastic part 204 corresponding to the bracket 205, so that when the plastic part is installed on the first wall 201, the bracket 205 can be placed in the groove 2043, which not only protects the bracket 205. In addition, when the bracket 205 is directly exposed, when the battery cell 200 vibrates, the bracket 205 may collide and scratch the electrode assembly 30, especially when a metal bracket is used, it may also cause a short circuit in the electrode assembly 30. Therefore, the groove 2043 is provided on the plastic part 204 to place the bracket 205 in the groove 2043, so that the bracket 205 can be separated from the electrode assembly 30 to reduce the risk of the bracket 205 being exposed and damaging the electrode assembly 30. Moreover, when a plastic part is used, the plastic part 204 can be melted in the later stage of thermal runaway of the battery cell 200 to reduce the blocking effect of the plastic part 204, so that the gas in the housing 20 is discharged from the pressure relief mechanism 202.

[0140] The plastic part 204 is provided to insulate the first wall 201 from the electrode assembly 30 . A groove 2043 is provided on the plastic part 204 , and the bracket 205 is placed in the groove 2043 to protect the bracket 205 .

[0141] In some embodiments, when the first wall 201 is a cover sheet 211 , the end cover 21 includes a plastic part 204 , that is, the plastic part 204 is a part of the end cover 21 .

[0142] In some embodiments, the plastic member 204 is provided with a boss 2042 in a direction away from the first wall 201 , and the groove 2043 is provided on a side of the boss 2042 close to the first wall 201 .

[0143] The boss 2042 refers to a protruding structure provided on the plastic part 204 and protruding in a direction away from the first wall 201. The boss 2042 is provided so that when the battery cell 200 vibrates, the electrode assembly 30 vibrates in the housing 20 in a direction perpendicular to the first wall 201. The boss 2042 can limit the moving distance of the electrode assembly 30, thereby limiting the distance between the electrode assembly 30 and the first wall 201, and reserving an accommodation space for the upper tab 31 of the electrode assembly 30, thereby reducing the risk of the tab 31 being damaged by being squeezed.

[0144] The groove 2043 is disposed on the boss 2042 , which can fully utilize the volume of the boss 2042 , improve the integration level, and protect the bracket 205 through the boss 2042 .

[0145] The boss 2042 is provided on the plastic part 204 to limit the distance between the electrode assembly 30 and the first wall 201, so as to reserve a storage space for the pole ear 31 on the electrode assembly 30, so as to reduce the risk of damaging the pole ear 31; and the groove 2043 is provided on the boss 2042 to facilitate manufacturing, improve integration, and reduce the material used for the plastic part 204.

[0146] In some embodiments, when the first wall 201 is a cover sheet 211 , the end cover 21 includes a plastic part 204 , and a boss 2042 is provided on the plastic part 204 . When the end cover 21 is covered on the shell 22 , the boss 2042 can cooperate with the shell 22 to play a positioning role.

[0147] In some embodiments, the thickness of the plastic member 204 may be set to be larger, and a groove 2043 may be provided on the plastic member 204 to accommodate the bracket 205 .

[0148] In some embodiments, brackets 205 may be provided at both ends of the first wall 201 , respectively, so as to better depressurize and exhaust the first spaces 2001 at both ends of the battery cells 200 along the first direction P when the battery cells 200 thermally run away.

[0149] In some embodiments, the bosses 2042 on the plastic part 204 may correspond to the brackets 205 one by one to protect the corresponding brackets 205. Of course, the number of bosses 2042 may be set to be greater than the number of brackets 205 to better define the distance between the first wall 201 and the electrode assembly 30, thereby reducing the risk of damaging the tabs 31 when the battery cell 200 vibrates.

[0150] See also Figure 3 and Figure 6 In some embodiments, the adapter 40 includes a main body portion 41 and a connecting portion 42 that are connected to each other, the main body portion 41 is connected to the electrode assembly 30 , and the connecting portion 42 is connected to the electrode terminal 203 .

[0151] The main body 41 refers to the portion of the adapter 40 used to connect with the electrode assembly 30, specifically the portion of the adapter 40 connected with the tab 31 of the electrode assembly 30. The main body 41 is generally provided in a sheet or plate shape to facilitate connection with the tab 31.

[0152] The connection portion 42 refers to a portion of the adapter 40 used to connect to the electrode terminal 203. The connection portion 42 can be configured in a block shape, a column shape, or the like.

[0153] The main body 41 is provided to be connected to the electrode assembly 30 , and the connecting portion 42 is provided to be connected to the electrode terminal 203 , thereby achieving electrical connection between the electrode terminal 203 and the electrode assembly 30 .

[0154] See also Figure 3 and Figure 6 In some embodiments, the connecting portion 42 and the main body portion 41 are an integrally formed structure.

[0155] The connecting portion 42 and the main body 41 are an integrally formed structure, which can facilitate the processing and manufacturing of the adapter 40 and facilitate the connection with the electrode terminal 203 .

[0156] In some embodiments, the adapter 40 can be formed by stamping a metal plate, such as a copper plate, an aluminum plate, etc., to form a main body 41 and a connecting portion 42, so as to realize an integral forming of the main body 41 and the connecting portion 42, which is convenient for processing and manufacturing. Of course, in some embodiments, a block-shaped or plate-shaped conductive member can also be used as the adapter 40, and a part of its area is connected to the electrode terminal 203 as the connecting portion 42, and the other area is connected to the electrode assembly 30 as the main body 41.

[0157] In some embodiments, the connection portion 42 and the main body portion 41 may also be manufactured separately, and then the connection portion 42 and the main body portion 41 are connected by welding or bonding.

[0158] See also Fig.15 In some embodiments, the connection portion 42 and the electrode terminal 203 are integrally formed. For example, the electrode terminal 203 may be extended toward the electrode assembly 30 and protrude from the first wall 201 to serve as the connection portion 42 connected to the main body 41 .

[0159] The connecting portion 42 and the electrode terminal 203 are integrally formed to facilitate the processing and manufacturing of the main body 41 , and also facilitate the connection between the connecting portion 42 and the electrode terminal 203 , thereby electrically connecting the main body 41 and the electrode terminal 203 .

[0160] See also Figures 10 to 13 In some embodiments, the thickness of the side wall of the bracket 205 close to the first wall 201 is T1, the height of the exhaust channel 2051 along the thickness direction K of the first wall 201 is H1, the height of the connecting portion 42 protruding from the first wall 201 toward the electrode assembly 30 is H2, the thickness of the main body 41 is T2, and T1+H1>T2+H2.

[0161] The side wall of the bracket 205 close to the first wall 201 is also the side wall of the exhaust channel 2051 close to the first wall 201, and the thickness of the side wall determines the distance from the exhaust channel 2051 to the first wall 201. The thickness of the side wall of the bracket 205 close to the first wall 201 is T1, and the distance from the exhaust channel 2051 to the first wall 201 is also T1.

[0162] The height of the exhaust channel 2051 along the thickness direction K of the first wall 201 is H1, and the distance from the side of the exhaust channel 2051 away from the first wall 201 to the first wall 201 is H1+T1.

[0163] The height of the connecting portion 42 protruding from the first wall 201 toward the electrode assembly 30 is H2, that is, the height of the connecting portion 42 protruding from the inner surface of the first wall 201 is H2, and the main body 41 is connected to the connecting portion 42. When the main body 41 is in a flat state, the height of the connecting portion 42 protruding from the inner surface of the first wall 201 is also the height from the main body 41 to the first wall 201.

[0164] The thickness of the main body 41 is T2. When the main body 41 is in a flat state, the distance from the main body 41 away from the first wall 201 to the first wall 201 is T2+H2.

[0165] By making T1+H1>T2+H2, the main body 41 can be away from one side of the first wall 201 and the exhaust channel 2051 can be away from the side wall of the first wall 201, and there can be a spacing distance along the thickness direction K of the first wall 201, so that the gas flowing out of the exhaust channel 2051 can flow from this spacing distance and reach the pressure relief mechanism 202 for discharge, that is, the gas flowing out of the exhaust channel 2051 can flow from the side of the main body 41 close to the electrode assembly 30 to the pressure relief mechanism 202, so as to relieve the pressure of the first space 2001.

[0166] See also Figure 7 , Figures 10 to 13 In some embodiments, a central plane M1 of the bracket 205 along the second direction Q coincides with a central plane M2 of the connecting portion 42 along the second direction Q.

[0167] The central plane M1 of the bracket 205 along the second direction Q means that the central plane M1 of the bracket 205 is located at a middle position of the bracket 205 along the second direction Q.

[0168] The coincidence of the center plane M2 of the connection portion 42 along the second direction Q means that the center plane M2 of the connection portion 42 is located at the middle position of the connection portion 42 along the second direction Q. For example, when the connection portion 42 is truncated cone-shaped, the center plane M2 passes through the central axis of the connection portion 42 and is perpendicular to the second direction Q.

[0169] Since the strength of the connecting portion 42 in the thickness direction K of the battery cell 200 on the first wall 201 is greater relative to the main body 41, the connecting portion 42 is more difficult to deform in the later stage of thermal runaway of the battery cell 200. In this way, the space on the side of the connecting portion 42 away from the first wall 201 is more difficult to be blocked. Then, along the second direction Q, the center plane M1 of the bracket 205 is made to coincide with the center plane M2 of the connecting portion 42. Then, the gas flowing out of the exhaust channel 2051 can easily flow from the side of the connecting portion 42 away from the first wall 201, and reach the pressure relief mechanism 202 faster, so as to exhaust and relieve the pressure of the first space 2001.

[0170] See also Figure 7 , Fig.10 and Fig.11 In some embodiments, the diameter of the connecting portion 42 near the main body 41 is L, and the width of the exhaust channel 2051 along the second direction Q is W, L <W,T1<H2。

[0171] Since the connecting portion 42 is close to one end of the main body 41, it is easier to block the exhaust channel 2051 in the first direction P. The diameter L of the connecting portion 42 close to one end of the main body 41 is set to be smaller than the width W of the exhaust channel 2051 along the second direction Q, and the thickness T1 of the side wall of the bracket 205 close to the first wall 201 is set to be smaller than the height H2 of the connecting portion 42 protruding from the first wall 201. In this way, there can be a gap between the opposite sides of the connecting portion 42 along the second direction Q and the opposite side walls of the exhaust channel 2051 along the second direction Q that is not blocked by the connecting portion 42, so that the gas flowing out of the exhaust channel 2051 can pass through.

[0172] In addition, in the later stage of thermal runaway of the battery cell 200, the electrode assembly 30 pushes the adapter 40. Since the strength of the connecting portion 42 is relatively large, and the main body 41 is pushed by the electrode assembly 30, it will gradually bend from the end of the connecting portion 42 close to the main body 41 toward the first wall 201. This will form a gap space 401 between the opposite sides of the connecting portion 42, the main body 41 and the first wall 201, or form a gap space 401 between the side of the connecting portion 42 and the side of the main body 41 facing the first wall 201. After the gas in the first space 2001 flows out through the exhaust channel 2051, it will also flow from the gap space 401 to the second space 2002, and then be discharged through the pressure relief mechanism 202, so as to relieve the pressure of the first space 2001.

[0173] The diameter L of the connecting portion 42 near one end of the main body 41 is set to be smaller than the length W of the exhaust channel 2051, and the thickness T1 of the side wall of the bracket 205 near the first wall 201 is set to be smaller than the height H2 of the connecting portion 42 protruding from the first wall 201. This allows the gas flowing out of the exhaust channel 2051 to pass through the area formed between the side of the connecting portion 42 near the first wall 201 and the two sides of the connecting portion 42 along the second direction Q, thereby reducing the obstruction to the gas flowing out of the exhaust channel 2051 and further improving the exhaust rate of the first space 2001.

[0174] In some embodiments, L / W≤0.95, that is, the ratio of the diameter L of the connecting portion 42 at one end close to the main body 41 to the width W of the exhaust channel 2051 is less than or equal to 0.95, such as L / W can be 0.95, 0.9, 0.8, 0.7, 0.6, 0.5, 0.4, 0.3, etc., so that the connecting portion 42 has good structural strength, and the distance between the opposite sides of the connecting portion 42 along the second direction Q and the opposite side walls of the exhaust channel 2051 along the second direction Q that are not blocked by the connecting portion 42 is larger, so as to facilitate the passage of gas out of the exhaust channel 2051.

[0175] By setting the diameter L of the connecting portion 42 near one end of the main body 41 to be less than or equal to 0.95 of the length W of the exhaust channel 2051, a larger space can be provided between the side of the main body 41 near the first wall 201 and the two sides of the connecting portion 42 along the second direction Q for gas circulation, thereby reducing obstruction to the outflow of gas from the exhaust channel 2051 and facilitating the exhaust rate of the first space 2001.

[0176] See also Figure 7 and Fig.12 In some embodiments, the diameter of one end of the connecting portion 42 close to the main body 41 is L, the width of the exhaust channel 2051 along the second direction Q is W, and L≥W.

[0177] By setting the diameter L of the connecting portion 42 near one end of the main body 41 to be greater than or equal to the length W of the exhaust channel 2051 , the connecting portion 42 can be made larger to facilitate connection with the electrode terminal 203 , and the connection strength between the connecting portion 42 and the electrode terminal 203 can be improved, thereby reducing the internal resistance of the battery cell 200 .

[0178] See also Figure 7 , Figures 10 to 13 , in some embodiments, (H2+T2-T1) / H1≤0.5.

[0179] When the main body 41 is in a flat state, the distance from the main body 41 away from the first wall 201 to the first wall 201 is T2 + H2. The height of the projection of the adapter 40 on the exhaust channel 2051 along the first direction P along the thickness direction K of the first wall 201 is H2+T2-T1, so that (H2+T2-T1) / H1≤0.5, then the ratio of the height of the projection of the adapter 40 on the exhaust channel 2051 along the first direction P along the thickness direction K of the first wall 201 to the height H1 of the exhaust channel 2051 is less than or equal to 0.5, such as (H2+T2-T1) / H1 can be 0.5, 0.45, 0.4, 0.35, 0.3, 0.25, 0.2, 0.15, 0.1, etc., so that the area of ​​the exhaust channel 2051 blocked by the adapter 40 in the first direction P is smaller, so as to facilitate the gas flowing out of the exhaust channel 2051 to reach the pressure relief mechanism 202 through the adapter 40.

[0180] If (H2+T2-T1) / H1≤0.5, the distance from the side of the main body 41 away from the first wall 201 to the side wall of the exhaust channel 2051 away from the first wall 201 along the thickness direction K of the first wall 201 is greater than or equal to half of the height H1 of the exhaust channel 2051, thereby making the area of ​​the adapter 40 blocking the gas outflowing from the exhaust channel 2051 smaller, thereby facilitating the exhaust rate of the first space 2001.

[0181] See also Figure 7 and Fig.13 In some embodiments, H2≤T1. If H2≤T1, along the first direction P, the connection portion 42 is located in the area where the side wall of the bracket 205 close to the first wall 201 is located, so that the connection portion 42 can greatly reduce the obstruction of the gas flowing out of the exhaust channel 2051, so that the gas flowing out of the exhaust channel 2051 can reach the second space 2002, which is convenient for the exhaust rate of the first space 2001.

[0182] See also Figure 7 , Fig.11 and Fig.14 In some embodiments, the thickness of the side wall of the bracket 205 close to the first wall 201 is T1, the height of the exhaust channel 2051 along the thickness direction K of the first wall 201 is H1, the height of the connecting portion 42 protruding from the first wall 201 toward the electrode assembly 30 is H2, the thickness of the main body 41 is T2, the center plane of the bracket 205 along the second direction Q coincides with the center plane of the connecting portion 42 along the second direction Q, the diameter of one end of the connecting portion 42 close to the main body 41 is L, the width of the exhaust channel 2051 along the second direction Q is W, and T1+H1≤T2+H2, L <W。

[0183] The distance H1+T1 from the exhaust channel 2051 away from the first wall 201 to the first wall 201 is less than or equal to the distance T2+H2 from the main body 41 away from the first wall 201 to the first wall 201. The diameter L of the connecting portion 42 close to one end of the main body 41 is set to be smaller than the length W of the exhaust channel 2051. This allows a gap to exist between the opposite sides of the connecting portion 42 along the second direction Q and the opposite side walls of the exhaust channel 2051 in the second direction Q that is not blocked by the connecting portion 42, so that gas flowing out of the exhaust channel 2051 can pass through. Furthermore, in the later stage of thermal runaway of the battery cell 200, the electrode assembly 30 pushes the adapter 40. Since the strength of the connecting portion 42 is relatively large, and the main body 41 is pushed by the electrode assembly 30, it will gradually bend from the end of the connecting portion 42 close to the main body 41 toward the direction of the first wall 201. This will form a gap space 401 between the opposite sides of the connecting portion 42, the main body 41 and the first wall 201, or form a gap space 401 between the side of the connecting portion 42 and the side of the main body 41 facing the first wall 201. After the gas in the first space 2001 flows out through the exhaust channel 2051, it will also flow from the gap space 401 to the second space 2002, and then be discharged through the pressure relief mechanism 202, so as to relieve the pressure of the first space 2001.

[0184] Since the adapter 40 connects the electrode terminal 203 and the electrode assembly 30 , during the assembly process, the electrode assembly 30 is placed in the housing 20 and supported by the side wall of the housing 20 , and there is a certain distance between the electrode assembly 30 and the first wall 201 . Through the above-mentioned structural setting, the connecting portion 42 is set to be longer, and the main body 41 is connected to the connecting portion 42, so that the main body 41 can be closer to the electrode assembly 30, so as to facilitate the connection between the main body 41 and the electrode assembly 30, and also facilitate the connection between the connecting portion 42 and the electrode terminal 203 on the first wall 201; in addition, with this structural setting, in the case of thermal runaway of the battery cell 200, if the pole piece of the electrode assembly 30 moves toward the first wall 201 and pushes the main body 41 of the adapter 40, due to the supporting effect of the connecting portion 42, when the main body 41 bends toward the first wall 201, there will be a gap space 401 between the opposite sides of the connecting portion 42 and the bent main body 41 for gas circulation, so that the gas flowing out of the exhaust channel 2051 reaches the second space 2002, so as to exhaust and relieve the pressure of the first space 2001.

[0185] In some embodiments, L / W≤0.95, that is, the ratio of the diameter L of the connecting portion 42 at one end close to the main body 41 to the width W of the exhaust channel 2051 is less than or equal to 0.95, such as L / W can be 0.95, 0.9, 0.8, 0.7, 0.6, 0.5, 0.4, 0.3, etc., so that the connecting portion 42 has good structural strength, and the distance between the opposite sides of the connecting portion 42 along the second direction Q and the opposite side walls of the exhaust channel 2051 along the second direction Q that are not blocked by the connecting portion 42 is larger, so as to facilitate the passage of gas out of the exhaust channel 2051.

[0186] By setting the diameter L of the connecting portion 42 at one end close to the main body 41 to be less than or equal to 0.95 of the length W of the exhaust channel 2051, the space between the two opposite sides of the connecting portion 42 and the main body 41 can have a larger facing area with the exhaust channel 2051 to provide gas circulation, reduce obstruction to the outflow of gas from the exhaust channel 2051, and facilitate exhaust and pressure relief of the first space 2001.

[0187] In some embodiments, the height H2 of the connection portion 42 protruding from the first wall 201 toward the electrode assembly 30 is in the range of 0.3 mm to 2 mm.

[0188] The height H2 of the connecting portion 42 protruding from the first wall 201 in the direction toward the electrode assembly 30 is also the height of the connecting portion 42 protruding from the inner surface of the first wall 201, and the height is set to 0.3mm-2mm, such as H2 can be 0.3mm, 0.4mm, 0.5mm, 0.6mm, 0.7mm, 0.8mm, 0.9mm, 1.0mm, 1.1mm, 1.2mm, 1.3mm, 1.4mm, 1.5mm, 1.6mm, 1.7mm, 1.8mm, 1.9mm, 2mm, etc. This can not only make the adapter 40 less obstructive to the exhaust channel 2051 in the first direction P, but also facilitate the connection between the connecting portion 42 and the electrode terminal 203.

[0189] In some embodiments, the height range of the connecting portion 42 protruding from the first wall 201 toward the electrode assembly 30 is 0.5mm-1.5mm. For example, the height H2 of the connecting portion 42 protruding from the first wall 201 toward the electrode assembly 30 can be 0.5mm, 0.6mm, 0.7mm, 0.8mm, 0.9mm, 1.0mm, 1.1mm, 1.2mm, 1.3mm, 1.4mm, or 1.5mm. This can make the adapter 40 less obstructive to the exhaust channel 2051 in the first direction P, and facilitate the connection between the connecting portion 42 and the electrode terminal 203.

[0190] See also Fig. 20In some embodiments, a center plane M1 of the bracket 205 along the second direction Q is spaced apart from a center plane M2 of the connecting portion 42 along the second direction Q, and a projection area of ​​the bracket 205 partially overlaps with a projection area of ​​the connecting portion 42 along the first direction P.

[0191] The center plane M1 of the bracket 205 along the second direction Q is spaced from the center plane M2 of the connecting portion 42 along the second direction Q, that is, the bracket 205 can be offset by a distance along the second direction Q to facilitate the position layout of the bracket 205 and the installation of the bracket 205; in the case of thermal runaway of the battery cell 200, if the pole piece of the electrode assembly 30 moves toward the first wall 201 and pushes the main body 41 of the adapter 40, due to the supporting effect of the connecting portion 42, when the main body 41 bends toward the first wall 201, there will also be gap spaces 401 between the opposite sides of the connecting portion 42 and the bent main body 41. In the first direction P, the projection area of ​​the bracket 205 is partially overlapped with the projection area of ​​the connecting portion 42, so that the gap space 401 on the side where the connecting portion 42 overlaps with the projection area of ​​the bracket 205 can be used for gas circulation, so that the gas flowing out of the exhaust channel 2051 reaches the second space 2002, so as to exhaust and depressurize the first space 2001.

[0192] In some embodiments, the diameter of the connecting portion 42 near one end of the main body 41 is L, the distance between the center plane M1 of the bracket 205 along the second direction Q and the center plane M2 of the connecting portion 42 along the second direction Q is D, and D≤L / 2, that is, D / L≤0.5, such as D / L can be 0.5, 0.4, 0.3, 0.2, 0.1, etc.

[0193] By setting the distance D between the center plane M1 of the bracket 205 along the second direction Q and the center plane M2 of the connecting portion 42 along the second direction Q to be less than or equal to half of the diameter L of the connecting portion 42 at one end close to the main body 41, the projection area of ​​the bracket 205 along the first direction P can overlap at least half of the connecting portion 42. Therefore, in the case of thermal runaway of the battery cell 200, if the pole piece of the electrode assembly 30 moves toward the first wall 201 and pushes the main body 41 of the adapter 40, due to the supporting effect of the connecting portion 42, when the main body 41 bends toward the first wall 201, there will also be gap spaces 401 between the opposite sides of the connecting portion 42 and the bent main body 41, so that the gap space 401 on the side where the connecting portion 42 at least overlaps with the projection area of ​​the bracket 205 can have a larger area in the first direction P to face the exhaust channel 2051, which can reduce the obstruction to the gas flow, and further make it easier for the gas flowing out of the exhaust channel 2051 to flow to the second space 2002, so as to exhaust and depressurize the first space 2001.

[0194] See also Figure 5 , Fig.16 and Fig. 20 In some embodiments, a notch 2052 communicating with the exhaust channel 2051 is provided on a side of the bracket 205 facing away from the first wall 201 .

[0195] The notch 2052 refers to an opening structure provided on the bracket 205 . The notch 2052 is connected to the exhaust passage 2051 , and the peripheral side of the bracket 205 is in a disconnected state at the notch 2052 .

[0196] A notch 2052 is provided on the side of the bracket 205 away from the first wall 201, so that the area of ​​gas circulation can be increased to facilitate exhaust; in addition, when the bracket 205 is made of profile, the notch 2052 can be positioned, and it is also convenient to process and manufacture the bracket 205. When the bracket 205 is made of sheet metal impact, it can be easily bent, which is also convenient for processing and manufacturing the bracket 205.

[0197] See also Fig.16 and Fig. 20 In some embodiments, exhaust channels 2051 are respectively provided at both ends of the bracket 205 along the second direction Q.

[0198] Exhaust channels 2051 are provided at both ends of the bracket 205 to better divert the gas flowing out of the exhaust channel 2051 , thereby reducing the obstruction of the adapter 40 to the gas, facilitating the gas to flow to the second space 2002 , and then being arranged from the pressure relief mechanism 202 , facilitating the pressure relief of the first space 2001 .

[0199] In some embodiments, the cross-section of the exhaust channel 2051 is triangular.

[0200] The cross section of the exhaust channel 2051 refers to a cross section perpendicular to the direction in which the exhaust channel 2051 extends, and also refers to a cross section perpendicular to the first direction P.

[0201] The cross section of the exhaust channel 2051 is set to be triangular, and the side walls surrounding the exhaust channel 2051 are also triangular, which can make the structure of the exhaust channel 2051 more stable and facilitate gas circulation.

[0202] In some embodiments, a support rib 2053 is disposed in the exhaust channel 2051 , and the support rib 2053 extends along the first direction P.

[0203] The support ribs 2053 refer to ribs disposed in the bracket 205 to increase the structural strength of the bracket 205 .

[0204] Support ribs 2053 are provided in the exhaust passage 2051 to increase the structural strength of the bracket 205 and reduce the risk of deformation due to extrusion of the electrode assembly 30 .

[0205] In some embodiments, the number of support ribs 2053 in the exhaust passage 2051 can be set to one, two, three, etc., and can be specifically set according to needs.

[0206] In some embodiments, the bracket 205 can be made of profiles to facilitate processing and production.

[0207] According to some embodiments of the present application, the present application provides a battery cell 200, including a housing 22, an electrode assembly 30, an end cap 21, and an adapter 40; the electrode assembly 30 is accommodated in the housing 22, and a first space 2001 is formed between the end face of the electrode assembly 30 in the length direction X and the side wall of the housing 22. The end cap 21 includes a cover plate 211, an electrode terminal 203, a bracket 205, and a pressure relief mechanism 202. The cover plate 211 is disposed on the housing 22, and the electrode terminal 203, the bracket 205, and the pressure relief mechanism 202 are all disposed on the cover plate 211. A second space 2002 is formed between the pressure relief mechanism 202 and the electrode assembly 30. The bracket 205 is provided with an exhaust passage 2051 extending along the length direction X of the cover plate 211. The bracket 205 is used to abut against one side of the electrode assembly 30 facing the cover plate 211, so that the exhaust passage 2051 communicates the first space 2001 with the second space 2002. The adapter 40 is disposed between the bracket 205 and the pressure relief mechanism 202 and is connected between the electrode assembly 30 and the electrode terminal 203. The adapter 40 includes a main body portion 41 and a connecting portion 42 connected to each other. The main body portion 41 is connected to the electrode assembly 30, and the connecting portion 42 is connected to the electrode terminal 203. The central plane M1 of the bracket 205 along the width direction Y of the cover plate 211 coincides with the central plane M2 of the connecting portion 42 along the width direction Y of the cover plate 211. The thickness of the side wall of the bracket 205 close to the cover plate 211 is T1, the height of the exhaust passage 2051 along the thickness direction Z of the cover plate 211 is H1, the height of the connecting portion 42 protruding from the cover plate 211 in the direction facing the electrode assembly 30 is H2, the thickness of the main body portion 41 is T2, the diameter of the connecting portion 42 close to one end of the main body portion 41 is L, the width of the exhaust passage 2051 along the width direction Y of the cover plate 211 is W, and T1 + H1 > T2 + H2, L < W, T1 < H2. Thus, the gas flowing out of the exhaust passage 2051 can flow from the side of the main body portion 41 close to the electrode assembly 30 to the pressure relief mechanism 202, and can also pass through the area formed between the side of the connecting portion 42 close to the cover plate 211 and the two sides of the connecting portion 42 along the width direction Y of the cover plate 211, and can also pass through, so as to reduce the obstruction to the gas flowing out of the exhaust passage 2051, further improve the exhaust rate of the first space 2001, and reduce the risk of the outer shell 20 of the battery cell 200 bursting due to excessive pressure in the first space 2001.

[0208] According to some embodiments of the present application, the present application further provides a battery, including the battery cell described in any of the above solutions.

[0209] According to some embodiments of the present application, the present application also provides an electrical device, comprising the battery described in any of the above schemes.

[0210] The power-consuming device may be any of the aforementioned devices or systems using batteries.

[0211] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present application, rather than to limit them; although the present application has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or replace some or all of the technical features therein by equivalents; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the scope of the technical solutions of the embodiments of the present application, and they should all be included in the scope of the claims and specification of the present application. In particular, as long as there is no structural conflict, the various technical features mentioned in the various embodiments can be combined in any way. The present application is not limited to the specific embodiments disclosed herein, but includes all technical solutions that fall within the scope of the claims.

Claims

1. A battery cell, characterized in that: include: shell; An electrode assembly is accommodated in the shell, and a first space is formed between an end surface of the electrode assembly in a first direction and a side wall of the shell; The housing has a first wall, an electrode terminal is disposed on the first wall, a bracket is disposed at an end of the first wall along the first direction, a pressure relief mechanism is disposed on the first wall, a second space is formed between the pressure relief mechanism and the electrode assembly, an exhaust passage extending along the first direction is provided on the bracket, and the bracket is used to abut against a side of the electrode assembly facing the first wall so that the exhaust passage connects the first space with the second space; An adapter is arranged between the bracket and the pressure relief mechanism and connected between the electrode assembly and the electrode terminal; along the first direction, the projection area of ​​the adapter in the exhaust channel is smaller than the cross-sectional area of ​​the exhaust channel.

2. The battery cell according to claim 1, characterized in that: The adapter includes a main body portion and a connecting portion which are connected to each other, the main body portion is connected to the electrode assembly, and the connecting portion is connected to the electrode terminal.

3. The battery cell according to claim 2, characterized in that: The thickness of the side wall of the bracket close to the first wall is T1, the height of the exhaust channel along the thickness direction of the first wall is H1, the height of the connecting portion protruding from the first wall toward the electrode assembly is H2, the thickness of the main body is T2, and T1+H1>T2+H2.

4. The battery cell according to claim 3, characterized in that: A central plane of the bracket along a second direction coincides with a central plane of the connecting portion along the second direction, and the second direction is perpendicular to the first direction.

5. The battery cell according to claim 4, characterized in that: The diameter of the connecting portion close to one end of the main body is L, the width of the exhaust passage along the second direction is W, and L <W,T1<H2。 6. The battery cell according to claim 5, characterized in that: L / W≤0.

95.

7. The battery cell according to claim 4, characterized in that: The diameter of one end of the connecting portion close to the main body portion is L, the width of the exhaust passage along the second direction is W, and L≥W.

8. The battery cell according to any one of claims 3 to 7, characterized in that: (H2+T2-T1) / H1≤0.

5.

9. The battery cell according to claim 3, 4 or 7, characterized in that: H2≤T1.

10. The battery cell according to claim 2, characterized in that: The thickness of the side wall of the bracket close to the first wall is T1, the height of the exhaust channel along the thickness direction of the first wall is H1, the height of the connecting portion protruding from the first wall toward the electrode assembly is H2, the thickness of the main body is T2, the center plane of the bracket along the second direction coincides with the center plane of the connecting portion along the second direction, the diameter of one end of the connecting portion close to the main body is L, the width of the exhaust channel along the second direction is W, and T1+H1≤T2+H2, L <W。 11. The battery cell according to claim 10, characterized in that: L / W≤0.

95.

12. The battery cell according to claim 2 or 3, characterized in that: The center plane of the bracket along the second direction is spaced from the center plane of the connecting portion along the second direction, and the projection area of ​​the bracket partially overlaps with the projection area of ​​the connecting portion along the first direction, and the second direction is perpendicular to the first direction.

13. The battery cell according to claim 12, characterized in that: The diameter of the connecting portion close to one end of the main body is L, the distance between the center plane of the bracket along the second direction and the center plane of the connecting portion along the second direction is D, and D≤L / 2.

14. The battery cell according to any one of claims 2 to 7, 10, 11 or 13, characterized in that: The connecting portion protrudes from the first wall in a direction toward the electrode assembly by a height ranging from 0.3 mm to 2 mm.

15. The battery cell according to claim 14, characterized in that: The connecting portion protrudes from the first wall in a direction toward the electrode assembly by a height ranging from 0.5 mm to 1.5 mm.

16. The battery cell according to any one of claims 2 to 7, 10, 11, 13 or 15, characterized in that: The connecting portion and the main body are an integrally formed structure; or, the connecting portion and the electrode terminal are an integrally formed structure.

17. The battery cell according to any one of claims 1 to 7, 10, 11, 13 or 15, characterized in that: The bracket is a metal bracket or a ceramic bracket.

18. The battery cell according to any one of claims 1 to 7, 10, 11, 13 or 15, characterized in that: A notch communicating with the exhaust passage is provided on a side of the bracket facing away from the first wall.

19. The battery cell according to any one of claims 1 to 7, 10, 11, 13 or 15, characterized in that: The exhaust channels are respectively disposed at two ends of the bracket along a second direction, and the second direction is perpendicular to the first direction.

20. The battery cell according to claim 19, characterized in that The cross section of the exhaust passage is triangular.

21. The battery cell according to any one of claims 1 to 7, 10, 11, 13, 15 or 20, characterized in that: The exhaust passage is provided with a support rib, and the support rib is extended along the first direction.

22. The battery cell according to any one of claims 1 to 7, 10, 11, 13, 15 or 20, characterized in that: A plastic part is provided on the first wall, and the plastic part is installed on a side of the first wall close to the bracket. A through hole is provided on the plastic part, and the adapter is connected to the electrode terminal through the through hole. The plastic part is provided with a groove for the bracket to be placed.

23. The battery cell according to claim 22, characterized in that: The plastic part is provided with a boss in a direction away from the first wall, and the groove is provided on a side of the boss close to the first wall.

24. A battery, characterized in that: Comprising the battery cell according to any one of claims 1-23.

25. An electrical device, characterized in that: Comprising a battery as claimed in claim 24.

Images