Battery cell, battery, and electric device

Abstract

Provided are a battery cell, a battery, and an electric device, capable of improving the reliability of battery cells. The battery cell comprises: a casing, the casing having a first wall, and a pressure relief mechanism being arranged on the first wall; an electrode assembly, the electrode assembly being accommodated in the casing; an insulating member, the insulating member being arranged between the electrode assembly and the first wall, the insulating member having an accommodating cavity, and the insulating member having a discharge passage communicated with the pressure relief mechanism and the electrode assembly; and a supporting member, the supporting member being accommodated in the accommodating cavity and used for limiting the deformation of the discharge passage.

Description

Battery cells, batteries and electrical devices

[0001] This application claims priority to the Chinese patent application filed with the State Intellectual Property Office of China on August 16, 2023, with application number 202311034083.1 and application name “Battery Cell, Battery and Electrical Device”, the entire contents of which are incorporated by reference into this application. Technical Field

[0002] The embodiments of the present application relate to the field of batteries, and more specifically, to a battery cell, a battery, and an electrical device. Background Art

[0003] Energy conservation and emission reduction are key to the sustainable development of the automotive industry. In this context, electric vehicles, due to their energy-saving and environmentally friendly advantages, have become a crucial component of the industry's sustainable development. Battery technology, in turn, is a crucial factor in the development of electric vehicles.

[0004] With the development of battery technology, various battery performance indicators are constantly improving. During battery use, the reliability of the electrical performance of battery cells is an important factor in measuring battery quality. Therefore, how to improve the reliability of battery cells remains an unresolved issue.

[0005] Summary of the Invention

[0006] The embodiments of the present application provide a battery cell, a battery, and an electrical device, which can improve the reliability of the battery cell.

[0007] In a first aspect, a battery cell is provided, comprising: a shell having a first wall, on which a pressure relief mechanism is provided; an electrode assembly, which is accommodated in the shell; an insulating member, which is arranged between the electrode assembly and the first wall, the insulating member having a accommodating cavity, and the insulating member having a discharge channel connecting the pressure relief mechanism and the electrode assembly; and a support member, which is accommodated in the accommodating cavity and is used to limit deformation of the discharge channel.

[0008] The battery cell provided in the embodiment of the present application can limit the deformation of the discharge channel through the support member when thermal runaway occurs inside the battery cell, reducing the possibility of the discharge channel or the pressure relief structure being blocked by the electrode assembly, which is conducive to the actuation of the pressure relief mechanism to quickly discharge high-temperature and high-pressure substances inside the battery cell, thereby improving the reliability of the battery cell.

[0009] In some embodiments, the insulating member includes a first insulating wall, and the accommodating cavity is formed between the first insulating wall and the first wall.

[0010] The first insulating wall can provide support for the supporting member, reduce the possibility of the supporting member falling from the accommodating cavity, and help maintain the position of the supporting member relative to the insulating member, thereby improving the effect of the supporting member in limiting deformation of the exhaust channel.

[0011] In some embodiments, a projection of the first insulating wall in the thickness direction of the first wall covers a projection of the supporting member in the thickness direction of the first wall.

[0012] This can ensure better insulation performance between the electrode assembly and the first wall, reduce the possibility of the first wall being charged due to contact between the electrode assembly and the support member, or between the support member and the first wall, and help improve the reliability of the battery cell.

[0013] In some embodiments, the insulating component includes a second insulating wall, which is disposed between the first insulating wall and the first wall, and forms the accommodating cavity between the second insulating wall and the first insulating wall.

[0014] The second insulating wall can isolate the support member from the first wall, improving the insulation performance between the support member and the first wall. At the same time, the accommodation cavity formed by the second insulating wall and the first insulating wall can provide a more stable accommodation space for the support member, making it less likely to fall during assembly.

[0015] In some embodiments, the insulating member includes a second insulating wall, which is arranged on the surface of the insulating member facing the first wall in the thickness direction of the first wall, and the accommodating cavity is formed between the second insulating wall and the surface of the insulating member facing the electrode assembly in the thickness direction of the first wall.

[0016] The second insulating wall can separate the support member from the first wall and play an insulating role between the support member and the first wall, so that the first wall is not easily charged, thereby improving the reliability of the battery cell.

[0017] In some embodiments, the insulating member includes a connecting wall connecting the first insulating wall and the second insulating wall, and the connecting wall extends along the first direction.

[0018] The connecting wall can improve the anti-deformation strength of the insulating member in the thickness direction of the first wall, and provide support for the supporting member accommodated in the accommodating cavity, so that the supporting member is not easy to fall.

[0019] In some embodiments, the connecting wall is provided with a discharge hole penetrating the connecting wall in a thickness direction of the connecting wall.

[0020] The discharge hole on the connecting wall can form a discharge channel together with the accommodating cavity, guiding the high-temperature and high-pressure material to flow toward the pressure relief mechanism, which is conducive to the actuation of the pressure relief structure to quickly discharge the high-temperature and high-pressure material inside the battery cell, thereby improving the reliability of the battery cell.

[0021] In some embodiments, the connecting wall includes a first connecting portion, which is arranged on both sides of the pressure relief mechanism in the length direction of the first wall, and the discharge hole includes a first through hole, which passes through the first connecting portion in the length direction of the first wall, and the first through hole is used to form the discharge channel.

[0022] The first connecting portion and the first through hole can form a discharge channel in the surrounding area of ​​the pressure relief mechanism, which is beneficial for guiding the high-temperature and high-pressure substances generated by thermal runaway to flow to the area of ​​the pressure relief mechanism when thermal runaway occurs inside the battery cell, so that the pressure relief mechanism can be actuated in time, thereby improving the reliability of the battery cell.

[0023] In some embodiments, the insulating member has a second through hole that penetrates the insulating member in the thickness direction of the first wall, the second through hole is arranged opposite to the pressure relief mechanism, and the second through hole is used to form the discharge channel.

[0024] The second through hole can more directly connect the pressure relief mechanism and the electrode assembly, so that the high-temperature and high-pressure material inside the battery cell can flow to the pressure relief mechanism faster, so that the pressure relief mechanism can be actuated in time, thereby improving the reliability of the battery cell.

[0025] In some embodiments, the support member is disposed on an edge of the insulating member on a plane perpendicular to a thickness direction of the first wall.

[0026] The support member is arranged at the edge of the insulating member and is not likely to interfere with other members in the battery cell, which is beneficial to improving the qualified rate of the battery cell.

[0027] In some embodiments, the support member is located at an edge of the insulating member in a width direction of the first wall.

[0028] Arranging the support member along the longer side of the insulating member can enable the support member to play a certain supporting role for the insulating member and the electrode assembly in a larger range, thereby limiting the deformation of the exhaust passage.

[0029] In some embodiments, the support members are spaced apart along the length of the first wall.

[0030] This can reduce the overall weight of the battery cell while limiting deformation of the exhaust channel.

[0031] In some embodiments, the support member is located at an edge of the insulating member in the length direction of the first wall.

[0032] The support member is arranged on the wide side of the insulating member to limit the deformation of the insulating member at the corresponding position of the insulating member, and at the same time limit the movement of the electrode assembly toward the pressure relief mechanism to a certain extent, reducing the probability of the electrode assembly blocking the pressure relief mechanism and keeping the discharge channel unobstructed.

[0033] In some embodiments, the support member is disposed in a surrounding area of ​​the pressure relief mechanism.

[0034] The support member disposed around the pressure relief mechanism can more directly restrict further movement of the electrode assembly near the pressure relief mechanism toward the mechanism, thereby limiting deformation of the vent channel near the mechanism. High-temperature, high-pressure substances within the battery cell can reach the pressure relief mechanism through the vent channel, allowing the pressure relief mechanism to activate and release the high-temperature, high-pressure substances within the battery cell, thereby improving the reliability of the battery cell.

[0035] In some embodiments, a plurality of the support members enclose a surrounding area of ​​the pressure relief mechanism to form a receiving space, and the pressure relief mechanism is disposed in the receiving space.

[0036] The multiple support members provided around the pressure relief mechanism can further limit the deformation of the structure around the pressure relief mechanism and keep the discharge channel in the area around the pressure relief mechanism unobstructed.

[0037] In some embodiments, the supporting member is provided with a third through hole, and the third through hole is used to form the exhaust channel.

[0038] The third through hole can provide a path for the high-temperature and high-pressure material to flow inside the battery cell, which is beneficial to the discharge of the high-temperature and high-pressure material, enables the pressure relief mechanism to be actuated in time, and improves the reliability of the battery cell.

[0039] In some embodiments, the support member includes an elongated main body.

[0040] The main body is long and narrow, which can limit the movement of the electrode assembly within a larger range without affecting the discharge capacity of the discharge channel, thereby keeping the discharge channel unobstructed, reducing the possibility of deformation of the discharge channel resulting in the inability to discharge high-temperature and high-pressure materials, and improving the reliability of the battery cell.

[0041] In some embodiments, the melting point of the support member is higher than the melting point of the insulating member.

[0042] In the same temperature environment, the supporting member is less likely to melt or dissolve than the insulating member, and can maintain its original shape and position in the accommodating cavity, thereby supporting the electrode assembly moving toward the pressure relief mechanism, making it difficult for the electrode assembly to move to a position that blocks the discharge channel, thereby limiting the deformation of the discharge channel and providing a discharge channel for high-temperature and high-pressure materials to reach the pressure relief mechanism, which is beneficial to improving the reliability of the battery cell.

[0043] In some embodiments, the melting point of the support member is greater than 100°C.

[0044] This is beneficial in that when the battery cell experiences thermal runaway, it is not easily melted, and an exhaust channel connected to the pressure relief mechanism can be formed between the first wall and the electrode assembly, so that the thermal runaway gas can be discharged to the outside of the battery cell through the pressure relief mechanism in a timely manner, which is beneficial to improving the reliability of the battery cell.

[0045] In some embodiments, the first wall is provided with an electrode terminal, and the battery cell includes: a connecting member, the connecting member is used to electrically connect the electrode terminal and the electrode assembly, the insulating member has a avoidance hole that penetrates the insulating member in the first direction, and at least a portion of the connecting member is accommodated in the avoidance hole.

[0046] The avoidance hole can provide space for the connecting member to electrically connect the electrode terminal and the electrode assembly, so that the electric energy generated in the electrode assembly can be led out of the battery cell to provide electric energy to the electric device.

[0047] In some embodiments, the support member is interference fit with the accommodating cavity.

[0048] This makes it easier to fix the support member in the accommodating cavity, making it less likely for the support member to fall out of the accommodating cavity. This is beneficial for keeping the discharge channel unobstructed when high-temperature and high-pressure substances are generated inside the battery cell, and is beneficial for improving the reliability of the battery cell.

[0049] In some embodiments, a surface of the support member facing the electrode assembly in the thickness direction of the first wall and / or a surface of the support member facing the first wall in the thickness direction of the first wall has an insulating layer.

[0050] The insulating layer can improve the insulation performance between the support member and the first wall, reduce the possibility that the outer shell of the battery cell is charged through the support member, and thus improve the reliability of the battery cell.

[0051] In a second aspect, a battery is provided, comprising: a battery cell as described in any embodiment of the first aspect.

[0052] In a third aspect, an electrical device is provided, comprising a battery as described in any embodiment of the second aspect, wherein the battery is used to provide electrical energy to the electrical device. BRIEF DESCRIPTION OF THE DRAWINGS

[0053] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the following is a brief introduction to the drawings required for use in the embodiments of the present application. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on the drawings without creative work.

[0054] FIG1 is a schematic structural diagram of a vehicle provided in an embodiment of the present application.

[0055] FIG2 is a schematic structural diagram of a battery provided in an embodiment of the present application.

[0056] FIG3 is a schematic diagram of the exploded structure of a battery cell provided in an embodiment of the present application.

[0057] FIG4 is a schematic diagram of the exploded structure of a first wall, an insulating member, and a supporting member provided in an embodiment of the present application.

[0058] FIG5 is a schematic structural diagram of a first wall, an insulating member, and a supporting member provided in an embodiment of the present application.

[0059] FIG6 is a simplified structural diagram of an emission path provided in an embodiment of the present application.

[0060] FIG7 is a schematic structural diagram of another first wall, insulating member and supporting member provided in an embodiment of the present application.

[0061] FIG. 8 is a view of the structure in FIG. 7 along the thickness direction of the first wall.

[0062] FIG9 is a cross-sectional view of the structure in FIG8 along the AA direction.

[0063] FIG10 is another cross-sectional view of the structure in FIG8 along the AA direction.

[0064] FIG. 11 is an axonometric view corresponding to the structure shown in FIG. 10 .

[0065] FIG12 is another cross-sectional view of the structure in FIG8 along the AA direction.

[0066] FIG13 is a schematic diagram of an exploded structure of the structure in FIG7 .

[0067] FIG14 is a schematic structural diagram of another first wall, insulating member and supporting member provided in an embodiment of the present application.

[0068] FIG15 is a schematic diagram of an exploded structure of the structure in FIG14 .

[0069] FIG16 is a schematic diagram of the exploded structure of another first wall, insulating member and supporting member provided in an embodiment of the present application.

[0070] FIG17 is a schematic diagram of the exploded structure of another first wall, insulating member and supporting member provided in an embodiment of the present application.

[0071] In the drawings, the drawings are not drawn to scale. DETAILED DESCRIPTION

[0072] The following detailed description of the embodiments of the present application is provided in conjunction with the accompanying drawings and examples. The following detailed description of the embodiments and the accompanying drawings are used to illustrate the principles of the present application, but are not intended to limit the scope of the present application, that is, the present application is not limited to the described embodiments.

[0073] In the description of this application, it should be noted that the terms "upper," "lower," "left," "right," "inner," "outer," etc., indicating directions or positional relationships, are used solely for the purpose of facilitating the description of this application and simplifying the description. They do not indicate or imply that the devices or components referred to must have a specific direction, be constructed, or operate in a specific direction. Therefore, they should not be construed as limiting this application. Furthermore, the terms "first," "second," "third," etc., are used for descriptive purposes only and should not be construed as indicating or implying relative importance. "Perpendicular" does not mean perpendicular in the strict sense, but rather within the tolerance range. "Parallel" does not mean parallel in the strict sense, but rather within the tolerance range. All technical and scientific terms used in this application have the same meanings as those commonly understood by those skilled in the art to which this application belongs. The terms used in this application and in the specification of the application are for the purpose of describing specific embodiments only and are not intended to limit this application. The terms "including," "having," and any variations thereof in the specification and claims of this application and the accompanying drawings are intended to cover non-exclusive inclusions.

[0074] The directional words appearing in the following description are all directions shown in the figures, and do not limit the specific structure of this application. In the description of this application, it should also be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection; it can be directly connected or indirectly connected through an intermediate medium. For ordinary technicians in this field, the specific meanings of the above terms in this application can be understood according to the specific circumstances.

[0075] References to "embodiments" in this application mean that a particular feature, structure, or characteristic described in connection with the embodiment may be included in at least one embodiment of the application. The appearance of this phrase in various places in the specification does not necessarily refer to the same embodiment, nor does it constitute an independent or alternative embodiment that is mutually exclusive of other embodiments. It is understood, both explicitly and implicitly, by those skilled in the art that the embodiments described in this application may be combined with other embodiments.

[0076] The term "multiple" in this application refers to more than two (including two). Similarly, "multiple groups" refers to more than two groups (including two groups), and "multiple pieces" refers to more than two pieces (including two pieces).

[0077] In the embodiments of this application, the same reference numerals represent the same components, and for the sake of brevity, detailed descriptions of the same components in different embodiments are omitted. It should be understood that the thickness, length, width, and other dimensions of the various components in the embodiments of this application, as well as the overall thickness, length, width, and other dimensions of the integrated device shown in the drawings are merely illustrative and should not constitute any limitation on this application.

[0078] In this application, battery cells may include lithium-ion secondary batteries, lithium-ion primary batteries, lithium-sulfur batteries, sodium-lithium-ion batteries, sodium-ion batteries, lithium metal batteries, or magnesium-ion batteries, etc., and the embodiments of this application do not limit this. Battery cells may be cylindrical, flat, rectangular, or other shapes, etc., and the embodiments of this application do not limit this. Battery cells are generally divided into three types based on the packaging method: cylindrical battery cells, prismatic battery cells, and soft-pack battery cells, and the embodiments of this application do not limit this.

[0079] The battery referred to in the embodiments of this application refers to a single physical module that includes one or more battery cells to provide higher voltage and capacity. For example, the battery referred to in this application may include a battery module or a battery pack. A battery generally includes a casing that encloses one or more battery cells. The casing prevents liquids or other foreign matter from affecting the charging or discharging of the battery cells.

[0080] A battery cell includes an electrode assembly and an electrolyte. The electrode assembly consists of a positive electrode sheet, a negative electrode sheet, and a separator. A battery cell primarily operates by the movement of metal ions between the positive and negative electrode sheets. The positive electrode sheet includes a positive current collector and a positive active material layer. The positive active material layer is coated on the surface of the positive electrode collector. The uncoated positive electrode collector protrudes from the coated positive electrode collector, and the uncoated positive electrode collector serves as the positive electrode tab. For lithium-ion batteries, for example, the positive electrode current collector can be made of aluminum, and the positive electrode active material can be lithium cobalt oxide, lithium iron phosphate, ternary lithium, or lithium manganese oxide. The negative electrode sheet includes a negative current collector and a negative active material layer. The negative active material layer is coated on the surface of the negative electrode collector. The uncoated negative electrode collector protrudes from the coated negative electrode collector, and the uncoated negative electrode collector serves as the negative electrode tab. The negative electrode current collector can be made of copper, and the negative electrode active material can be made of carbon, silicon, lithium metal, or a lithium alloy. To ensure that high current can pass without melting, the positive electrode tabs are multiple and stacked together, and the negative electrode tabs are multiple and stacked together. The separator can be made of polypropylene (PP) or polyethylene (PE). In addition, the electrode assembly in the embodiments of the present application includes but is not limited to a wound structure or a laminated structure.

[0081] During the use of battery cells, the battery cells may produce a large amount of high-temperature and high-pressure substances such as thermal runaway gases due to mechanical external forces or internal chemical reactions. These high-temperature and high-pressure substances need to pass through the gap between the electrode assembly and the shell, or the exhaust channel formed by the through-holes set in other structures to reach the pressure relief structure, and the high temperature or high pressure causes the pressure relief mechanism to be actuated to discharge the high-temperature and high-pressure substances inside the battery cells. However, as the energy density of battery cells continues to increase, the thermal runaway rate of battery cells continues to increase, and the gas production rate and gas production volume increase significantly. When the gas production rate and gas production volume are large enough, the electrode assembly may move toward the pressure relief mechanism under the drive of the high-temperature and high-pressure substances, blocking the pressure relief mechanism. Some structures in the battery cells used to form exhaust channels may also melt in a high-temperature environment, further reducing the amount of emissions, resulting in the battery cells being unable to quickly discharge high-temperature and high-pressure substances, making the battery cells prone to cracking and reducing the reliability of the battery cells.

[0082] In view of this, an embodiment of the present application provides a battery cell, in which a support member is provided in the insulating member of the battery cell. Even if the electrode assembly moves toward the direction of the pressure relief mechanism under the drive of high-temperature and high-pressure materials, the support member can limit the deformation of the insulating member, reduce the distance moved by the electrode assembly, and make it difficult for the electrode assembly to move to a position that blocks the pressure relief mechanism, thereby maintaining the patency of the discharge channel, which is conducive to increasing the discharge speed of the high-temperature and high-pressure materials inside the battery cell and improving the reliability of the battery cell.

[0083] The technical solutions described in the embodiments of the present application are applicable to various battery-powered electrical devices. Electrical devices may be vehicles, mobile phones, portable devices, laptop computers, ships, spacecraft, electric toys, and electric tools, etc. Vehicles may be fuel vehicles, gas vehicles, or new energy vehicles. New energy vehicles may be pure electric vehicles, hybrid vehicles, or extended-range vehicles, etc. Spacecraft include airplanes, rockets, space shuttles, and spacecraft, etc. Electric toys include fixed or mobile electric toys, such as game consoles, electric car toys, electric ship toys, and electric airplane toys, etc. Electric tools include metal cutting electric tools, grinding electric tools, assembly electric tools, and railway electric tools, such as electric drills, electric grinders, electric wrenches, electric screwdrivers, electric hammers, impact drills, concrete vibrators, and electric planers, etc. The embodiments of the present application include but are not limited to the above-mentioned electrical devices.

[0084] For the convenience of description, the following embodiments are described by taking a vehicle as an example of an electrical device.

[0085] As shown in Figure 1, it is a structural schematic diagram of a vehicle 1 according to an embodiment of the present application. The vehicle 1 can be a fuel vehicle, a gas vehicle or a new energy vehicle. The new energy vehicle can be a pure electric vehicle, a hybrid vehicle or an extended-range vehicle, etc. A motor 90, a controller 80 and a battery 10 can be provided inside the vehicle 1. The controller 80 is used to control the battery 10 to supply power to the motor 90. For example, a battery 10 can be provided at the bottom, front or rear of the vehicle 1. The battery 10 can be used to power the vehicle 1. For example, the battery 10 can be used as an operating power source for the vehicle 1, for the circuit system of the vehicle 1, for example, for the working power requirements of the vehicle 1 during startup, navigation and operation. In another embodiment of the present application, the battery 10 can not only serve as an operating power source for the vehicle 1, but also as a driving power source for the vehicle 1, replacing or partially replacing fuel or natural gas to provide driving power for the vehicle 1.

[0086] To meet different power requirements, a battery can include multiple battery cells, which can be connected in series, parallel, or in a hybrid configuration. A hybrid configuration refers to a combination of series and parallel connections. A battery can also be referred to as a battery pack. Alternatively, multiple battery cells can be connected in series, parallel, or in a hybrid configuration to form a battery module, which can then be connected in series, parallel, or in a hybrid configuration to form a battery. In other words, multiple battery cells can be directly connected to form a battery, or they can be first connected to form battery modules, which can then be connected to form a battery.

[0087] For example, FIG2 shows a schematic structural diagram of a battery 10 according to an embodiment of the present application. The battery 10 may include at least one battery module 200. The battery module 200 includes a plurality of battery cells 20. The battery 10 may also include a housing 11 having a hollow interior and housing the plurality of battery cells 20. FIG2 shows a possible implementation of the housing 11 according to an embodiment of the present application. As shown in FIG2 , the housing 11 may include two parts, referred to herein as a first part 111 and a second part 112, which are snap-fitted together. The shapes of the first part 111 and the second part 112 may be determined based on the shape of the battery module 200 assembly. At least one of the first part 111 and the second part 112 may have an opening. For example, as shown in FIG2 , the first part 111 and the second part 112 may each be a hollow cuboid with only one open face. The opening of the first part 111 and the opening of the second part 112 are arranged opposite each other, and the first part 111 and the second part 112 snap-fit ​​together to form the housing 11 having a closed chamber.

[0088] For another example, unlike that shown in Figure 2, only one of the first portion 111 and the second portion 112 may be a hollow rectangular parallelepiped with an opening, while the other may be a plate-shaped structure to cover the opening. For example, assuming that the second portion 112 is a hollow rectangular parallelepiped with only one open face, and the first portion 111 is a plate-shaped structure, the first portion 111 covers the opening of the second portion 112 to form a case 11 having a closed chamber, which can be used to accommodate multiple battery cells 20. The multiple battery cells 20 are connected in parallel, series, or in a mixed combination and then placed in the case 11 formed by the first portion 111 and the second portion 112 being fastened together.

[0089] Optionally, the battery 10 may also include other structures, which will not be described in detail here. For example, the battery 10 may also include a busbar component, which is used to achieve electrical connection between multiple battery cells 20, such as parallel connection, series connection, or mixed connection. Specifically, the busbar component can achieve electrical connection between the battery cells 20 by connecting the electrode terminals of the battery cells 20. Furthermore, the busbar component can be fixed to the electrode terminals of the battery cells 20 by welding. The electrical energy of the multiple battery cells 20 can be further led out through the conductive structure through the box body 11.

[0090] Depending on different power requirements, the number of battery cells 20 in the battery module 200 can be set to any value. Multiple battery cells 20 can be connected in series, parallel, or in a mixed manner to achieve a larger capacity or power. Since the number of battery cells 20 included in each battery 10 may be large, for ease of installation, the battery cells 20 are grouped and each group of battery cells 20 constitutes a battery module 200. The number of battery cells 20 included in the battery module 200 is not limited and can be set according to requirements. The battery 10 may include multiple battery modules 200, which can be connected in series, parallel, or in a mixed manner.

[0091] FIG3 shows a schematic diagram of the exploded structure of a battery cell 20 provided in an embodiment of the present application. As shown in FIG3 , the battery cell 20 includes a housing 21, an electrode assembly 22, an insulating member 23, and a support member 24. The housing 21 has a first wall 211, on which a pressure relief mechanism 213 is provided. The electrode assembly 22 is accommodated in the housing 21. The insulating member 23 is disposed between the electrode assembly 22 and the first wall 211. The insulating member 23 has a receiving cavity 26. The insulating member 23 has an exhaust passage connecting the pressure relief mechanism 213 and the electrode assembly 22. The support member 24 is accommodated in the receiving cavity 26 to limit deformation of the exhaust passage.

[0092] The battery cell 20 may include a housing 21 and one or more electrode assemblies 22. The housing 21 may have multiple walls, with the first wall 211 representing one or more of the walls of the housing 21. The housing 21 of the battery cell 20 may be shaped according to the combined shape of the one or more electrode assemblies 22. For example, the housing 21 may be a rectangular parallelepiped, a cube, or a cylinder. The housing 21 may include the first wall 211 and a shell 212. The shell 212 may be a hollow structure. For example, the shell 212 may be a hollow rectangular parallelepiped, a cube, or a cylinder, with one of its faces having an opening to allow the one or more electrode assemblies 22 to be placed within the shell 212. For example, when the shell 212 is a hollow rectangular parallelepiped or a cube, one of the planes of the shell 212 is an open face, meaning that the plane has no walls, allowing the inside and outside of the shell 212 to communicate. When the shell 212 is a hollow cylinder, the end faces of the shell 212 are open faces, meaning that the end faces have no walls, allowing the inside and outside of the shell 212 to communicate. The first wall 211 covers the opening and is connected to the housing 212 to form a closed cavity for accommodating the electrode assembly 22. The housing 212 is filled with an electrolyte, such as an electrolyte solution.

[0093] A pressure relief mechanism 213 is provided on the first wall 211. This mechanism can be activated when the temperature and / or pressure inside the battery cell 20 reaches a threshold, thereby releasing the temperature and / or pressure inside the battery cell 20. "Activation," as used in the embodiments of this application, refers to the pressure relief mechanism 213 being activated or set to a certain state, thereby releasing the internal pressure and temperature of the battery cell 20. The action of the pressure relief mechanism 213 may include, but is not limited to, rupturing, breaking, tearing, or opening at least a portion of the pressure relief mechanism 213. When the pressure relief mechanism 213 is activated, high-temperature, high-pressure substances within the battery cell 20 are discharged from the activated portion as emissions. This method allows pressure and temperature relief from the battery cell 20 under controllable pressure or temperature, thereby reducing the possibility of accidents. Emissions from the battery cell 20, as used in the embodiments of this application, include, but are not limited to, electrolyte, dissolved or split positive and negative electrode plates, separator fragments, high-temperature, high-pressure gases generated by the reaction, and flames.

[0094] The electrode assembly 22 is a component in the battery cell 20 where the electrochemical reaction occurs. The electrode assembly 22 can be a cylinder, a cuboid, etc. If the electrode assembly 22 is a cylindrical structure, the shell 212 can also be a cylindrical structure. If the electrode assembly 22 is a cuboid structure, the shell 212 can also be a cuboid structure. For ease of explanation, the embodiment of the present application takes the shell 212 as an example. For any electrode assembly 22, the electrode assembly 22 can include at least two tabs, and the at least two tabs can include at least one positive electrode tab and at least one negative electrode tab. The positive electrode tab can be formed by stacking the portion of the positive electrode sheet that is not coated with the positive electrode active material layer, and the negative electrode tab can be formed by stacking the portion of the negative electrode sheet that is not coated with the negative electrode active material layer.

[0095] The insulating member 23 is disposed between the electrode assembly 22 and the first wall 211 to insulate the electrode assembly 22 from the first wall 211 and reduce the possibility of the first wall 211 becoming electrically charged. Alternatively, the insulating member 23 may be made of polypropylene (PP), polyphenylene sulfide (PPS), or soluble polytetrafluoroethylene (PFA). Figure 4 illustrates a schematic structural diagram of the first wall 211, the insulating member 23, and the support member 24. As shown in Figure 4, the insulating member 23 may include recessed spaces relative to the main body of the insulating member 23, forming a receiving cavity 26 for the insulating member 23. The insulating member 23 includes a discharge channel connecting the pressure relief mechanism 213 and the electrode assembly 22. The discharge channel refers to the path for high-temperature, high-pressure substances to travel from the battery cell 20 to the pressure relief mechanism 213 when generated within the battery cell 20. In some embodiments, the high-temperature, high-pressure substances may be generated in the region where the electrode assembly 22 is located. The discharge channel can also be understood as connecting the region within the battery cell 20 where the electrode assembly 22 is located with the region where the pressure relief mechanism 213 is located.

[0096] The support member 24 is disposed in the accommodating cavity 26 of the insulating member 23. As shown in FIG5 , in some embodiments, at least a portion of the support member 24 is accommodated in the accommodating cavity 26. In some embodiments, the support member 24 may be made of a different material from the insulating member 23. For example, the hardness, melting point and other properties of the material of the support member 24 may be different from those of the material of the insulating member 23. Specifically, the material of the support member 24 may be a high-temperature resistant material. That is, when the battery cell 20 experiences thermal runaway, the support member 24 will not be melted by the high-temperature substance generated by the thermal runaway. Optionally, the material of the support member 24 may include at least one hard material selected from metal, graphite, polytetrafluoroethylene, mica or ceramics.

[0097] In one possible embodiment, the support member 24 may be fixedly connected to the insulating member 23. For example, the support member 24 may be bonded to the surface of the insulating member 23. In another possible embodiment, the support member 24 may be accommodated in the accommodating cavity 26 by means of an interference fit, thereby reducing the possibility of the support member 24 falling out of the accommodating cavity 26.

[0098] In the event of thermal runaway inside the battery cell 20, the support member 24 can limit the deformation of the exhaust channel and keep the exhaust channel unobstructed, so that the high-temperature and high-pressure substances generated by the thermal runaway can reach the pressure relief mechanism 213 along the exhaust channel, causing the pressure relief mechanism 213 to be actuated. In an embodiment of the present application, the support member can limit the deformation of the exhaust channel formed by the insulating member, wherein the deformation of the exhaust channel refers to deformation that exceeds the elastic range of the insulating member itself, and limiting the deformation of the exhaust channel refers to reducing the degree of deformation of the exhaust channel. In other words, the embodiment of the present application allows the exhaust channel to deform within its own elastic range. Compared with the case where no support member is provided on the insulating member, the support member can reduce the deformation of the exhaust channel formed by the insulating member under the action of external force to a greater extent, so that the exhaust channel is not easily deformed to the extent that it cannot discharge the high-temperature and high-pressure substances to the pressure relief mechanism.

[0099] For illustration, Figure 6 illustrates a possible discharge path for high-temperature, high-pressure materials generated by thermal runaway within a battery cell 20, as well as a simplified structural diagram of the changes that occur within the electrode assembly 22 under the influence of these materials. As shown in Figure 6(a), when a small amount of high-temperature, high-pressure materials are generated within the battery cell 20, these materials can accumulate near the pressure relief mechanism 213 through the discharge channel within the battery cell 20, causing the pressure relief mechanism 213 to activate and discharge the materials within the battery cell 20. As shown in Figure 6(b), when a large amount of high-temperature, high-pressure materials is generated within the battery cell 20 without a support member 24, the electrode assembly 22 will move toward the pressure relief mechanism 213 under the influence of these materials. However, the insulating member 23 is susceptible to melting and softening under the influence of these materials. As the electrode assembly 22 moves further toward the pressure relief mechanism 213, the melted and softened insulating member 23 will also deform as the electrode assembly 22 moves, resulting in blockage of the discharge channel. On the one hand, high-temperature, high-pressure substances cannot pass through the discharge channel to reach the pressure relief mechanism 213, and the temperature or pressure in the area surrounding the pressure relief mechanism 213 does not reach the activation threshold, preventing the pressure relief mechanism 213 from actuating. On the other hand, the electrode assembly 22, driven by the high-temperature, high-pressure substances, may further block the pressure relief mechanism 213, also preventing the pressure relief mechanism 213 from actuating properly. Accumulation of high-temperature, high-pressure substances within the battery cell 20 to a certain extent can easily cause an explosion. As shown in FIG6(c), the battery cell 20 provided in the embodiment of the present application is provided with a support member 24. In the event of a large amount of high-temperature, high-pressure substances generated within the battery cell 20, even if the insulating member 23 melts and softens under the action of the high-temperature substances, the support member 24 can limit deformation of the discharge channel on the insulating member 23, maintaining the patency of the discharge channel as much as possible in the event of movement of the electrode assembly 22, allowing the high-temperature, high-pressure substances to reach the pressure relief mechanism 213. Furthermore, the support member 24 can limit further movement of the electrode assembly 22, reducing the possibility of the pressure relief mechanism 213 being directly blocked by the electrode assembly 22, thereby maintaining the patency of the discharge channel.

[0100] The battery cell 20 provided in the embodiment of the present application can limit the deformation of the discharge channel through the support member 24 when thermal runaway occurs inside the battery cell 20, reducing the possibility of the discharge channel or the pressure relief structure being blocked by the electrode assembly 22, which is conducive to the actuation of the pressure relief mechanism 213 to quickly discharge high-temperature and high-pressure substances inside the battery cell 20, thereby improving the reliability of the battery cell 20.

[0101] According to some embodiments of the present application, optionally, the insulating member 23 includes a first insulating wall 231 , and an accommodating cavity 26 is formed between the first insulating wall 231 and the first wall 211 .

[0102] 7 , the first insulating wall 231 is located on a surface of the insulating member 23 facing the battery assembly along the thickness direction Z of the first wall 211 . Specifically, the first insulating wall 231 may be a thin sheet-like structure perpendicular to the thickness direction Z of the first wall 211 .

[0103] A gap is formed between the first insulating wall 231 and the first wall 211, specifically, a gap is formed in the thickness direction Z of the first wall 211. The thickness direction Z of the first wall 211 may be the thickness direction Z of the insulating member 23, and is perpendicular to the length direction X and the width direction Y of the first wall 211. This gap is used to form an accommodating cavity 26 for accommodating the support member 24.

[0104] As shown in FIG7 , the support member 24 is accommodated in the accommodation cavity formed between the first insulating wall 231 and the first wall 211 , and the first insulating wall 231 provides support for the support member 24 on the side of the support member 24 facing the electrode assembly 22 along the thickness direction Z of the first wall 211 .

[0105] The first insulating wall 231 can provide support for the support member 24, reduce the possibility of the support member 24 falling from the accommodating cavity 26, and help maintain the position of the support member 24 relative to the insulating member 23, thereby improving the effect of the support member 24 in limiting the deformation of the exhaust channel.

[0106] According to some embodiments of the present application, optionally, a projection of the first insulating wall 231 in the thickness direction Z of the first wall 211 covers a projection of the support member 24 in the thickness direction Z of the first wall 211 .

[0107] In one possible embodiment, the support member 24 is disposed in the accommodating cavity 26. Along the thickness direction Z of the first wall 211, one side of the support member 24 contacts the first wall 211, and the other side contacts the first insulating wall 231. In the thickness direction Z of the first wall 211, the projection of the first insulating wall 231 overlaps the projection of the support member 24. Thus, the first insulating wall 231 can insulate the support member 24 from the electrode assembly 22 in the thickness direction Z of the first wall 211. Regardless of whether the support member 24 itself is made of an insulating material, the first insulating wall 231 can improve the insulation performance between the electrode assembly 22 and the support member 24.

[0108] This can ensure better insulation performance between the electrode assembly 22 and the first wall 211, reduce the possibility of the first wall 211 being charged due to contact between the electrode assembly 22 and the support member 24, or between the support member 24 and the first wall 211, and help improve the reliability of the battery cell 20.

[0109] According to some embodiments of the present application, optionally, the insulating member 23 includes a second insulating wall 232 , which is disposed between the first insulating wall 231 and the first wall 211 , and forms an accommodating cavity 26 with the first insulating wall 231 .

[0110] In the embodiment of the present application, the insulating member 23 may include a first insulating wall 231 and a second insulating wall 232. The second insulating wall 232 may be a thin sheet-like structure perpendicular to the thickness direction Z of the first wall 211. A certain gap is provided between the first insulating wall 231 and the second insulating wall 232, and the gap is the accommodating cavity 26 for accommodating the support member.

[0111] FIG8 shows a view of the structure in FIG7 along the thickness direction Z of the first wall 211 , and FIG9 is a possible cross-sectional view of the structure in FIG8 along the AA direction.

[0112] As shown in Figures 8 and 9, the second insulating wall 232 can be the portion of the insulating member 23 that is in direct contact with the first wall 211. Optionally, the second insulating wall 232 can be fixedly connected to the first wall 211. A receiving cavity 26 is formed between the second insulating wall 232 and the first insulating wall 231, and the support member 24 is received in the receiving cavity 26. Portions of the first wall 211 that are not provided with components with certain functions can be covered by the second insulating wall 232, wherein the components with certain functions on the first wall 211 can be, for example, components for electrically connecting the electrode terminal 214 and the electrode assembly 22, injection holes, etc. The second insulating wall 232 shown in Figures 8 and 9 covers the surface of the first wall 211 facing the electrode assembly 22 as much as possible, which can improve the insulation performance of the insulating member 23.

[0113] FIG10 is another possible cross-sectional view of the structure in FIG8 along the AA direction, and FIG11 is an axonometric view corresponding to the structure shown in FIG10.

[0114] As shown in Figures 10 and 11, the second insulating wall 232 can also be a portion of the insulating member 23 that is in direct contact with the first wall 211. The second insulating wall 232 can be located only in the area where the support member 24 is located, isolating the support member 24 from the first wall 211. The support member 24 is accommodated in the accommodating cavity 26 formed between the second insulating wall 232 and the first insulating wall 231. In one possible embodiment, in the thickness direction Z of the first wall 211, the projection of the second insulating wall 232 can cover the projection of the support member 24. The second insulating wall 232 shown in Figures 10 and 11 can reduce the weight of the insulating member 23 and reduce the manufacturing cost of the insulating member 23 while satisfying the insulation performance between the first wall 211 and the electrode assembly 22.

[0115] The second insulating wall 232 can isolate the support member 24 from the first wall 211, thereby improving the insulation performance between the support member 24 and the first wall 211. At the same time, the accommodating cavity 26 formed by the second insulating wall 232 and the first insulating wall 231 can provide a more stable accommodating space for the support member 24, making the support member 24 less likely to fall during the assembly process.

[0116] According to some embodiments of the present application, optionally, the insulating member 23 includes a second insulating wall 232, which is arranged on the surface of the insulating member 23 facing the first wall 211 in the thickness direction Z of the first wall 211, and a accommodating cavity 26 is formed between the second insulating wall 232 and the surface of the insulating member 23 facing the electrode assembly 22 in the thickness direction Z of the first wall 211.

[0117] Figure 12 is another possible cross-sectional view of the structure in Figure 8 along the AA direction. As shown in Figure 12, the second insulating wall 232 is provided on the surface of the insulating member 23 facing the first wall 211 in the thickness direction Z of the first wall 211. Optionally, the second insulating wall 232 may be connected to the first wall 211. In the embodiment shown in Figure 12, the insulating member 23 may include the second insulating wall 232 but not the first insulating wall 231. In one possible implementation, all portions of the first wall 211 not provided with functional components may be covered by the second insulating wall 232; alternatively, the second insulating wall 232 may be located only in the area where the support member 24 is located, isolating the support member 24 from the first wall 211.

[0118] An accommodation cavity 26 may be formed between the second insulating wall 232 and a surface of the insulating member 23 facing the electrode assembly 22 in the thickness direction Z of the first wall 211 , and the support member 24 is accommodated in the accommodation cavity 26 .

[0119] The second insulating wall 232 can separate the support member 24 from the first wall 211 and play an insulating role between the support member 24 and the first wall 211 , so that the first wall 211 is not easily charged, thereby improving the reliability of the battery cell 20 .

[0120] According to some embodiments of the present application, optionally, the insulating member 23 includes a connecting wall 233 , the connecting wall 233 connecting the first insulating wall 231 and the second insulating wall 232 , and the connecting wall 233 extends along the thickness direction Z of the first wall 211 .

[0121] As shown in Figures 7 to 12, in one possible embodiment, the connecting wall 233 can extend along the thickness direction Z of the first wall 211 and the width direction Y of the first wall 211 to provide support for the gap between the first insulating wall 231 and the second insulating wall 232. Optionally, the connecting wall 233 can be provided at the edge of the insulating member 23 or in the middle area of ​​the insulating member 23 to enhance the anti-deformation strength of the corresponding area of ​​the insulating member 23.

[0122] In another possible embodiment, the connecting wall 233 may extend along the thickness direction Z of the first wall 211 and the length direction X of the first wall 211. The connecting wall 233 is provided at the edge of the insulating member 23, and can provide support for the gap between the first insulating wall 231 and the second insulating wall 232. It can also form an accommodating cavity 26 for accommodating the support member 24 together with the first insulating wall 231 and the second insulating wall 232. In this case, the connecting wall 233 can provide support for the support member 24 in the width direction Y of the first wall 211.

[0123] In another possible embodiment, connecting walls 233 may be provided on the edges of the insulating member 23 in both the length direction X and the width direction Y of the first wall 211 to improve the overall strength and stability of the insulating member 23. Optionally, a connecting wall 233 may also be provided in the middle region of the insulating member 23 to enhance the anti-deformation strength of the middle region of the insulating member 23.

[0124] The connecting wall 233 can improve the anti-deformation strength of the insulating member 23 in the thickness direction Z of the first wall 211 , and provide support for the supporting member 24 accommodated in the accommodating cavity 26 , so that the supporting member 24 is not easily dropped.

[0125] According to some embodiments of the present application, optionally, a discharge hole 234 is provided on the connecting wall 233 and penetrates the connecting wall 233 in the thickness direction Z of the connecting wall 233 .

[0126] The connecting wall 233 is a structure on the insulating member 23 that connects the first insulating wall 231 and the second insulating wall 232. A drain hole 234 extends through the connecting wall 233 in the thickness direction Z. High-temperature, high-pressure substances generated within the battery cell 20 can escape through the drain hole 234 into the gap between the first and second connecting walls 233. The drain hole 234 and this gap form a drain channel. Especially when the connecting wall 233 is positioned around the pressure relief mechanism 213, the drain hole 234 helps guide the high-temperature, high-pressure substances toward the location of the pressure relief mechanism 213, thereby activating the pressure relief mechanism 213.

[0127] In one possible embodiment, a drain hole 234 is provided on a connecting wall 233 of the insulating member 23 that extends along the thickness direction Z of the first wall 211 and the width direction Y of the first wall 211, as shown in Figures 7 to 9. Optionally, a drain hole 234 may also be provided on the connecting wall 233 of the insulating member 23 that extends along the thickness direction Z of the first wall 211 and the length direction X of the first wall 211.

[0128] The discharge hole 234 on the connecting wall 233 can form a discharge channel together with the accommodating cavity 26, guiding the high-temperature and high-pressure material to flow toward the pressure relief mechanism 213, which is conducive to the actuation of the pressure relief structure to quickly discharge the high-temperature and high-pressure material inside the battery cell, thereby improving the reliability of the battery cell 20.

[0129] According to some embodiments of the present application, optionally, the connecting wall 233 includes a first connecting portion 2331, the first connecting portion 2331 is arranged on both sides of the pressure relief mechanism 213 in the length direction X of the first wall 211, and the discharge hole 234 includes a first through hole 2341, the first through hole 2341 passes through the first connecting portion 2331 in the length direction X of the first wall 211, and the first through hole 2341 is used to form a discharge channel.

[0130] As shown in Figures 7 to 12 , the first connection portion 2331 refers to the portion of the connecting wall 233 disposed on both sides of the pressure relief mechanism 213 in the length direction X of the first wall 211. In some embodiments, the pressure relief mechanism 213 may be disposed in the middle region of the first wall 211. In this case, the first connection portion 2331 may be disposed in the middle region of the insulating member 23, corresponding to the position of the pressure relief mechanism 213.

[0131] The first through hole 2341 refers to the discharge hole 234 arranged on the first connecting portion 2331 in the discharge hole 234. The first through hole 2341 penetrates the first connecting portion 2331 in the length direction X of the first wall 211. The first connecting portion 2331 is arranged along the length direction X of the first wall 211. The first through hole 2341 can connect the area where the pressure relief mechanism 213 is located with the area where the accommodating chamber 26 is located, forming at least a part of the discharge channel.

[0132] The first connection portion 2331 and the first through hole 2341 can form a discharge channel in the surrounding area of ​​the pressure relief mechanism 213, which is beneficial for guiding the high-temperature and high-pressure substances generated by thermal runaway to flow to the area of ​​the pressure relief mechanism 213 when thermal runaway occurs inside the battery cell 20, so that the pressure relief mechanism 213 can be actuated in time, thereby improving the reliability of the battery cell 20.

[0133] According to some embodiments of the present application, optionally, the insulating member 23 has a second through hole 236 that penetrates the insulating member 23 in the thickness direction Z of the first wall 211 , and the second through hole 236 is arranged opposite to the pressure relief mechanism 213 , and the second through hole 236 is used to form a discharge channel.

[0134] As shown in Figures 7 to 12, the second through hole 236 penetrates the insulating member 23 in the thickness direction Z of the first wall 211. In one possible embodiment, the insulating member 23 includes a first insulating wall 231 or a second insulating wall 232, and the second through hole 236 can penetrate the first insulating wall 231 or the second insulating wall 232 in the thickness direction Z of the first wall 211. Alternatively, if the insulating member 23 includes a first insulating wall 231 and a second insulating wall 232, the second through hole 236 can penetrate both the first insulating wall 231 and the second insulating wall 232. The second through hole 236 is disposed opposite the pressure relief mechanism 213. The second through hole 236 can connect the area where the pressure relief mechanism 213 is located with the area of ​​the electrode assembly 22 at a position opposite the pressure relief mechanism 213, thereby forming at least a portion of the exhaust channel.

[0135] The second through hole 236 can more directly connect the pressure relief mechanism 213 and the electrode assembly 22, so that the high-temperature and high-pressure material inside the battery cell 20 can flow to the pressure relief mechanism 213 more quickly, so that the pressure relief mechanism 213 can be actuated in time, thereby improving the reliability of the battery cell 20.

[0136] According to some embodiments of the present application, optionally, the support member 24 is disposed on an edge of the insulating member 23 on a plane perpendicular to the thickness direction Z of the first wall 211 .

[0137] As shown in Figures 13 to 15, Figure 13 is a schematic diagram of the decomposed structure of the structure shown in Figure 7, Figure 14 is a schematic diagram of the structure of another first wall, insulating member and supporting member, and Figure 15 is a schematic diagram of the decomposed structure of the structure shown in Figure 14.

[0138] The support member 24 can be disposed at an edge of the insulating member 23 on a plane perpendicular to the thickness direction Z of the first wall 211. Specifically, on this plane, the insulating member 23 can be approximately rectangular, and the support member 24 can be located on the long side or the wide side of the rectangle. For example, Figures 13 to 15 illustrate a case where the support member 24 is disposed on the long side of the rectangle, extending along the length direction X of the first wall 211. Similarly, the support member 24 can extend along the width direction Y of the first wall 211 and be disposed on the wide side of the rectangle.

[0139] The support member 24 is disposed at the edge of the insulating member 23 and is not likely to interfere with other components in the battery cell 20 , which is beneficial to improving the qualified rate of the battery cell 20 .

[0140] According to some embodiments of the present application, optionally, the support member 24 is located at an edge of the insulating member 23 in the width direction Y of the first wall 211 .

[0141] The edge of the insulating member 23 in the width direction Y of the first wall 211 refers to the long side of the insulating member 23 , that is, the side of the insulating member 23 extending along the length direction X of the first wall 211 .

[0142] In some embodiments, the support member 24 may extend from one end to the other end of the long side of the insulating member 23 ; alternatively, the support member 24 may be provided only on a portion of the long side of the insulating member 23 .

[0143] The support member 24 is arranged along the longer side of the insulating member 23 so that the support member 24 can play a certain supporting role for the insulating member 23 and the electrode assembly 22 in a larger range, thereby limiting the deformation of the exhaust passage.

[0144] According to some embodiments of the present application, optionally, the support members 24 are arranged at intervals along the length direction X of the first wall 211 .

[0145] As shown in FIG. 13 , the support members 24 may extend along the length direction X of the first wall 211 and be spaced apart in the length direction X of the first wall 211 , which can reduce the overall weight of the battery cell 20 while limiting deformation of the exhaust passage.

[0146] Alternatively, taking FIG. 13 as an example, FIG. 13 shows that two support members 24 are provided in the length direction X of the first wall 211, and the gap between the two support members 24 is located in the surrounding area of ​​the pressure relief mechanism 213. This provides more space for the high-temperature and high-pressure material to move toward the pressure relief mechanism 213, which helps guide the high-temperature and high-pressure material to move toward the pressure relief mechanism 213.

[0147] According to some embodiments of the present application, optionally, the support member 24 is located at an edge of the insulating member 23 in the length direction X of the first wall 211 .

[0148] The edge of the insulating member 23 in the length direction X of the first wall 211 refers to the wide side of the insulating member 23, that is, the edge of the insulating member 23 extending along the width direction Y of the first wall 211. As shown in Figure 16, the support member 24 can extend along the width direction Y of the first wall 211. Optionally, the support members 24 can be arranged at intervals along the width direction Y of the first wall 211.

[0149] In some embodiments, the support member 24 may be disposed on edges of the insulating member 23 in both the length direction X and the width direction Y of the first wall 211 .

[0150] The support member 24 is arranged on the wide side of the insulating member 23 to limit the deformation of the insulating member 23 at the corresponding position of the insulating member 23, and at the same time limit the movement of the electrode assembly 22 toward the pressure relief mechanism 213 to a certain extent, thereby reducing the probability of the electrode assembly 22 blocking the pressure relief mechanism 213 and keeping the discharge channel unobstructed.

[0151] According to some embodiments of the present application, optionally, the support member 24 is disposed in a surrounding area of ​​the pressure relief mechanism 213 .

[0152] Figure 17 illustrates a case where the support member 24 extends along the width direction Y of the first wall 211 and is disposed on at least one side of the pressure relief mechanism 213 in the length direction X of the first wall 211. Alternatively, the support member 24 may extend along the length direction X of the first wall 211 and be disposed on at least one side of the pressure relief mechanism 213 in the width direction Y of the first wall 211. Alternatively, the support member 24 may be disposed opposite the pressure relief mechanism 213 in the thickness direction Z of the first wall 211.

[0153] The support member 24 disposed around the pressure relief mechanism 213 can more directly restrict further movement of the electrode assembly 22 near the pressure relief mechanism 213 toward the pressure relief mechanism 213, thereby limiting deformation of the discharge channel near the pressure relief mechanism 213. High-temperature, high-pressure substances within the battery cell 20 can reach the pressure relief mechanism 213 through the discharge channel, allowing the pressure relief mechanism 213 to be actuated to discharge the high-temperature, high-pressure substances within the battery cell 20, thereby improving the reliability of the battery cell 20.

[0154] According to some embodiments of the present application, optionally, a plurality of support members 24 enclose a surrounding area of ​​the pressure relief mechanism 213 to form an accommodation space, and the pressure relief mechanism 213 is disposed in the accommodation space.

[0155] In some embodiments, support members 24 may be provided around the pressure relief mechanism 213. For example, support members 24 may be provided on both sides of the pressure relief mechanism 213 in the length direction X and the width direction Y of the first wall 211. In this case, multiple support members 24 can enclose a certain accommodation space, enclosing the pressure relief mechanism 213 in the middle, that is, the pressure relief mechanism 213 is located in the accommodation space.

[0156] The plurality of support members 24 provided around the pressure relief mechanism 213 can further limit the deformation of the structure around the pressure relief mechanism 213 and keep the discharge channel around the pressure relief mechanism 213 unobstructed.

[0157] According to some embodiments of the present application, optionally, the support member 24 is provided with a third through hole 241 , and the third through hole 241 is used to form a discharge channel.

[0158] The third through hole 241 may be in communication with the accommodating cavity 26 , and optionally, may be in communication with the electrode assembly 22 and the area where it is located, and optionally, may be in communication with the pressure relief mechanism 213 and the area where it is located.

[0159] In one possible embodiment, the third through hole 241 may penetrate the support member 24 along a certain direction. For example, if the support member 24 extends along the width direction Y of the first wall 211, the third through hole 241 may penetrate the support member 24 along the length direction X of the first wall 211. Alternatively, if the support member 24 extends along the length direction X of the first wall 211, the third through hole 241 may penetrate the support member 24 along the width direction Y of the first wall 211. In another possible embodiment, the third through hole 241 may form channels on the support structure from two intersecting directions. For example, the openings of the third through hole 241 on the surface of the support member 24 may be located on the intersecting surfaces of the support member 24, and these openings may be interconnected within the support member 24.

[0160] In one possible embodiment, the third through hole 241 may be disposed opposite to a through hole provided on the insulating member 23. Specifically, the third through hole 241 may be connected to the through hole provided on the insulating member 23, thereby forming at least a portion of the drain passage. For example, the third through hole 241 may be connected to the drain hole 234, specifically, the drain hole 234 provided on the edge of the insulating member 23. Alternatively, the third through hole 241 may be connected to the first through hole 2341. Alternatively, the third through hole 241 may be connected to the second through hole 236.

[0161] The third through hole 241 penetrates the support structure, forming at least a portion of the exhaust passage. High-temperature, high-pressure substances within the battery cell 20 can pass through the third through hole 241. In some embodiments, the path of the third through hole 241 can be designed to guide the high-temperature, high-pressure substances within the battery cell 20 to flow in a specific direction.

[0162] The third through hole 241 can provide a path for the high-temperature and high-pressure material to flow inside the battery cell 20 , which is beneficial to the discharge of the high-temperature and high-pressure material, so that the pressure relief mechanism 213 can be actuated in time, thereby improving the reliability of the battery cell 20 .

[0163] According to some embodiments of the present application, optionally, the support member 24 includes an elongated main body.

[0164] The support member 24 provided in the embodiments of the present application includes a long, rectangular main body portion, which refers to the portion of the support member 24 extending in a certain direction. In some embodiments, the support member 24 may extend from one end of the accommodating cavity 26 to the other along the length direction X of the first wall 211. Alternatively, the main body portion may be a columnar structure, such as a cylinder or prism. In some embodiments, the support member 24 may also include structures such as protrusions or grooves.

[0165] The main body is in an elongated shape, which can limit the movement of the electrode assembly 22 within a larger range without affecting the discharge capacity of the discharge channel, thereby keeping the discharge channel unobstructed, reducing the possibility of deformation of the discharge channel resulting in the inability to discharge high-temperature and high-pressure materials, and improving the reliability of the battery cell 20.

[0166] According to some embodiments of the present application, optionally, the melting point of the support member 24 is higher than the melting point of the insulating member 23 .

[0167] In the later stages of thermal runaway, the electrode assembly 22 may be driven by the high-temperature, high-pressure material to move toward the first wall 211, and may even come into contact with the insulating member 23. The insulating member 23 melts and softens under the action of the high-temperature, high-pressure material, and is prone to deformation as the electrode assembly 22 moves further toward the first wall 211, blocking the original discharge channel and preventing the high-temperature, high-pressure material from passing through the discharge channel to the pressure relief mechanism 213. In the embodiment of the present application, the melting point of the support member 24 is higher than that of the insulating member 23. Therefore, under the same temperature environment, the support member 24 is less likely to melt or dissolve than the insulating member 23, and can maintain its original shape and position within the accommodating cavity 26, providing support for the electrode assembly 22 moving toward the pressure relief mechanism 213. This makes it difficult for the electrode assembly 22 to move to a position that blocks the discharge channel, thereby limiting deformation of the discharge channel and providing a discharge channel for the high-temperature, high-pressure material to reach the pressure relief mechanism 213, which is beneficial for improving the reliability of the battery cell 20.

[0168] According to some embodiments of the present application, optionally, the melting point of the support member 24 is greater than 100°C.

[0169] In one example, the material of the support member 24 can be a single material, for example, the material of the support member 24 is a single material such as aluminum or copper. In this case, the support member 24 has a fixed melting point.

[0170] In another example, the material of the support member 24 can be a composite material. For example, the support member 24 can be a mixture of aluminum and copper. In this case, the support member 24 does not have a fixed melting point, that is, the melting point of the support member 24 is within the melting point range of various materials. For example, the melting point of aluminum is 660°C and the melting point of copper is 1083°C. Then, the melting point range of the support member 24 is 660°C to 1083°C. Since the melting point of the support member 24 is higher than the melting point of the insulating member 23, it can be understood that the lowest melting point in the melting point range of the support member 24 is higher than the melting point of the insulating member 23.

[0171] For example, if the positive electrode material of battery cell 20 is a compound with an olivine structure, the melting point of support member 24 can be greater than 150°C, allowing thermal runaway gas to reach pressure relief mechanism 213 before pressure relief mechanism 213 opens. Furthermore, optionally, the melting point of support member 24 can be greater than 500°C, allowing battery cell 20 to maintain mechanical strength during thermal runaway. The compound with an olivine structure can be selected from lithium iron phosphate, lithium iron manganese phosphate, or a mixture of lithium iron phosphate and lithium iron manganese phosphate.

[0172] For another example, if the positive electrode material of the battery cell 20 contains a layered compound, the melting point of the support member 24 can be greater than 100°C, so that the thermal runaway gas can reach the pressure relief mechanism 213 smoothly before the pressure relief mechanism 213 opens the valve. Further optionally, the melting point of the support member 24 is greater than 400°C, which can enable the battery cell 20 to maintain mechanical strength during thermal runaway. Among them, the layered compound can be selected from lithium nickel cobalt manganese oxygen ternary layered material, or a mixture of lithium iron phosphate and lithium nickel cobalt manganese oxygen ternary layered material, or a mixture of lithium manganese iron and lithium nickel cobalt manganese oxygen ternary layered material.

[0173] Optionally, the support member 24 may be made of a high-temperature resistant material. For example, the support member 24 may be made of at least one hard material selected from metal, graphite, polytetrafluoroethylene, mica, ceramics, and the like.

[0174] In this embodiment, a support member 24 with a melting point greater than 100°C is used, which is advantageous in that it is not easily melted when thermal runaway occurs in the battery cell 20, thereby enabling a gas exhaust passage connected to the pressure relief mechanism 213 to be formed between the first wall 211 and the electrode assembly 22, so that the thermal runaway gas can be discharged to the outside of the battery cell 20 through the pressure relief mechanism 213 in a timely manner, thereby improving the reliability of the battery cell 20.

[0175] According to some embodiments of the present application, optionally, the first wall 211 is provided with an electrode terminal 214, the battery cell 20 includes a connecting member 25, the connecting member 25 is used to electrically connect the electrode terminal 214 and the electrode assembly 22, and the insulating member 23 has an avoidance hole 235 that passes through the insulating member 23 in the thickness direction Z of the first wall 211, and at least a portion of the connecting member 25 is accommodated in the avoidance hole 235.

[0176] Optionally, the battery cell 20 may further include electrode terminals 214. The first wall 211 is generally in the shape of a flat plate. The electrode terminals 214 are fixed to the flat surface of the first wall 211. The electrode terminals 214 include a positive electrode terminal 214a and a negative electrode terminal 214b. Each electrode terminal 214 is provided with a corresponding connecting member 25, or it may also be called a current collecting member, which is located between the first wall 211 and the electrode assembly 22 and is used to electrically connect the electrode assembly 22 and the electrode terminal 214. The positive electrode tabs of one or more electrode assemblies 22 are connected to the positive electrode terminal 214a via a connecting member 25, and the negative electrode tabs of one or more electrode assemblies 22 are connected to the negative electrode terminal 214b via another connecting member 25. In this battery cell 20, the electrode assembly 22 can be provided as a single or multiple electrode assemblies according to actual usage requirements.

[0177] The escape hole 235 extends through the insulating member 23 and is used to avoid the connecting member 25, allowing the connecting member 25 to achieve electrical connection with the electrode terminal 214 and the electrode assembly 22. As shown in Figures 13 to 17, in some embodiments, the escape hole 235 can have the same shape as the connecting member 25. In this case, the connecting member 25 can be entirely accommodated within the escape hole 235. Alternatively, the area occupied by the escape hole 235 can be larger than the area occupied by the connecting member 25 on the first wall 211. In this case, the connecting member 25 can also be entirely accommodated within the escape hole 235. Alternatively, the escape hole 235 can be provided only in the portion of the connecting member 25 that connects to the electrode terminal 214. In this case, the portion of the connecting member 25 that is intended for connection with the electrode terminal 214 is accommodated within the escape hole 235, while the remaining portion is accommodated within the accommodating cavity 26.

[0178] The avoidance hole 235 can provide space for the connection member 25 to electrically connect the electrode terminal 214 and the electrode assembly 22, so that the electric energy generated in the electrode assembly 22 can be led out of the battery cell 20 to provide electric energy to the electric device.

[0179] According to some embodiments of the present application, optionally, the support member 24 and the accommodating cavity 26 are interference fit.

[0180] Interference fit means that the size of the support member 24 in a certain direction is larger than the size of the accommodating cavity 26 in that direction. During the assembly process, the elasticity of the material of the insulating member 23 is utilized to cause the accommodating cavity 26 to expand and deform in that direction so as to accommodate the support member 24. After the accommodating cavity 26 recovers, it can generate force to fix the support member 24 in the accommodating cavity 26.

[0181] In one possible embodiment, the support member 24 may be interference-fitted with the accommodating cavity 26 in the longitudinal direction X of the first wall 211. The support member 24 may abut against the connecting wall 233 on the insulating member 23 in the longitudinal direction X of the first wall 211. Therefore, the dimension of the support member 24 in the longitudinal direction X of the first wall 211 may be slightly larger than the distance between two connecting walls 233 disposed opposite each other in the longitudinal direction X of the first wall 211. During assembly, an external force may be used to expand the dimension of the accommodating cavity 26 in the longitudinal direction X of the first wall 211. The support member 24 is then placed into the accommodating cavity 26. After the structure of the accommodating cavity 26 in the longitudinal direction X of the first wall 211 is restored, the support member 24 can be clamped in the longitudinal direction X of the first wall 211.

[0182] Optionally, the support member 24 may be interference fit with the accommodating cavity 26 in the thickness direction Z of the first wall 211. For example, if the insulating member 23 is provided with a first insulating wall 231, the first insulating wall 231 and the first wall 211 may exert a force on the support member 24 in the thickness direction Z of the first wall 211. For another example, if the insulating member 23 is provided with a first insulating wall 231 and a second insulating wall 232, the first insulating wall 231 and the second insulating wall 232 may exert a force on the support member 24 in the thickness direction Z of the first wall 211. The dimension of the support member 24 in the thickness direction Z of the first wall 211 may be slightly larger than the dimension of the accommodating cavity 26 in the thickness direction Z of the first wall 211, wherein the dimension of the accommodating cavity 26 in the thickness direction Z of the first wall 211 may refer to the distance between the two surfaces forming the accommodating cavity in the thickness direction Z of the first wall 211. During the assembly process, external force can be used to expand the size of the accommodating cavity 26 in the thickness direction Z of the first wall 211, and the supporting member 24 can be placed in the accommodating cavity 26. After the structure of the accommodating cavity 26 in the thickness direction Z of the first wall 211 is restored, the supporting member 24 can be clamped in the thickness direction Z of the first wall 211.

[0183] Optionally, the support member 24 may be interference-fitted with the accommodating cavity 26 in the width direction Y of the first wall 211. For example, if the support member 24 extends along the width direction Y of the first wall 211, the dimension of the support member 24 in the width direction Y of the first wall 211 may be slightly larger than the dimension of the accommodating cavity 26 in the width direction Y of the first wall 211. The dimension of the accommodating cavity 26 in the width direction Y of the first wall 211 may refer to the distance between the two surfaces of the insulating member 23 that contact the support member 24 in the width direction Y of the first wall 211. During assembly, an external force may be used to expand the dimension of the accommodating cavity 26 in the width direction Y of the first wall 211. After the support member 24 is placed into the accommodating cavity 26, the accommodating cavity 26 in the width direction Y of the first wall 211 is restored, thereby enabling the support member 24 to be clamped in the width direction Y of the first wall 211.

[0184] Optionally, the accommodating cavity 26 and the supporting member 24 may be interference-fitted in multiple directions simultaneously.

[0185] In this way, the support member 24 can be fixed in the accommodating cavity 26 more easily, so that the support member 24 is not easy to fall out of the accommodating cavity 26, which is beneficial for keeping the discharge channel unobstructed when high-temperature and high-pressure substances are generated inside the battery cell 20, and is beneficial for improving the reliability of the battery cell 20.

[0186] According to some embodiments of the present application, optionally, the surface of the support member 24 facing the electrode assembly 22 in the thickness direction Z of the first wall 211 and / or the surface of the support member 24 facing the first wall 211 in the thickness direction Z of the first wall 211 has an insulating layer.

[0187] Specifically, in some embodiments, an insulating layer may be provided on the surface of the support member 24 facing the first wall 211 to reduce the possibility that the support member 24 contacts the first wall 211 and causes the first wall 211 to be charged.

[0188] In some embodiments, the surface of the support member 24 facing the electrode assembly 22 is provided with an insulating layer to reduce the possibility that the support member 24 conducts the electrical energy generated by the electrode assembly 22 to the first wall 211 .

[0189] In some embodiments, the surfaces of the support member 24 facing the first wall 211 and the electrode assembly 22 may be provided with an insulating layer at the same time, or the surfaces of the support member 24 may be coated with an insulating material to improve the insulating effect of the support member 24 .

[0190] In some embodiments, the support member 24 may be made of an insulating material, for example, may be made of high-temperature resistant ceramic.

[0191] The insulating layer can improve the insulation performance between the support member 24 and the first wall 211 , reduce the possibility of the outer shell 21 of the battery cell 20 being charged by the support member 24 , and thus improve the reliability of the battery cell 20 .

[0192] The present application also provides a battery, comprising the battery cell 20 described in any of the above embodiments.

[0193] The present application also provides an electrical device, comprising the battery described in any of the above embodiments, wherein the battery is used to provide electrical energy to the electrical device.

[0194] The embodiment of the present application provides a battery cell 20. The housing 21 of the battery cell 20 includes a first wall 211 and a shell 212. The electrode assembly 22 is accommodated in the shell 212. The first wall 211 is provided with an electrode terminal 214 and a pressure relief mechanism 213. The electrode terminal 214 is electrically connected to the electrode assembly 22 via a connecting member 25. An insulating member 23 is provided between the first wall 211 and the electrode assembly 22. The insulating member 23 has a receiving cavity 26, and a support member 24 is accommodated in the receiving cavity 26. The insulating member 23 has an exhaust passage connecting the pressure relief mechanism 213 and the electrode assembly 22. The support member 24 is used to limit deformation of the exhaust passage. The melting point of the support member 24 can be higher than the melting point of the insulating member 23. In the event of thermal runaway inside the battery cell 20, the support member 24 is not easily melted under the action of high-temperature and high-pressure substances, and can maintain the shape and position of the insulating member 23. At the same time, it limits the movement of the electrode assembly 22 toward the first wall 211, keeps the discharge channel unobstructed, and enables the pressure relief mechanism 213 to be normally actuated to discharge high-temperature and high-pressure substances, thereby improving the reliability of the battery cell 20.

[0195] The above description is merely a specific embodiment of the present application, but the scope of protection of the present application is not limited thereto. Any changes or substitutions that can be easily conceived by a person skilled in the art within the technical scope disclosed in the present application should be included in the scope of protection of the present application. Therefore, the scope of protection of the present application should be based on the scope of protection of the claims.

Claims

1. A battery cell, characterized in that: include: A housing (21), the housing (21) having a first wall (211), the first wall (211) being provided with a pressure relief mechanism (213); an electrode assembly (22), the electrode assembly (22) being accommodated in the housing (21); an insulating member (23), the insulating member (23) being disposed between the electrode assembly (22) and the first wall (211), the insulating member (23) having a receiving cavity (26), and the insulating member (23) having a discharge channel connecting the pressure relief mechanism (213) and the electrode assembly (22); A support member (24) is accommodated in the accommodation chamber (26) and is used to limit deformation of the discharge passage.

2. The battery cell according to claim 1, characterized in that: The insulating component (23) comprises a first insulating wall (231), and the accommodating cavity (26) is formed between the first insulating wall (231) and the first wall (211).

3. The battery cell according to claim 2, characterized in that: A projection of the first insulating wall (231) in the thickness direction (Z) of the first wall (211) covers a projection of the supporting member (24) in the thickness direction (Z) of the first wall (211).

4. The battery cell according to claim 2 or 3, characterized in that: The insulating component (23) comprises a second insulating wall (232), which is arranged between the first insulating wall (231) and the first wall (211), and forms the accommodating cavity (26) between the second insulating wall (232) and the first insulating wall (231).

5. The battery cell according to claim 1, characterized in that: The insulating component (23) includes a second insulating wall (232), which is arranged on a surface of the insulating component (23) facing the first wall (211) in the thickness direction (Z) of the first wall (211), and the accommodating cavity (26) is formed between the second insulating wall (232) and the surface of the insulating component (23) facing the electrode assembly (22) in the thickness direction (Z) of the first wall (211).

6. The battery cell according to claim 4, characterized in that: The insulating component (23) comprises a connecting wall (233), wherein the connecting wall (233) connects the first insulating wall (231) and the second insulating wall (232), and the connecting wall (233) extends along the first direction (Z).

7. The battery cell according to claim 6, characterized in that: The connecting wall (233) is provided with a discharge hole (234) penetrating the connecting wall (233) in the thickness direction of the connecting wall (233).

8. The battery cell according to claim 7, characterized in that: The connecting wall (233) includes a first connecting portion (2331), and the first connecting portion (2331) is arranged on both sides of the pressure relief mechanism (213) in the length direction (X) of the first wall (211); the discharge hole (234) includes a first through hole (2341), and the first through hole (2341) passes through the first connecting portion (2331) in the length direction (X) of the first wall (211); the first through hole (2341) is used to form the discharge channel.

9. The battery cell according to any one of claims 1 to 8, characterized in that: The insulating member (23) has a second through hole (236) penetrating the insulating member (23) in the thickness direction (Z) of the first wall (211), the second through hole (236) being arranged opposite to the pressure relief mechanism (213), and the second through hole (236) being used to form the discharge channel.

10. The battery cell according to any one of claims 1 to 9, characterized in that: The supporting member (24) is disposed on an edge of the insulating member (23) on a plane perpendicular to a thickness direction (Z) of the first wall (211).

11. The battery cell according to claim 10, characterized in that: The supporting member (24) is located at an edge of the insulating member (23) in the width direction (Y) of the first wall (211).

12. The battery cell according to claim 11, characterized in that: The support members (24) are arranged at intervals along the length direction (X) of the first wall (211).

13. The battery cell according to any one of claims 10 to 12, characterized in that: The supporting member (24) is located at an edge of the insulating member (23) in the length direction (X) of the first wall (211).

14. The battery cell according to any one of claims 1 to 13, characterized in that: The supporting member (24) is arranged in the surrounding area of ​​the pressure relief mechanism (213).

15. The battery cell according to claim 14, characterized in that: The plurality of support members (24) enclose a surrounding area of ​​the pressure relief mechanism (213) to form a receiving space, and the pressure relief mechanism (213) is arranged in the receiving space.

16. The battery cell according to claims 10 to 15, characterized in that: The supporting member (24) is provided with a third through hole (241), and the third through hole (241) is used to form the discharge passage.

17. The battery cell according to any one of claims 1 to 16, characterized in that: The supporting member (24) comprises a long strip-shaped main body.

18. The battery cell according to any one of claims 1 to 17, characterized in that: The supporting member (24) has a melting point higher than that of the insulating member (23).

19. The battery cell according to claim 18, characterized in that: The melting point of the supporting member (24) is greater than 100°C.

20. The battery cell according to any one of claims 1 to 19, characterized in that: The first wall (211) is provided with an electrode terminal (214), and the battery cell comprises: A connecting member (25) is used to electrically connect the electrode terminal (214) and the electrode assembly (22); the insulating member (23) has a avoidance hole (235) that penetrates the insulating member (23) in the first direction (Z); at least a portion of the connecting member (25) is accommodated in the avoidance hole (235).

21. The battery cell according to any one of claims 1 to 20, characterized in that: The supporting member (24) and the accommodating cavity (26) are interference fit.

22. The battery cell according to any one of claims 1 to 21, characterized in that: The surface of the support member (24) facing the electrode assembly (22) in the thickness direction (Z) of the first wall (211) and / or the surface of the support member (24) facing the first wall (211) in the thickness direction (Z) of the first wall (211) has an insulating layer.

23. A battery, characterized in that: include: A battery cell as claimed in any one of claims 1 to 22.

24. An electrical device, characterized in that: The battery as claimed in claim 23 is used to provide electrical energy to the electrical device.

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