Battery cells, batteries and electrical equipment

Abstract

The present application provides a battery cell, a battery and an electrical device, and relates to the field of batteries. The battery cell includes an electrode assembly, a shell, a pressure relief mechanism and an insulating member. The shell is used to accommodate the electrode assembly. The shell has a wall portion arranged opposite to the electrode assembly along a first direction. The pressure relief mechanism is arranged on the wall portion. Along the first direction, the insulating member is at least partially located between the electrode assembly and the wall portion. A avoidance portion is provided at a position corresponding to the pressure relief mechanism of the insulating member, and the avoidance portion is used to avoid the pressure relief mechanism. The insulating member of the battery cell can not only insulate and isolate the electrode assembly from the shell, but also has a avoidance portion that can avoid the pressure relief mechanism at a position corresponding to the pressure relief mechanism, so that the insulating member will not interact with the pressure relief mechanism even under vibration conditions or squeezed by the electrode assembly, and will not affect the normal operation of the pressure relief mechanism, so that the pressure relief mechanism can open normally when the pressure inside the battery cell reaches the detonation pressure, thereby ensuring the normal operation of the battery cell.

Description

Technical Field

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

[0002] Batteries are widely used in new energy applications, such as electric vehicles and new energy vehicles, which have become a new trend in the automotive industry. Battery cells are equipped with pressure relief mechanisms to release internal pressure when it reaches the detonation pressure. However, these mechanisms often fail to open properly, preventing them from functioning properly. Summary of the Invention

[0003] The purpose of the embodiments of the present application is to provide a battery cell, a battery and an electrical device, which aims to improve the problem in the related art that the pressure relief mechanism often fails to open normally, resulting in failure to achieve the normal pressure relief function.

[0004] In a first aspect, an embodiment of the present application provides a battery cell, which includes an electrode assembly, a shell, a pressure relief mechanism and an insulating member, wherein the shell is used to accommodate the electrode assembly, the shell has a wall portion arranged opposite to the electrode assembly along a first direction, and the pressure relief mechanism is arranged on the wall portion; along the first direction, the insulating member is at least partially located between the electrode assembly and the wall portion; wherein a avoidance portion is provided at a position of the insulating member corresponding to the pressure relief mechanism, and the avoidance portion is used to avoid the pressure relief mechanism.

[0005] In the above technical solution, the insulating part of the battery cell can not only insulate and isolate the electrode assembly from the shell, but also has a avoidance portion that can avoid the pressure relief mechanism at a position corresponding to the pressure relief mechanism, so that even if the insulating part is in a vibration condition or is squeezed by the electrode assembly, it will not block the pressure relief mechanism or apply a large pressure, and will not affect the normal operation of the pressure relief mechanism. When the pressure inside the battery cell reaches the detonation pressure, the pressure relief mechanism can open normally, and will not open prematurely or late, thereby ensuring the normal operation of the battery cell.

[0006] As an optional technical solution of the embodiment of the present application, along the first direction, the projection of the outline of the avoidance portion on the wall is arranged around the pressure relief mechanism.

[0007] In the above technical solution, the outline of the avoidance portion defines an avoidance space, and the projection of the outline of the avoidance portion on the wall is arranged around the pressure relief mechanism, that is, the pressure relief mechanism falls within the avoidance space, so that the avoidance portion has a better avoidance effect on the pressure relief mechanism.

[0008] As an optional technical solution of the embodiment of the present application, along the first direction, the insulating member has a first surface facing the wall portion, and the avoidance portion is a groove recessed from the first surface in a direction away from the wall portion.

[0009] In the above technical solution, the relief portion is a groove formed in the insulating member. The interior space of the groove allows for the pressure relief mechanism to be avoided. This prevents the insulating member from contacting the pressure relief mechanism under vibration conditions or when squeezed by the electrode assembly, thereby preventing the mechanism from functioning properly and allowing the pressure relief mechanism to open normally and perform its normal pressure relief function. Furthermore, because the relief portion does not penetrate the insulating member, the insulating member can still insulate and isolate the electrode assembly from the wall, eliminating the need for additional insulating components.

[0010] As an optional technical solution of the embodiment of the present application, along the first direction, the insulating member has a first surface and a second surface arranged opposite to each other, and the avoidance portion is a through hole passing through the first surface and the second surface.

[0011] In the above technical solution, the escape portion is a through-hole extending along a first direction through the first and second surfaces of the insulating member, which are arranged opposite each other. The escape portion is configured as a through-hole to ensure sufficient escape space to allow the pressure relief mechanism to escape. Since the escape portion is a through-hole, it may affect the insulation performance of the insulating member. Therefore, an additional insulating component can be provided to isolate the electrode assembly from the wall. The solution in which the escape portion is a through-hole is suitable for situations where the thickness of the portion of the insulating member between the electrode assembly and the wall is relatively thin, thereby achieving a better escape effect.

[0012] As an optional technical solution of the embodiment of the present application, along the length direction of the avoidance portion, the size of the avoidance portion is a1, and the size of the pressure relief mechanism is a2, satisfying: 0.1≤a2 / a1≤1.

[0013] In the above technical solution, along the length direction of the avoidance portion, the size of the pressure relief mechanism is 0.1 to 1 times the size of the avoidance portion. In this way, while ensuring a good avoidance effect, it will not have too much impact on the insulating effect of the insulating part. In addition, when the insulating part supports the electrode assembly, it will not affect the supporting effect of the insulating part too much. If a2 / a1 is less than 0.1, the size of the avoidance portion is too large along the length direction of the avoidance portion, which may easily lead to a significant weakening of the insulating effect of the insulating part. When the insulating part supports the electrode assembly, the supporting effect is greatly deteriorated. If a2 / a1 is greater than 1, the size of the avoidance portion is smaller than the size of the pressure relief mechanism along the length direction of the avoidance portion, which may make it impossible for the avoidance portion to completely avoid the pressure relief mechanism.

[0014] As an optional technical solution of the embodiment of the present application, along the width direction of the avoidance portion, the size of the avoidance portion is b1, and the size of the pressure relief mechanism is b2, satisfying: 0.05≤b2 / b1.

[0015] In the above technical solution, along the width direction of the avoidance portion, the size of the pressure relief mechanism is greater than 0.05 times the size of the avoidance portion. In this way, while ensuring a good avoidance effect, it will not have a significant impact on the insulation effect of the insulating member. In addition, when the insulating member supports the electrode assembly, it will not affect the supporting effect of the insulating member too much. If b2 / b1 is less than 0.05, the size of the avoidance portion along the width direction of the avoidance portion is too large, which can easily lead to a significant weakening of the insulation effect of the insulating member. When the insulating member supports the electrode assembly, the supporting effect is greatly deteriorated.

[0016] As an optional technical solution of the embodiment of the present application, along the width direction of the avoidance portion, the size b1 of the avoidance portion and the size b2 of the pressure relief mechanism further satisfy: b2 / b1≤5.

[0017] In the above technical solution, since the insulating member may have a height difference along the width of the escape portion, the projection of the escape portion's profile on the wall along the first direction semi-encloses the pressure relief mechanism, achieving a better escape effect. For example, if one side of the insulating member is higher than the other along the width of the escape portion, the escape portion only needs to be located on the higher side to effectively escape the pressure relief mechanism. In this case, the dimensions of the pressure relief mechanism along the width of the escape portion can be larger than those of the escape portion. To achieve the desired semi-enclosed projection relationship, b2 / b1 is set to ≤ 5 to achieve a better escape effect.

[0018] As an optional technical solution of the embodiment of the present application, along the first direction, the depth of the avoidance portion is h, which satisfies 0.05mm≤h≤1mm.

[0019] In the above technical solution, by setting the depth of the relief portion to be greater than 0.05 mm and less than 1 mm, a good relief effect can be achieved while maintaining good insulation and support effects of the insulating member. If the depth of the relief portion along the first direction is less than 0.05 mm, the relief effect is poor. If the depth of the relief portion is greater than 1 mm, the insulation effect of the insulating member will be weakened.

[0020] As an optional technical solution of an embodiment of the present application, along the first direction, the projected area of ​​the electrode assembly on the wall is S1, and the area enclosed by the outline of the avoidance portion is S2, satisfying: 0.002<S2 / S1<0.8.

[0021] In the above technical solution, the area enclosed by the outline of the avoidance portion is 0.002 to 0.8 times the projected area of ​​the electrode assembly on the wall along the first direction. In this way, the size of the avoidance portion is relatively appropriate, which can achieve a good avoidance effect. At the same time, it will not have a significant impact on the insulation and support effects of the insulating member. If S2 / S1≤0.002, the avoidance portion is too small and cannot provide a avoidance effect for the pressure relief mechanism. If S2 / S1≥0.8, the avoidance portion is too large, causing the insulating member to lose its insulation and support effects.

[0022] As an optional technical solution of an embodiment of the present application, the insulating member includes an insulating plate, which is arranged between the electrode assembly and the wall portion along the first direction, and the insulating plate is provided with the avoidance portion.

[0023] In the above technical solution, the insulating plate serves as a support for the electrode assembly, securing it within the housing. Under vibration conditions or when squeezed by the electrode assembly, the insulating plate resists deformation, providing excellent insulation and support. A relief portion is provided on the insulating plate to prevent it from blocking the pressure relief mechanism, thereby ensuring its capacity.

[0024] As an optional technical solution of the embodiment of the present application, the insulating member includes a covering body, which covers the electrode assembly along the circumference of the electrode assembly, and the covering body is provided with the avoidance portion.

[0025] In the above technical solution, the covering body can cover the circumference of the electrode assembly, effectively separating the electrode assembly from the housing and providing good insulation. A relief portion is provided on the covering body to prevent the covering body from contacting the pressure relief mechanism under vibration conditions or when squeezed by the electrode assembly, thereby preventing the pressure relief mechanism from blocking and affecting its normal operation.

[0026] As an optional technical solution of an embodiment of the present application, the covering body has a first covering portion and a second covering portion located between the electrode assembly and the wall portion. Along the first direction, the first covering portion and the second covering portion are stacked, and the first covering portion is closer to the wall portion than the second covering portion; wherein the first covering portion is provided with the avoidance portion.

[0027] In the above technical solution, the first and second covering portions are stacked, with the first covering portion being the outermost covering portion. The first covering portion is prone to contact and blockage of the pressure relief mechanism. Therefore, the avoidance portion is positioned on the first covering portion to achieve a better avoidance effect. At the same time, the second covering portion still provides good insulation.

[0028] As an optional technical solution of an embodiment of the present application, the avoidance portion is a gap opened in the first covering portion.

[0029] In the above technical solution, the first covering part and the second covering part are stacked, the first covering part blocks a part of the second covering part, and the other part of the second covering part is exposed. In this way, the position of the first covering part is higher than the exposed part of the second covering part. The exposed part of the second covering part is not easy to contact with the pressure relief mechanism and affect the normal operation of the pressure relief mechanism. The avoidance part is set as a notch opened in the first covering part, and the notch faces the exposed part of the second covering part. The projection of the outline of the notch on the wall semi-surrounds the pressure relief mechanism to achieve a better avoidance effect, so that the pressure relief mechanism will not contact with the covering body and affect the normal operation of the pressure relief mechanism.

[0030] As an optional technical solution of the embodiment of the present application, the second covering portion is provided with the avoidance portion.

[0031] In the above technical solution, avoidance portions are provided on both the first covering portion and the second covering portion, and the avoidance effect is better.

[0032] In a second aspect, an embodiment of the present application further provides a battery, which includes a box and the above-mentioned battery cells, and the battery cells are accommodated in the box.

[0033] In a third aspect, an embodiment of the present application further provides an electrical device, which includes the above-mentioned battery. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the following is a brief introduction to the drawings required for use in the embodiments. It should be understood that the following drawings only show certain embodiments of the present application and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other relevant drawings can be obtained based on these drawings without creative work.

[0035] Figure 1 A schematic structural diagram of a vehicle provided in some embodiments of the present application;

[0036] Figure 2 An exploded view of a battery provided in accordance with some embodiments of the present application;

[0037] Figure 3 An exploded view of a battery cell provided in some embodiments of the present application;

[0038] Figure 4 A schematic front view of a battery cell provided in some embodiments of the present application;

[0039] Figure 5 for Figure 4 Cross-sectional view at the AA position;

[0040] Figure 6 for Figure 5 Enlarged view of position B in the middle;

[0041] Figure 7 A schematic structural diagram of an insulating member provided in some embodiments of the present application;

[0042] Figure 8 A schematic front view of an insulating member provided in some embodiments of the present application;

[0043] Figure 9 A schematic front view of a housing provided in some embodiments of the present application;

[0044] Figure 10 A schematic front view of a housing provided in some other embodiments of the present application;

[0045] Figure 11 A schematic structural diagram of an insulating member provided in some other embodiments of the present application;

[0046] Figure 12 A schematic front view of an insulating member provided in some other embodiments of the present application;

[0047] Figure 13 Schematic diagram of the structure of the insulating member provided in some other embodiments of the present application.

[0048] Icons: 10-housing; 11-first part; 12-second part; 20-battery cell; 21-electrode assembly; 22-housing; 221-end cover; 222-housing body; 2221-wall; 2222-pressure relief mechanism; 23-insulating member; 231-avoidance part; 232-insulating plate; 233-encapsulating body; 2331-first encapsulating part; 2332-second encapsulating part; 100-battery; 200-controller; 300-motor; 1000-vehicle. DETAILED DESCRIPTION

[0049] To make the purpose, technical solutions, and advantages of the embodiments of this application more clear, the technical solutions in the embodiments of this application will be clearly described below in conjunction with the drawings in the embodiments of this application. Obviously, the described embodiments are part of the embodiments of this application, not all of the embodiments. Based on the embodiments in this application, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of this application.

[0050] Unless otherwise defined, all technical and scientific terms used in this application have the same meanings as commonly understood by those skilled in the art to which this application belongs. The terms used in the specification of this application are for the purpose of describing specific embodiments only and are not intended to limit this application. The terms "including" and "having" and any variations thereof in the specification and claims of this application and the above-mentioned drawings are intended to cover non-exclusive inclusions. The terms "first" and "second" in the specification and claims of this application or the above-mentioned drawings are used to distinguish different objects, rather than to describe a specific order or a primary-secondary relationship.

[0051] 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.

[0052] In the description of this application, it should be noted that, unless otherwise expressly specified or limited, the terms "mounted," "connected," "connected," and "attached" should be understood in a broad sense. For example, they may refer to fixed connections, detachable connections, or integral connections; they may refer to direct connections, indirect connections through an intermediate medium, or internal connections between two components. Those skilled in the art will understand the specific meanings of the above terms in this application based on specific circumstances.

[0053] The term "and / or" in this application simply describes an association between related objects, indicating that three possible relationships exist. For example, A and / or B can represent: A exists alone, A and B exist simultaneously, and B exists alone. In addition, the character " / " in this application generally indicates that the related objects are in an "or" relationship.

[0054] 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.

[0055] The term "plurality" used in this application refers to two or more (including two).

[0056] In this application, battery cells may include lithium-ion secondary battery cells, lithium-ion primary battery cells, lithium-sulfur battery cells, sodium-lithium-ion battery cells, sodium-ion battery cells, or magnesium-ion battery cells, 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.

[0057] 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.

[0058] 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 comprises 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 portion of the positive electrode collector not coated with the positive active material layer protrudes from the portion coated with the positive active material layer. The portion of the positive electrode collector not coated with the positive active material layer 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 active material can be lithium cobalt oxide, lithium iron phosphate, ternary lithium, or lithium manganese oxide. The negative electrode sheet comprises 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 portion of the negative electrode collector not coated with the negative active material layer protrudes from the portion coated with the negative active material layer. The portion of the negative electrode collector not coated with the negative active material layer serves as the negative electrode tab. The negative electrode current collector can be made of copper, and the negative active material can be carbon or silicon, among others. To ensure high current flow without melting, multiple positive tabs are stacked together, and multiple negative tabs are stacked together. The separator can be made of materials such as PP (polypropylene) or PE (polyethylene). Furthermore, the electrode assembly can be a wound or laminated structure, but the present invention is not limited thereto.

[0059] The development of battery technology must take into account multiple design factors at the same time, such as energy density, cycle life, discharge capacity, charge and discharge rate and other performance parameters. In addition, battery safety must also be considered.

[0060] To ensure the safety of battery cells, a pressure relief mechanism can be installed on the battery cells. When the internal pressure of the battery cell reaches the detonation pressure, the pressure relief mechanism opens to release the pressure inside the battery cell, thereby reducing the risk of battery cell explosion or fire.

[0061] The inventors have noticed that the pressure relief mechanism often fails to open normally, resulting in failure to achieve the normal pressure relief function.

[0062] The inventors further discovered that under vibration conditions, the electrode assembly squeezes the insulating member, making it more likely to come into contact with the pressure relief mechanism, blocking or damaging it. This can prevent the pressure relief mechanism from opening properly or even render it completely inoperative. Furthermore, after a period of battery cell use, the electrode assembly expands, squeezing the insulating member and making it more likely to come into contact with the pressure relief mechanism, blocking or damaging it and similarly affecting its proper function.

[0063] In view of this, an embodiment of the present application provides a battery cell, which avoids the pressure relief mechanism by setting a avoidance portion at a position corresponding to the pressure relief mechanism on the insulating part, so that even if the insulating part is in a vibrating condition or is squeezed by the electrode assembly, it will not block or apply a large pressure to the pressure relief mechanism, and will not affect the normal operation of the pressure relief mechanism. When the pressure inside the battery cell reaches the detonation pressure, the pressure relief mechanism can open normally and will not open prematurely or late, thereby ensuring the normal operation of the battery cell.

[0064] The technical solutions described in the embodiments of the present application are applicable to batteries and electrical devices using batteries.

[0065] Electrically powered devices may include vehicles, mobile phones, portable devices, laptop computers, ships, spacecraft, electric toys, and electric tools. Spacecraft include airplanes, rockets, space shuttles, and spacecraft. Electric toys include fixed or mobile electric toys, such as game consoles, electric car toys, electric ship toys, and electric airplane toys. Electric tools include metal cutting power tools, grinding power tools, assembly power tools, and railway power tools, such as electric drills, electric grinders, electric wrenches, electric screwdrivers, electric hammers, impact drills, concrete vibrators, and electric planers. The embodiments of the present application do not impose any special restrictions on the above-mentioned electrical devices.

[0066] For the convenience of description, the following embodiments are described by taking the electric device as a vehicle 1000 as an example.

[0067] Please refer to Figure 1 , Figure 1A schematic structural diagram of a vehicle 1000 provided for some embodiments of the present application. The vehicle 1000 may be a fuel vehicle, a gas vehicle or a new energy vehicle. The new energy vehicle may be a pure electric vehicle, a hybrid vehicle or an extended-range vehicle, etc. A battery 100 is provided inside the vehicle 1000. The battery 100 may be provided at the bottom, head or tail of the vehicle 1000. The battery 100 may be used to power the vehicle 1000. For example, the battery 100 may serve as an operating power source for the vehicle 1000. The vehicle 1000 may further include a controller 200 and a motor 300. The controller 200 is used to control the battery 100 to power the motor 300, for example, to meet the power requirements for starting, navigating and driving the vehicle 1000.

[0068] In some embodiments of the present application, the battery 100 can serve not only as an operating power source for the vehicle 1000, but also as a driving power source for the vehicle 1000, replacing or partially replacing fuel or natural gas to provide driving power for the vehicle 1000.

[0069] Please refer to Figure 2 , Figure 2 An exploded view of a battery 100 provided in some embodiments of the present application. The battery 100 includes a housing 10 and battery cells 20, with the battery cells 20 housed within the housing 10. The housing 10 is used to provide a storage space for the battery cells 20 and can have various structures. In some embodiments, the housing 10 can include a first portion 11 and a second portion 12, which overlap each other and together define a storage space for the battery cells 20. The second portion 12 can be a hollow structure with one end open. The first portion 11 can be a plate-like structure, with the first portion 11 overlapping the open side of the second portion 12, so that the first portion 11 and the second portion 12 together define a storage space. The first portion 11 and the second portion 12 can also be hollow structures with one end open, with the open side of the first portion 11 overlapping the open side of the second portion 12. Of course, the housing 10 formed by the first portion 11 and the second portion 12 can have various shapes, such as a cylinder, a rectangular parallelepiped, etc.

[0070] In the battery 100, there may be multiple battery cells 20, and the multiple battery cells 20 may be connected in series, in parallel, or in a hybrid connection. A hybrid connection refers to a combination of series and parallel connections among the multiple battery cells 20. The multiple battery cells 20 may be directly connected in series, in parallel, or in a hybrid connection, and then the entire battery cell 20 may be housed within the housing 10. Alternatively, the battery 100 may be constructed by first connecting multiple battery cells 20 in series, in parallel, or in a hybrid connection to form a battery module, which is then connected in series, in parallel, or in a hybrid connection to form a complete battery module, and then housed within the housing 10. The battery 100 may also include other structures, such as a busbar assembly for electrically connecting the multiple battery cells 20.

[0071] Each battery cell 20 may be a secondary battery cell or a primary battery cell; it may also be a lithium-sulfur battery cell, a sodium-ion battery cell, or a magnesium-ion battery cell, but is not limited thereto. The battery cell 20 may be cylindrical, flat, rectangular, or in other shapes.

[0072] Please refer to Figure 3 , Figure 3 The exploded view of the battery cell 20 provided in some embodiments of the present application. The battery cell 20 refers to the smallest unit that constitutes the battery 100. Figure 3 The battery cell 20 includes an electrode assembly 21 , a housing 22 , and other functional components. The housing 22 includes an end cap 221 and a housing body 222 , wherein the end cap 221 is connected to the housing body 222 .

[0073] The end cap 221 refers to a component that covers the opening of the shell body 222 to isolate the internal environment of the battery cell 20 from the external environment. Without limitation, the shape of the end cap 221 can be adapted to the shape of the shell body 222 to match the shell body 222. Optionally, the end cap 221 can be made of a material with a certain hardness and strength (such as aluminum alloy), so that the end cap 221 is not easily deformed when squeezed or collided, so that the battery cell 20 can have a higher structural strength and the safety performance can also be improved. Functional components such as electrode terminals can be provided on the end cap 221. The electrode terminal can be used to electrically connect to the electrode assembly 21 for outputting or inputting electrical energy of the battery cell 20. The material of the end cap 221 can also be various, such as copper, iron, aluminum, stainless steel, aluminum alloy, plastic, etc., and the embodiments of the present application do not impose any special restrictions on this.

[0074] The shell body 222 is a component that cooperates with the end cap 221 to form the internal environment of the battery cell 20. This internal environment can be used to accommodate the electrode assembly 21, electrolyte, and other components. The shell body 222 and the end cap 221 can be independent components. An opening can be provided in the shell body 222, and the end cap 221 is placed over the opening to form the internal environment of the battery cell 20. Alternatively, the end cap 221 and the shell body 222 can be integrated. Specifically, the end cap 221 and the shell body 222 can form a common connection surface before other components are inserted into the shell. When the interior of the shell body 222 needs to be encapsulated, the end cap 221 is placed over the shell body 222. The shell body 222 can have a variety of shapes and sizes, such as a rectangular parallelepiped, a cylindrical shape, a hexagonal prism, etc. Specifically, the shape of the shell body 222 can be determined based on the specific shape and size of the electrode assembly 21. The shell body 222 can be made of a variety of materials, such as copper, iron, aluminum, stainless steel, aluminum alloy, plastic, etc., and the embodiment of the present application does not impose any special restrictions on this.

[0075] The electrode assembly 21 is a component in the battery cell 20 where electrochemical reactions occur. One or more electrode assemblies 21 may be contained in the housing 22. The electrode assembly 21 is mainly formed by winding or stacking positive and negative electrode sheets, and a separator is usually provided between the positive and negative electrode sheets. The parts of the positive and negative electrode sheets with active materials constitute the main body of the electrode assembly 21, and the parts of the positive and negative electrode sheets without active materials each constitute a tab. The positive tab and the negative tab may be located together at one end of the main body or respectively at both ends of the main body. During the charge and discharge process of the battery 100, the positive electrode active material and the negative electrode active material react with the electrolyte, and the tabs connect the electrode terminals to form a current loop.

[0076] Please refer to Figure 3 、 Figure 4 、 Figure 5 and Figure 6 , Figure 4 This is a schematic front view of a battery cell 20 provided in some embodiments of the present application. Figure 5 for Figure 4 Cross-sectional view at position AA. Figure 6 for Figure 5An enlarged view of position B in the figure. An embodiment of the present application provides a battery cell 20, which includes an electrode assembly 21, a shell 22, a pressure relief mechanism 2222 and an insulating member 23. The shell 22 is used to accommodate the electrode assembly 21. The shell 22 has a wall portion 2221 arranged opposite to the electrode assembly 21 along a first direction, and the pressure relief mechanism 2222 is arranged on the wall portion 2221. Along the first direction, the insulating member 23 is at least partially located between the electrode assembly 21 and the wall portion 2221. Among them, the insulating member 23 is provided with an avoidance portion 231 at a position corresponding to the pressure relief mechanism 2222, and the avoidance portion 231 is used to avoid the pressure relief mechanism 2222.

[0077] The first direction is the direction in which the wall portion 2221 of the housing 22 provided with the pressure relief mechanism 2222 points toward the electrode assembly 21 along an axis perpendicular to the wall portion 2221 of the housing 22 .

[0078] The housing 22 has multiple walls, such as a bottom wall, side walls, and a top wall. The wall portion 2221 refers to the wall on which the pressure relief mechanism 2222 is provided. For example, if the pressure relief mechanism 2222 is provided on the bottom wall, the wall portion 2221 refers to the bottom wall of the housing 22. For another example, if the pressure relief mechanism 2222 is provided on the top wall, the wall portion 2221 refers to the top wall of the housing 22. For another example, if the pressure relief mechanism 2222 is provided on the side wall, the wall portion 2221 refers to the side wall of the housing 22. For another example, if the pressure relief mechanism 2222 is provided on the end cover 221, the wall portion 2221 may also refer to the end cover 221.

[0079] In this embodiment, the first direction is as follows Figure 3 The C direction shown in .

[0080] The insulating member 23 is a component made of an insulating material with insulating properties. Insulating materials include, but are not limited to, plastic or rubber. The insulating member 23 is used to insulate the electrode assembly 21 from the wall portion 2221, preventing electrical connection between the electrode assembly 21 and the wall portion 2221, which could cause a short circuit in the battery cells 20. The insulating member 23 may be located entirely or partially between the electrode assembly 21 and the wall portion 2221.

[0081] The escape portion 231 is a portion of the insulating member 23 that provides a relief function. The escape portion 231 can enclose a relief space, allowing the pressure relief mechanism 2222 to be accommodated within the relief space, thereby avoiding the insulating member 23. The shape of the escape portion 231 is not limited. For example, the escape portion 231 can be rectangular, elliptical, circular, triangular, hexagonal, etc.

[0082] The insulating part 23 of the battery cell 20 can not only insulate and isolate the electrode assembly 21 and the shell 22, but also has an avoidance portion 231 that can avoid the pressure relief mechanism 2222 at a position corresponding to the pressure relief mechanism 2222. Therefore, even if the insulating part 23 is in a vibration condition or is squeezed by the electrode assembly 21, it will not block the pressure relief mechanism 2222 or apply a large pressure, and will not affect the normal operation of the pressure relief mechanism 2222. When the pressure inside the battery cell 20 reaches the detonation pressure, the pressure relief mechanism 2222 can open normally without opening prematurely or delaying the opening, thereby ensuring the normal operation of the battery cell 20.

[0083] In some embodiments, along the first direction, a projection of the outline of the avoidance portion 231 on the wall portion 2221 is disposed around the pressure relief mechanism 2222 .

[0084] The “contour of the avoidance portion 231” refers to the structure of the wall surfaces that enclose the avoidance space in the avoidance portion 231. Taking the avoidance portion 231 as a hole as an example, the contour of the avoidance portion 231 is the sidewall of the hole.

[0085] The phrase "the projection of the outline of the relief portion 231 on the wall portion 2221 is disposed around the pressure relief mechanism 2222" includes both the projection of the outline of the relief portion 231 on the wall portion 2221 partially surrounding the pressure relief mechanism 2222 and the projection of the outline of the relief portion 231 on the wall portion 2221 completely surrounding the pressure relief mechanism 2222. Furthermore, if the projection of the outline of the relief portion 231 on the wall portion 2221 coincides with the outer periphery of the pressure relief mechanism 2222, it should also be understood that the projection of the outline of the relief portion 231 on the wall portion 2221 is disposed around the pressure relief mechanism 2222.

[0086] The outline of the avoidance portion 231 defines an avoidance space, and the projection of the outline of the avoidance portion 231 on the wall portion 2221 is arranged around the pressure relief mechanism 2222, that is, the pressure relief mechanism 2222 falls within the avoidance space, so that the avoidance portion 231 has a better avoidance effect on the pressure relief mechanism 2222.

[0087] In some embodiments, along the first direction, the insulating member 23 has a first surface facing the wall portion 2221 . The escape portion 231 is a groove recessed from the first surface along a direction away from the wall portion 2221 .

[0088] The first surface is the surface of the insulating member 23 that is opposite the wall portion 2221. The phrase "the relief portion 231 is a groove that is recessed from the first surface in a direction away from the wall portion 2221" can be understood to mean that the relief portion 231 is a groove formed in the first surface. The groove can also be understood as a blind hole.

[0089] The relief portion 231 is a groove formed in the insulating member 23. The interior space of the groove allows for the pressure relief mechanism 2222 to be avoided. This prevents the insulating member 23 from contacting the pressure relief mechanism 2222 under vibration conditions or when squeezed by the electrode assembly 21, thereby preventing the normal operation of the pressure relief mechanism 2222. This allows the pressure relief mechanism 2222 to open normally and achieve its normal pressure relief function. Furthermore, because the relief portion 231 does not penetrate the insulating member 23, the insulating member 23 can still insulate and isolate the electrode assembly 21 from the wall portion 2221, eliminating the need for additional insulating components.

[0090] In some embodiments, along the first direction, the insulating member 23 has a first surface and a second surface that are oppositely arranged, and the avoiding portion 231 is a through hole that penetrates the first surface and the second surface.

[0091] The first surface and the second surface are two surfaces disposed opposite to each other on the insulating member 23. The first surface may be a surface opposite to the wall portion 2221, and the second surface may be a surface opposite to the wall portion 2221.

[0092] “The avoidance portion 231 is a through hole penetrating the first surface and the second surface” can also be understood as that along the first direction, the avoidance portion 231 is a through hole recessed from the first surface in a direction away from the wall portion 2221 and extending to the second surface.

[0093] The avoidance portion 231 is a through hole that passes through the first and second surfaces of the insulating member 23 that are arranged opposite to each other along the first direction. The avoidance portion 231 is set as a through hole to ensure that sufficient avoidance space is formed to avoid the pressure relief mechanism 2222. Since the avoidance portion 231 is a through hole, it may affect the insulation performance of the insulating member 23. Therefore, an additional insulating component can be provided to isolate the electrode assembly 21 and the wall portion 2221. Optionally, the solution in which the avoidance portion 231 is a through hole can be applied to the case where the thickness of the portion of the insulating member 23 between the electrode assembly 21 and the wall portion 2221 is relatively thin, so as to achieve a better avoidance effect.

[0094] Please refer to Figure 7 、 Figure 8 、 Figure 9 and Figure 10 , Figure 7 This is a schematic structural diagram of the insulating member 23 provided in some embodiments of the present application. Figure 8 This is a schematic front view of the insulating member 23 provided in some embodiments of the present application. Figure 9 This is a schematic front view of the housing 22 provided in some embodiments of the present application. Figure 10 Schematic front views of the housing 22 according to some other embodiments of the present application. In some embodiments, along the length direction of the avoidance portion 231, the dimension of the avoidance portion 231 is a1, and the dimension of the pressure relief mechanism 2222 is a2, satisfying the following: 0.1≤a2 / a1≤1.

[0095] Taking the avoidance portion 231 as a rectangle as an example, the length direction of the avoidance portion 231 is parallel to or coincides with the long side of the rectangle. Taking the avoidance portion 231 as an ellipse as an example, the length direction of the avoidance portion 231 coincides with the long axis of the ellipse.

[0096] In the embodiments of the present application, the shape of the pressure relief mechanism 2222 is not limited. The pressure relief mechanism 2222 can be in the shape of a "king" character, or in the shape of a runway, etc. Along the length direction of the avoidance portion 231, the size of the pressure relief mechanism 2222 refers to the distance between one end and the other end of the pressure relief mechanism 2222 in the length direction of the avoidance portion 231.

[0097] Along the length direction of the avoidance portion 231, the ratio of the size of the pressure relief mechanism 2222 to the size of the avoidance portion 231 can be: a2 / a1 = 0.1, 0.3, 0.5, 0.7, 0.9, etc.

[0098] Along the length direction of the avoidance portion 231, the size of the pressure relief mechanism 2222 is 0.1 to 1 times the size of the avoidance portion 231. In this way, while ensuring a good avoidance effect, it will not have too much impact on the insulation effect of the insulating part 23. In addition, when the insulating part 23 supports the electrode assembly 21 and the wall portion 2221, it will not too much affect the support effect of the insulating part 23 and the avoidance effect of the avoidance portion 231. That is to say, when subjected to external impacts, vibrations or internal and external squeezes, the part of the insulating part 23 located between the electrode assembly 21 and the wall portion 2221, except for the avoidance portion 231, first contacts the wall portion 2221, thereby preventing the avoidance portion 231 from contacting the pressure relief mechanism 2222, enabling the avoidance portion 231 to achieve avoidance. Once the area occupied by the avoidance portion 231 on the insulating part located between the electrode assembly 21 and the wall portion 2221 is too large, the insulating part 23 will not have enough area to support the electrode assembly 21 or the wall portion 2221, and the avoidance portion 231 cannot maintain a certain gap with the pressure relief mechanism 2222 well to play the avoidance role. If a2 / a1 < 0.1, then along the length direction of the avoidance portion 231, the size of the avoidance portion 231 is too large, which is likely to cause a significant reduction in the insulation effect of the insulating part 23. When the insulating part 23 supports the electrode assembly 21, the support effect becomes significantly worse. And if a2 / a1 > 1, then along the length direction of the avoidance portion 231, the size of the avoidance portion 231 is smaller than the size of the pressure relief mechanism 2222, which may cause the avoidance portion 231 to be unable to completely avoid the pressure relief mechanism 2222.

[0099] In some embodiments, along the width direction of the avoidance portion 231, the size of the avoidance portion 231 is b1, and the size of the pressure relief mechanism 2222 is b2, satisfying: 0.05 ≤ b2 / b1.

[0100] For example, if the avoidance portion 231 is a rectangle, the width direction of the avoidance portion 231 is parallel to or coincides with the short side of the rectangle. For example, if the avoidance portion 231 is an ellipse, the width direction of the avoidance portion 231 coincides with the short axis of the ellipse.

[0101] Along the width direction of the escape portion 231 , the size of the pressure relief mechanism 2222 refers to the distance from one end to the other end of the pressure relief mechanism 2222 in the width direction of the escape portion 231 .

[0102] Along the width direction of the avoidance portion 231 , the ratio of the size of the pressure relief mechanism 2222 to the size of the avoidance portion 231 may be: b2 / b1=0.01, 0.1, 0.3, 0.5, 0.7, 0.9, etc.

[0103] Along the width direction of the avoidance portion 231, the size of the pressure relief mechanism 2222 is greater than 0.05 times the size of the avoidance portion 231. In this way, while ensuring a good avoidance effect, it will not have much impact on the insulation effect of the insulating member 23. In addition, when the insulating member 23 supports the electrode assembly 21, it will not affect the supporting effect of the insulating member 23 too much. If b2 / b1 is less than 0.05, the size of the avoidance portion 231 is too large along the width direction of the avoidance portion 231, which may easily lead to a significant weakening of the insulation effect of the insulating member 23. When the insulating member 23 supports the electrode assembly 21, the supporting effect is greatly deteriorated.

[0104] In some embodiments, along the width direction of the avoidance portion 231 , the size b1 of the avoidance portion 231 and the size b2 of the pressure relief mechanism 2222 further satisfy: b2 / b1≤5.

[0105] Along the width direction of the avoidance portion 231 , the ratio of the size of the pressure relief mechanism 2222 to the size of the avoidance portion 231 may be: b2 / b1 = 1, 2, 3, 4, 5, etc.

[0106] Because the insulating member 23 may have a height difference in the width direction of the avoidance portion 231, a better avoidance effect can be achieved by setting the profile of the avoidance portion 231 in the projection of the wall portion 2221 to semi-enclose the pressure relief mechanism 2222. For example, if one side of the insulating member 23 is higher than the other side along the width direction of the avoidance portion 231, the avoidance portion 231 only needs to be set on the higher side to achieve the effect of avoiding the pressure relief mechanism 2222. In this case, the size of the pressure relief mechanism 2222 can be larger than the size of the avoidance portion 231 along the width direction of the avoidance portion 231. In order to meet the relationship of projected semi-enclosure, b2 / b1 is set to ≤ 5 to achieve a better avoidance effect.

[0107] In some embodiments, along the first direction, the depth of the avoidance portion 231 is h, which satisfies 0.05 mm ≤ h ≤ 1 mm.

[0108] The depth of the escape portion 231 refers to a distance along the first direction that the escape portion 231 is recessed from the first surface toward a direction away from the wall portion 2221 .

[0109] The depth of the avoidance portion 231 can be: h=0.05 mm, 0.1 mm, 0.2 mm, 0.5 mm, 0.8 mm, 0.9 mm, etc.

[0110] By ensuring that the depth of the relief portion 231 is greater than 0.05 mm and less than 1 mm, a good relief effect can be achieved while maintaining good insulation and support effects of the insulating member 23. If the depth of the relief portion 231 along the first direction is less than 0.05 mm, the relief effect is poor. If the depth of the relief portion 231 is greater than 1 mm, the insulation effect of the insulating member 23 is weakened.

[0111] In some embodiments, along the first direction, the projection area of ​​the electrode assembly 21 on the wall portion 2221 is S1, and the area enclosed by the outline of the avoidance portion 231 is S2, satisfying: 0.002<S2 / S1<0.8.

[0112] When the electrode assembly 21 is wound or stacked into a rectangular parallelepiped shape, along the first direction, the projected area of ​​the electrode assembly 21 on the wall portion 2221 may be equal to the area of ​​the surface of the electrode assembly 21 facing the wall portion 2221. When the electrode assembly 21 is wound into a cylindrical shape and the first direction coincides with the axis of the cylinder, the projected area of ​​the electrode assembly 21 on the wall portion 2221 is equal to the area of ​​the top or bottom surface of the electrode assembly 21.

[0113] The area enclosed by the outline of the avoidance portion 231 represents the size of the avoidance portion 231. The larger the area enclosed by the outline of the avoidance portion 231, the larger the avoidance portion 231. The smaller the area enclosed by the outline of the avoidance portion 231, the smaller the avoidance portion 231.

[0114] The ratio of the area enclosed by the outline of the avoidance portion 231 to the projected area of ​​the electrode assembly 21 on the wall portion 2221 along the first direction can be: S2 / S1=0.005, 0.01, 0.05, 0.1, 0.2, 0.4, 0.6, 0.7, 0.75, etc.

[0115] The area enclosed by the outline of the avoidance portion 231 is 0.002 to 0.8 times (excluding 0.002 and 0.8) the projected area of ​​the electrode assembly 21 on the wall portion 2221 along the first direction. In this way, the size of the avoidance portion 231 is relatively appropriate, which can achieve a better avoidance effect. At the same time, it will not have much impact on the insulation effect and support effect of the insulating member 23. If S2 / S1≤0.002, the avoidance portion 231 is small and cannot achieve an avoidance effect on the pressure relief mechanism 2222. If S2 / S1≥0.8, the avoidance portion 231 is large, causing the insulating member 23 to lose its insulation and support effects. Once the area occupied by the avoidance portion 231 on the insulating member between the electrode assembly 21 and the wall portion 2221 is too large, the insulating member 23 cannot have enough area to support the electrode assembly 21, the wall portion 2221 or ensure insulation, and the avoidance portion 231 cannot maintain a certain gap with the pressure relief mechanism 2222 to achieve an avoidance effect.

[0116] In some embodiments, the insulating member 23 includes an insulating plate 232 . The insulating plate 232 is disposed between the electrode assembly 21 and the wall portion 2221 along the first direction. The insulating plate 232 is provided with a relief portion 231 .

[0117] The insulating plate 232 is a plate-like structure. It is disposed between the electrode assembly 21 and the wall portion 2221 to insulate the two. For example, the insulating plate 232 may be an insulating base plate, the wall portion 2221 may be the bottom wall of the housing 22, and the pressure relief mechanism 2222 may be disposed on the bottom wall of the housing 22. In this manner, the insulating plate 232 provides support for the electrode assembly 21.

[0118] The insulating plate 232 serves as a support for the electrode assembly 21, securing it within the housing 22. Under vibration conditions or when squeezed by the electrode assembly 21, the insulating plate 232 resists deformation, providing excellent insulation and support. A relief portion 231 is provided on the insulating plate 232 to prevent it from blocking the pressure relief mechanism 2222, thereby ensuring the pressure relief capability of the pressure relief mechanism 2222.

[0119] Please refer to Figure 11 and Figure 12 , Figure 11 Schematic diagram of the structure of the insulating member 23 provided in some other embodiments of the present application. Figure 12 Schematic front views of the insulating member 23 provided in some other embodiments of the present application. In some other embodiments, the insulating member 23 includes a covering body 233 , which covers the electrode assembly 21 along the circumference of the electrode assembly 21 , and the covering body 233 is provided with an escape portion 231 .

[0120] The covering 233 is an insulating portion that covers the electrode assembly 21. For example, the covering 233 can be a Mylar film. A relief portion 231 is provided on the Mylar film to provide relief for the pressure relief mechanism 2222.

[0121] The covering 233 circumferentially covers the electrode assembly 21, effectively separating the electrode assembly 21 from the housing 22 and providing good insulation. A relief portion 231 is provided on the covering 233 to prevent contact between the covering 233 and the pressure relief mechanism 2222 under vibration conditions or when squeezed by the electrode assembly 21, thereby preventing the pressure relief mechanism 2222 from blocking and affecting its normal operation.

[0122] In some embodiments, the covering body 233 includes a first covering portion 2331 and a second covering portion 2332 located between the electrode assembly 21 and the wall portion 2221. Along a first direction, the first covering portion 2331 and the second covering portion 2332 are stacked, with the first covering portion 2331 being closer to the wall portion 2221 than the second covering portion 2332. The first covering portion 2331 is provided with a relief portion 231.

[0123] The second covering portion 2332 is the portion of the covering body 233 that is first wound when wrapping the electrode assembly 21. The second covering portion 2332 is close to the electrode assembly 21. The first covering portion 2331 is the portion of the covering body 233 that is wound last (or the end portion) when wrapping the electrode assembly 21. The first covering portion 2331 is away from the electrode assembly 21 and close to the wall portion 2221. After wrapping, the first covering portion 2331 and the second covering portion 2332 are stacked in the first direction.

[0124] The first covering portion 2331 and the second covering portion 2332 are both located between the electrode assembly 21 and the wall portion 2221, and both have portions corresponding to the pressure relief mechanism 2222. Since the first covering portion 2331 is closer to the pressure relief mechanism 2222, the avoidance portion 231 is provided on the first covering portion 2331 to avoid the pressure relief mechanism 2222.

[0125] The first covering portion 2331 and the second covering portion 2332 are stacked, with the first covering portion 2331 being the outer covering portion. The first covering portion 2331 is prone to contact and block the pressure relief mechanism 2222. Therefore, the avoidance portion 231 is positioned within the first covering portion 2331 to achieve a better avoidance effect. At the same time, the second covering portion 2332 still provides good insulation.

[0126] In some embodiments, the avoiding portion 231 is a notch defined in the first covering portion 2331 .

[0127] The first covering portion 2331 can completely cover the second covering portion 2332, or it can partially cover the second covering portion 2332, leaving a portion of the second covering portion 2332 exposed. This creates a height difference between the surface of the first covering portion 2331 near the wall portion 2221 and the surface of the second covering portion 2332 near the wall portion 2221. This allows the pressure relief mechanism 2222 to be easily accessible by simply creating a notch in the first covering portion 2331.

[0128] The first covering portion 2331 and the second covering portion 2332 are stacked, with the first covering portion 2331 covering a portion of the second covering portion 2332, and the other portion of the second covering portion 2332 being exposed. In this way, the position of the first covering portion 2331 is higher than the exposed portion of the second covering portion 2332. The exposed portion of the second covering portion 2332 is not likely to come into contact with the pressure relief mechanism 2222 and affect the normal operation of the pressure relief mechanism 2222. The avoidance portion 231 is configured as a notch opened in the first covering portion 2331, with the notch facing the exposed portion of the second covering portion 2332. The projection of the outline of the notch on the wall portion 2221 semi-encloses the pressure relief mechanism 2222, so as to achieve a better avoidance effect, so that the pressure relief mechanism 2222 will not come into contact with the covering body 233 and affect the normal operation of the pressure relief mechanism 2222.

[0129] Please refer to Figure 13 , Figure 13 Schematic diagram of the structure of the insulating member 23 provided in some other embodiments of the present application. In some other embodiments, the second covering portion 2332 is provided with an escape portion 231. The escape portion 231 is provided on both the first covering portion 2331 and the second covering portion 2332, which has a better escape effect.

[0130] In some embodiments, the insulating member 23 includes an insulating plate 232 and a covering 233, wherein the covering 233 covers the electrode assembly 21, and the insulating plate 232 is located between the covering 233 and the wall 2221. The insulating plate 232 is provided with a relief portion 231, and the covering 233 may or may not be provided with the relief portion 231.

[0131] The embodiment of the present application further provides a battery 100 , which includes a housing 10 and the aforementioned battery cells 20 , wherein the battery cells 20 are accommodated in the housing 10 .

[0132] An embodiment of the present application further provides an electric device, which includes the battery 100 described above.

[0133] According to some embodiments of this application, please refer to Figures 3 to 12 .

[0134] The present embodiment provides a battery cell 20, which includes an electrode assembly 21, a housing 22, a pressure relief mechanism 2222, and an insulating member 23. The housing 22 is configured to accommodate the electrode assembly 21. The housing 22 has a wall portion 2221 disposed opposite the electrode assembly 21 along a first direction, and the pressure relief mechanism 2222 is disposed on the wall portion 2221.

[0135] Along the first direction, the insulating member 23 is at least partially located between the electrode assembly 21 and the wall portion 2221. A relief portion 231 is provided on the insulating member 23 at a position corresponding to the pressure relief mechanism 2222. The relief portion 231 is configured to avoid the pressure relief mechanism 2222. Along the first direction, the insulating member 23 has a first surface facing the wall portion 2221. The relief portion 231 is a groove recessed from the first surface in a direction away from the wall portion 2221. Along the first direction, the insulating member 23 has first and second surfaces arranged opposite each other. The relief portion 231 is a through hole extending through both the first and second surfaces.

[0136] The insulating member 23 includes an insulating plate 232 . The insulating plate 232 is disposed between the electrode assembly 21 and the wall portion 2221 along the first direction. The insulating plate 232 is provided with an escape portion 231 .

[0137] The insulating member 23 includes a covering body 233 that covers the electrode assembly 21 along its circumference. The covering body 233 is provided with a relief portion 231. The covering body 233 has a first covering portion 2331 and a second covering portion 2332 located between the electrode assembly 21 and the wall portion 2221. The first covering portion 2331 and the second covering portion 2332 are stacked along a first direction, with the first covering portion 2331 being closer to the wall portion 2221 than the second covering portion 2332. The relief portion 231 is provided on the first covering portion 2331.

[0138] The insulating part 23 of the battery cell 20 can not only insulate and isolate the electrode assembly 21 and the shell 22, but also has an avoidance portion 231 that can avoid the pressure relief mechanism 2222 at a position corresponding to the pressure relief mechanism 2222. Therefore, even if the insulating part 23 is in a vibration condition or is squeezed by the electrode assembly 21, it will not block the pressure relief mechanism 2222 or apply a large pressure, and will not affect the normal operation of the pressure relief mechanism 2222. When the pressure inside the battery cell 20 reaches the detonation pressure, the pressure relief mechanism 2222 can open normally without opening prematurely or delaying the opening, thereby ensuring the normal operation of the battery cell 20.

[0139] The avoidance portion 231 is a groove formed on the insulating member 23. The internal space of the groove can avoid the pressure relief mechanism 2222, so that the insulating member 23 will not contact the pressure relief mechanism 2222 under vibration conditions or when squeezed by the electrode assembly 21, and will not affect the normal operation of the pressure relief mechanism 2222, so that the pressure relief mechanism 2222 can open normally and realize the normal pressure relief function. In addition, since the avoidance portion 231 does not pass through the insulating member 23, the insulating member 23 can still insulate and isolate the electrode assembly 21 and the wall portion 2221 without the need to set up other insulating components. The avoidance portion 231 is a through hole that passes through the first and second surfaces of the insulating member 23 that are arranged oppositely in the first direction. The avoidance portion 231 is set as a through hole to ensure that sufficient avoidance space is formed to avoid the pressure relief mechanism 2222. Since the avoidance portion 231 is a through hole, it may affect the insulation performance of the insulating member 23. Therefore, an additional insulating component can be set to isolate the electrode assembly 21 and the wall portion 2221. The solution in which the avoidance portion 231 is a through hole can be applied to the case where the thickness of the portion of the insulating member 23 located between the electrode assembly 21 and the wall portion 2221 is relatively thin, so as to achieve a better avoidance effect.

[0140] The insulating plate 232 serves as a support for the electrode assembly 21, securing it within the housing 22. Under vibration conditions or when squeezed by the electrode assembly 21, the insulating plate 232 resists deformation, providing excellent insulation and support. A relief portion 231 is provided on the insulating plate 232 to prevent it from blocking the pressure relief mechanism 2222, thereby ensuring the pressure relief capability of the pressure relief mechanism 2222.

[0141] The covering body 233 can cover the circumference of the electrode assembly 21, and can better separate the electrode assembly 21 and the shell 22, thereby achieving a better insulation effect. A avoidance portion 231 is provided on the covering body 233 to prevent the covering body 233 from contacting the pressure relief mechanism 2222 under vibration conditions or when squeezed by the electrode assembly 21, thereby blocking the pressure relief mechanism 2222 and affecting the normal operation of the pressure relief mechanism 2222. The first covering portion 2331 and the second covering portion 2332 are stacked, and the first covering portion 2331 is the covering portion located on the outer layer. The first covering portion 2331 is easy to contact with the pressure relief mechanism 2222 and block the pressure relief mechanism 2222, so the avoidance portion 231 is provided on the first covering portion 2331 to achieve a better avoidance effect. At the same time, the second covering portion 2332 can still achieve a good insulation effect.

[0142] The above description is merely a preferred embodiment of the present application and is not intended to limit the present application. Various modifications and variations are possible for those skilled in the art. Any modifications, equivalent substitutions, or improvements made within the spirit and principles of the present application shall be included within the scope of protection of the present application.

Claims

1. A battery cell, characterized in that: include: electrode assembly; a housing for accommodating the electrode assembly, the housing having a wall portion disposed opposite to the electrode assembly along a first direction; a pressure relief mechanism, disposed on the wall; an insulating member, comprising a covering film and an insulating plate, wherein the covering film covers the electrode assembly along a circumferential direction of the electrode assembly, the insulating plate is located between the covering film and the wall portion, the covering film having a first covering portion and a second covering portion located between the electrode assembly and the insulating plate, the first covering portion and the second covering portion being stacked along the first direction, the first covering portion being closer to the wall portion than the second covering portion; The first covering portion is provided with an avoidance portion at a position corresponding to the pressure relief mechanism, the second covering portion is not provided with an avoidance portion, the insulating plate is provided with a through hole at a position corresponding to the pressure relief mechanism, and the avoidance portion and the through hole are used to avoid the pressure relief mechanism.

2. The battery cell according to claim 1, characterized in that: Along the first direction, a projection of the outline of the escape portion on the wall portion is arranged around the pressure relief mechanism.

3. The battery cell according to claim 2, characterized in that: Along the first direction, the first covering portion has a first surface facing the wall portion, and the avoidance portion is a groove recessed from the first surface along a direction away from the wall portion.

4. The battery cell according to claim 2, characterized in that: Along the first direction, the first covering portion has a first surface and a second surface that are oppositely arranged, and the avoiding portion is a through hole that passes through the first surface and the second surface.

5. The battery cell according to any one of claims 2 to 4, characterized in that: Along the length direction of the avoidance portion, the size of the avoidance portion is a1, and the size of the pressure relief mechanism is a2, satisfying: 0.1≤a2 / a1≤1.

6. The battery cell according to any one of claims 2 to 4, characterized in that: Along the width direction of the avoidance portion, the size of the avoidance portion is b1, and the size of the pressure relief mechanism is b2, satisfying: 0.05≤b2 / b1.

7. The battery cell according to claim 6, characterized in that: Along the width direction of the escape portion, the size b1 of the escape portion and the size b2 of the pressure relief mechanism further satisfy: b2 / b1≤5.

8. The battery cell according to any one of claims 2 to 4, characterized in that: Along the first direction, the depth of the avoidance portion is h, which satisfies 0.05 mm ≤ h ≤ 1 mm.

9. The battery cell according to any one of claims 2 to 4, characterized in that: Along the first direction, the projection area of ​​the electrode assembly on the wall portion is S1, and the area enclosed by the outline of the avoidance portion is S2, satisfying: 0.002<S2 / S1<0.

8.

10. The battery cell according to claim 1, characterized in that: The avoidance portion is a notch formed in the first covering portion.

11. A battery, characterized in that: include: Box; The battery cell according to any one of claims 1 to 10, wherein the battery cell is accommodated in the box.

12. An electrical device, characterized in that: Comprising the battery of claim 11.

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