A battery cell, a battery device, and an electrical device

Abstract

The present application discloses a battery cell, a battery device and an electrical device. The battery cell provided by the present application includes a housing and a deflation assembly. The housing includes a wall portion, and the wall portion is provided with an exhaust hole communicating the interior and the exterior of the housing. The wall portion includes a fixing portion, and the fixing portion is spaced from the exhaust hole. The deflation assembly is located inside the housing. The deflation assembly includes a shielding member and a falling body connected to the shielding member. The shielding member is connected to the wall portion and covers the exhaust hole. The falling body is fixedly connected to the fixing portion. Wherein, the falling body is separated from the fixing portion in a state where at least part of the fixing portion is melted, and at least part of the shielding member moves away from the wall portion under the action of the self-gravity of the falling body, so that the exhaust hole communicates with the interior of the housing. Thus, the fixing portion can be released from the fixing state with the falling body in a state where at least part of the fixing portion is melted, and the falling body moves away from the wall portion under the action of its own gravity, thereby driving at least part of the shielding member away from the wall portion, so that the exhaust hole is conducted to the interior of the housing, improving the exhaust efficiency of the battery cell.

Description

Technical Field

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

[0002] Energy conservation and emission reduction are the key to sustainable development, which has promoted the adjustment of energy structure and the development and application of battery technology. The key to the development of battery technology lies in electrochemical energy storage technology, which has been widely used in portable electronics, electric vehicles and energy storage systems due to its high energy density, good cycle capacity, high operating voltage, environmental protection and low self-discharge.

[0003] During the use of battery cells, gas will be generated inside the outer shell of the battery cells. When the gas production rate of the battery cells is much greater than the exhaust rate, gas is easily accumulated inside the outer shell, causing the battery cells to swell or even explode. Summary of the invention

[0004] The main purpose of the present application is to provide a battery cell, a battery device and an electrical device, aiming to solve the above-mentioned technical problems existing in the prior art.

[0005] To solve the above-mentioned problems, the present application provides a battery cell, which includes a shell and a venting assembly, the shell includes a wall portion, the wall portion is provided with an exhaust hole connecting the inside and outside of the shell, the wall portion includes a fixing portion, and the fixing portion is spaced apart from the exhaust hole; the venting assembly is located inside the shell, the venting assembly includes a shielding member and a falling body connected to the shielding member, the shielding member is connected to the wall portion and covers the exhaust hole, the falling body is fixedly connected to the fixing portion, wherein the falling body is separated from the fixing portion when the fixing portion is at least partially melted, and at least part of the shielding member is moved away from the wall portion under the action of the gravity of the falling body itself, so that the exhaust hole is connected to the inside of the shell. Thus, the fixing portion can fix the falling body in an unmelted state, so that the covering piece covers the exhaust hole, and the fixing portion can release the fixing state with the falling body when it is at least partially melted. The falling body moves away from the wall under the action of its own gravity, driving at least part of the covering piece away from the wall, so that the exhaust hole is connected with the inside of the shell, and the gas inside the shell can be discharged to the outside of the shell through the exhaust hole, thereby improving the exhaust efficiency of the battery cell and alleviating the risk of swelling or even explosion of the battery cell due to too low exhaust speed of the gas inside the shell.

[0006] In some embodiments, the blocking member includes a first member and a second member connected to each other. The first member is connected to the wall portion, and the second member is connected to the dropping body. At least one of the first member and the second member blocks the exhaust hole, and at least a part of the second member is configured to move away from the wall portion under the action of the self-gravity of the dropping body. Thus, by the cooperation of the first member and the fixing portion, the connection stability between the blocking member and the wall portion is improved in the state where the fixing portion is connected to the dropping body, so as to better block the exhaust hole. In the state where at least a part of the fixing portion is melted, at least a part of the second member moves away from the wall portion under the action of the self-gravity of the dropping body, so that the exhaust hole communicates with the inside of the housing, improving the exhaust efficiency of the battery cell.

[0007] In some embodiments, in the state where the dropping body is connected to the fixing portion, the second member blocks the exhaust hole. Thus, the exhaust hole can be blocked by the second member, facilitating the direct communication of the exhaust hole after the second member moves away from the wall portion under the action of the self-gravity of the dropping body, reducing the risk of failure in the communication of the exhaust hole, with a simple structure and improved exhaust efficiency of the battery cell.

[0008] In some embodiments, the first member is provided with a gas passage communicating with the exhaust hole. In the state where the dropping body is connected to the fixing portion, the second member blocks the gas passage, and in the state where the dropping body is separated from the fixing portion, the exhaust hole communicates with the inside of the housing through the gas passage. Thus, in the state where the dropping body is connected to the fixing portion, the gas passage on the first member can be blocked by the second member, further isolating the exhaust hole from the inside of the housing and reducing the risk of accidental communication between the inside and the outside of the housing through the exhaust hole. In the state where the dropping body is separated from the fixing portion, the exhaust hole and the inside of the housing can be communicated for exhaust by the second member moving away from the wall portion, improving the flexibility of the air release assembly.

[0009] In some embodiments, the blocking member includes an intermediate deformation portion connected between the first member and the second member. The intermediate deformation portion deforms under the action of the self-gravity of the dropping body to move at least a part of the second member away from the wall portion. Thus, the first member and the second member can be connected by the intermediate deformation portion, improving the connection stability between the first member and the second member in the state where the dropping body is connected to the fixing portion, and deforming in the state where the dropping body is separated from the fixing portion, facilitating at least a part of the second member to move away from the wall portion.

[0010] In some embodiments, the intermediate deformation portion has elasticity. Thus, by making the intermediate deformation portion elastic, in the state where the dropping body is separated from the fixing portion, the intermediate deformation portion is more likely to deform, reducing the obstruction of the intermediate deformation portion to the second member, further facilitating at least a part of the second member to move away from the wall portion and improving the reliability of the air release assembly.

[0011] In some embodiments, the wall portion includes an end cap and a lower plastic part. The lower plastic part is located inside the outer shell and is fixedly connected to the end cap. The fixing part is provided on the lower plastic part. Thus, by providing the fixing part on the lower plastic part, the structural stability of the fixing part in the unmelted state is improved. At the same time, there is no need to additionally provide a structure for supporting the fixing part inside the outer shell, and the structure is simple, saving costs.

[0012] In some embodiments, the battery cell includes a pressure relief valve. The pressure relief valve is provided on the wall portion and is spaced apart from the exhaust hole. Thus, when the gas content inside the outer shell is relatively high, the pressure relief valve and the air release assembly cooperate with each other, so as to better adjust the air pressure inside the outer shell, improve the exhaust efficiency of the battery cell, and further improve the reliability of the battery cell.

[0013] In some embodiments, the battery cell further includes two electrode posts. The pressure relief valve is located between the two electrode posts in the length direction of the wall portion. Thus, by arranging the pressure relief valve between the two electrode posts in the length direction of the wall portion, it is convenient for the pressure relief valve to release pressure more evenly when there is more gas inside the outer shell, improving the reliability of the battery cell.

[0014] In some embodiments, the number of the exhaust holes and the air release assemblies is multiple, and each air release assembly corresponds to an exhaust hole. Thus, by providing multiple exhaust holes and air release assemblies, the ability of the air release assemblies and the exhaust holes to adjust the air pressure inside the outer shell is further improved, and the exhaust efficiency of the battery cell is improved.

[0015] In some embodiments, the falling bodies of at least two air release assemblies are fixedly connected to a fixing part. Thus, by fixedly connecting the falling bodies of at least two air release assemblies to a fixing part, the falling bodies of at least two air release assemblies can be released when a fixing part is in at least partially melted state, reducing the number of fixing parts required and saving costs.

[0016] To solve the above problems, the present application further provides a battery device. The battery device includes a battery box and the above-mentioned battery cell, and the battery cell is arranged inside the battery box.

[0017] To solve the above problems, the present application further provides an electrical device. The electrical device includes the above-mentioned battery device. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] In order to more clearly illustrate the technical solutions in the embodiments of the present application or the prior art, the following will briefly introduce the drawings required to be used in the embodiments. Obviously, the drawings described below are only some embodiments of the present application. For those of ordinary skill in the art, other drawings can be obtained based on these drawings without creative efforts.

[0019] Figure 1It is a schematic structural diagram of a vehicle according to one or more embodiments of the present application;

[0020] Figure 2 It is an exploded structural schematic diagram of a battery device according to one or more embodiments of the present application;

[0021] Figure 3 It is an exploded structural schematic diagram of a battery cell according to one or more embodiments of the present application;

[0022] Figure 4 It is an exploded structural schematic diagram of a wall portion of a battery cell according to one or more embodiments of the present application;

[0023] Figure 5 It is a first perspective schematic diagram of a battery cell according to one or more embodiments of the present application;

[0024] Figure 6 It is a second perspective schematic diagram of a battery cell according to one or more embodiments of the present application;

[0025] Figure 7 It is a first structural schematic diagram of a battery cell with an unfused fixing portion according to one or more embodiments of the present application;

[0026] Figure 8 It is according to Figure 7 The structural schematic diagram after partial melting of the fixing portion of the battery cell shown;

[0027] Figure 9 It is a second structural schematic diagram of a battery cell with an unfused fixing portion according to one or more embodiments of the present application;

[0028] Figure 10 It is according to Figure 9 The structural schematic diagram after partial melting of the fixing portion of the battery cell shown.

[0029] Reference numerals: vehicle 1; battery device 2; controller 3; motor 4; battery box 20; first part 21; second part 22; battery cell 10; outer shell 100; wall portion 110; exhaust hole 111; fixing portion 112; end cap 113; lower plastic part 114; housing 120; air release assembly 200; shielding part 210; first component 211; gas channel 2111; second component 212; intermediate deformation part 213; dropping body 220; electrode assembly 300; pressure relief valve 400; electrode post 500. Detailed implementation manners

[0030] Hereinafter, embodiments of the technical solutions of the present application will be described in detail with reference to the drawings. The following embodiments are only used to illustrate the technical solutions of the present application more clearly, so they are only examples and cannot be used to limit the protection scope of the present application.

[0031] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the technical field to which this application belongs; the terms used herein are for the purpose of describing specific embodiments only and are not intended to limit this application; the terms "comprising" and "having" and any variations thereof in the specification and claims of this application and the above description of the drawings are intended to cover non-exclusive inclusion.

[0032] In the description of the embodiments of this application, technical terms such as "first" and "second" are only used to distinguish different objects and cannot be understood as indicating or implying relative importance or implicitly specifying the quantity, specific order or primary-secondary relationship of the indicated technical features. In the description of the embodiments of this application, the meaning of "a plurality of" is more than two, unless otherwise specifically defined.

[0033] Reference to "embodiment" herein means that a particular feature, structure or characteristic described in connection with the embodiment can be included in at least one embodiment of this application. The phrase appears in various places in the specification and does not necessarily refer to the same embodiment, nor is it an independent or alternative embodiment mutually exclusive with other embodiments. Those skilled in the art will explicitly and implicitly understand that the embodiments described herein can be combined with other embodiments.

[0034] In the description of the embodiments of this application, the term "and / or" is merely a description of the association relationship of associated objects, indicating that three relationships can 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 " / " herein generally represents an "or" relationship between the associated objects before and after.

[0035] In the description of the embodiments of this application, the term "a plurality of" means more than two (including two). Similarly, "a plurality of groups" means more than two groups (including two groups), and "a plurality of pieces" means more than two pieces (including two pieces).

[0036] In the description of the embodiments of this application, the orientation or positional relationship indicated by technical terms such as "center", "longitudinal", "transverse", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential", etc. is based on the orientation or positional relationship shown in the drawings, and is only for the convenience of describing the embodiments of this application and simplifying the description, rather than indicating or implying that the indicated device or element must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the embodiments of this application.

[0037] In the description of the embodiments of the present application, unless otherwise clearly defined and limited, technical terms such as "installation", "connection", "linkage", "fixation" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral one; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, and it can be the communication inside two components or the interaction relationship between two components. For those of ordinary skill in the art, the specific meanings of the above terms in the embodiments of the present application can be understood according to specific circumstances.

[0038] Currently, from the perspective of the development of the market situation, the application of batteries is becoming more and more extensive. Batteries are not only used in energy storage power systems such as hydropower, thermal power, wind power, and solar power plants, but also widely used in electric vehicles such as electric bicycles, electric motorcycles, and electric cars, as well as in multiple fields such as military equipment and aerospace. With the continuous expansion of the application fields of batteries, the market demand is also constantly increasing.

[0039] The batteries mentioned in this field can be divided into primary batteries and rechargeable batteries according to whether they can be recharged. Primary batteries are also called "throwaway" batteries and primary cells. Because after their power is exhausted, they cannot be recharged and used again and can only be discarded. Rechargeable batteries are also called secondary batteries or accumulators. The manufacturing materials and processes of rechargeable batteries are different from those of primary batteries. Their advantage is that they can be recycled multiple times after charging. The output current load capacity of rechargeable batteries is higher than that of most primary batteries. Currently, the common types of rechargeable batteries are: lead-acid batteries, nickel-metal hydride batteries, and lithium-ion batteries. Lithium-ion batteries have the advantages of light weight, large capacity (the capacity is 1.5 to 2 times that of nickel-metal hydride batteries of the same weight), no memory effect, etc., and have a very low self-discharge rate. Therefore, even though the price is relatively high, they are still widely used. Lithium-ion batteries are also widely used in pure electric vehicles and hybrid vehicles. The capacity of lithium-ion batteries used for this purpose is relatively slightly lower, but they have a large output and charging current and a long service life, but the cost is high.

[0040] The batteries described in the embodiments of the present application refer to rechargeable batteries or primary batteries. Hereinafter, lithium-ion batteries will be mainly used as an example to describe the embodiments disclosed in the present application. It should be understood that the embodiments disclosed in the present application are applicable to any other appropriate type of rechargeable battery. The batteries mentioned in the embodiments disclosed in the present application can be directly or indirectly applied to an appropriate device to supply power to the device.

[0041] The present application provides an electrical device, which may include but is not limited to mobile phones, tablets, laptop computers, electric toys, electric tools, battery cars, electric vehicles, ships, spacecraft, etc. Among them, the electric toys may include fixed or mobile electric toys, such as game consoles, electric vehicle toys, electric ship toys, electric aircraft toys, etc., and the spacecraft may include airplanes, rockets, space shuttles, spaceships, etc. Among them, the electrical device may include a battery device, and the electrical device can provide electrical energy through the battery device to achieve corresponding functions.

[0042] Taking the electrical device as an electric vehicle as an example, the electric vehicle may include a battery device.

[0043] Please refer to Figure 1 , Figure 1 which is a schematic structural diagram of a vehicle according to one or more embodiments of the present application.

[0044] 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 battery device 2 is arranged inside the vehicle 1, and the battery device 2 can be arranged at the bottom, head or tail of the vehicle 1. The battery device 2 can be used for power supply of the vehicle 1. For example, the battery device 2 can be used as the operating power source of the vehicle 1. The vehicle 1 may further include a controller 3 and a motor 4. The controller 3 is used to control the battery device 2 to supply power to the motor 4. For example, it is used for the working power requirements during the start, navigation and driving of the vehicle 1.

[0045] In some embodiments of the present application, the battery device 2 can not only be used as the operating power source of the vehicle 1, but also as the driving power source of the vehicle 1, replacing or partially replacing fuel or natural gas to provide driving power for the vehicle 1.

[0046] In order to improve the performance of the electrical device, the present application also provides a battery device. Refer to Figure 2 , Figure 2 which is an exploded structural schematic diagram of a battery device according to one or more embodiments of the present application.

[0047] The shape of the battery device 2 may include but is not limited to square, cylindrical or any other shape.

[0048] In some embodiments, the battery device 2 includes a battery box 20 and battery cells 10, and the battery cells 10 are disposed within the battery box 20. The battery box 20 is configured to provide a receiving space for the battery cells 10, and the battery box 20 may adopt various structures. In some embodiments, the battery box 20 may include a first part 21 and a second part 22, the first part 21 and the second part 22 are covered with each other, and the first part 21 and the second part 22 together define a receiving space 130 for accommodating the battery cells. The second part 22 may be a hollow structure with an open end, and the first part 21 may be a plate-like structure. The first part 21 is covered on the open side of the second part 22 so that the first part 21 and the second part 22 together define the receiving space; the first part 21 and the second part 22 may also both be hollow structures with an open side, and the open side of the first part 21 is covered on the open side of the second part 22.

[0049] In the battery device 2, there may be multiple battery cells 10, and the multiple battery cells 10 may be connected in series, parallel, or in a combined series-parallel connection. A combined series-parallel connection means that there are both series and parallel connections among the multiple battery cells 10. The multiple battery cells 10 may be directly connected in series, parallel, or in a combined series-parallel connection together, and then the whole formed by the multiple battery cells 10 is accommodated within the battery box 20; of course, the battery device 2 may also be such that multiple battery cells 10 are first connected in series, parallel, or in a combined series-parallel connection to form a battery module form, and then multiple battery modules are connected in series, parallel, or in a combined series-parallel connection to form a whole and are accommodated within the battery box 20. The battery device 2 may further include other structures. For example, the battery device 2 may further include a busbar component for realizing the electrical connection among the multiple battery cells 10.

[0050] The manufacturing methods of the battery cells 10 include a stacking type and a winding type, that is, the battery cells 10 are divided into two types: stacked batteries and wound batteries. Stacked batteries have a uniform current collection effect, a relatively small internal resistance of the battery, and a large specific power. However, in order to improve the accuracy, extremely high requirements are imposed on the mold accuracy, the equipment investment is high, and the process is relatively complex, resulting in low production efficiency. Wound batteries are simple to manufacture, and the requirements for equipment accuracy in the processes of making the battery plates and assembling are generally low, with high production efficiency and low cost. In terms of performance, wound batteries have excellent high and low temperature performance, can be charged very quickly, have an extremely long service life, a stable high output voltage, and a strong and earthquake-resistant structure.

[0051] The battery cell 10 refers to the smallest unit that makes up the battery device 2. The battery cell 10 may include a shell, an electrode assembly, and other functional components. The shell can form an internal environment of the battery cell 10 and isolate the internal environment of the battery cell 10 from the external environment. It is understandable that the shell can provide support and protection for the components in the internal environment of the battery cell 10. The electrode assembly is a component in the battery cell 10 where electrochemical reactions occur. One or more electrode assemblies may be included in the shell. The electrode assembly is mainly formed by winding or stacking positive and negative electrode sheets, and an isolation member is usually provided between the positive and negative electrode sheets.

[0052] During the use of the battery cell 10 , when the gas generation rate of the battery cell 10 is much greater than the gas exhaust rate, the gas is easily accumulated inside the shell, causing the battery cell 10 to swell or even explode.

[0053] In order to solve the technical problems existing in the related art, the present application provides a battery cell, a battery device and an electric device. The battery cell has a gas release assembly located inside a shell, a falling body in the gas release assembly is connected to a fixed part on the shell wall, and when the fixed part is at least partially melted, the falling body drives at least part of the shielding member away from the wall under the action of its own gravity, thereby connecting the exhaust hole on the wall and the inside of the shell, thereby improving the exhaust efficiency of the battery cell.

[0054] Specifically, see Figures 3 - 6 , Figure 3 is a schematic diagram of an exploded structure of a battery cell according to one or more embodiments of the present application; Figure 4 is a schematic diagram of an exploded structure of a wall portion of a battery cell according to one or more embodiments of the present application; Figure 5 is a schematic diagram of a battery cell from a first perspective according to one or more embodiments of the present application; Figure 6 is a schematic diagram of a battery cell from a second perspective according to one or more embodiments of the present application.

[0055] The battery cell 10 includes a shell 100 and a venting assembly 200, the shell 100 includes a wall portion 110, the wall portion 110 is provided with an exhaust hole 111 connecting the inside and outside of the shell 100, the wall portion 110 includes a fixing portion 112, and the fixing portion 112 is spaced apart from the exhaust hole 111; the venting assembly 200 is located inside the shell 100, the venting assembly 200 includes a shielding member 210 and a falling body 220 connected to the shielding member 210, the shielding member 210 is connected to the wall portion 110 and covers the exhaust hole 111, the falling body 220 is fixedly connected to the fixing portion 112, wherein the falling body 220 is separated from the fixing portion 112 when the fixing portion 112 is at least partially melted, and at least part of the shielding member 210 is away from the wall portion 110 under the action of the gravity of the falling body 220 itself, so that the exhaust hole 111 is connected to the inside of the shell 100.

[0056] The housing 100 includes a wall portion 110. Exemplarily, when the housing 100 is square-shaped, the wall portion 110 can be any one of the six side walls of the housing 100. The wall portion 110 is provided with an exhaust hole 111 that communicates the inside and the outside of the housing 100. In some application scenarios, the gas inside the housing 100 can be discharged to the outside of the housing 100 through the exhaust hole 111. The wall portion 110 includes a fixing portion 112, and the fixing portion 112 can be made of a material with a relatively low melting point. It should be noted that when the gas content inside the housing 100 is relatively high, the temperature inside the housing 100 will gradually rise. When the temperature inside the housing 100 rises to the melting point of the fixing portion 112, at least a part of the fixing portion 112 will melt, so that the structure of the fixing portion 112 fails. It can be understood that the air leakage assembly 200 covers the exhaust hole 111 through the shielding member 210, so that the exhaust hole 111 and the inside of the housing 100 can be isolated through the shielding member 210 in a state where the structure of the fixing portion 112 has not failed, reducing the risk of substances inside and outside the housing 100 passing through the exhaust hole 111 during the normal operation of the battery cell 10. When the gas content inside the housing 100 is relatively high, so that the temperature inside the housing 100 rises, causing at least a part of the fixing portion 112 to melt, the fixing portion 112 can no longer maintain the support and connection of the falling body 220. The falling body 220 will move away from the wall portion 110 under the action of its own gravity, and drive at least a part of the shielding member 210 away from the wall portion 110, so that the exhaust hole 111 communicates with the inside of the housing 100, and then facilitates the discharge of the gas inside the housing 100 to the outside of the housing 100 through the exhaust hole 111. Among them, the falling body 220 has a certain mass, and its mass is sufficient to drive at least a part of the shielding member 210 to fall. Exemplarily, the falling body 220 can be of any shape. Optionally, the falling body 220 can include, but is not limited to, insulating objects, etc. Specifically, the falling body 220 can be a metal sphere. Further, the connection manner between the shielding member 210 and the wall portion 110 can include, but is not limited to, welding, etc. Exemplarily, at least a part of the shielding member 210 can be welded to the wall portion 110 with a relatively small bonding force, and the gravity received by the falling body 220 can be greater than the bonding force between the shielding member 210 and the wall portion 110, so as to facilitate the falling body 220 to drive at least a part of the shielding member 210 away from the wall portion 110.

[0057] Through the above-described embodiments, the fixing portion 112 can fix the falling body 220 in an unmelted state, so that the shielding member 210 covers the exhaust hole 111, and in a state where at least part of the fixing portion 112 is melted, the fixing portion 112 releases the fixing state with the falling body 220. Under the action of its own gravity, the falling body 220 moves away from the wall portion 110, driving at least part of the shielding member 210 away from the wall portion 110, so that the exhaust hole 111 communicates with the inside of the housing 100. The gas inside the housing 100 can then be discharged to the outside of the housing 100 through the exhaust hole 111, improving the exhaust efficiency of the battery cell 10 and alleviating the risk that the battery cell 10 bulges or even explodes due to the too low exhaust speed of the gas inside the housing 100.

[0058] In some embodiments, the shielding member 210 includes a first member 211 and a second member 212 that are connected to each other. The first member 211 is connected to the wall portion 110, and the second member 212 is connected to the falling body 220. At least one of the first member 211 and the second member 212 shields the exhaust hole 111, and at least a part of the second member 212 is configured to move away from the wall portion 110 under the action of the self-gravity of the falling body 220. In some application scenarios, the second member 212 may extend in the direction in which the first member 211 and the fixing portion 112 are spaced apart. In a state where the falling body 220 is connected to the fixing portion 112, the first member 211 can be used to fix one end of the second member 212, and the fixing portion 112 can fix the other end of the second member 212 through the falling body 220, thereby improving the installation stability of the second member 212. However, it should be noted that the connection manner between the falling body 220 and the second member 212 can be a rigid connection or a flexible connection. When the connection manner between the falling body 220 and the second member 212 is a flexible connection, for example, when the second member 212 is connected to the falling body 220 through a flexible wire harness, the first member 211 can provide certain fixation and support for the second member 212. In some embodiments, the first member 211 can be fixedly connected to the wall portion 110 and movably connected to the second member 212, that is, in a state where the falling body 220 is connected to or separated from the fixing portion 112, the first member 211 can be relatively fixed to the wall portion 110. In a state where the falling body 220 is connected to the fixing portion 112, the second member 212 can be fixed relative to the first member 211 and the wall portion 110. In a state where the falling body 220 is separated from the fixing portion 112, at least a part of the second member 212 can change its position and posture, such as translation and rotation, relative to the first part 21 and the wall portion 110 under the action of the self-gravity of the falling body 220, so as to move away from the wall portion 110. In a state where the falling body 220 is connected to the fixing portion 112, the second member 212 can be directly connected to the wall portion 110 or indirectly connected to the wall portion 110 through the first member 211. Exemplarily, both the first member 211 and the second member 212 can be connected to the wall portion 110 by means including but not limited to welding. Taking welding as an example, the welding bonding force between the first member 211 and the wall portion 110 can be set to be relatively large, and the welding bonding force between the second member 212 and the wall portion 110 can be set to be relatively small. The gravity received by the falling body 220 can be greater than the bonding force between the second member 212 and the wall portion 110 and less than the bonding force between the first member 211 and the wall portion 110, so as to facilitate the falling body 220 to drive the second member 212 to separate from the wall portion 110, while preventing the first member 211 from separating from the wall portion 110. In some application scenarios, the exhaust hole 111 can be shielded by the first member 211 alone, or by the second member 212 alone, or by the first member 211 and the second member 212 in cooperation with each other to shield the exhaust hole 111.Thus, by the cooperation of the first component 211 and the fixing part 112, in the state where the fixing part 112 is connected to the falling body 220, the connection stability between the shielding part 210 and the wall part 110 is improved, so as to better block the exhaust hole 111. In the state where at least part of the fixing part 112 is melted, at least part of the second component 212 moves away from the wall part 110 under the action of the self-gravity of the falling body 220, so that the exhaust hole 111 is communicated with the inside of the housing 100, and the exhaust efficiency of the battery cell 10 is improved.

[0059] In some embodiments, the wall part 110 includes an end cap 113 and a lower plastic part 114. The lower plastic part 114 is located inside the housing 100 and is fixedly connected to the end cap 113, and the fixing part 112 is arranged on the lower plastic part 114. The housing 100 may include a housing body 120 and an end cap 113. The end cap 113 refers to a component that covers the opening of the housing body 120 to isolate the internal environment of the battery cell 10 from the external environment. Without limitation, the shape of the end cap 113 may be adapted to the shape of the housing body 120 to cooperate with the housing body 120. Optionally, the end cap 113 may be made of a material with certain hardness and strength (such as aluminum alloy). In this way, the end cap 113 is not easily deformed when being squeezed or collided, so that the battery cell 10 can have higher structural strength and the safety performance can also be improved. Functional components such as electrode terminals may be arranged on the end cap 113. The electrode terminals can be used for electrically connecting with the electrode assembly 300 to output or input the electric energy of the battery cell 10. In some embodiments, the electrode terminals may include pole columns. The pole columns may include a positive pole column and a negative pole column for current output and connection with an external circuit. In some embodiments, an explosion-proof part for releasing the internal pressure when the internal pressure or temperature of the battery cell 10 reaches a threshold value may also be arranged on the end cap 113. The material of the end cap 113 may include but is not limited to copper, iron, aluminum, stainless steel, aluminum alloy, plastic, etc. In some embodiments, an insulating part may also be arranged on the inner side of the end cap 113. The insulating part can be used to isolate the electrical connection components inside the housing body 120 from the end cap 113 to reduce the risk of short circuit. Exemplarily, the insulating part may be plastic, rubber, etc.

[0060] The housing 120 is a component for cooperating with the end cap 113 to form the internal environment of the battery cell 10. Among them, the formed internal environment can be used to accommodate the electrode assembly 300, the electrolyte, and other components. The housing 120 and the end cap 113 can be independent components. An opening can be provided on the housing 120, and the end cap 113 is covered at the opening to form the internal environment of the battery cell 10. Without limitation, the end cap 113 and the housing 120 can also be integrated. Specifically, the end cap 113 and the housing 120 can first form a common connection surface before other components are put into the housing. When it is necessary to encapsulate the inside of the outer shell 100, the end cap 113 is then covered on the housing 120. The housing 120 can be of various shapes and sizes, such as cuboid, cylindrical, hexagonal prism, etc. Specifically, the shape of the housing 120 can be determined according to the specific shape and size of the electrode assembly 300. The material of the housing 120 can include but is not limited to copper, iron, aluminum, stainless steel, aluminum alloy, plastic, etc.

[0061] The lower plastic part 114 can be attached to the side of the end cap 113 facing the inside of the outer shell 100. The lower plastic part 114 can be integrally preformed from plastic or assembled from plastic components. The material of the lower plastic part 114 can include insulating materials. The lower plastic part 114 can provide insulation performance and improve the electrical insulation between the inside of the outer shell 100 and the wall part 110. In addition, the lower plastic part 114 can also play a role in fixing and protecting the electrode assembly 300 inside the outer shell 100, reducing the risk of open circuit caused by the displacement of components such as the electrode assembly 300 inside the outer shell 100 during the transportation and use of the battery cell 10, especially in a vibration environment. The connection method between the lower plastic part 114 and the wall part 110 includes but is not limited to welding, bonding, or snap connection, etc. Specifically, the fixing part 112 can be provided on the side of the lower plastic part 114 facing away from the end cap 113, so as to facilitate the connection between the fixing part 112 and the falling body 220. Thus, by arranging the fixing part 112 on the lower plastic part 114, the structural stability of the fixing part 112 in the unmelted state is improved, and at the same time, there is no need to additionally arrange a structure for supporting the fixing part 112 inside the outer shell 100, with a simple structure and cost savings.

[0062] In some embodiments, the shielding member 210 includes an intermediate deformation portion 213. The intermediate deformation portion 213 is connected between the first member 211 and the second member 212. The intermediate deformation portion 213 deforms under the action of the self-gravity of the falling body 220 so that at least a part of the second member 212 moves away from the wall portion 110. Exemplarily, the intermediate deformation portion 213 may include, but is not limited to, a thin film, a spring, and the like. It can be understood that the first member 211 and the second member 212 are connected to each other through the intermediate deformation portion 213, so that the second member 212 is more likely to undergo changes in position and posture such as translation or rotation relative to the first member 211, thereby facilitating at least the second member 212 to move away from the wall portion 110 under the drive of the falling body 220. Thus, the first member 211 and the second member 212 can be connected through the intermediate deformation portion 213 to improve the connection stability between the first member 211 and the second member 212 when the falling body 220 is connected to the fixing portion 112, and deform when the falling body 220 is separated from the fixing portion 112, so as to facilitate at least a part of the second member 212 to move away from the wall portion 110.

[0063] In some embodiments, the intermediate deformation portion 213 has elasticity. Exemplarily, the intermediate deformation portion 213 may be, but is not limited to, a spring, a spring piece, and the like. Specifically, taking the intermediate deformation portion 213 as a spring as an example, one end of the spring can be sleeved on the first member 211, and the other end of the spring can be sleeved on the second member 212. In a state where the falling body 220 is separated from the fixing portion 112, the middle part of the spring can be bent under the action of the self-gravity of the falling body 220, so that the second member 212 moves away from the wall portion 110. Thus, by making the intermediate deformation portion 213 elastic, in a state where the falling body 220 is separated from the fixing portion 112, the intermediate deformation portion 213 is more likely to deform, reducing the obstruction of the intermediate deformation portion 213 to the second member 212, further facilitating at least a part of the second member 212 to move away from the wall portion 110, and improving the reliability of the air leakage component 200.

[0064] In some embodiments, the number of the exhaust holes 111 and the air leakage components 200 is multiple, and each air leakage component 200 corresponds to an exhaust hole 111. Exemplarily, the number of the exhaust holes 111 may be two, three, four or more, and the number of the air leakage components 200 may also be two, three, four or more. Thus, by providing a plurality of exhaust holes 111 and air leakage components 200, the adjustment ability of the air leakage components 200 and the exhaust holes 111 to the internal air pressure of the housing 100 is further improved, and the exhaust efficiency of the battery cell 10 is improved.

[0065] In some embodiments, the falling bodies 220 of at least two air release components 200 are fixedly connected to a fixing part 112. The falling bodies 220 of two, three, four or more air release components 200 can be fixedly connected to a fixing part 112. Exemplarily, taking the falling bodies 220 of two air release components 200 being fixedly connected to a fixing part 112 as an example, the two air release components 200 can be respectively located on both sides of a fixing part 112, so that the falling bodies 220 of the two air release components 200 are respectively connected to both ends of the fixing part 112. Specifically, the two air release components 200 can be mirror-symmetrical with respect to the fixing part 112. Thus, by fixedly connecting the falling bodies 220 of at least two air release components 200 to a fixing part 112, the fixing part 112 can release the falling bodies 220 of at least two air release components 200 in at least a partially melted state, reducing the number of fixing parts 112 to be provided and saving costs.

[0066] In some embodiments, the battery cell 10 includes a pressure relief valve 400, and the pressure relief valve 400 is disposed on the wall portion 110 and is spaced apart from the exhaust hole 111. The pressure relief valve 400 can be used to release the internal pressure when the internal pressure or temperature of the battery cell 10 reaches a threshold. Exemplarily, during multiple charge and discharge cycles of the battery cell 10, gas may be generated inside the housing 100 of the battery cell 10 due to side reactions of the electrochemical reaction. As the gas content increases, the air pressure inside the housing 100 also increases. The increase in the air pressure inside the housing 100 easily causes the housing 100 of the battery cell 10 to deform and easily causes the structural strength of the housing 100 to fail. When the internal pressure of the battery cell 10 reaches the threshold, the inside of the housing 100 can be depressurized through the pressure relief valve 400. It can be understood that the pressure relief valve 400 and the air release component 200 can cooperate with each other to jointly discharge the gas inside the housing 100 to the outside of the housing 100 when the gas content inside the housing 100 is relatively high. Thus, when the gas content inside the housing 100 is relatively high, the pressure relief valve 400 and the air release component 200 can cooperate with each other to better adjust the air pressure inside the housing 100, improve the exhaust efficiency of the battery cell 10, and further improve the reliability of the battery cell 10.

[0067] In some embodiments, the battery cell 10 further includes two electrode posts 500, and the pressure relief valve 400 is located between the two electrode posts 500 in the length direction of the wall portion 110. One of the two electrode posts 500 is a positive electrode post and the other is a negative electrode post. The positive electrode post and the negative electrode post are disposed on the wall portion 110. The pressure relief valve 400 is located between the two electrode posts 500 in the length direction of the wall portion 110. Specifically, the pressure relief valve 400 may be located at the midpoint of the line connecting the two electrode posts 500 in the length of the wall portion 110. When gas is generated inside the outer casing 100, the gas may be more likely to accumulate between the two electrode posts 500. The pressure relief valve 400 is located between the two electrode posts 500, which facilitates the pressure relief valve 400 to better detect the pressure change inside the outer casing 100, so as to release the pressure more evenly. Thus, by arranging the pressure relief valve 400 between the two electrode posts 500 in the length direction of the wall portion 110, it is convenient for the pressure relief valve 400 to release the pressure more evenly when there is more gas inside the outer casing 100, improving the reliability of the battery cell 10.

[0068] Combined with Figures 7 - 8 , Figure 7 is a first schematic structural view of the non-melted fixing portion of the battery cell according to one or more embodiments of the present application; Figure 8 is according to Figure 7 the schematic structural view of the battery cell shown after partial melting of the fixing portion.

[0069] In some embodiments, when the falling body 220 is in a state of being connected to the fixing portion 112, the second component 212 blocks the exhaust hole 111. It can be understood that the second component 212 directly blocks the exhaust hole 111. In a state where the falling body 220 is separated from the fixing portion 112, at least a part of the second component 212 is away from the wall portion 110, and the exhaust hole 111 can be directly conducted, and the structure is relatively simple. Thus, the exhaust hole 111 can be blocked by the second component 212, which facilitates the second component 212 to directly conduct the exhaust hole 111 after moving away from the wall portion 110 under the action of its own gravity, alleviating the risk of failure in conducting the exhaust hole 111, with a simple structure and improving the exhaust efficiency of the battery cell 10.

[0070] Combined with Figures 9 - 10 , Figure 9 is a second schematic structural view of the non-melted fixing portion of the battery cell according to one or more embodiments of the present application; Figure 10 is according to Figure 9 the schematic structural view of the battery cell shown after partial melting of the fixing portion.

[0071] In some embodiments, the first component 211 is provided with a gas passage 2111. The gas passage 2111 communicates with the exhaust hole 111. When the falling body 220 is in a state of being connected to the fixing portion 112, the second component 212 blocks the gas passage 2111. When the falling body 220 is separated from the fixing portion 112, the exhaust hole 111 communicates with the interior of the housing 100 through the gas passage 2111. Exemplarily, the gas passage 2111 may be formed inside the first component 211 and exposed at one end of the first component 211 facing the second component 212 through an opening. When the falling body 220 is in a state of being connected to the fixing portion 112, the second component 212 may be located at the opening of the gas passage 2111 to block the gas passage 2111. When the falling body 220 is separated from the fixing portion 112, the second component 212 is driven away from the wall portion 110 by the falling body 220, so that the gas passage 2111 is exposed inside the housing 100, and then the exhaust hole 111 and the interior of the housing 100 are conducted through the gas passage 2111, facilitating the release of the gas inside the housing 100 to the outside of the housing 100 through the exhaust hole 111. Thus, when the falling body 220 is in a state of being connected to the fixing portion 112, the gas passage 2111 on the first component 211 can be blocked by the second component 212, thereby isolating the exhaust hole 111 and the interior of the housing 100, and reducing the risk of accidental communication between the interior and the exterior of the housing 100 through the exhaust hole 111. When the falling body 220 is separated from the fixing portion 112, the exhaust hole 111 and the interior of the housing 100 can be conducted by the second component 212 moving away from the wall portion 110 for exhaust, improving the flexibility of the air release assembly 200.

[0072] In summary, the battery cell 10 provided in the present application includes a housing 100 and a deflation assembly 200. The housing 100 includes a wall portion 110, and the wall portion 110 is provided with an exhaust hole 111 that communicates the inside and the outside of the housing 100. The wall portion 110 includes a fixing portion 112, and the fixing portion 112 is spaced from the exhaust hole 111. The deflation assembly 200 is located inside the housing 100. The deflation assembly 200 includes a shielding member 210 and a falling body 220 connected to the shielding member 210. The shielding member 210 is connected to the wall portion 110 and covers the exhaust hole 111. The falling body 220 is fixedly connected to the fixing portion 112. Wherein, the falling body 220 is separated from the fixing portion 112 in a state where at least part of the fixing portion 112 is melted, and at least part of the shielding member 210 moves away from the wall portion 110 under the action of the self-gravity of the falling body 220, so that the exhaust hole 111 communicates with the inside of the housing 100. Thus, the fixing portion 112 can fix the falling body 220 in an unmelted state, so that the shielding member 210 covers the exhaust hole 111, and in a state where at least part of the fixing portion 112 is melted, the fixing portion 112 releases the fixed state with the falling body 220. The falling body 220 moves away from the wall portion 110 under the action of its own gravity, driving at least part of the shielding member 210 away from the wall portion 110, so that the exhaust hole 111 is conducted with the inside of the housing 100, and the gas inside the housing 100 can be discharged to the outside of the housing 100 through the exhaust hole 111, improving the exhaust efficiency of the battery cell 10 and alleviating the risk that the battery cell 10 bulges or even explodes due to the too low gas discharge speed inside the housing 100. Compared with other types of battery cells, the battery cell 10 of the present application has higher exhaust efficiency and higher reliability.

[0073] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present application, rather than to limit them; although the present application has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that they can still modify the technical solutions described in the foregoing embodiments, or perform equivalent replacements on some or all of the technical features; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the scope of the technical solutions of the embodiments of the present application, and they should all be covered by the scope of the claims and the specification of the present application. In particular, as long as there is no structural conflict, the technical features mentioned in each embodiment can be combined in any way. The present application is not limited to the specific embodiments disclosed in the text, but includes all technical solutions falling within the scope of the claims.

Claims

1. A battery cell, characterized in that: The battery cell comprises: The housing comprises a wall portion, the wall portion is provided with an exhaust hole communicating the interior and the exterior of the housing, the wall portion comprises a fixing portion, the fixing portion is spaced apart from the exhaust hole; a deflation assembly, located inside the shell, comprising a shielding member and a falling body connected to the shielding member, the shielding member being connected to the wall portion and covering the exhaust hole, the falling body being fixedly connected to the fixing portion, wherein the falling body is separated from the fixing portion when the fixing portion is at least partially melted, and at least a portion of the shielding member is moved away from the wall portion under the action of the gravity of the falling body itself, so that the exhaust hole is connected to the inside of the shell; The shielding member includes a first component and a second component connected to each other, the first component is connected to the wall portion, the second component is connected to the falling body, at least one of the first component and the second component shields the exhaust hole, and at least a portion of the second component is used to move away from the wall portion under the action of the falling body's own gravity.

2. The battery cell according to claim 1, characterized in that: When the falling body is connected to the fixing portion, the second component covers the exhaust hole.

3. The battery cell according to claim 1, characterized in that: The first component is provided with a gas channel, and the gas channel is connected to the exhaust hole. When the falling body is connected to the fixed part, the second component blocks the gas channel. When the falling body is separated from the fixed part, the exhaust hole is connected to the inside of the shell through the gas channel.

4. The battery cell according to claim 1, characterized in that: The shielding member includes an intermediate deformation portion, which is connected between the first component and the second component. The intermediate deformation portion is deformed under the action of the gravity of the falling body so that at least a part of the second component is away from the wall.

5. The battery cell according to claim 4, characterized in that: The intermediate deformation portion has elasticity.

6. The battery cell according to claim 1, characterized in that: The wall portion includes an end cover and a lower plastic piece, wherein the lower plastic piece is located inside the shell and fixedly connected to the end cover, and the fixing portion is arranged on the lower plastic piece.

7. The battery cell according to claim 1, characterized in that: The battery cell includes a pressure relief valve disposed on the wall portion and spaced apart from the exhaust hole.

8. The battery cell according to claim 7, characterized in that: The battery cell further includes two electrode columns, and the pressure relief valve is located between the two electrode columns in the length direction of the wall portion.

9. The battery cell according to any one of claims 1 to 8, characterized in that: There are multiple exhaust holes and multiple air leaking components, and each air leaking component corresponds to one exhaust hole.

10. The battery cell according to claim 9, characterized in that: The falling bodies of at least two of the deflation assemblies are fixedly connected to one of the fixing parts.

11. A battery device, characterized in that: The battery device comprises a battery box and a battery cell according to any one of claims 1 to 10, wherein the battery cell is arranged in the battery box.

12. An electrical device, characterized in that: The electrical device comprises the battery device as claimed in claim 11.

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