Battery monomer, battery device and electric equipment

Abstract

The utility model relates to a battery monomer, a battery device and electric equipment, in the battery monomer, a shell is designed into a main body part and an end body part, and a pressure relief mechanism is arranged at the end body part, so that the battery monomer can be subjected to pressure relief at the end part of the shell when the battery monomer is out of control. Meanwhile, the area S1 of the section of at least part of the interior of the end body part is larger than the area S2 of the section of the interior of the main body part, so that more space is reserved at the end part of the shell. Therefore, when the single battery is in thermal runaway, the end part of the shell can accommodate more flue gas generated during runaway, the impact of the flue gas on the shell is relieved, the probability that the shell of the single battery is cracked during thermal runaway is effectively reduced, normal pressure relief when the single battery is out of control is realized, and the reliability of the single battery is improved.

Description

Technical Field

[0001] The present application relates to the field of battery technology, and in particular to battery cells, battery devices and electrical equipment. Background Art

[0002] With the rapid development of battery technology, the requirements for battery reliability have also increased. However, due to the limitations of the structural design of traditional batteries, when thermal runaway occurs, the battery shell is prone to bursting, resulting in reduced battery reliability. Utility Model Content

[0003] Based on this, it is necessary to provide a battery cell, a battery device and an electrical device to reduce the probability of shell explosion during thermal runaway and improve the reliability of the battery cell.

[0004] In the first aspect, the present application provides a battery cell, which includes: a shell; an electrode assembly accommodated in the shell; and a pressure relief mechanism for relieving pressure in the shell; wherein the shell includes a main body and an end body provided at at least one end of the main body along a preset direction, the pressure relief mechanism is provided at the end body, the main body has a first chamber for accommodating the electrode assembly, the end body has a second chamber connected to the first chamber, and along a direction perpendicular to the preset direction, the cross-sectional area S1 of at least part of the second chamber is greater than the cross-sectional area S2 of the first chamber.

[0005] The battery cell described above has a shell designed as a main body and an end body, and a pressure relief mechanism is arranged at the end body, which is conducive to achieving pressure relief of the battery cell at the end of the shell when out of control. At the same time, the cross-sectional area S1 of at least part of the interior of the end body is larger than the cross-sectional area S2 of the interior of the main body, so that more space is reserved at the end of the shell. In this way, when the battery cell has thermal runaway, the shell can accommodate more smoke generated during the runaway, reduce the impact of the smoke on the shell, improve the effectiveness of the smoke flowing to the end of the shell, and effectively reduce the probability of the shell of the battery cell bursting during thermal runaway, which is conducive to the stable pressure relief of smoke from the pressure relief mechanism and improves the reliability of the battery cell.

[0006] In some embodiments, the cross-sectional area S1 of the second chamber of at least one end body increases from the end of the second chamber close to the first chamber to the end of the second chamber away from the first chamber. In this design, the cross-sectional area inside the end body increases in a preset direction, providing more space to alleviate the impact of smoke and reducing the shell from bursting due to excessive pressure.

[0007] In some embodiments, the cross-sectional area S1 of the second chamber of at least one end body portion is kept consistent from the end of the second chamber close to the first chamber to the end of the second chamber away from the first chamber. In this way, the interior of the end body portion is designed as a uniform cross-sectional structure, so that the cross-sectional area of ​​the interior of the end body portion is larger than the cross-sectional area of ​​the main body portion in a preset direction, which greatly increases the exhaust space at the end of the shell, and effectively reduces the probability of the shell bursting due to excessive pressure.

[0008] In some embodiments, the length of the end body along the preset direction is recorded as L1, and the length of the shell along the preset direction is recorded as L0, wherein 1 / 12≤L1 / L0<1 / 2. With such a design, the ratio of the length of the end body to the length of the shell is controlled between 1 / 12 and 1 / 2, and the overall size of the battery cell is reduced while satisfying the effective space at the end of the shell, which is conducive to improving the installation space utilization of the battery cell.

[0009] In some embodiments, L1 / L0 also satisfies the condition: 1 / 10≤L1 / L0≤1 / 5. With such a design, the ratio of the length of the end body to the length of the shell is controlled between 1 / 10 and 1 / 5, further effectively taking into account the space at the end of the shell and the overall size of the battery cell.

[0010] In some embodiments, L0 satisfies the condition: 50mm≤L0≤300mm. With such a design, the length of the shell is controlled between 50mm and 300mm, and a battery cell of a reasonable length is obtained, so that smoke can effectively reach the end body when out of control, reducing the risk of shell explosion.

[0011] In some embodiments, the cross section of the second chamber of the end body in a vertical preset direction is configured as a circular structure, and the first chamber is configured as a cylindrical structure, and the preset direction is consistent with the axial direction of the main body. Such a design makes it easy to leave more space for the end of the cylindrical battery and reduce the risk of the shell of the cylindrical battery exploding when it loses control.

[0012] In some embodiments, the maximum diameter of the second chamber is recorded as D1, and the maximum diameter of the first chamber is recorded as D0, wherein D1 / D0≥1.05. In this design, the ratio of the maximum diameter of the second chamber to the maximum diameter of the first chamber is controlled to be above 1.05, so that the internal space of the end body is increased, and the risk of the shell bursting when out of control is reduced.

[0013] In some embodiments, D1 / D0 also satisfies the condition: D1 / D0≤1.3. In this design, the ratio of the maximum diameter of the second chamber to the maximum diameter of the first chamber is limited to within 1.3, and the diameter size of the end body is controlled as much as possible while reducing the risk of explosion of the shell in thermal runaway.

[0014] In some embodiments, the condition that D0 satisfies is: 10 mm ≤ D0 ≤ 80 mm. With such a design, the maximum diameter of the first chamber is controlled between 10 mm and 80 mm, and a cylindrical battery cell of suitable size is obtained.

[0015] In some embodiments, the end body includes two, and the two end body parts are respectively arranged at the two ends of the main body along the preset direction. In this design, the end body parts are respectively arranged at the two ends of the main body, so that the internal space of the two ends of the shell is increased, and the impact of smoke on the shell during thermal runaway is reduced.

[0016] In some embodiments, the battery cell further comprises an end cap, an end of the end body away from the main body is provided with an opening, the end cap is provided on the opening, and the pressure relief mechanism is provided on the end cap. With such a design, the introduction of the end cap facilitates the sealing of the shell and provides a closed environment for the electrode assembly.

[0017] In a second aspect, the present application provides a battery device, the battery device comprising any of the above battery cells.

[0018] In a third aspect, the present application provides an electrical device, which includes the above battery device. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 A schematic diagram of the structure of a vehicle provided for some embodiments of the present application.

[0020] Figure 2 An exploded view of a battery device provided in accordance with some embodiments of the present application.

[0021] Figure 3 A schematic diagram of the exploded structure of a battery cell provided in some embodiments of the present application.

[0022] Figure 4 Schematic diagram of the structure of the housing provided in some embodiments of the present application Figure 1 .

[0023] Figure 5 for Figure 4 A structural cross-sectional view of the shell shown in FIG.

[0024] Figure 6 for Figure 4 Another perspective view of the shell structure shown in FIG.

[0025] Figure 7 for Figure 5 The structural cross-sectional view of the shell along the AA direction is shown in FIG.

[0026] Figure 8 Schematic diagram of the structure of the housing provided in some embodiments of the present application Figure 2 .

[0027] Fig. 9 for Figure 8 A structural cross-sectional view of the shell shown in FIG.

[0028] Fig.10 Schematic diagram of the structure of the housing provided in some embodiments of the present application Figure 3 .

[0029] 1000, vehicle; 100, battery device; 200, controller; 300, motor; 10, battery cell; 20, housing; 201, first part; 202, second part; 1, housing; 11, main body; 111, first chamber; 12, end body; 121, second chamber; 13, opening; 2, end cover; 3, electrode assembly; 4, pressure relief mechanism; X, preset direction. DETAILED DESCRIPTION

[0030] In order to make the above-mentioned purposes, features and advantages of the present application more obvious and easy to understand, the specific implementation methods of the present application are described in detail below in conjunction with the accompanying drawings. In the following description, many specific details are set forth to facilitate a full understanding of the present application. However, the present application can be implemented in many other ways different from those described herein, and those skilled in the art can make similar improvements without violating the connotation of the present application, so the present application is not limited by the specific embodiments disclosed below.

[0031] In the description of the present application, it should be understood that if the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise", "axial", "radial", "circumferential", etc. appear, the orientation or position relationship indicated by these terms is based on the orientation or position relationship shown in the accompanying drawings, which is only for the convenience of describing the present application and simplifying the description, and does not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present application.

[0032] In addition, if the terms "first" or "second" appear, these terms are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Therefore, a feature defined as "first" or "second" may explicitly or implicitly include at least one of the features. In the description of this application, if the term "plurality" appears, the meaning of "plurality" is at least two, such as two, three, etc., unless otherwise clearly and specifically defined.

[0033] In this application, unless otherwise clearly specified and limited, if the terms "installed", "connected", "connected", "fixed" and the like appear, these terms should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integrated connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements, unless otherwise clearly defined. For ordinary technicians in this field, the specific meanings of the above terms in this application can be understood according to the specific circumstances.

[0034] In the present application, unless otherwise clearly specified and limited, if there is a description that a first feature is "above" or "below" a second feature, etc., or similar descriptions appear, it may mean that the first and second features are in direct contact, or that the first and second features are in indirect contact through an intermediate medium. Moreover, the first feature being "above", "above" and "above" the second feature may mean that the first feature is directly above or obliquely above the second feature, or simply means that the first feature is higher in level than the second feature. The first feature being "below", "below" and "below" the second feature may mean that the first feature is directly below or obliquely below the second feature, or simply means that the first feature is lower in level than the second feature.

[0035] It should be noted that if an element is referred to as being "fixed to" or "disposed on" another element, it may be directly on the other element or there may be a central element. If an element is considered to be "connected to" another element, it may be directly connected to the other element or there may be a central element at the same time. If any, the terms "vertical", "horizontal", "upper", "lower", "left", "right" and similar expressions used in this application are for illustrative purposes only and do not represent the only implementation method.

[0036] At present, from the perspective of market development, the application of battery devices is becoming more and more extensive. Battery devices are not only used in energy storage power systems such as hydropower, thermal power, wind power and solar power stations, but also widely used in electric vehicles such as electric bicycles, electric motorcycles, electric cars, as well as military equipment and aerospace and other fields. With the continuous expansion of the application field of battery devices, the market demand is also constantly expanding.

[0037] When a battery cell experiences thermal runaway, a large amount of smoke will be generated inside its shell. However, due to the structural design of the shell of a traditional battery cell, some of the smoke generated during thermal runaway cannot effectively reach the end of the shell and release pressure to the outside, causing the shell to easily burst due to increased pressure, thereby reducing the reliability of the battery cell.

[0038] Based on this, in order to solve the problem that the shell of a traditional battery cell is prone to bursting when thermal runaway occurs, the present application provides a battery cell, in which the shell is designed to be a main body and an end body, and a pressure relief mechanism is arranged at the end body, which is conducive to achieving pressure relief of the battery cell in the shell when out of control. At the same time, the cross-sectional area S1 of at least part of the interior of the end body is larger than the cross-sectional area S2 of the interior of the main body, so that more space is reserved in the shell. In this way, when the battery cell experiences thermal runaway, the end of the shell can accommodate more smoke generated during the runaway, reduce the impact of the smoke on the shell, improve the effectiveness of the smoke flowing to the end of the shell, effectively reduce the probability of the battery cell bursting during thermal runaway, achieve normal pressure relief when the battery cell is out of control, and improve the reliability of the battery cell.

[0039] The battery cells disclosed in the embodiments of the present application can be used in, but are not limited to, electrical equipment such as vehicles, ships, or aircraft. A power supply system of the electrical equipment can be composed of the battery cells, battery devices, etc. disclosed in the present application. The embodiments of the present application are described by taking the electrical equipment as a vehicle as an example.

[0040] Please refer to Figure 1 , Figure 1 A schematic diagram of the structure of a vehicle 1000 provided for some embodiments of the present application. The vehicle 1000 may be a fuel vehicle, a gas vehicle or a new energy vehicle, and the new energy vehicle may be a pure electric vehicle, a hybrid vehicle or an extended-range vehicle, etc. A battery device 100 is provided inside the vehicle 1000, and the battery device 100 may be provided at the bottom, head or tail of the vehicle 1000. The battery device 100 may be used to power the vehicle 1000, for example, the battery device 100 may be used as an operating power source for the vehicle 1000. The vehicle 1000 may also include a controller 200 and a motor 300, and the controller 200 is used to control the battery device 100 to power the motor 300, for example, for starting, navigating and driving the vehicle 1000.

[0041] In some embodiments of the present application, the battery device 100 can not only serve as an operating power source for the vehicle 1000, but also serve 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.

[0042] Please refer to Figure 2 , Figure 2An exploded view of a battery device 100 provided in some embodiments of the present application. The battery device 100 includes a box body 20 and a battery cell 10, and the battery cell 10 is contained in the box body 20. Among them, the box body 20 is used to provide a storage space for the battery cell 10, and the box body 20 can adopt a variety of structures. In some embodiments, the box body 20 may include a first part 201 and a second part 202, and the first part 201 and the second part 202 cover each other, and the first part 201 and the second part 202 jointly define a storage space for accommodating the battery cell 10. The second part 202 may be a hollow structure with an opening 13 at one end, and the first part 201 may be a plate-like structure, and the first part 201 covers the open side of the second part 202, so that the first part 201 and the second part 202 jointly define a storage space; the first part 201 and the second part 202 may also be hollow structures with an opening 13 on one side, and the open side of the first part 201 covers the open side of the second part 202. Of course, the box body 20 formed by the first part 201 and the second part 202 can be in various shapes, such as a cylinder, a cuboid, etc.

[0043] In the battery device 100, there may be multiple battery cells 10, and the multiple battery cells 10 may be connected in series, in parallel, or in a mixed connection. A mixed connection means that the multiple battery cells 10 are both connected in series and in parallel. The multiple battery cells 10 may be directly connected in series, in parallel, or in a mixed connection, and then the whole formed by the multiple battery cells 10 is accommodated in the box 20; of course, the battery device 100 may also be a battery module formed by connecting multiple battery cells 10 in series, in parallel, or in a mixed connection, and then the multiple battery modules are connected in series, in parallel, or in a mixed connection to form a whole, and accommodated in the box 20. The battery device 100 may also include other structures, for example, the battery device 100 may also include a busbar component for realizing electrical connection between the multiple battery cells 10.

[0044] Each battery cell 10 may be a secondary battery or a primary battery, or a lithium-sulfur battery, a sodium-ion battery, or a magnesium-ion battery, but is not limited thereto. The battery cell 10 may be cylindrical, flat, rectangular, or in other shapes.

[0045] Please refer to Figure 3 , Figure 3 The schematic diagram of the exploded structure of the battery cell 10 provided in some embodiments of the present application. The battery cell 10 refers to the smallest unit constituting the battery device 100. Figure 3 The battery cell 10 includes an end cover 2, a shell 1, an electrode assembly 3 and other functional components.

[0046] The end cap 2 refers to a component that covers the opening 13 of the shell 1 to isolate the internal environment of the battery cell 10 from the external environment. Without limitation, the shape of the end cap 2 can be adapted to the shape of the shell 1 to match the shell 1. Optionally, the end cap 2 can be made of a material with a certain hardness and strength (such as aluminum alloy), so that the end cap 2 is not easily deformed when squeezed and collided, so that the battery cell 10 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 2. The electrode terminal can be used to electrically connect to the electrode assembly 3 for outputting or inputting electrical energy of the battery cell 10. In some embodiments, the end cap 2 can also be provided with a pressure relief mechanism 4 for releasing the internal pressure when the internal pressure or temperature of the battery cell 10 reaches a threshold. The material of the end cap 2 can also be a variety of materials, such as copper, iron, aluminum, stainless steel, aluminum alloy, plastic, etc., and the embodiments of the present application do not impose special restrictions on this. In some embodiments, an insulating member may be provided inside the end cap 2, and the insulating member may be used to isolate the electrical connection components in the housing 1 from the end cap 2 to reduce the risk of short circuit. For example, the insulating member may be plastic, rubber, or the like.

[0047] The shell 1 is a component used to cooperate with the end cap 2 to form the internal environment of the battery cell 10, wherein the formed internal environment can be used to accommodate the electrode assembly 3, the electrolyte and other components. The shell 1 and the end cap 2 can be independent components, and an opening 13 can be set on the shell 1, and the internal environment of the battery cell 10 is formed by covering the opening 13 with the end cap 2 at the opening 13. Without limitation, the end cap 2 and the shell 1 can also be integrated. Specifically, the end cap 2 and the shell 1 can form a common connection surface before other components are put into the shell, and when the interior of the shell 1 needs to be encapsulated, the end cap 2 covers the shell 1. The shell 1 can be of various shapes and sizes, such as a rectangular parallelepiped, a cylindrical shape, a hexagonal prism, etc. Specifically, the shape of the shell 1 can be determined according to the specific shape and size of the electrode assembly 3. The material of the shell 1 can be various, 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.

[0048] The electrode assembly 3 is a component in the battery cell 10 where electrochemical reactions occur. One or more electrode assemblies 3 may be included in the housing 1. The electrode assembly 3 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 11 of the electrode assembly 3, 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 11 or respectively at both ends of the main body 11. During the charge and discharge process of the battery device 100, the positive active material and the negative active material react with the electrolyte, and the tabs connect the electrode terminals to form a current loop.

[0049] Among them, it should be noted that Figure 3 The shell 1 shown in the figure is only for illustrating the matching relationship between the shell 1 and the electrode assembly 3 and the end cover 2, and the specific structural details of the shell 1 are not shown.

[0050] According to some embodiments of this application, please refer to Figures 3 to 5 The present application provides a battery cell 10, which includes: a shell 1 and an electrode assembly 3. The electrode assembly 3 is accommodated in the shell 1; a pressure relief mechanism 4 is used to relieve pressure in the shell 1; wherein the shell 1 includes a main body 11 and an end body 12 provided at at least one end of the main body 11 along a preset direction X, the pressure relief mechanism 4 is provided at the end body 12, the main body 11 has a first chamber 111 for accommodating the electrode assembly 3, the end body 12 has a second chamber 121 connected to the first chamber 111, and along the direction perpendicular to the preset direction X, the cross-sectional area S1 of at least part of the second chamber 121 is greater than the cross-sectional area S2 of the first chamber 111.

[0051] The main body 11 refers to the structure on the shell 1 that mainly accommodates the electrode assembly 3, and the end body 12 refers to the end structure of the shell 1 along the preset direction X. The end body 12 can be arranged at one end of the main body 11, or at both ends of the main body 11. When the electrode assembly 3 is accommodated in the first chamber 111 of the main body 11, a part of the electrode assembly 3 can extend into the second chamber 121 of the end body 12. The shapes of the main body 11 and the end body 12 can be designed in a variety of ways, for example: the shapes of the main body 11 and the end body 12 can be, but not limited to, square, cylindrical, etc.

[0052] The pressure relief mechanism 4 refers to a structure for releasing the internal pressure when the internal pressure or temperature of the battery cell 10 reaches a threshold value. The pressure relief mechanism 4 is arranged at the end body 12. When the battery cell 10 has thermal runaway, most of the generated smoke will flow from the first chamber 111 of the main body 11 to the second chamber 121 of the end body 12, and finally be discharged outward from the pressure relief mechanism 4 to achieve directional pressure relief.

[0053] The cross-sectional area of ​​at least part of the second chamber 121 in the vertical preset direction X is larger than the cross-sectional area of ​​the first chamber 111, indicating that the shell 1 formed by the main body 11 and the end body 12 is a variable cross-sectional structure. The cross-sectional area of ​​the second chamber 121 is larger than the cross-sectional area of ​​the first chamber 111, so that the lateral space of at least part of the end body 12 is larger than the lateral space of the main body 11, which can mitigate the impact of the smoke generated when out of control and reduce the pressure on the shell 1.

[0054] It should be noted that, along the direction perpendicular to the preset direction X, the cross section S1 of the second chamber 121 refers to a closed interception line formed on the wall of the second chamber 121 by intercepting the second chamber 121 with a plane perpendicular to the preset direction X. The area enclosed by the interception line is the cross section S1 of the second chamber 121. For details, please refer to Figure 6 Similarly, the section S2 of the first chamber 111 refers to a closed interception line formed on the wall of the first chamber 111 by intercepting the first chamber 111 with a plane perpendicular to the preset direction X. The area enclosed by the interception is the section S2 of the first chamber 111. For details, please refer to Figure 7 The area indicated by the middle section line S2.

[0055] With such a design, when the battery cell 10 experiences thermal runaway, the end of the shell 1 can accommodate more smoke generated during the runaway, thereby alleviating the impact of the smoke on the shell 1, effectively reducing the probability of the shell 1 of the battery cell 10 exploding during thermal runaway, and improving the reliability of the battery cell 10.

[0056] According to some embodiments of the present application, optionally, please refer to Figure 8 and Fig. 9 The cross-sectional area S1 of the second chamber 121 of at least one end body portion 12 increases from one end of the second chamber 121 close to the first chamber 111 to one end of the second chamber 121 far from the first chamber 111 .

[0057] The number of the end body 12 can be one or two. When there are two end body 12, the cross-sectional area S1 of the second chamber 121 of one end body 12 can be increased along the preset direction X, and the cross-sectional area S1 of the second chamber 121 of the other end body 12 can remain unchanged along the preset direction X. For details, please refer to Fig.10 Alternatively, the cross-sectional area S1 of the second chamber 121 of the two end body portions 12 may increase along the preset direction X.

[0058] The increasing trend refers to that the cross-sectional area of ​​the second chamber 121 increases in the preset direction X, so that the cross-sectional area of ​​the second chamber 121 at one end away from the first chamber 111 is larger than the cross-sectional area of ​​the second chamber 121 at one end close to the first chamber 111. The increasing trend may include that the cross-sectional area of ​​the second chamber 121 gradually increases in the preset direction X; or gradually increases first and then remains unchanged; or gradually increases first, then remains unchanged, and then gradually increases again, etc.

[0059] For specific embodiments, please refer to Figure 8The end body 12 is respectively disposed at both ends of the main body 11 along the preset direction X, and the cross-sectional area S1 of the second chamber 121 of each end body 12 gradually increases from the end of the second chamber 121 close to the first chamber 111 to the end of the second chamber 121 away from the first chamber 111. At this time, the interior of the end body 12 presents a truncated cone shape or a trumpet shape.

[0060] With such a design, the internal cross section of the end body 12 tends to increase in the preset direction X, thereby providing more space to alleviate the impact of smoke and reducing the possibility of the shell 1 bursting due to excessive pressure.

[0061] According to some embodiments of the present application, optionally, please refer to Figure 5 The cross-sectional area S1 of the second chamber 121 of at least one end body portion 12 remains consistent from one end of the second chamber 121 close to the first chamber 111 to one end of the second chamber 121 away from the first chamber 111 .

[0062] The cross-sectional area S1 of the second chamber 121 remains consistent in the preset direction X, indicating that the interior of the end body 12 is a uniform cross-sectional structure, and its shape can also be designed in a variety of ways, for example: the second chamber 121 can be, but is not limited to, cylindrical, quadrangular, pentagonal, etc. Specifically in some embodiments, the interior of the end body 12 is a cylindrical structure.

[0063] With such a design, the interior of the end body 12 is designed as a uniform cross-sectional structure, so that the cross-section of the interior of the end body 12 is larger than the cross-section of the main body 11 in the preset direction X, which greatly increases the exhaust space at the end of the shell 1 and effectively reduces the probability of the shell 1 bursting due to excessive pressure.

[0064] According to some embodiments of the present application, optionally, please refer to Figure 5 and Fig. 9 The length of the end body 12 along the preset direction X is recorded as L1, and the length of the shell 1 along the preset direction X is recorded as L0, wherein 1 / 12≤L1 / L0<1 / 2.

[0065] The length of the end body 12 is reasonably designed to increase the exhaust space at the end of the housing 1, but if it is too long, the overall size of the battery cell 10 will increase, resulting in an increase in the installation space of the battery cell 10. For this reason, L1 / L0 can be between 1 / 12 and 1 / 2 (excluding 1 / 2), for example, but not limited to 1 / 12, 1 / 10, 1 / 8, 1 / 6, 1 / 4, 1 / 3, etc.

[0066] With such a design, the ratio of the length of the end body 12 to the length of the shell 1 is controlled between 1 / 12 and 1 / 2. On the premise of satisfying the effective space at the end of the shell 1, the overall size of the battery cell 10 is reduced, which is beneficial to improving the installation space utilization of the battery cell 10.

[0067] According to some embodiments of the present application, optionally, L1 / L0 also satisfies the condition: 1 / 10≤L1 / L0≤1 / 5.

[0068] L1 / L0 can take values ​​between 1 / 10 and 1 / 5, for example, but not limited to, 1 / 10, 1 / 9, 1 / 8, 1 / 7, 1 / 6, 1 / 5, etc.

[0069] With such a design, the ratio of the length of the end body 12 to the length of the shell 1 is controlled between 1 / 10 and 1 / 5, further effectively taking into account the space at the end of the shell 1 and the overall size of the battery cell 10 .

[0070] According to some embodiments of the present application, optionally, L0 satisfies the condition: 50 mm ≤ L0 ≤ 300 mm.

[0071] The length L0 of the housing 1 may be between 50 mm and 300 mm, for example, but not limited to, 50 mm, 60 mm, 70 mm, 80 mm, 90 mm, 100 mm, 150 mm, 200 mm, 250 mm, 300 mm, etc. In some embodiments, the length L0 of the housing 1 may also be between 80 mm and 200 mm.

[0072] With such a design, the length of the shell 1 is controlled between 50 mm and 300 mm, and a battery cell 10 of a reasonable length is obtained, so that smoke can effectively reach the end body 12 in the event of a loss of control, thereby reducing the risk of the shell 1 bursting.

[0073] According to some embodiments of the present application, optionally, please refer to Figure 4 and Figure 8 The cross section of the second chamber 121 perpendicular to the preset direction X is constructed as a circular structure, the main body 11 is constructed as a cylindrical structure, and the preset direction X is consistent with the axial direction of the main body 11.

[0074] The cross section of the second chamber 121 is a circular structure, indicating that the interior of the end body 12 can be cylindrical, truncated cone, etc. The main body 11 is a cylindrical structure, indicating that the battery cell 10 is a cylindrical battery. In this case, the electrode assembly 3 can be a winding structure and is installed in the main body 11 along the axial direction of the main body 11.

[0075] Such a design can leave more space for the ends of the cylindrical battery, thereby reducing the risk of the shell 1 exploding when the cylindrical battery is out of control.

[0076] According to some embodiments of the present application, optionally, please refer to Figure 5 and Fig. 9 The maximum diameter of the second chamber 121 is recorded as D1, and the maximum diameter of the first chamber 111 is recorded as D0, wherein D1 / D0≥1.05.

[0077] When the second chamber 121 is a cylindrical structure, the maximum diameter D1 may be the diameter of any point of the second chamber 121 ; when the second chamber 121 is a truncated cone structure, the maximum diameter D1 may be the diameter of one end of the second chamber 121 away from the first chamber 111 .

[0078] The ratio of the maximum diameter D1 of the second chamber 121 to the maximum diameter D0 of the first chamber 111 may be greater than 1.05, for example, 1.05, 1.1, 1.15, 1.2, 1.25, 1.3, 1.35, 1.4, 1.45, 1.5, etc.

[0079] With such a design, the ratio of the maximum diameter of the second chamber 121 to the maximum diameter of the first chamber 111 is controlled to be above 1.05, so that the internal space of the end body 12 is increased, and the risk of the shell 1 bursting when out of control is reduced.

[0080] According to some embodiments of the present application, optionally, D1 / D0 further satisfies the condition: D1 / D0≤1.3.

[0081] The ratio of the maximum diameter D1 of the second chamber 121 to the maximum diameter D0 of the first chamber 111 is limited within 1.3, for example, it can be but not limited to 1.05, 1.1, 1.15, 1.2, 1.25, 1.3.

[0082] With such a design, the ratio of the maximum diameter of the second chamber 121 to the maximum diameter of the first chamber 111 is limited to within 1.3, and the diameter size of the end body 12 is controlled as much as possible while reducing the risk of explosion when the shell 1 is thermally runaway.

[0083] According to some embodiments of the present application, optionally, D0 satisfies the condition: 10 mm ≤ D0 ≤ 80 mm.

[0084] The maximum diameter D0 of the first chamber 111 may be between 10 mm and 80 mm, for example, but not limited to, 10 mm, 20 mm, 30 mm, 40 mm, 50 mm, 60 mm, 70 mm, 80 mm, etc. In some embodiments, the maximum diameter D0 of the first chamber 111 may also be between 30 mm and 60 mm.

[0085] With such a design, the maximum diameter of the first chamber 111 is controlled between 10 mm and 80 mm, thereby obtaining a cylindrical battery cell 10 of appropriate size.

[0086] According to some embodiments of the present application, optionally, please refer to Figure 4 The end body parts 12 include two end body parts 12, which are respectively arranged at two ends of the main body part 11 along the preset direction X.

[0087] The two end bodies 12 are respectively arranged at the two ends of the main body 11 and are respectively connected to the main body 11. The connection between the end body 12 and the main body 11 may be, but not limited to, threaded connection, welding, clamping, etc. Of course, the end body 12 and the main body 11 may also be an integrated structure.

[0088] With such a design, the end bodies 12 are respectively provided at both ends of the main body 11 , so that the internal spaces at both ends of the shell 1 are enlarged, thereby alleviating the impact of smoke on the shell 1 during thermal runaway.

[0089] According to some embodiments of the present application, optionally, the battery cell 10 further includes an end cover 2 , an end of the end body 12 away from the main body 11 is provided with an opening 13 , the end cover 2 is covered with the opening 13 , and the pressure relief mechanism 4 is provided on the end cover 2 .

[0090] The end cap 2 refers to a component that covers the opening 13 of the housing 1 to isolate the internal environment of the battery cell 10 from the external environment. When the housing 1 includes a main body 11 and an end body 12 disposed at one end of the main body 11, the opening 13 may be disposed at an end of the end body 12 away from the main body 11; when the housing 1 includes a main body 11 and end bodies 12 disposed at both ends of the main body 11, the opening 13 is disposed at an end of at least one end body 12 away from the main body 11.

[0091] With such a design, the end cover 2 is introduced to facilitate sealing of the shell 1 and provide a closed environment for the electrode assembly 3 .

[0092] According to some embodiments of the present application, the present application provides a battery device 100 , and the battery device 100 includes any of the above battery cells 10 .

[0093] According to some embodiments of the present application, the present application provides an electric device, and the electric device includes the above battery device 100.

[0094] According to some embodiments of this application, please refer to Figures 4 to 10 The present application provides a battery cell 10, which includes a shell 1, an end cover 2 and an electrode assembly 3. The shell 1 has an opening 13 at one end along a preset direction X, the electrode assembly 3 is accommodated in the shell 1, and the end cover 2 is covered on the opening 13. The shell 1 includes a main body 11 and end bodies 12 provided at both ends of the main body 11 along the preset direction X. The main body 11 is a cylindrical structure, and the end body 12 can be a cylindrical structure; it can also be a truncated cone structure. When the end body 12 is a truncated cone structure, the inner diameter of the end body 12 gradually increases from the end of the end body 12 close to the main body 11 to the end of the end body 12 away from the main body 11.

[0095] The technical features of the above-described embodiments may be arbitrarily combined. To make the description concise, not all possible combinations of the technical features in the above-described embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0096] The above-described embodiments only express several implementation methods of the present application, and the descriptions thereof are relatively specific and detailed, but they cannot be construed as limiting the scope of the patent application. It should be pointed out that, for a person of ordinary skill in the art, several variations and improvements can be made without departing from the concept of the present application, and these all belong to the protection scope of the present application. Therefore, the protection scope of the patent application shall be subject to the attached claims.

Claims

1. A battery cell, characterized in that: The battery cell comprises: Housing (1); An electrode assembly (3) is accommodated in the housing (1); A pressure relief mechanism (4) for relieving pressure in the housing (1); The shell (1) comprises a main body (11) and an end body (12) arranged at at least one end of the main body (11) along a preset direction (X), the pressure relief mechanism (4) is arranged at the end body (12), the main body (11) has a first chamber (111) for accommodating the electrode assembly (3), the end body (12) has a second chamber (121) connected to the first chamber (111), and along a direction perpendicular to the preset direction (X), the cross-sectional area S1 of at least part of the second chamber (121) is greater than the cross-sectional area S2 of the first chamber (111).

2. The battery cell according to claim 1, characterized in that: The cross-sectional area S1 of the second chamber (121) of at least one of the end bodies (12) increases from an end of the second chamber (121) close to the first chamber (111) to an end of the second chamber (121) far from the first chamber (111).

3. The battery cell according to claim 1, characterized in that: The cross-sectional area S1 of the second chamber (121) of at least one of the end bodies (12) remains consistent from one end of the second chamber (121) close to the first chamber (111) to one end of the second chamber (121) far from the first chamber (111).

4. The battery cell according to claim 1, characterized in that: The length of the end body (12) along the preset direction (X) is recorded as L1, and the length of the shell (1) along the preset direction (X) is recorded as L0, wherein 1 / 12≤L1 / L0<1 / 2.

5. The battery cell according to claim 4, characterized in that: L1 / L0 also satisfies the condition: 1 / 10≤L1 / L0≤1 / 5.

6. The battery cell according to claim 4, characterized in that: The conditions that L0 satisfies are: 50mm≤L0≤300mm.

7. The battery cell according to any one of claims 1 to 6, characterized in that: The cross section of the second chamber (121) perpendicular to the preset direction (X) is constructed as a circular structure, the first chamber (111) is constructed as a cylindrical structure, and the preset direction (X) is consistent with the axial direction of the main body (11).

8. The battery cell according to claim 7, characterized in that: The maximum diameter of the second chamber (121) is recorded as D1, and the maximum diameter of the first chamber (111) is recorded as D0, wherein D1 / D0≥1.

05.

9. The battery cell according to claim 8, characterized in that: The condition that D1 / D0 also satisfies is: D1 / D0≤1.

3.

10. The battery cell according to claim 8, characterized in that: The condition that D0 satisfies is: 10mm≤D0≤80mm.

11. The battery cell according to any one of claims 1 to 6, characterized in that: The end body parts (12) include two end body parts (12), and the two end body parts (12) are respectively arranged at two ends of the main body part (11) along the preset direction (X).

12. The battery cell according to any one of claims 1 to 6, characterized in that: The battery cell further comprises an end cover (2); an end of the end body (12) away from the main body (11) is provided with an opening (13); the end cover (2) is arranged to cover the opening (13); and the pressure relief mechanism (4) is arranged on the end cover (2).

13. A battery device, characterized in that: The battery device comprises the battery cell according to any one of claims 1 to 11.

14. An electrical device, characterized in that: The electrical equipment comprises the battery device according to claim 13.

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