Battery cells, batteries and electrical devices

Abstract

The present application discloses a battery cell, a battery and an electrical device. The battery cell includes an electrode assembly and a shell, wherein the electrode assembly is arranged inside the shell, the shell includes a shell and an end cover, the shell is provided with an opening, the end cover is provided at the opening of the shell, the end cover includes a cover body, a reinforcing rib provided on the cover body and a pressure relief mechanism, and the reinforcing rib is provided near the pressure relief mechanism. In the embodiment of the present application, reinforcing ribs are provided at a position of the end cover near the pressure relief mechanism, which can improve the deformation resistance of the end cover, reduce the risk of short circuit between the positive electrode plate and the negative electrode plate of the electrode assembly at the end cover, and thus improve the thermal runaway resistance 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 and an electrical device. Background Art

[0002] In recent years, with the rapid development of new energy technology, new energy vehicles have been used more and more widely, gradually replacing traditional fuel vehicles and becoming one of the mainstream means of transportation. As the power source of new energy vehicles, power batteries are one of the core devices of new energy vehicles. Therefore, the safety performance of power batteries has become the focus of people's attention.

[0003] In the development of battery technology, how to improve the ability of battery cells to resist thermal runaway is a research direction in battery technology. Utility Model Content

[0004] The embodiments of the present application provide a battery cell, a battery, and an electrical device, which can improve the thermal runaway resistance of the battery cell.

[0005] In the first aspect, an embodiment of the present application provides a battery cell, which includes an electrode assembly and a shell, wherein the electrode assembly is arranged inside the shell, the shell includes a shell and an end cover, the shell is provided with an opening, the end cover is covered at the opening of the shell, the end cover includes a cover body, a reinforcing rib arranged on the cover body, and a pressure relief mechanism, wherein the reinforcing rib is arranged close to the pressure relief mechanism.

[0006] In the above scheme, the pressure relief mechanism of the battery cell is generally arranged at a relatively fragile position of the end cover, so that when the internal air pressure of the battery cell is too high, the pressure relief mechanism can be smoothly opened to relieve pressure. In the embodiment of the present application, reinforcing ribs are arranged at a position of the end cover close to the pressure relief mechanism, which can improve the deformation resistance of the end cover. If the battery cell next to the battery cell undergoes thermal runaway and expands and squeezes the battery cell, the end cover of the battery cell is not easily deformed, reducing the risk of short circuit between the positive and negative pole pieces of the electrode assembly at the end cover, thereby improving the thermal runaway resistance of the battery cell.

[0007] In some embodiments, the reinforcing ribs extend to the edge of the shell, further improving the deformation resistance of the battery cell, thereby improving the thermal runaway resistance of the battery cell.

[0008] In some embodiments, the housing includes two first side surfaces that are oppositely disposed along a width direction of the battery cell, and the reinforcing ribs extend to the first side surfaces.

[0009] In the above solution, the first side surfaces of adjacent battery cells are generally close to each other, so the reinforcing ribs in the embodiment of the present application extend to the first side surface, which can further improve the thermal runaway resistance of the battery cell.

[0010] In some embodiments, the reinforcing ribs are disposed on a side of the end cover facing the housing, further improving the deformation resistance of the battery cell, thereby improving the thermal runaway resistance of the battery cell.

[0011] In some embodiments, the number of reinforcing ribs is two, and the two reinforcing ribs are cross-arranged, thereby further improving the deformation resistance of the end cover.

[0012] In some embodiments, in the height direction of the battery cell, the orthographic projection of the reinforcing rib on the end cover at least partially overlaps with the orthographic projection of the pressure relief mechanism on the end cover.

[0013] In the above solution, the reinforcing ribs are arranged at the position where the structural strength of the end cover is weakest, which can further improve the deformation resistance of the end cover.

[0014] In some embodiments, the end cover includes a cover body and an insulating member, the insulating member is arranged on the side of the cover body facing the shell, the pressure relief mechanism is arranged on the cover body, the insulating member protrudes toward the shell at a position corresponding to the pressure relief mechanism to form a raised portion, and the reinforcing ribs are arranged inside the raised portion.

[0015] In the above solution, the raised part facilitates gas to gather inside, and the pressure relief mechanism can be opened smoothly. In the embodiment of the present application, the reinforcing rib is arranged inside the raised part, which saves space inside the shell and does not affect the energy density of the battery cell.

[0016] In some embodiments, the reinforcing rib includes a horizontal portion and a vertical portion connected to each other, the horizontal portion is fixed to the end cover, and the vertical portion is fixed to the shell.

[0017] In the above solution, by connecting the reinforcing ribs to the shell and the end cover respectively, the thermal runaway resistance of the battery cell can be further improved.

[0018] In some embodiments, the vertical portion is connected to the first side surface. Generally, the first side surfaces of adjacent battery cells are close to each other, so the vertical portion of the embodiment of the present application is connected to the first side surface, which can further improve the thermal runaway resistance of the battery cell.

[0019] In some embodiments, the number of reinforcing ribs is two, and the two reinforcing ribs are arranged at intervals along the width direction of the battery cell, further increasing the thermal runaway resistance of the battery cell.

[0020] In some embodiments, the reinforcing ribs are disposed on a side of the end cover facing away from the shell, and do not occupy the space inside the shell, thereby not affecting the energy density of the battery cell.

[0021] In some embodiments, there are two reinforcing ribs, which are respectively disposed on both sides of the pressure relief mechanism, further increasing the thermal runaway resistance of the battery cell.

[0022] In some embodiments, the reinforcing ribs extend along the width direction of the battery cell, further increasing the thermal runaway resistance of the battery cell.

[0023] In a second aspect, an embodiment of the present application further provides a battery comprising a plurality of battery cells according to any of the above embodiments.

[0024] In a third aspect, an embodiment of the present application further provides an electrical device, comprising the above-mentioned battery, wherein the battery is used to provide electrical energy.

[0025] The above description is only an overview of the technical solution of the present application. In order to more clearly understand the technical means of the present application, it can be implemented in accordance with the contents of the specification. In order to make the above and other purposes, features and advantages of the present application more obvious and easy to understand, the specific implementation methods of the present application are listed below. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings required for use in the embodiments of the present application will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0027] Figure 1 A schematic diagram of the structure of a vehicle according to some embodiments of the present application;

[0028] Figure 2 An exploded view of a battery according to some embodiments of the present application;

[0029] Figure 3 A schematic diagram of the structure of a battery module according to some embodiments of the present application;

[0030] Figure 4 A schematic diagram of the exploded structure of a battery cell according to some embodiments of the present application;

[0031] Figure 5 is a partial structural schematic diagram of a battery cell housing provided in some embodiments of the present application;

[0032] Figure 6 is a schematic diagram of the structure of the end cap provided in some embodiments of the present application;

[0033] Figure 7 It is a partial structural schematic diagram of a battery cell housing provided in some other embodiments of the present application;

[0034] Figure 8 It is a schematic diagram of the structure of the end cover provided in some other embodiments of the present application.

[0035] Description of reference numerals:

[0036] Vehicle 1000; battery 100; controller 200; motor 300; upper cover 10; box body 30; battery module 400; 20, battery cell; 22, shell; 221, first side; 222, second side; 21, end cover; 211, cover body; 212, insulating member; 213, raised portion; 26, electrode terminal; 23, electrode assembly; 24, pressure relief mechanism; 25, reinforcing rib; 251, horizontal portion; 252, vertical portion; height direction Y; width direction X. DETAILED DESCRIPTION

[0037] The following detailed description and drawings of the embodiments of the present application are used to illustrate the principles of the present application, but cannot be used to limit the scope of the present application, that is, the present application is not limited to the described embodiments.

[0038] In the description of the present application, it should be noted that, unless otherwise specified, "multiple" means more than two; the terms "upper", "lower", "left", "right", "inside", "outside", etc., indicating the orientation or positional relationship, are only for the convenience of describing the present application and simplifying the description, and do 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. In addition, the terms "first", "second", "third", etc. are only used for descriptive purposes and cannot be understood as indicating or implying relative importance. "Vertical" is not strictly vertical, but is within the allowable error range. "Parallel" is not strictly parallel, but is within the allowable error range.

[0039] Reference to "embodiments" in this application means that a particular feature, structure, or characteristic described in conjunction with the embodiments may be included in at least one embodiment of the present application. The appearance of the phrase in various locations in the specification does not necessarily refer to the same embodiment, nor is it an independent or alternative embodiment that is mutually exclusive with other embodiments. It is explicitly and implicitly understood by those skilled in the art that the embodiments described in this application may be combined with other embodiments.

[0040] The directional words appearing in the following description are all directions shown in the figures, and do not limit the specific structure of this application. In the description of this application, it should also be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection; it can be directly connected or indirectly connected through an intermediate medium. For ordinary technicians in this field, the specific meanings of the above terms in this application can be understood according to the specific circumstances.

[0041] In the present application, battery cells may include lithium-ion secondary battery cells, lithium-ion primary battery cells, lithium-sulfur battery cells, sodium-lithium-ion battery cells, sodium-ion battery cells or magnesium-ion battery cells, etc., and the embodiments of the present application do not limit this. Battery cells may be cylindrical, flat, rectangular or other shapes, etc., and the embodiments of the present application do not limit this. Battery cells are generally divided into three types according to the packaging method: cylindrical battery cells, square battery cells and soft-pack battery cells, and the embodiments of the present application do not limit this.

[0042] The battery mentioned in the embodiments of the present application refers to a single physical module including one or more battery cells to provide higher voltage and capacity. For example, the battery mentioned in the present application may include a battery module or a battery pack. The battery generally includes a box for encapsulating one or more battery cells. The box can prevent liquid or other foreign matter from affecting the charging or discharging of the battery cells.

[0043] The battery cell includes an electrode assembly and an electrolyte. The electrode assembly is composed of a positive electrode sheet, a negative electrode sheet and a separator. The battery cell mainly relies on the movement of metal ions between the positive electrode sheet and the negative electrode sheet to work. The positive electrode sheet includes a positive electrode current collector and a positive electrode active material layer. The positive electrode active material layer is coated on the surface of the positive electrode current collector. The current collector not coated with the positive electrode active material layer protrudes from the current collector coated with the positive electrode active material layer. The current collector not coated with the positive electrode active material layer is stacked as a positive electrode tab. Taking lithium-ion batteries as an example, the material of the positive electrode current collector can be aluminum, and the positive electrode active material can be lithium cobalt oxide, lithium iron phosphate, ternary lithium or lithium manganese oxide. The negative electrode sheet includes a negative electrode current collector and a negative electrode active material layer. The negative electrode active material layer is coated on the surface of the negative electrode current collector. The current collector not coated with the negative electrode active material layer protrudes from the current collector coated with the negative electrode active material layer. The current collector not coated with the negative electrode active material layer is stacked as a negative electrode tab. The material of the negative electrode current collector can be copper, and the negative electrode active material can be carbon or silicon. The material of the isolation film may be PP (polypropylene) or PE (polyethylene), etc. In addition, the electrode assembly may be a winding structure or a stacked structure, but the embodiments of the present application are not limited thereto.

[0044] The battery cells disclosed in the embodiments of the present application can be used in, but not limited to, electrical devices such as vehicles, ships or aircraft. A power supply system comprising the battery cells and batteries disclosed in the present application can be used to form the electrical device, which is beneficial to improving the stability of battery performance and battery life.

[0045] The embodiment of the present application provides an electric device using a battery as a power source, and the electric device may be, but is not limited to, a mobile phone, a tablet, a laptop, an electric toy, an electric tool, a battery car, an electric car, a ship, a spacecraft, etc. Among them, the electric toy may include a fixed or mobile electric toy, such as a game console, an electric car toy, an electric ship toy, and an electric airplane toy, etc., and the spacecraft may include an airplane, a rocket, a space shuttle, and a spacecraft, etc.

[0046] For the convenience of description, the following embodiments are described by taking a vehicle 1000 as an example of an electrical device according to an embodiment of the present application.

[0047] Please refer to Figure 1 , Figure 1 A schematic diagram of the structure of a vehicle provided for some embodiments of the present application. 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 100 is provided inside the vehicle 1000, and the battery 100 may be provided at the bottom, head or tail of the vehicle 1000. The battery 100 may be used to power the vehicle 1000, for example, the battery 100 may 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 100 to power the motor 300, for example, for starting, navigating and driving the vehicle 1000.

[0048] In some embodiments of the present application, the battery 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.

[0049] Please refer to Figure 2 , Figure 2 An exploded diagram of a battery provided for some embodiments of the present application. The battery 100 includes a battery case and a battery cell 20. In some embodiments, the battery case may include an upper cover 10 and a case 30, the upper cover 10 and the case 30 cover each other, and the upper cover 10 and the case 30 jointly define a receiving cavity for accommodating the battery cell 20. The case 30 may be a hollow structure with one end open, the upper cover 10 may be a plate-like structure, the upper cover 10 covers the open side of the case 30, so that the upper cover 10 and the case 30 jointly define a receiving cavity; the upper cover 10 and the case 30 may also be hollow structures with one side open, and the open side of the upper cover 10 covers the open side of the case 30. Of course, the battery case formed by the upper cover 10 and the case 30 may be in a variety of shapes, such as a cylinder, a cuboid, etc.

[0050] Figure 3This is a schematic diagram of the structure of the battery module of some embodiments of the present application. In the battery 100, there can be multiple battery cells 20, and the multiple battery cells 20 can be connected in series, in parallel, or in mixed connection. Mixed connection means that the multiple battery cells 20 are both connected in series and in parallel. The multiple battery cells 20 can be directly connected in series, in parallel, or in mixed connection, and then the whole formed by the multiple battery cells 20 is accommodated in the box; of course, the battery 100 can also be a battery module formed by connecting multiple battery cells 20 in series, in parallel, or in mixed connection, and the multiple battery modules are then connected in series, in parallel, or in mixed connection to form a whole, and accommodated in the box. The battery 100 may also include other structures. For example, the battery 100 may also include a busbar component for realizing electrical connection between the multiple battery cells 20.

[0051] Each battery cell 20 may be a secondary battery cell or a primary battery cell, or a lithium-sulfur battery cell, a sodium-ion battery cell, or a magnesium-ion battery cell, but is not limited thereto. The battery cell 20 may be cylindrical, flat, rectangular, or in other shapes.

[0052] Please refer to Figure 4 , Figure 4 Schematic diagram of the exploded structure of a battery cell provided in some embodiments of the present application. A battery cell 20 refers to the smallest unit constituting a battery. The battery cell 20 includes an end cap 21, a housing 22, an electrode assembly 23 and other functional components.

[0053] The end cap 21 refers to a component that covers the opening of the shell 22 to isolate the internal environment of the battery cell 20 from the external environment. Without limitation, the shape of the end cap 21 can be adapted to the shape of the shell 22 to match the shell 22. Optionally, the end cap 21 can be made of a material with a certain hardness and strength (such as aluminum alloy), so that the end cap 21 is not easily deformed when squeezed and collided, so that the battery cell 20 can have a higher structural strength and the safety performance can also be improved. Functional components such as electrode terminals 26 can be provided on the end cap 21. The electrode terminal 26 can be used to electrically connect to the electrode assembly 23 for outputting or inputting electrical energy of the battery cell 20. In some embodiments, the end cap 21 can also be provided with a pressure relief mechanism for releasing the internal pressure when the internal pressure or temperature of the battery cell 20 reaches a threshold. The material of the end cap 21 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 21, and the insulating member may be used to isolate the electrical connection components in the housing 22 from the end cap 21 to reduce the risk of short circuit. For example, the insulating member may be plastic, rubber, or the like.

[0054] The shell 22 is a component used to cooperate with the end cap 21 to form the internal environment of the battery cell 20. The formed internal environment can be used to accommodate the electrode assembly 23, the electrolyte and other components. The shell 22 and the end cap 21 can be independent components. An opening can be set on the shell 22, and the internal environment of the battery cell 20 is formed by covering the opening with the end cap 21 at the opening. In some examples, the shell 22 is a hollow structure with an opening on one side, and the end cap 21 is one and covers the opening of the shell 22. In other examples, the shell 22 is a hollow structure with openings on both sides, and there are two end caps 21, and the two end caps 21 cover the two openings of the shell 22 respectively. Without limitation, the end cap 21 and the shell 22 can also be integrated. Specifically, the end cap 21 and the shell 22 can form a common connection surface before other components are put into the shell, and when it is necessary to encapsulate the interior of the shell 22, the end cap 21 covers the shell 22. The shell 22 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 22 can be determined according to the specific shape and size of the electrode assembly 23. The shell 22 can be made of various materials, such as copper, iron, aluminum, stainless steel, aluminum alloy, plastic, etc., and the embodiment of the present application does not impose any special restrictions on this.

[0055] The electrode assembly 23 is a component in the battery cell 20 where electrochemical reactions occur. One or more electrode assemblies 23 may be included in the housing 22. The electrode assembly 23 is mainly formed by winding or stacking positive and negative electrode sheets, and a separator is usually provided between the positive and negative electrode sheets. The parts of the positive and negative electrode sheets with active materials constitute the main body of the electrode assembly 23, and the parts of the positive and negative electrode sheets without active materials each constitute a tab. The positive tab and the negative tab may be located together at one end of the main body or at both ends of the main body, respectively. During the charge and discharge process of the battery, the positive active material and the negative active material react with the electrolyte, and the tabs connect the electrode terminals 26 to form a current loop.

[0056] When a normal battery cell in a battery is in thermal runaway, the temperature and pressure inside the thermal runaway battery cell increase due to the rapid generation of heat, and the outer shell of the battery cell is prone to expansion and deformation. The deformed battery cell is prone to squeeze the normal battery cell. Since the electrode assembly is generally thinned at one end near the end cap, after the normal battery cell is squeezed, the positive and negative pole pieces in the thinned area of ​​the electrode assembly near the end cap are prone to overlap and short-circuit, thereby causing thermal runaway of the battery cell.

[0057] In order to solve the above technical problems, an embodiment of the present application provides a battery cell, which includes an electrode assembly and a shell, the electrode assembly is arranged inside the shell, the shell includes a shell and an end cover, the shell is provided with an opening, the end cover is covered at the opening of the shell, the end cover includes a cover body and a reinforcing rib and a pressure relief mechanism arranged on the cover body, and the reinforcing rib is arranged close to the pressure relief mechanism.

[0058] In the above scheme, the pressure relief mechanism of the battery cell is generally arranged at a relatively fragile position of the end cover, so that when the internal air pressure of the battery cell is too high, the pressure relief mechanism can be smoothly opened to relieve pressure. In the embodiment of the present application, reinforcing ribs are arranged at a position of the end cover close to the pressure relief mechanism, which can improve the deformation resistance of the end cover. If the battery cell next to the battery cell undergoes thermal runaway and expands and squeezes the battery cell, the end cover of the battery cell is not easily deformed, thereby reducing the risk of short circuit between the positive and negative pole pieces of the electrode assembly at the end cover, thereby improving the thermal runaway resistance of the battery cell.

[0059] Figure 4 A schematic diagram of the exploded structure of a battery cell according to some embodiments of the present application; Figure 5 It is a partial structural schematic diagram of a battery cell housing provided in some embodiments of the present application.

[0060] Please refer to Figure 4 and Figure 5 In the first aspect, the embodiment of the present application provides a battery cell 20, which includes an electrode assembly 23 and a shell. The electrode assembly 23 is arranged inside the shell. The shell includes a shell 22 and an end cover 21. The shell 22 is provided with an opening. The end cover 21 is covered at the opening of the shell 22. The end cover 21 includes a cover body 211 and a reinforcing rib 25 and a pressure relief mechanism 24 arranged on the cover body 211. The reinforcing rib 25 is arranged close to the pressure relief mechanism 24.

[0061] The pressure relief mechanism 24 is generally composed of one or more pressure relief valves, and can adopt a variety of designs, such as spring-loaded valves, fuses, or pressure relief channels. When an abnormal situation occurs in the battery, such as overcharging, over-discharging, internal short circuit, or overheating, the internal pressure of the battery cell 20 may increase. The function of the pressure relief mechanism 24 is to release the pressure when the pressure reaches the safety limit to prevent the battery from exploding or leaking. Prevent the battery cell 20 from expanding. In some cases, gas may be generated inside the battery cell 20, causing the battery to expand. The pressure relief mechanism 24 can release these gases to prevent the battery cell 20 from being damaged due to expansion.

[0062] The reinforcing rib 25 may be arranged on the side of the end cover 21 facing the housing 22, or on the side of the end cover 21 facing away from the housing 22. The number of the reinforcing rib 25 may be one or more. The reinforcing rib 25 is arranged close to the pressure relief mechanism 24, and may overlap with the pressure relief mechanism 24 and be located below the pressure relief mechanism 24; or the reinforcing rib 25 may not overlap with the pressure relief mechanism 24 and be located beside the pressure relief mechanism 24. The reinforcing rib 25 may be in a strip shape or an L shape.

[0063] In the above scheme, the pressure relief mechanism 24 of the battery cell 20 is generally arranged at a relatively fragile position of the end cover 21, so that when the internal air pressure of the battery cell 20 is too high, the pressure relief mechanism 24 can be smoothly opened to relieve pressure. In the embodiment of the present application, reinforcing ribs 25 are arranged at a position of the end cover 21 close to the pressure relief mechanism 24, which can improve the deformation resistance of the end cover 21. If the battery cell 20 next to the battery cell 20 undergoes thermal runaway and expands and squeezes the battery cell 20, the end cover 21 of the battery cell 20 is not easy to deform, thereby reducing the risk of short circuit between the positive electrode plate and the negative electrode plate in the thinned area of ​​the electrode assembly 23 at the end cover 21, thereby improving the thermal runaway resistance of the battery cell 20.

[0064] In some embodiments, the reinforcing ribs 25 extend to the edge of the housing 22 .

[0065] The reinforcing rib 25 may be connected to the shell 22 , or the reinforcing rib 25 may not be connected to the shell 22 and only contact the edge of the shell 22 .

[0066] The embodiment of the present application further improves the deformation resistance of the battery cell 20 , thereby improving the thermal runaway resistance of the battery cell 20 .

[0067] In some embodiments, the housing 22 includes two first side surfaces 221 that are oppositely disposed along the width direction X of the battery cell 20 , and the reinforcing ribs 25 extend to the first side surfaces 221 .

[0068] The housing 22 may be in the shape of a cuboid, including two first side surfaces 221 and two second side surfaces 222. The two second side surfaces 222 are disposed opposite to each other along the length direction of the battery cell 20, and the first side surface 221 is connected to the second side surface 222. The area of ​​the first side surface 221 is greater than that of the second side surface 222.

[0069] The multiple battery cells 20 of the battery module are arranged in sequence along the width direction X of the battery cells 20, and the first side surfaces 221 of adjacent battery cells 20 are close to each other. Therefore, the reinforcing ribs 25 of the embodiment of the present application extend to the first side surface 221, which can further improve the thermal runaway resistance of the battery cells 20.

[0070] In some embodiments, the reinforcing rib 25 is disposed on a side of the end cover 21 facing the housing 22 , further improving the deformation resistance of the battery cell 20 , thereby improving the thermal runaway resistance of the battery cell 20 .

[0071] In some embodiments, the number of the reinforcing ribs 25 is two, and the two reinforcing ribs 25 are arranged crosswise. The two reinforcing ribs 25 form an X-shape, which further improves the anti-deformation capability of the end cover 21.

[0072] In some embodiments, in the height direction Y along the battery cell 20 , the orthographic projection of the reinforcing rib 25 on the end cover 21 at least partially overlaps with the orthographic projection of the pressure relief mechanism 24 on the end cover 21 .

[0073] The reinforcing rib 25 can be disposed below the pressure relief mechanism 24 without affecting the operation of the pressure relief mechanism 24 .

[0074] In the above solution, the reinforcing rib 25 is arranged at the position where the structural strength of the end cover 21 is weakest, which can further improve the deformation resistance of the end cover 21.

[0075] Figure 6 It is a schematic diagram of the structure of the end cover provided in some embodiments of the present application.

[0076] like Figure 6 As shown, in some embodiments, the end cover 21 includes a cover body 211 and an insulating member 212, the insulating member 212 is arranged on the side of the cover body 211 facing the shell 22, the pressure relief mechanism 24 is arranged on the cover body 211, the insulating member 212 protrudes toward the direction of the shell 22 at a position corresponding to the pressure relief mechanism 24 to form a protrusion 213, and the reinforcing rib 25 is arranged inside the protrusion 213.

[0077] The cover body 211 is generally a metal part, and the insulating part 212 is located between the cover body 211 and the electrode assembly 23 to play an isolation role, preventing the cover body 211 from directly contacting the electrode assembly 23, preventing short circuits, and ensuring the normal operation and safety of the battery.

[0078] The interior of the raised portion 213 is a hollow structure, and the raised portion 213 is provided with a through hole for gas to flow through. When the battery cell 20 experiences thermal runaway and the gas pressure inside the housing 22 is too high, the gas will gather inside the raised portion 213, thereby exerting a large impact force on the pressure relief mechanism 24, causing the pressure relief mechanism 24 to open and release pressure.

[0079] In the above solution, the ridge 213 facilitates gas accumulation therein, and the pressure relief mechanism 24 can be opened smoothly. In the embodiment of the present application, the reinforcing rib 25 is arranged inside the ridge 213, which saves space inside the housing 22 and does not affect the energy density of the battery cell 20.

[0080] Figure 7Schematic diagram of the partial structure of the battery cell housing provided by other embodiments of the present application. Figure 7 As shown, in other embodiments, the reinforcing rib 25 includes a horizontal portion 251 and a vertical portion 252 that are connected to each other, the horizontal portion 251 is fixed to the end cover 21 , and the vertical portion 252 is fixed to the shell 22 .

[0081] The reinforcing rib 25 is in an L-shape, and the horizontal portion 251 or the vertical portion 252 of the reinforcing rib 25 may be in a strip shape or a plate shape to increase the contact area with the end cover 21 and the shell 22 .

[0082] In the above solution, by connecting the reinforcing ribs 25 to the housing 22 and the end cover 21 respectively, the thermal runaway resistance of the battery cell 20 can be further improved.

[0083] In some embodiments, the vertical portion 252 is connected to the first side surface 221. Generally, the first side surfaces 221 of adjacent battery cells 20 are close to each other, so the vertical portion 252 of the embodiment of the present application is connected to the first side surface 221, which can further improve the thermal runaway resistance of the battery cell 20.

[0084] In some embodiments, the number of the reinforcing ribs 25 is two, and the two reinforcing ribs 25 are arranged at intervals along the width direction X of the battery cell 20 , further increasing the thermal runaway resistance of the battery cell 20 .

[0085] Figure 8 It is a schematic diagram of the structure of the end cover provided in some other embodiments of the present application.

[0086] like Figure 8 As shown, in some other embodiments, the reinforcing rib 25 is disposed on a side of the end cover 21 away from the shell 22 , and does not occupy the space inside the shell 22 , thereby not affecting the energy density of the battery cell 20 .

[0087] In some embodiments, the number of the reinforcing ribs 25 is two, and the two reinforcing ribs 25 are respectively disposed on both sides of the pressure relief mechanism 24 , further increasing the thermal runaway resistance of the battery cell 20 .

[0088] In some embodiments, the reinforcing ribs 25 extend along the width direction X of the battery cell 20 , further increasing the thermal runaway resistance of the battery cell 20 .

[0089] In a second aspect, an embodiment of the present application further provides a battery, comprising a plurality of battery cells 20 according to any of the above-mentioned embodiments.

[0090] In a third aspect, an embodiment of the present application further provides an electrical device, comprising the above-mentioned battery, wherein the battery is used to provide electrical energy.

[0091] According to some embodiments of the present application, the present application provides a battery cell 20, the battery cell 20 includes an electrode assembly 23 and a shell, the electrode assembly 23 is arranged inside the shell, the shell includes a shell 22 and an end cover 21, the shell 22 is provided with an opening, the end cover 21 is covered at the opening of the shell 22, the end cover 21 includes a cover body 211 and a reinforcing rib 25 and a pressure relief mechanism 24 provided on the cover body 211, and the reinforcing rib 25 is provided near the pressure relief mechanism 24. The shell 22 includes two first side surfaces 221 arranged opposite to each other along the width direction X of the battery cell 20, and the reinforcing rib 25 extends to the first side surface 221.

[0092] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present application, rather than to limit them; although the present application has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or replace some or all of the technical features therein by equivalents; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the scope of the technical solutions of the embodiments of the present application, and they should all be included in the scope of the claims and specification of the present application. In particular, as long as there is no structural conflict, the various technical features mentioned in the various embodiments can be combined in any way. The present application is not limited to the specific embodiments disclosed herein, but includes all technical solutions that fall within the scope of the claims.

Claims

1. A battery cell, characterized in that: include: Electrode assembly; The outer shell, the electrode assembly is arranged inside the outer shell, the outer shell includes a shell and an end cover, the shell is provided with an opening, the end cover is covered at the opening of the shell, the end cover includes a cover body and a reinforcing rib and a pressure relief mechanism arranged on the cover body, and the reinforcing rib is arranged close to the pressure relief mechanism.

2. The battery cell according to claim 1, characterized in that: The reinforcing ribs extend to the edge of the shell.

3. The battery cell according to claim 2, characterized in that: The housing includes two first side surfaces that are oppositely arranged along a width direction of the battery cell, and the reinforcing ribs extend to the first side surfaces.

4. The battery cell according to claim 3, characterized in that: The reinforcing rib is arranged on a side of the end cover facing the shell.

5. The battery cell according to claim 4, characterized in that: The number of the reinforcing ribs is two, and the two reinforcing ribs are arranged crosswise.

6. The battery cell according to claim 4, characterized in that: In the height direction of the battery cell, an orthographic projection of the reinforcing rib on the end cover at least partially overlaps with an orthographic projection of the pressure relief mechanism on the end cover.

7. The battery cell according to claim 6, characterized in that: The end cover includes a cover body and an insulating member, wherein the insulating member is arranged on a side of the cover body facing the shell, the pressure relief mechanism is arranged on the cover body, the insulating member protrudes toward the shell at a position corresponding to the pressure relief mechanism to form a raised portion, and the reinforcing rib is arranged inside the raised portion.

8. The battery cell according to claim 4, characterized in that: The reinforcing rib includes a horizontal portion and a vertical portion connected to each other, the horizontal portion is fixed to the end cover, and the vertical portion is fixed to the shell.

9. The battery cell according to claim 8, characterized in that: The vertical portion is connected to the first side surface.

10. The battery cell according to claim 9, characterized in that: The number of the reinforcing ribs is two, and the two reinforcing ribs are arranged at intervals along the width direction of the battery cell.

11. The battery cell according to claim 1, characterized in that: The reinforcing rib is arranged on a side of the end cover away from the shell.

12. The battery cell according to claim 11, characterized in that: The number of the reinforcing ribs is two, and the two reinforcing ribs are respectively arranged on both sides of the pressure relief mechanism.

13. The battery cell according to claim 11, characterized in that: The reinforcing ribs extend along a width direction of the battery cell.

14. A battery, characterized in that: The invention comprises a plurality of battery cells according to any one of claims 1 to 13.

15. An electrical device, characterized in that: A battery according to claim 14, for providing electrical energy.

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