Battery cell and manufacturing method and system thereof, battery and electric device

Abstract

The embodiment of the present application provides a battery cell and its manufacturing method and manufacturing system, battery and electrical device. The battery cell of this embodiment includes an electrode assembly, a shell, a pressure relief mechanism and a cover assembly. The shell is provided with a storage space for accommodating the electrode assembly; the shell includes a first side plate located on one side along a first direction; the pressure relief mechanism is arranged on the first side plate; the cover assembly is used to seal the shell; the inner surface of the first side plate of the shell is provided with a first flow channel extending along the inner surface, and the first flow channel is used to guide the gas in the storage space to the pressure relief mechanism, so that the pressure relief mechanism is actuated and releases the pressure when the pressure reaches a threshold. The present application can improve the exhaust rate when the battery cell is in thermal runaway, and improve the safety of the battery cell.

Description

Technical Field

[0001] Embodiments of the present application relate to the field of batteries, and more specifically, to a battery cell and a manufacturing method and system thereof, a battery, and an electrical device. Background Art

[0002] Battery cells are widely used in electronic devices, such as mobile phones, laptop computers, electric vehicles, electric cars, electric airplanes, electric ships, electric toy cars, electric toy ships, electric toy airplanes, and electric tools, etc. Battery cells can include nickel-cadmium battery cells, nickel-hydrogen battery cells, lithium-ion battery cells, and secondary alkaline zinc-manganese battery cells, etc.

[0003] In the development of battery technology, in addition to improving the performance of battery cells, safety is also an issue that cannot be ignored. If the safety of battery cells cannot be guaranteed, the battery cells cannot be used. Therefore, how to enhance the safety of battery cells is a technical problem that needs to be solved urgently in battery technology. Summary of the invention

[0004] The embodiments of the present application provide a battery cell and a manufacturing method and system thereof, a battery, and an electrical device, which can enhance the safety of the battery cell.

[0005] According to the first aspect of the present application, the embodiment of the present application provides a battery cell, including an electrode assembly, a shell, a pressure relief mechanism and a cover assembly. The shell is provided with a storage space for accommodating the electrode assembly; the shell includes a first side plate located on one side along a first direction; the pressure relief mechanism is arranged on the first side plate; the cover assembly is used to seal the shell; the inner surface of the first side plate of the shell is provided with a first flow channel extending along the inner surface, and the first flow channel is used to guide the gas in the storage space to the pressure relief mechanism, so that the pressure relief mechanism is actuated and releases the pressure when the pressure reaches a threshold.

[0006] In the above scheme, the embodiment of the present application sets a first flow channel on the first side plate of the shell, which can guide the gas released by the battery cell during thermal runaway from the accommodation space to the pressure relief mechanism, so that the pressure relief mechanism can be actuated and release the gas in time, thereby improving the exhaust rate of the battery cell during thermal runaway and improving the safety of the battery cell.

[0007] In some embodiments, the first flow channel includes a plurality of first grooves disposed on and extending along the inner surface of the first side plate, and one end of each first groove is connected to the pressure relief mechanism. The first flow channel is provided as a plurality of first grooves, each of which is connected to the pressure relief mechanism. When thermal runaway occurs in the battery cell, the released gas can be guided from the accommodation space to the pressure relief mechanism along the first groove for discharge, thereby increasing the exhaust rate when the battery cell is in thermal runaway and improving the safety of the battery cell. At the same time, the first groove is provided on the inner surface of the first side plate, and will not occupy the accommodation space and affect the energy density of the battery cell.

[0008] In some embodiments, the plurality of first grooves are parallel to each other, which is beneficial to improve the exhaust efficiency along the length direction of the first grooves. Alternatively, the plurality of first grooves extend in a divergent shape around the pressure relief mechanism, which is beneficial to improve the exhaust efficiency in the circumferential direction of the pressure relief mechanism.

[0009] In some embodiments, a protrusion is formed on the inner surface of the first side plate and protrudes toward the accommodation space. The protrusion has a top surface away from the inner surface, and the first flow channel is formed in the space between the top surface and the inner surface of the protrusion. In this embodiment, the top surface of the protrusion is used to support the electrode assembly, and the first flow channel is formed in the space between the top surface and the inner surface of the protrusion, which can increase the exhaust rate when the battery cell is in thermal runaway, thereby improving the safety of the battery cell.

[0010] In some embodiments, the first flow channel includes a plurality of flow channels connected to the pressure relief mechanism; there are a plurality of protrusions, the plurality of protrusions extend in a divergent manner around the pressure relief mechanism as the center and are spaced apart from each other, and a flow channel is formed between two adjacent protrusions and the inner surface. The plurality of protrusions extend in a divergent manner around the pressure relief mechanism as the center and are spaced apart from each other, which is conducive to improving the exhaust efficiency in the circumferential direction of the pressure relief mechanism.

[0011] In some embodiments, the first flow channel includes a plurality of branch flow channels and a connecting flow channel; there are a plurality of protrusions, each of which extends substantially along the second direction of the first side plate; a plurality of protrusions are arranged and spaced apart from each other along the third direction of the first side plate; a branch flow channel is formed between two adjacent protrusions and the inner surface, and two adjacent branch flow channels are connected through the connecting flow channel; at least one of the branch flow channels is connected to the pressure relief mechanism through the connecting flow channel; the second direction is perpendicular to the first direction; and the third direction is perpendicular to the first direction and the second direction. By providing a protrusion extending along the second direction of the first side plate, a branch flow channel is formed between two adjacent protrusions and the inner surface, and the branch flow channel is connected to the pressure relief mechanism through the connecting flow channel, the exhaust efficiency in the second direction can be improved.

[0012] In some embodiments, the housing includes a pair of second side plates arranged opposite to each other along the second direction; a third gap is provided between one end of each protrusion in the second direction and an adjacent second side plate, and the third gap forms at least a portion of the connecting flow channel. By providing the third gap to form a portion of the connecting flow channel that connects the shunt flow channel to the pressure relief mechanism, the gas in the shunt flow channel can be quickly guided to the pressure relief mechanism through the connecting flow channel for discharge.

[0013] In some implementations, at least one protrusion includes a plurality of sub-protrusions, the sub-protrusions are spaced apart along the second direction, a fourth gap is formed between adjacent sub-protrusions, and the fourth gap forms at least a portion of the connecting flow channel. By providing the fourth gap to form a portion of the connecting flow channel that connects the shunt flow channel to the pressure relief mechanism, the gas in the shunt flow channel can be quickly guided to the pressure relief mechanism through the connecting flow channel for discharge.

[0014] In some implementations, the protrusion is configured as an arc or a folded line protruding away from the pressure relief mechanism in the third direction. The arc or folded line protruding away from the pressure relief mechanism can guide the airflow toward the pressure relief mechanism during exhaust, which is conducive to rapid exhaust of gas.

[0015] In some embodiments, an insulating layer is provided on the top surface of the raised portion, and the insulating layer is used to achieve insulation between the electrode assembly and the shell, without the need for additional supporting components, thereby reducing space occupancy and helping to improve the energy density of the battery cell without affecting the exhaust of the battery cell.

[0016] In some embodiments, the housing includes a pair of second side plates arranged opposite to each other in a second direction, and the accommodation space includes a first gap arranged between the electrode assembly and each second side plate; the second direction is perpendicular to the first direction; the housing also includes a pair of third side plates arranged opposite to each other in a third direction, and the accommodation space also includes a second gap arranged between the electrode assembly and each third side plate; the third direction is perpendicular to the first direction and the second direction; the first flow channel is connected to the first gap and / or the second gap. The first flow channel is connected to the accommodation space by being connected to the first gap and / or the second gap.

[0017] In some embodiments, starting from the position where the first flow channel connects to the pressure relief mechanism, the depth of at least part of the first flow channel gradually decreases in the direction away from the pressure relief mechanism. As a result, the depth of at least part of the length of the first flow channel gradually increases in the direction approaching the pressure relief mechanism, forming a slope inclined toward the exhaust direction of the pressure relief mechanism, which is more conducive to guiding the gas to the pressure relief mechanism for discharge and improving the exhaust efficiency.

[0018] In some embodiments, a support member is further included, which is disposed between the first side plate and the electrode assembly to support the electrode assembly; a second flow channel is disposed on the support member, and the second flow channel connects the first flow channel and the accommodation space. The second flow channel is formed on the support member to connect the first flow channel and the accommodation space, which can increase the flow channel area of ​​the exhaust and improve the exhaust efficiency.

[0019] In some embodiments, the second flow channel includes a first through hole penetrating the support member along the first direction, and the first through hole communicates with the first flow channel and the accommodating space.

[0020] In some embodiments, the housing includes a pair of second side plates arranged opposite to each other along a second direction, and the accommodation space includes a first gap arranged between the electrode assembly and each second side plate; the second direction is perpendicular to the first direction; the housing also includes a pair of third side plates arranged opposite to each other along a third direction, and the accommodation space also includes a second gap arranged between the electrode assembly and each third side plate; the third direction is perpendicular to the first direction and the second direction; the support member has a first surface and a second surface arranged opposite to each other, the first surface faces the first side plate, and the second surface faces the electrode assembly; the second flow channel includes a second groove arranged on the first surface, the second groove is connected to the first gap and / or the second gap, and the second groove is connected to the first flow channel. By setting a second groove connected to the first gap and / or the second gap and the first flow channel on the support member, the flow channel area of ​​the exhaust gas can be increased, and the exhaust efficiency can be improved.

[0021] In some embodiments, an insulating film is further included, which is used to wrap a part of the electrode assembly and separate the electrode assembly from the shell; the insulating film includes a first side film located between the electrode assembly and the support member; the first side film has a second through hole, and the second through hole and the first through hole of the support member do not overlap in projection in the first direction. The second through hole on the first side film of the insulating film and the first through hole on the support member do not overlap in projection in the first direction, and while achieving reliable insulation between the electrode assembly and the first side plate, the first through hole and the second through hole can be used to connect the accommodation space with the first flow channel, thereby improving the exhaust efficiency.

[0022] According to a second aspect of the present application, a battery is provided, comprising the battery cell of the first aspect.

[0023] According to a third aspect of the present application, there is provided an electrical device, comprising: the battery of the second aspect.

[0024] In some embodiments, the electrical device is a vehicle, a watercraft, or a spacecraft.

[0025] According to a fourth aspect of the present application, a method for manufacturing a battery cell is provided, comprising providing an electrode assembly; providing a shell, the shell being provided with a accommodating space for accommodating the electrode assembly; the shell comprising a first side plate located on one side along a first direction; providing a pressure relief mechanism, the pressure relief mechanism being arranged on the first side plate; providing a cover assembly, the cover assembly being used to seal the shell; assembling the electrode assembly, the shell, the pressure relief mechanism and the cover assembly to form a battery cell; wherein providing the shell comprises forming a first flow channel extending along the inner surface of the first side plate of the shell, the first flow channel being used to guide the gas in the accommodating space to the pressure relief mechanism, so that the pressure relief mechanism is actuated and releases the pressure when the pressure reaches a threshold value.

[0026] According to the fifth aspect of the present application, a battery cell manufacturing system is provided, comprising an electrode assembly providing device for providing an electrode assembly; a shell providing device for providing a shell, the shell being provided with a accommodating space for accommodating the electrode assembly; the shell comprising a first side plate located on one side along a first direction; a pressure relief mechanism providing device for providing a pressure relief mechanism, the pressure relief mechanism being arranged on the first side plate; a cover assembly providing device for providing a cover assembly, the cover assembly being used to seal the shell; an assembling device for assembling the electrode assembly, the shell, the pressure relief mechanism and the cover assembly to form a battery cell; wherein a first flow channel extending along the inner surface of the first side plate of the shell is formed, the first flow channel being used to guide the gas in the accommodating space to the pressure relief mechanism, so that the pressure relief mechanism is actuated and releases the pressure when the pressure reaches a threshold value.

[0027] The battery cell and its manufacturing method and manufacturing system, battery and power-consuming device provided in the present application can improve the exhaust efficiency of the battery cell when thermal runaway occurs, and improve the safety of the battery cell. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] The drawings described herein are used to provide a further understanding of the present application and constitute a part of the present application. The illustrative embodiments of the present application and their descriptions are used to explain the present application and do not constitute an improper limitation on the present application. In the drawings:

[0029] Figure 1 A schematic diagram of the structure of a vehicle provided in some embodiments of the present application;

[0030] Figure 2 An exploded schematic diagram of a battery provided in some embodiments of the present application;

[0031] Figure 3 for Figure 2 A schematic diagram of the structure of the battery module shown;

[0032] Figure 4 An exploded schematic diagram of a battery cell provided in some embodiments of the present application;

[0033] Figure 5A schematic diagram of the structure of a battery cell housing provided in some embodiments of the present application;

[0034] Figure 6 for Figure 5 The schematic cross-sectional view of the shell along AA is shown;

[0035] Figure 7 A schematic top view of a battery cell provided in some embodiments of the present application;

[0036] Figure 8 for Figure 7 The method shown in Figure 5 A schematic cross-sectional view of a battery cell of a housing at position BB of an embodiment;

[0037] Fig. 9 for Figure 8 An enlarged schematic diagram of a battery cell at position C shown in FIG.

[0038] Fig.10 for Figure 8 An enlarged schematic diagram of a battery cell at D shown in FIG.

[0039] Fig.11 A schematic structural diagram of a battery cell housing provided in yet another embodiment of the present application;

[0040] Fig.12 A schematic structural diagram of a battery cell housing provided in yet another embodiment of the present application;

[0041] Fig.13 A schematic top view of a battery cell provided in yet another embodiment of the present application;

[0042] Fig.14 for Fig.13 The method shown in Fig.12 A schematic cross-sectional view of a battery cell of a housing at EE of an embodiment;

[0043] Fig.15 for Fig.14 An enlarged schematic diagram of the battery cell at F shown in FIG.

[0044] Fig.16 A schematic structural diagram of a battery cell housing provided in yet another embodiment of the present application;

[0045] Fig.17 A schematic structural diagram of a battery cell housing provided in yet another embodiment of the present application;

[0046] Fig.18 A schematic structural diagram of a battery cell provided with a support member according to another embodiment of the present application;

[0047] Fig.19A schematic structural diagram of a support member for a battery cell provided in yet another embodiment of the present application;

[0048] Fig. 20 A schematic structural diagram of a support member for a battery cell provided in yet another embodiment of the present application;

[0049] Fig.21 A schematic structural diagram of a support member for a battery cell provided in yet another embodiment of the present application;

[0050] Fig. 22 A schematic structural diagram of a battery cell provided with a support member and an insulating film according to another embodiment of the present application;

[0051] Fig.23 An exploded schematic diagram of a support member and an insulating film of a battery cell provided in yet another embodiment of the present application;

[0052] Fig.24 for Fig.23 A schematic top view of the support member and the insulating film after being combined as shown in FIG.

[0053] Fig.25 A schematic diagram of a process for manufacturing a battery cell provided in some embodiments of the present application;

[0054] Fig.26 A schematic block diagram of a battery cell manufacturing system provided for some embodiments of the present application.

[0055] In the drawings, the drawings are not drawn to scale. DETAILED DESCRIPTION

[0056] In order to make the purpose, technical solution and advantages of the embodiments of the present application clearer, the technical solution in the embodiments of the present application will be clearly described below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of this application.

[0057] Unless otherwise defined, all technical and scientific terms used in this application have the same meanings as those commonly understood by technicians in the technical field of this application; the terms used in the specification of this application are only for the purpose of describing specific embodiments and are not intended to limit this application; the terms "including" and "having" in the specification and claims of this application and the above-mentioned drawings and any variations thereof are intended to cover non-exclusive inclusions. The terms "first", "second", etc. in the specification and claims of this application or the above-mentioned drawings are used to distinguish different objects, rather than to describe a specific order or a primary and secondary relationship.

[0058] Reference to "embodiment" in this application means that a particular feature, structure, or characteristic described in conjunction with the embodiment may be included in at least one embodiment of the present application. The appearance of the phrase in various places 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.

[0059] In the description of this application, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected", "connected", and "attached" 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 a direct connection, or an indirect connection through an intermediate medium, or it can be the internal communication of two elements. For ordinary technicians in this field, the specific meanings of the above terms in this application can be understood according to specific circumstances.

[0060] The term "and / or" in this application is only a description of the association relationship of associated objects, indicating that there can be three relationships. For example, A and / or B can represent: A exists alone, A and B exist at the same time, and B exists alone. In addition, the character " / " in this application generally indicates that the associated objects before and after are in an "or" relationship.

[0061] In the embodiments of the present application, the same reference numerals represent the same components, and for the sake of brevity, detailed descriptions of the same components are omitted in different embodiments. It should be understood that the thickness, length, width and other dimensions of various components in the embodiments of the present application shown in the drawings, as well as the overall thickness, length, width and other dimensions of the integrated device are only exemplary descriptions and should not constitute any limitation to the present application.

[0062] The term "plurality" used in the present application refers to two or more (including two).

[0063] 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.

[0064] 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.

[0065] A battery cell includes an electrode assembly and an electrolyte. The electrode assembly includes a positive electrode sheet, a negative electrode sheet and a separator. A 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 current collector and a positive active material layer. The positive active material layer is coated on the surface of the positive current collector; the positive current collector includes a positive current collector and a positive convex portion protruding from the positive current collector. The positive current collector is coated with the positive active material layer. At least part of the positive convex portion is not coated with the positive active material layer. The positive convex portion serves as a positive electrode ear. Taking a lithium-ion battery as an example, the material of the positive current collector may be aluminum, the positive active material layer includes a positive active material, and the positive active material may be lithium cobalt oxide, lithium iron phosphate, ternary lithium or lithium manganese oxide, etc. The negative electrode sheet includes a negative electrode current collector and a negative electrode active material layer, and the negative electrode active material layer is coated on the surface of the negative electrode current collector; the negative electrode current collector includes a negative electrode current collector and a negative electrode protrusion protruding from the negative electrode current collector, the negative electrode current collector is coated with a negative electrode active material layer, at least part of the negative electrode protrusion is not coated with the negative electrode active material layer, and the negative electrode protrusion serves as a negative electrode tab. The material of the negative electrode current collector may be copper, and the negative electrode active material layer includes a negative electrode active material, and the negative electrode active material may be carbon or silicon, etc. In order to ensure that a large current passes without melting, the number of positive electrode tabs is multiple and stacked together, and the number of negative electrode tabs is multiple and stacked together. The material of the separator may be PP (polypropylene, polypropylene) or PE (polyethylene, polyethylene), etc. In addition, the electrode assembly may be a winding structure or a laminated structure, and the embodiments of the present application are not limited thereto.

[0066] The battery cell may further include a housing assembly having a receiving cavity therein, which is a closed space provided by the housing assembly for the electrode assembly and the electrolyte.

[0067] For battery cells, the main safety hazards come from the charging and discharging process, as well as the appropriate ambient temperature design. In order to effectively avoid unnecessary losses, there are generally at least three protection measures for battery cells. Specifically, the protection measures include at least switching elements, selecting appropriate isolation materials, and pressure relief mechanisms. A switching element refers to an element that can stop the battery from charging or discharging when the temperature or resistance in the battery cell reaches a certain threshold. The isolation element is used to isolate the positive and negative pole pieces. When the temperature rises to a certain value, it can automatically dissolve the micron-level (or even nano-level) micropores attached to it, so that metal ions cannot pass through the isolation element, terminating the internal reaction of the battery cell.

[0068] The pressure relief mechanism refers to an element or component that is actuated to release the internal pressure when the internal pressure of the battery cell reaches a predetermined threshold. The threshold design varies according to different design requirements. The threshold may depend on one or more materials of the positive electrode plate, negative electrode plate, electrolyte and separator in the battery cell. The pressure relief mechanism can take the form of an explosion-proof valve, an air valve, a pressure relief valve or a safety valve, and can specifically adopt a pressure-sensitive element or structure, that is, when the internal pressure of the battery cell reaches a predetermined threshold, the pressure relief mechanism performs an action or a weak structure provided in the pressure relief mechanism ruptures, thereby forming an opening or flow channel for the internal pressure or temperature to be released.

[0069] The "actuation" mentioned in this application means that the pressure relief mechanism is in action or activated to a certain state, so that the internal pressure of the battery cell can be released. The action produced by the pressure relief mechanism may include but is not limited to: at least a part of the pressure relief mechanism is ruptured, broken, torn or opened, etc. When the pressure relief mechanism is actuated, the high-temperature and high-pressure substances inside the battery cell will be discharged from the actuated part as emissions. In this way, the battery cell can be depressurized under controllable pressure, thereby avoiding potential more serious accidents.

[0070] The emissions from the battery cells mentioned in this application include, but are not limited to: electrolyte, dissolved or split positive and negative electrode plates, fragments of separators, high-temperature and high-pressure gases produced by the reaction, flames, etc.

[0071] The pressure relief mechanism on the battery cell has an important impact on the safety of the battery cell. For example, when a short circuit or overcharge occurs, thermal runaway may occur inside the battery cell, causing a sudden increase in pressure. In this case, the pressure relief mechanism can be activated to release the internal pressure to the outside to prevent the battery cell from exploding or catching fire.

[0072] The pressure relief mechanism is usually installed in the housing assembly. The inventors found that in order to increase the energy density of the battery cell, the space available for gas flow inside the battery cell is limited, resulting in a low gas discharge rate during thermal runaway. In addition, the pressure relief mechanism may be blocked by components inside the housing assembly, resulting in poor exhaust and causing safety hazards.

[0073] In view of this, an embodiment of the present application provides a technical solution, in which a battery cell includes an electrode assembly, a shell, a pressure relief mechanism and a cover assembly. The shell is provided with a storage space for accommodating the electrode assembly; the shell includes a first side plate located on one side along a first direction; the pressure relief mechanism is arranged on the first side plate; the cover assembly is used to seal the shell; the inner surface of the first side plate of the shell is provided with a first flow channel extending along the inner surface, and the first flow channel is used to guide the gas in the storage space to the pressure relief mechanism, so that the pressure relief mechanism is actuated and releases the pressure when the pressure reaches a threshold. A battery cell with such a structure guides high-temperature and high-pressure gas to the pressure relief mechanism in the event of thermal runaway, thereby increasing the exhaust rate and improving safety performance.

[0074] The technical solutions described in the embodiments of the present application are applicable to batteries and electrical devices using batteries.

[0075] The electrical device may be a vehicle, a mobile phone, a portable device, a laptop computer, a ship, a spacecraft, an electric toy, an electric tool, and the like. The vehicle 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, and the like; the spacecraft may include an airplane, a rocket, a space shuttle, and a spacecraft, and the like; 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, and the like; the electric tool may include a metal cutting electric tool, a grinding electric tool, an assembly electric tool, and an electric tool for railways, such as an electric drill, an electric grinder, an electric wrench, an electric screwdriver, an electric hammer, an impact drill, a concrete vibrator, and an electric planer, and the like. The embodiments of the present application do not impose any special restrictions on the above-mentioned electrical devices.

[0076] For the convenience of description, the following embodiments are described by taking the electric device as a vehicle as an example.

[0077] Figure 1 This is a schematic diagram of the structure of a vehicle provided in some embodiments of the present application. Figure 1 As shown, a battery 2 is disposed inside the vehicle 1, and the battery 2 may be disposed at the bottom, head, or tail of the vehicle 1. The battery 2 may be used to power the vehicle 1, for example, the battery 2 may be used as an operating power source for the vehicle 1.

[0078] The vehicle 1 may further include a controller 3 and a motor 4 , wherein the controller 3 is used to control the battery 2 to supply power to the motor 4 , for example, to meet the power requirements of starting, navigating, and driving the vehicle 1 .

[0079] In some embodiments of the present application, the battery 2 can not only serve as an operating power source for the vehicle 1, but also serve as a driving power source for the vehicle 1, replacing or partially replacing fuel or natural gas to provide driving power for the vehicle 1.

[0080] Figure 2Schematic diagram of an explosion of a battery provided in some embodiments of the present application. Figure 2 As shown, the battery 2 includes a box 5 and a battery cell ( Figure 2 The battery cells are contained in the box body 5.

[0081] The box 5 is used to accommodate the battery cells, and the box 5 can be a variety of structures. In some embodiments, the box 5 can include a first box portion 51 and a second box portion 52, the first box portion 51 and the second box portion 52 cover each other, and the first box portion 51 and the second box portion 52 jointly define a storage space 53 for accommodating the battery cells. The second box portion 52 can be a hollow structure with one end open, the first box portion 51 is a plate-like structure, and the first box portion 51 covers the open side of the second box portion 52 to form a box 5 with a storage space 53; the first box portion 51 and the second box portion 52 can also be a hollow structure with one side open, and the open side of the first box portion 51 covers the open side of the second box portion 52 to form a box 5 with a storage space 53. Of course, the first box portion 51 and the second box portion 52 can be a variety of shapes, such as a cylinder, a cuboid, etc.

[0082] In order to improve the sealing performance after the first box body 51 and the second box body 52 are connected, a sealing member, such as a sealant, a sealing ring, etc., may also be provided between the first box body 51 and the second box body 52 .

[0083] Assuming that the first box body portion 51 covers the top of the second box body portion 52 , the first box body portion 51 can also be referred to as an upper box cover, and the second box body portion 52 can also be referred to as a lower box body.

[0084] In the battery 2, there can be one or more battery cells. If there are multiple battery cells, the multiple battery cells can be connected in series, in parallel, or in mixed connection. Mixed connection means that the multiple battery cells are both connected in series and in parallel. The multiple battery cells can be directly connected in series, in parallel, or in mixed connection, and then the whole formed by the multiple battery cells is accommodated in the box 5; of course, multiple battery cells can also be connected in series, in parallel, or in mixed connection to form a battery module 6, and the multiple battery modules 6 are then connected in series, in parallel, or in mixed connection to form a whole, and accommodated in the box 5.

[0085] Figure 3 for Figure 2 The schematic diagram of the battery module is shown in FIG. Figure 3 As shown, in some embodiments, there are multiple battery cells 7, and the multiple battery cells 7 are first connected in series, in parallel, or in mixed connection to form a battery module 6. The multiple battery modules 6 are then connected in series, in parallel, or in mixed connection to form a whole, and are accommodated in a box.

[0086] The multiple battery cells 7 in the battery module 6 can be electrically connected through a busbar component to achieve parallel connection, series connection or mixed connection of the multiple battery cells 7 in the battery module 6 .

[0087] Figure 4 An exploded schematic diagram of a battery cell provided in some embodiments of the present application.

[0088] like Figure 4 As shown, the battery cell 7 provided in the embodiment of the present application includes an electrode assembly 10 and a housing assembly 20 , and the electrode assembly 10 is accommodated in the housing assembly 20 .

[0089] In some embodiments, the battery cell 7 includes: an electrode assembly 10, a shell 21, a pressure relief mechanism 30 and a cover assembly 22. The shell 21 is provided with a receiving space 216 for receiving the electrode assembly 10; the shell 21 includes a first side plate 212 located on one side along the first direction Z; the pressure relief mechanism 30 is arranged on the first side plate 212; the cover assembly 22 is used to seal the shell 21; the inner surface 2120 of the first side plate 212 of the shell 21 is provided with a first flow channel extending along the inner surface 2120, and the first flow channel is used to guide the gas in the receiving space 216 to the pressure relief mechanism 30, so that the pressure relief mechanism 30 is actuated and releases the pressure when the pressure reaches a threshold.

[0090] In some embodiments, the housing component 20 can also be used to contain electrolyte, such as electrolyte. The housing component 20 can be in various structural forms.

[0091] In some embodiments, the housing assembly 20 may include a shell 21 and a cover assembly 22, wherein the shell 21 is a hollow structure with one side open, and the cover assembly 22 covers the opening of the shell 21 and forms a sealed connection to form a housing cavity for accommodating the electrode assembly 10 and the electrolyte.

[0092] The shell 21 can be in various shapes, such as a cylinder, a cuboid, etc. The shape of the shell 21 can be determined according to the specific shape of the electrode assembly 10. For example, if the electrode assembly 10 is a cylindrical structure, a cylindrical shell can be selected; if the electrode assembly 10 is a cuboid structure, a cuboid shell can be selected.

[0093] In some embodiments, the cover assembly 22 includes an end cover 221, and the end cover 221 covers the opening of the housing 21. The end cover 221 can be of various structures, for example, the end cover 221 is a plate-shaped structure. Figure 4 In the embodiment, the shell 21 is a rectangular parallelepiped structure, the end cover 221 is a plate-shaped structure, and the end cover 221 covers the opening at the top of the shell 21.

[0094] The end cap 221 may be made of an insulating material (e.g., plastic) or a conductive material (e.g., metal). When the end cap 221 is made of a metal material, the cap assembly 22 may further include an insulating plate, which is located on a side of the end cap 221 facing the electrode assembly 10 to insulate and separate the end cap 221 from the electrode assembly 10.

[0095] In some embodiments, the cap assembly 22 may further include an electrode terminal 222, which is mounted on the end cap. There are two electrode terminals 222, which are respectively defined as a positive electrode terminal and a negative electrode terminal, and both the positive electrode terminal and the negative electrode terminal are used to be electrically connected to the electrode assembly 10 to output the electrical energy generated by the electrode assembly 10.

[0096] In other embodiments, the housing assembly 20 may also be other structures, for example, the housing assembly 20 includes a shell 21 and two cover assemblies 22, the shell 21 is a hollow structure with two opposite openings, and one cover assembly 22 is correspondingly covered at one opening of the shell 21 and forms a sealed connection to form a receiving cavity for accommodating the electrode assembly 10 and the electrolyte. In this structure, one cover assembly 22 may be provided with two electrode terminals 222, while the other cover assembly 22 may not be provided with an electrode terminal 222, or each of the two cover assemblies 22 may be provided with one electrode terminal 222.

[0097] In the battery cell 7, the electrode assembly 10 contained in the housing assembly 20 may be one or more. Figure 4 In the embodiment, there are two electrode assemblies 10.

[0098] The electrode assembly 10 includes a positive electrode sheet, a negative electrode sheet and a separator. The electrode assembly 10 can be a wound electrode assembly, a laminated electrode assembly or other forms of electrode assembly.

[0099] In some embodiments, the electrode assembly 10 is a wound electrode assembly. The positive electrode sheet, the negative electrode sheet and the separator are all strip-shaped structures. In the embodiment of the present application, the positive electrode sheet, the separator and the negative electrode sheet can be stacked in sequence and wound more than two times to form the electrode assembly 10.

[0100] In other embodiments, the electrode assembly 10 is a laminated electrode assembly. Specifically, the electrode assembly 10 includes a plurality of positive electrode sheets and a plurality of negative electrode sheets, and the positive electrode sheets and the negative electrode sheets are alternately stacked, and the stacking direction is parallel to the thickness direction of the positive electrode sheets and the thickness direction of the negative electrode sheets.

[0101] From the appearance of the electrode assembly 10, the electrode assembly 10 includes a main body 11 and a tab 12 connected to the main body. Exemplarily, the main body extends from one end of the main body close to the cap assembly.

[0102] In some embodiments, there are two pole lugs 12, which are defined as a positive pole lug and a negative pole lug. The positive pole lug and the negative pole lug can extend from the same end of the main body 11, or from opposite ends of the main body 11.

[0103] The main body 11 is the core part of the electrode assembly 10 to realize the charging and discharging functions, and the pole ear part 12 is used to lead the current generated by the main body 11. The main body 11 includes a positive current collector of a positive current collector, a positive active material layer, a negative current collector of a negative current collector, a negative active material layer, and a separator. The positive pole ear part includes a plurality of positive pole ears, and the negative pole ear part includes a plurality of negative pole ears.

[0104] The pole ear portion 12 is used to be electrically connected to the electrode terminal 222. The pole ear portion 12 can be directly connected to the electrode terminal 222 by welding or the like, or can be indirectly connected to the electrode terminal 222 by other components. For example, the battery cell 7 also includes a current collecting component 13, which is used to electrically connect the electrode terminal 222 and the pole ear portion 12. There are two current collecting components 13, and the two current collecting components 13 are respectively defined as a positive current collecting component and a negative current collecting component. The positive current collecting component is used to electrically connect the positive electrode terminal and the positive pole ear portion, and the negative current collecting component is used to electrically connect the negative electrode terminal and the negative pole ear portion. When the battery cell 7 is provided with a plurality of electrode assemblies 10, the positive current collecting components of the plurality of electrode assemblies 10 can be provided as one piece, and the negative current collecting components of the plurality of electrode assemblies 10 can be provided as one piece.

[0105] The first side plate 212 is located at one side of the housing assembly 20 along the first direction Z. The housing 21 of the housing assembly 20 has an end opening at the other side along the first direction Z opposite to the first side plate 212 .

[0106] When the shell 21 is a hollow structure with one end open, the first side plate 212 is a bottom plate of the shell 21 located on a side of the electrode assembly 10 away from the cap assembly 22 .

[0107] The pressure relief mechanism 30 is disposed on the first side plate 212. The pressure relief mechanism 30 may be a part of the first side plate 212, or may be a separate structure from the first side plate 212. The first side plate 212 is provided with a pressure relief hole 210 that penetrates along its thickness direction, and the pressure relief mechanism 30 is fixed to the first side plate 212 by welding or the like and covers the pressure relief hole 210. The pressure relief mechanism 30 seals the pressure relief hole 210 to separate the space inside and outside the first side plate 212 to prevent the electrolyte from flowing out through the pressure relief hole 210 during normal operation.

[0108] The pressure relief mechanism 30 is used to actuate to release the internal pressure when the internal pressure of the battery cell 7 reaches a threshold value. When the gas generated by the battery cell 7 is too much so that the internal pressure of the housing 21 increases and reaches the threshold value, the pressure relief mechanism 30 is actuated or the weak structure provided in the pressure relief mechanism 30 is broken, and the gas and other high-temperature and high-pressure substances are released outward through the cracked opening of the pressure relief mechanism 30 and the pressure relief hole 210, thereby preventing the battery cell 7 from exploding.

[0109] The pressure relief mechanism 30 may be any possible pressure relief structure, which is not limited in the present embodiment. For example, the pressure relief mechanism 30 may be a pressure-sensitive pressure relief mechanism, which is configured to rupture when the internal air pressure of the battery cell 7 provided with the pressure-sensitive pressure relief mechanism reaches a threshold.

[0110] In some embodiments, notches, grooves or other structures are formed on the pressure relief mechanism 30 to reduce the local strength of the pressure relief mechanism 30 and form a weak structure on the pressure relief mechanism 30; when the internal pressure of the battery cell 7 reaches a threshold value, the pressure relief mechanism 30 ruptures at the weak structure, and the pressure relief mechanism 30 is folded along the portion set at the rupture to form an opening to release high-temperature and high-pressure substances.

[0111] When short circuit, overcharging and the like occur, the battery cell 7 undergoes thermal runaway and releases a large amount of high-temperature and high-pressure substances, such as high-temperature and high-pressure gas; the first flow channel can guide the gas flow to guide the gas in the accommodating space 216 to the pressure relief mechanism 30, and the gas acts on the pressure-bearing surface of the pressure relief mechanism 30 and applies pressure to the pressure relief mechanism 30; as the amount of gas increases, the pressure on the pressure relief mechanism 30 becomes greater, and the pressure relief mechanism 30 is actuated when the pressure reaches a threshold value to discharge the gas and other high-temperature and high-pressure substances to the outside of the battery cell 7, thereby releasing the internal pressure of the battery cell 7 outward to prevent the battery cell 7 from exploding or catching fire.

[0112] The embodiment of the present application sets a first flow channel 2151 on the first side plate 212 of the shell 21, so as to guide the gas released by the battery cell 7 during thermal runaway from the accommodating space 216 to the pressure relief mechanism 30, so that the pressure relief mechanism 30 can be actuated and release the gas in time, thereby improving the exhaust rate of the battery cell 7 during thermal runaway and improving the safety of the battery cell 7.

[0113] Figure 5 A schematic diagram of the structure of a battery cell housing provided in some embodiments of the present application; Figure 6 for Figure 5 The schematic cross-sectional view of the shell along AA is shown; Figure 7 A schematic top view of a battery cell provided in some embodiments of the present application; Figure 8 for Figure 7 The method shown in Figure 5A schematic cross-sectional view of a battery cell of a housing at position BB of an embodiment; Fig. 9 for Figure 8 An enlarged schematic diagram of a battery cell at position C shown in FIG. Fig.10 for Figure 8 An enlarged schematic diagram of the battery cell shown in FIG.

[0114] Reference Figures 5 to 10 In some embodiments, the first flow channel 2151 includes a plurality of first grooves 2141 disposed on and extending along the inner surface 2120 of the first side plate 212, and one end of each first groove 2141 is connected to the pressure relief mechanism 30. The first flow channel 2151 is configured as a plurality of first grooves 2141, and each first groove 2141 is connected to the pressure relief mechanism 30. When the battery cell 7 is in thermal runaway, the released gas can be guided from the accommodation space 216 to the pressure relief mechanism 30 along the first grooves 2141 to be discharged, thereby increasing the exhaust rate when the battery cell 7 is in thermal runaway and improving the safety of the battery cell 7. At the same time, the first grooves 2141 are disposed on the inner surface of the first side plate 212, and will not occupy the accommodation space 216 to affect the energy density of the battery cell 7.

[0115] Reference Figure 5 and Figure 6 In some embodiments, the plurality of first grooves 2141 are parallel to each other and spaced apart from each other. In some embodiments, each first groove 2141 extends along a third direction Y, which is perpendicular to the first direction Z; and the plurality of first grooves 2141 are arranged along a second direction X, which is perpendicular to the first direction Z and the third direction Y.

[0116] In some embodiments, along the second direction X, the plurality of first grooves 2141 may have the same or different widths as each other. In some embodiments, along the first direction Z, the plurality of first grooves 2141 may have the same or different depths as each other.

[0117] The housing 21 includes a pair of second side panels 213 disposed opposite to each other along the third direction Y, and a pair of third side panels 211 disposed opposite to each other along the second direction X. The second side panels 213 and the third side panels 211 are both connected to the first side panels 212, and adjacent second side panels 213 and third side panels 211 are also connected to form a receiving space 216.

[0118] One end of the plurality of first grooves 2141 is communicated with the pressure relief hole 210 , and the other end thereof extends to a position close to the second side plate 213 .

[0119] Reference Figures 7 to 10The accommodation space 216 includes a first gap G1 provided between the electrode assembly 10 and each second side plate 213. The first flow channel 2151 is connected to the first gap G1. The first flow channel 2151 is connected to the accommodation space 216 by being connected to the first gap G1. In addition, the gas generated inside the electrode assembly 10 can also directly enter the pressure relief mechanism 30 from the first flow channel 2151.

[0120] Reference Fig. 9 A first gap G1 is formed between the electrode assembly 10 and each second side plate 213, and a plurality of first grooves 2141 constituting the first flow channel 2151 extend to the vicinity of the adjacent second side plate 213 in the third direction Y, pass over the lower edge of the electrode assembly 10 in the third direction Y, and communicate with the first gap G1. Furthermore, when too much gas is generated by the battery cell 7, causing the internal pressure of the housing 21 to rise and reach a threshold, the gas, after passing through the first gap G1, can be unobstructed by the electrode assembly 10, and can move to the pressure relief mechanism 30 through the plurality of first grooves 2141 to be discharged. In addition, the gas generated inside the electrode assembly 10 can also directly enter the pressure relief mechanism 30 through the first flow channel 2151, thereby improving the exhaust efficiency.

[0121] In some embodiments, a first gap G1 is formed between the electrode assembly 10 and each second side plate 213 , and a plurality of first grooves 2141 connect the first gaps G1 and the pressure relief mechanism 30 on both sides in the third direction Y, respectively.

[0122] Reference Fig.10 As shown, in some embodiments, starting from the position where the first flow channel 2151 is connected to the pressure relief mechanism 30 , the depth H of at least a portion of the length of the first flow channel 2151 gradually decreases in a direction away from the pressure relief mechanism 30 .

[0123] Specifically, starting from the position where the first flow channel 2151 is connected to the pressure relief mechanism 30, the depth H of each first groove 2141 constituting the first flow channel 2151 gradually decreases along the direction away from the pressure relief mechanism 30 over at least a portion of the length along the third direction Y. Fig.10 As shown in , the depth H of at least a portion of the first groove 2141 gradually increases in the direction close to the pressure relief mechanism 30, forming a slope inclined toward the exhaust direction of the pressure relief mechanism 30, which is more conducive to guiding the gas to the pressure relief mechanism 30 for discharge, thereby improving the exhaust efficiency. The slope can be inclined in a straight line or an arc.

[0124] Partial length means that the portion where the depth H changes only occupies a portion of the length of the first flow channel 2151 connected to the pressure relief mechanism 30 in the third direction Y, and the depth of the remaining portion of the first flow channel 2151 can remain unchanged. In other embodiments, the first flow channel 2151 can also have a depth H that changes over the entire length of the first flow channel 2151.

[0125] The position where the first flow channel 2151 is connected to the pressure relief mechanism 30 refers to the position where the first flow channel 2151 is connected to the edge of the pressure relief mechanism 30. When the housing 21 is provided with a pressure relief hole 210, the position where the first flow channel 2151 is connected to the pressure relief mechanism 30 refers to the position where the first flow channel 2151 is connected to the pressure relief hole 210.

[0126] Fig.11 A schematic structural diagram of a battery cell shell provided in yet another embodiment of the present application.

[0127] Reference Fig.11 In the embodiment, Fig.11 The housing 21 and Figure 5 The difference between the shell 21 of the embodiment is that a plurality of first grooves 2141 extend in a divergent manner around the pressure relief mechanism 30 and are spaced apart from each other.

[0128] Specifically, a plurality of first grooves 2141 together form a first flow channel 2151, and the plurality of first grooves 2141 extend in a divergent manner around the pressure relief mechanism 30 as the center and are spaced from each other. Extending in a divergent manner means that the plurality of first grooves 2141 are centered on the pressure relief mechanism 30, and the plurality of first grooves 2141 extend approximately in a radial direction with the center of the pressure relief mechanism 30 as the axis. One end of the plurality of first grooves 2141 is connected to the pressure relief mechanism 30, and in some embodiments, the plurality of first grooves 2141 are connected to the pressure relief hole 210. The other end of a portion of the first grooves 2141 extends to the vicinity of the adjacent second side plate 213, and the other end of a portion of the first grooves 2141 extends to the vicinity of the third side plate 211.

[0129] In this embodiment, the accommodating space 216 includes a first gap G1 provided between the electrode assembly 10 and each second side plate 213, and a portion of the first groove 2141 extending to the vicinity of the adjacent second side plate 213 is connected to the first gap G1. The accommodating space 216 also includes a second gap G2 provided between the electrode assembly 10 and each third side plate 211, and a portion of the first groove 2141 extending to the vicinity of the third side plate 211 is connected to the second gap G2. In this way, when the battery cell 7 has a thermal runaway, the gas can be guided to the pressure relief mechanism 30 along the first flow channel 2151 through the first gap G1 and the second gap G2 in the circumferential direction of the pressure relief mechanism 30. In addition, the gas generated inside the electrode assembly 10 can also directly enter the pressure relief mechanism 30 through the first flow channel 2151. The exhaust rate when the battery cell 7 has a thermal runaway is increased, and the safety of the battery cell 7 is improved.

[0130] Fig.12 A schematic structural diagram of a battery cell housing provided in yet another embodiment of the present application; Fig.13 A schematic top view of a battery cell provided in yet another embodiment of the present application; Fig.14 for Fig.13 The method shown in Fig.12 A schematic cross-sectional view of a battery cell of a housing at EE of an embodiment; Fig.15 for Fig.14 An enlarged schematic diagram of the battery cell at F shown in FIG.

[0131] Reference Figure 12-15 As shown in , in some embodiments, in the housing 21, a protrusion 2142 protruding toward the accommodating space 216 is formed on the inner surface of the first side plate 212, the protrusion 2142 has a top surface 2140 away from the inner surface 2120, and the first flow channel 2152 is formed in the space between the top surface 2140 and the inner surface 2120 of the protrusion 2142. In this embodiment, the top surface 2140 of the protrusion 2142 is used to support the electrode assembly 10, and the first flow channel 2152 is formed in the space between the top surface 2140 and the inner surface 2120 of the protrusion 2142, which can improve the exhaust rate when the battery cell 7 is in thermal runaway, thereby improving the safety of the battery cell 7.

[0132] In some embodiments, reference Fig.12 As shown in the figure, the first flow channel 2152 includes a plurality of branch flow channels 21521 connected to the pressure relief mechanism 30; there are a plurality of protrusions 2142, and the plurality of protrusions 2142 extend in a divergent shape around the pressure relief mechanism 30 and are spaced apart from each other, and a branch flow channel 21521 is formed between two adjacent protrusions 2142 and the inner surface 2120. The plurality of protrusions 2142 extend in a divergent shape around the pressure relief mechanism 30 and are spaced apart from each other, which is beneficial to improving the exhaust efficiency in the circumferential direction of the pressure relief mechanism 30.

[0133] Specifically, a flow divider 21521 is formed between two adjacent protrusions 2142 and the inner surface 2120, and a plurality of flow dividers 21521 extend in a divergent manner around the pressure relief mechanism 30 and are spaced from each other. Extending in a divergent manner means that a plurality of flow dividers 21521 are centered on the pressure relief mechanism 30, and the plurality of flow dividers 21521 extend approximately in a radial direction with the center point of the pressure relief mechanism 30 as the axis. One end of the plurality of flow dividers 21521 is connected to the pressure relief mechanism 30, and in some embodiments, the plurality of flow dividers 21521 are connected to the pressure relief hole 210. The other end of a portion of the flow dividers 21521 extends to the vicinity of a second side plate 213 and is connected to the first gap G1; the other end of a portion of the flow dividers 21521 extends to the vicinity of a third side plate 211 and is connected to the second gap G2.

[0134] In this embodiment, the accommodation space 216 includes a first gap G1 provided between the electrode assembly 10 and each second side plate 213, and a portion of the flow channel 21521 extending to the vicinity of one second side plate 213 is connected to the first gap G1. Fig.14 and 15 As shown in , the accommodating space 216 also includes a second gap G2 set between the electrode assembly 10 and each third side plate 211, and a portion of the shunt channel 21521 extending to the vicinity of a third side plate 211 is connected to the second gap G2. In this way, when the battery cell 7 has a thermal runaway, the gas can be guided to the pressure relief mechanism 30 along the first flow channel 2152 in the circumferential direction of the pressure relief mechanism 30. In addition, the gas generated inside the electrode assembly 10 can also directly enter the pressure relief mechanism 30 through the first flow channel 2152. Improve the exhaust rate when the battery cell 7 is in thermal runaway, and improve the safety of the battery cell 7.

[0135] also, Fig.11 and Fig.12 In the embodiments, reference can also be made to Fig.10 In an embodiment, starting from the position where the first flow channel 2151 is connected to the pressure relief mechanism 30, the depth H of at least a portion of the length of the first flow channel 2151 gradually decreases in a direction away from the pressure relief mechanism 30.

[0136] Fig.16 A schematic structural diagram of a battery cell shell provided in yet another embodiment of the present application.

[0137] Reference Fig.16As shown in, in some embodiments, in the shell 21, the first flow channel 2153 includes a plurality of branch flow channels 21531 and a connecting flow channel 21532; there are a plurality of protrusions 2143, each of which extends substantially along the second direction X of the first side plate 212; a plurality of protrusions 2143 are arranged at intervals and spaced from each other along the third direction Y of the first side plate 212; a branch flow channel 21531 is formed between two adjacent protrusions 2143 and the inner surface 2120, and two adjacent branch flow channels 21531 are connected through the connecting flow channel 21532; at least one of the branch flow channels 21531 is connected to the pressure relief mechanism 30 through the connecting flow channel 21532; the second direction X is perpendicular to the first direction Z; the third direction Y is perpendicular to the first direction Z and the second direction X. By providing the protrusion 2143 extending along the second direction X of the first side plate 212, a flow channel 21531 is formed between two adjacent protrusions 2143 and the inner surface 2120, and the flow channel 21531 is connected to the pressure relief mechanism 30 through the connecting flow channel 21532, so that the exhaust efficiency in the second direction X can be improved. When the width of the housing 21 in the second direction X is close to the length in the third direction Y, the first flow channel 2153 of this embodiment can provide a better exhaust effect.

[0138] In this embodiment, a third gap G3 is provided between one end of each protrusion 2143 in the second direction X and the adjacent second side plate 213, and the third gap G3 forms at least a portion of the connecting flow channel 21532. The connecting flow channel 21532 extends as a whole along the third direction Y. By providing the third gap G3 to form a portion of the connecting flow channel that connects the branch flow channel 21531 to the pressure relief mechanism 30, the gas in the branch flow channel 21531 can be quickly guided to the pressure relief mechanism 30 through the connecting flow channel 21532 for discharge.

[0139] Fig.17 A schematic structural diagram of a battery cell shell provided in yet another embodiment of the present application.

[0140] Reference Fig.17 As shown in Fig.16The difference between the embodiment in the embodiment is that, in the housing 21, at least one protrusion 2144 includes a plurality of sub-protrusions 21441, and the sub-protrusions 21441 are arranged at intervals along the second direction X, and a fourth gap G4 is formed between adjacent sub-protrusions 21441, and the fourth gap G4 also forms at least a part of the connecting flow channel 21532, that is, in this embodiment, the connecting flow channel 21532 includes a side connecting flow channel 21533 of which the third gap G3 is a part and an intermediate connecting flow channel 21534 of which the fourth gap G4 is a part. The intermediate connecting flow channel 21534 that connects the branch flow channel 21531 to the pressure relief mechanism is formed by setting the fourth gap G4, and the intermediate connecting flow channel 21534 cooperates with the side connecting flow channel 21533 to quickly guide the gas in the branch flow channel 21531 to the pressure relief mechanism 30 for discharge through the connecting flow channel 21532.

[0141] Optionally, in Fig.16 , 17 In the illustrated embodiment, the protrusion 2143 or the protrusion 2144 is configured to be an arc or a folded line protruding in a direction away from the pressure relief mechanism 30 in the third direction Y. The arc or folded line protrusion 2143 or the protrusion 2144 protruding in a direction away from the pressure relief mechanism 30 in the third direction Y can guide the airflow toward the pressure relief mechanism 30 during exhaust, which is beneficial for rapid exhaust of gas.

[0142] In the above embodiments, an insulating layer may also be provided on the top surface 2140 of the protrusion 2143 or the protrusion 2144, and the insulating layer is used to achieve insulation between the electrode assembly 10 and the shell 21. No additional supporting structure is required, which reduces the occupancy of the accommodating space 216 and is beneficial to improving the energy density of the battery cell 7 without affecting the exhaust of the battery cell 7.

[0143] Fig.18 A schematic structural diagram of a battery cell provided in yet another embodiment of the present application.

[0144] Reference Fig.18 As shown in , in this embodiment, the difference from the above embodiment is that a support member 40 is added. The support member 40 is disposed between the electrode assembly 10 and the first side plate 212 and is used to support the electrode assembly 10. The electrode assembly 10, the support member 40 and the first side plate 212 are arranged in sequence along the first direction Z. Exemplarily, the support member 40 is made of an insulating material, which can insulate and separate the first side plate 212 and the electrode assembly 10. The support member 40 can support the electrode assembly 10 to reduce the shaking of the electrode assembly 10 when the battery cell 7 vibrates, and reduce the risk of the active material of the electrode assembly 10 falling off.

[0145] The support member 40 may directly abut against the electrode assembly 10 to support the electrode assembly 10, or may support the electrode assembly 10 through other members. For example, the battery cell 7 further includes an insulating film coated on the outside of the main body 11 of the electrode assembly 10, a portion of the insulating film is located between the support member 40 and the electrode assembly 10, and the support member 40 supports the electrode assembly 10 through the insulating film. The support member 40 has a first surface 41 and a second surface 42 that are arranged opposite to each other, the first surface 41 faces the first side plate 212, and the second surface 42 faces the electrode assembly 10.

[0146] In some embodiments, the support member 40 may be against the first side plate 212, for example, Figure 5-11 In the embodiment of the present invention, the support member 40 may be pressed against the first side plate 212 under the gravity of the electrode assembly 10 and contact the inner surface 2120 of the first side plate 212. Fig. 9 and Fig.10 In the embodiment of the present invention, a first flow channel is formed between the first surface 41 of the support member 40 and the first groove 2141 between the first side plate 212. Fig. 9 The support member 40 forms a fifth gap G5 with the second side plate 213 in the third direction Y. Fig.15 In the embodiment, the support member 40 forms a sixth gap G6 with the adjacent third side plate 211 in the second direction X. The first gap G1 is connected to the first flow channel 2151 through the fifth gap G5. The second gap G2 is connected to the first flow channel 2151 through the sixth gap G6.

[0147] The support member 40 may also be spaced apart from the first side plate 212 in the first direction Z. Figure 12-17 In the embodiment, the support member 40 can be placed on the surface of the protrusion 2142, 2143 or 2144 and spaced apart from the inner surface 2120 of the first side plate 212. The first flow channel 2152 or 2153 is formed between the first surface 41 of the support member 40 and the inner surface 2120 of the first side plate 212.

[0148] Fig.19 A schematic structural diagram of a support member for a battery cell provided in yet another embodiment of the present application; Fig. 20 A schematic structural diagram of a support member for a battery cell provided in yet another embodiment of the present application; Fig.21 A schematic structural diagram of a support structure of a battery cell provided in yet another embodiment of the present application.

[0149] In some embodiments, a second flow channel is provided on the support member 40, and the second flow channel connects the first flow channel 2151, 2152 or 2153 and the accommodation space 216. Forming the second flow channel on the support member 40, connecting the first flow channel 2151, 2152 or 2153 and the accommodation space 216, can increase the flow channel area of ​​the exhaust gas and improve the exhaust efficiency.

[0150] Reference Fig.19 As shown, in some embodiments, the second flow channel includes a first through hole 402 that penetrates the support member 40 along the first direction Z, and the first through hole 402 connects the first flow channel 2151 , 2152 or 2153 and the accommodating space 216 in the first direction Z.

[0151] Reference Fig. 20 As shown, in some embodiments, the second flow channel includes a second groove 401 provided on the first surface 41, the second groove 401 is connected to the first gap G1 and / or the second gap G2, and the second groove 401 is connected to the first flow channel. By providing the second groove 401 connected to the first gap G1 and / or the second gap G2 and the first flow channel 2151, 2152 or 2153 on the support member 40, the flow channel area of ​​the exhaust gas can be increased, and the exhaust efficiency can be improved.

[0152] Specifically, the second groove 401 can be formed as a groove that passes through the second direction X and / or the third direction Y, and the second groove 401 extends to the edge of the support member 40 in the second direction X and / or the third direction Y. The second groove 401 is connected to the fifth gap G5 and / or the sixth gap G6, and is connected to the accommodating space 216 through the fifth gap G5 and / or the sixth gap G6.

[0153] Reference Fig.21 As shown, in some embodiments, a first through hole 402 and a second groove 401 are provided on the support member 40, and the first through hole 402 is connected to the second groove 401. The flow channel area of ​​the exhaust gas can be further increased, and the exhaust gas efficiency can be improved.

[0154] Fig. 22 A schematic structural diagram of a battery cell provided with a support member and an insulating film according to another embodiment of the present application; Fig.23 An exploded schematic diagram of a support member and an insulating film of a battery cell provided in yet another embodiment of the present application; Fig.24 for Fig.23 Schematic top view of the support member and the insulating film after being combined.

[0155] Reference Figure 22 to Figure 24As shown in , in some embodiments, the battery cell 7 further includes an insulating film 50 coated on the outside of the main body 11 of the electrode assembly 10, a portion of the insulating film 50 is located between the support member 40 and the electrode assembly 10, and the support member 40 supports the electrode assembly 10 through the insulating film 50. The support member 40 has a first surface 41 and a second surface 42 that are oppositely disposed, the first surface 41 faces the first side plate 212, and the second surface 42 faces the insulating film 50.

[0156] In some embodiments, the insulating film 50 is used to wrap a portion of the electrode assembly 10 and separate the electrode assembly 10 from the housing 21; the insulating film 50 includes a first side film 501 located between the electrode assembly 10 and the support member 40; the first side film 501 has a second through hole 5011, and the second through hole 5011 and the first through hole 402 of the support member 40 do not overlap in the first direction Z. The second through hole 5011 of the first side film 500 of the insulating film 50 and the first through hole 402 on the support member 40 do not overlap in the first direction Z, which can avoid direct contact between the electrode assembly 10 and the first side plate 212 of the housing 21, and can achieve reliable insulation between the electrode assembly 10 and the first side plate 212, while realizing the communication between the accommodating space 216 and the first flow channel 2151, 2152 or 2153 through the first through hole 402 and the second through hole 5011, thereby improving the exhaust efficiency.

[0157] In some embodiments, reference Fig.23 and Fig. 9 As shown in , the first side film 501 is located on one side of the insulating film 50 in the first direction Z. The insulating film 50 is provided with a third side film 502 arranged opposite to each other in the third direction Y, and an opening 510 is provided at a position of the third side film 502 close to the first side film 501. The gas generated in the electrode assembly 10 wrapped by the insulating film 50 can be connected to the first flow channel 2151, 2152 or 2153 through the second through hole 5011 and the first through hole 402 on the one hand, and can be connected to the first flow channel 2151, 2152 or 2153 through the opening 510 and the first gap G1 and the third gap G3 on the other hand, and then discharged through the pressure relief mechanism 30, which can increase the flow channel area of ​​the exhaust gas and improve the exhaust efficiency.

[0158] Fig.25 A schematic flow chart of a method for manufacturing a battery cell provided in some embodiments of the present application.

[0159] like Fig.25 As shown, the manufacturing method of the battery cell of the embodiment of the present application includes:

[0160] S100, providing an electrode assembly;

[0161] S200, providing a housing, wherein the housing is provided with a housing space for housing the electrode assembly; the housing includes a first side plate located at one side along a first direction;

[0162] S300, providing a pressure relief mechanism, wherein the pressure relief mechanism is disposed on the first side plate;

[0163] S400, providing a cover assembly, where the cover assembly is used to seal the housing;

[0164] S500, assembling the electrode assembly, the housing, the pressure relief mechanism and the cover assembly to form a battery cell;

[0165] Among them, the step S200 of providing the shell also includes forming a first flow channel extending along the inner surface of the first side plate of the shell, and the first flow channel is used to guide the gas in the accommodating space to the pressure relief mechanism so that the pressure relief mechanism is actuated and releases pressure when the pressure reaches a threshold.

[0166] It should be noted that the relevant structure of the battery cell manufactured by the above-mentioned method for manufacturing the battery cell can refer to the battery cell provided in the above-mentioned embodiments.

[0167] When assembling a battery cell based on the above-mentioned manufacturing method of a battery cell, it is not necessary to perform the above-mentioned steps in sequence, that is, the steps can be performed in the order mentioned in the embodiment, or in a different order from the order mentioned in the embodiment, or several steps can be performed simultaneously. For example, steps S100, S200, S300, and S400 can be performed in any order and can be performed simultaneously.

[0168] Fig.26 A schematic block diagram of a battery cell manufacturing system provided for some embodiments of the present application.

[0169] like Fig.26 As shown, the manufacturing system 8 of the battery cell of the embodiment of the present application includes: an electrode assembly providing device 81, used to provide an electrode assembly; a shell providing device 82, used to provide a shell, the shell is provided with a accommodating space for accommodating the electrode assembly; the shell includes a first side plate located on one side along a first direction; a pressure relief mechanism providing device 83, used to provide a pressure relief mechanism, the pressure relief mechanism is arranged on the first side plate; a cover assembly providing device 84, used to provide a cover assembly, the cover assembly is used to seal the shell; an assembling device 85, used to assemble the electrode assembly, the shell, the pressure relief mechanism and the cover assembly to form a battery cell; wherein, a first flow channel extending along the inner surface of the first side plate of the shell is formed, and the first flow channel is used to guide the gas in the accommodating space to the pressure relief mechanism, so that the pressure relief mechanism is actuated and releases the pressure when the pressure reaches a threshold value.

[0170] The relevant structure of the battery cells manufactured by the above manufacturing system can refer to the battery cells provided in the above embodiments.

[0171] It should be noted that, in the absence of conflict, the embodiments and features in the embodiments of the present application may be combined with each other.

[0172] 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 it. 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 make equivalent replacements for some of the technical features therein, but these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present application.

Claims

1. A battery cell, comprising Electrode assembly; A shell having a receiving space for receiving the electrode assembly; the shell comprises a first side plate located at one side along a first direction; A pressure relief mechanism, arranged on the first side plate; a cover assembly for sealing the housing; in, A first flow channel extending along the inner surface of the first side plate of the housing is provided, the first flow channel being used to guide the gas in the accommodating space to the pressure relief mechanism so that the pressure relief mechanism is actuated and releases the pressure when the pressure reaches a threshold value; The first flow channel includes a plurality of first grooves disposed on and extending along the inner surface of the first side plate, one end of each of the first grooves being connected to the pressure relief mechanism, or, A protrusion protruding toward the accommodation space is formed on the inner surface of the first side plate, the protrusion has a top surface away from the inner surface, and the first flow channel is formed in a space between the top surface of the protrusion and the inner surface.

2. The battery cell according to claim 1, wherein: The plurality of first grooves are parallel to each other; or The plurality of first grooves extend radiating around the pressure relief mechanism.

3. The battery cell according to claim 1, wherein: The first flow channel includes a plurality of branch channels connected to the pressure relief mechanism; there are a plurality of protrusions, and the plurality of protrusions extend divergently around the pressure relief mechanism and are spaced apart from each other, forming a branch channel between two adjacent protrusions and the inner surface.

4. The battery cell according to claim 1, wherein: The first flow channel includes a plurality of branch flow channels and a connecting flow channel; there are a plurality of protrusions, each of which extends substantially along the second direction of the first side plate; the plurality of protrusions are arranged at intervals and spaced from each other along the third direction of the first side plate; a branch flow channel is formed between two adjacent protrusions and the inner surface, and two adjacent branch flow channels are connected through the connecting flow channel; at least one of the branch flow channels is connected to the pressure relief mechanism through the connecting flow channel; the second direction is perpendicular to the first direction; the third direction is perpendicular to the first direction and the second direction.

5. The battery cell according to claim 4, wherein: The housing comprises a pair of second side plates arranged opposite to each other along the second direction; A third gap is provided between an end portion of each of the protrusions in the second direction and an adjacent second side plate, and the third gap forms at least a portion of the connecting flow channel.

6. The battery cell according to claim 4 or 5, wherein: At least one protrusion includes a plurality of sub-protrusions, and the plurality of sub-protrusions are arranged at intervals along the second direction. A fourth gap is formed between adjacent sub-protrusions, and the fourth gap forms at least a portion of the connecting flow channel.

7. The battery cell according to any one of claims 1, 3 to 6, wherein: The protrusion is configured to be in an arc shape or a broken line shape that protrudes in the third direction away from the pressure relief mechanism.

8. The battery cell according to any one of claims 1, 3 to 6, wherein: An insulating layer is disposed on the top surface of the protrusion.

9. The battery cell according to any one of claims 1 to 8, wherein: The housing includes a pair of second side plates arranged opposite to each other along a second direction, and the accommodation space includes a first gap arranged between the electrode assembly and each of the second side plates; the second direction is perpendicular to the first direction; The housing further comprises a pair of third side plates arranged opposite to each other along a third direction, and the accommodation space further comprises a second gap arranged between the electrode assembly and each of the third side plates; the third direction is perpendicular to the first direction and the second direction; The first flow channel is communicated with the first gap and / or the second gap.

10. The battery cell according to any one of claims 1 to 9, wherein: Starting from the position where the first flow channel is connected to the pressure relief mechanism, the depth of at least a portion of the length of the first flow channel gradually decreases in a direction away from the pressure relief mechanism.

11. The battery cell according to any one of claims 1 to 10, wherein: Also includes: a supporting member, disposed between the first side plate and the electrode assembly to support the electrode assembly; The supporting member is provided with a second flow channel, and the second flow channel is connected with the first flow channel and the accommodating space.

12. The battery cell according to claim 11, wherein: The second flow channel includes a first through hole that penetrates the supporting member along the first direction, and the first through hole communicates with the first flow channel and the accommodation space.

13. The battery cell according to claim 11 or 12, wherein: The housing includes a pair of second side plates arranged opposite to each other along a second direction, and the accommodation space includes a first gap arranged between the electrode assembly and each of the second side plates; the second direction is perpendicular to the first direction; The housing further comprises a pair of third side plates arranged opposite to each other along a third direction, and the accommodation space further comprises a second gap arranged between the electrode assembly and each of the third side plates; the third direction is perpendicular to the first direction and the second direction; The support member has a first surface and a second surface that are oppositely disposed, the first surface faces the first side plate, and the second surface faces the electrode assembly; The second flow channel includes a second groove provided on the first surface, the second groove is communicated with the first gap and / or the second gap, and the second groove is communicated with the first flow channel.

14. The battery cell according to claim 12, wherein: Also includes: an insulating film, for wrapping a portion of the electrode assembly and separating the electrode assembly from the housing; the insulating film comprises a first side film located between the electrode assembly and the support member; The first side film has a second through hole, and the second through hole and a projection of the first through hole of the supporting member in the first direction do not overlap.

15. A battery comprising the battery cell according to any one of claims 1 to 14.

16. An electrical device comprising the battery according to claim 15.

17. A method for manufacturing a battery cell, comprising: providing an electrode assembly; A shell is provided, wherein the shell is provided with a receiving space for receiving the electrode assembly; the shell comprises a first side plate located at one side along a first direction; Providing a pressure relief mechanism, wherein the pressure relief mechanism is disposed on the first side plate; providing a cover assembly, the cover assembly being used to seal the housing; Assembling the electrode assembly, the housing, the pressure relief mechanism, and the cap assembly to form the battery cell; Wherein, providing the shell includes forming a first flow channel extending along the inner surface of the first side plate of the shell, the first flow channel being used to guide the gas in the accommodating space to the pressure relief mechanism, so that the pressure relief mechanism is actuated and releases the pressure when the pressure reaches a threshold value; The first flow channel includes a plurality of first grooves disposed on and extending along the inner surface of the first side plate, one end of each of the first grooves being connected to the pressure relief mechanism, or, A protrusion protruding toward the accommodation space is formed on the inner surface of the first side plate, the protrusion has a top surface away from the inner surface, and the first flow channel is formed in a space between the top surface of the protrusion and the inner surface.

18. A battery cell manufacturing system, comprising: An electrode assembly providing device, used for providing an electrode assembly; A shell providing device, used for providing a shell, wherein the shell is provided with a receiving space for receiving the electrode assembly; the shell comprises a first side plate located at one side along a first direction; A pressure relief mechanism providing device, used for providing a pressure relief mechanism, wherein the pressure relief mechanism is arranged on the first side plate; A cover assembly providing device, used for providing a cover assembly, wherein the cover assembly is used for sealing the housing; an assembling device for assembling the electrode assembly, the housing, the pressure relief mechanism and the cover assembly to form the battery cell; Wherein, a first flow channel extending along the inner surface is formed on the inner surface of the first side plate of the housing, and the first flow channel is used to guide the gas in the accommodating space to the pressure relief mechanism, so that the pressure relief mechanism is actuated and releases the pressure when the pressure reaches a threshold value; The first flow channel includes a plurality of first grooves disposed on and extending along the inner surface of the first side plate, one end of each of the first grooves being connected to the pressure relief mechanism, or, A protrusion protruding toward the accommodation space is formed on the inner surface of the first side plate, the protrusion has a top surface away from the inner surface, and the first flow channel is formed in a space between the top surface of the protrusion and the inner surface.

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