Battery cells, battery packs, and electrical devices

Abstract

This application discloses a battery cell, a battery device, and an electrical device. The battery cell includes a casing, electrode terminals, an electrode assembly, an adapter, and a pressure relief structure. The casing has a first wall, which includes a first recess and a flange. The first recess has a bottom wall and a side wall, and the flange is connected to the side wall. The electrode terminals are disposed on the bottom wall. The electrode assembly is disposed inside the casing and includes a main body and a tab. The tab faces the flange. There is a first gap between the main body and the bottom wall, and a second gap between the flange and the main body. The first gap is smaller than the second gap. The adapter is housed in the casing, and the tab and the electrode terminal are electrically connected through the adapter. The pressure relief structure is disposed on the bottom wall and is located on the side of the electrode terminal away from the tab. An exhaust channel is formed between the pressure relief structure and the main body. The adapter has a flow guiding structure that connects the space formed between the flange and the main body and the exhaust channel.

Description

Technical Field

[0001] This application relates to the field of batteries, and in particular to a battery cell, a battery device, and an electrical device. Background Technology

[0002] With the development of new energy technologies, batteries are being used more and more widely, for example in mobile phones, laptops, electric vehicles, electric cars, electric airplanes, electric ships, electric toy cars, electric toy ships, electric toy airplanes, and power tools.

[0003] The development of battery technology must take into account multiple design factors. For example, improving battery reliability is an important research direction in the battery field. Utility Model Content

[0004] This application provides a battery cell, a battery device, and an electrical device that can guide the hot airflow inside the battery cell to be discharged, thereby improving the heat dissipation performance of the battery cell and enhancing the reliability and safety of the battery.

[0005] In a first aspect, this application provides a battery cell, including a casing, electrode terminals, an electrode assembly, an adapter, and a pressure relief structure. The casing has a first wall, which includes a first recess and a flange. The first recess has a bottom wall and a side wall, and the flange is connected to the side wall. The electrode terminals are disposed on the bottom wall. The electrode assembly is disposed inside the casing and includes a main body and a tab. The tab is disposed facing the flange. There is a first distance between the main body and the bottom wall, and a second distance between the flange and the main body. The first distance is smaller than the second distance. The adapter is housed in the casing, and the tab and the electrode terminal are electrically connected through the adapter. The pressure relief structure is disposed on the bottom wall and is located on the side of the electrode terminal away from the tab. An exhaust channel is formed between the pressure relief structure and the main body. The adapter has a flow guiding structure that connects the space formed between the flange and the main body and the exhaust channel.

[0006] In this embodiment, the battery cell divides the first wall into a first recess and a flange, which correspond to the electrode terminals and tabs, respectively. The minimum distance between the first recess and the main body is less than the minimum distance between the flange and the main body, allowing the electrode terminals and tabs to share space in the height direction of the battery cell, thus reducing the size of the battery cell and increasing energy density. Simultaneously, to guide the hot airflow during battery cell use from the larger space between the flange and the main body to the smaller space between the first recess and the main body, a flow-guiding structure is provided in the adapter to guide the flow path of the hot airflow, accelerating the process of the hot airflow being discharged from the battery cell through the pressure relief structure, reducing heat accumulation inside the battery cell, and improving the safety of battery cell use.

[0007] In some alternative embodiments, the adapter includes a terminal connection portion and an electrode tab connection portion, at least a portion of the terminal connection portion being located between the bottom wall and the main body portion, the electrode terminal being connected to the terminal connection portion, the terminal connection portion including a flow guiding structure, the electrode tab connection portion being located between the flange and the main body portion, and the electrode tab being connected to the electrode tab connection portion.

[0008] In the above optional embodiments, the adapter connects the electrode terminal and the electrode tab respectively through the terminal connection part and the electrode tab connection part, thereby realizing the conductive connection between the electrode assembly and the electrode terminal. The flow guiding structure is opened in the terminal connection part between the electrode tab and the exhaust channel to shorten the path distance of the hot air around the electrode tab to flow to the pressure relief structure.

[0009] In some optional embodiments, the adapter further includes an inclined transition portion that connects the terminal connection portion and the tab connection portion, and the inclined transition portion is disposed corresponding to the side wall.

[0010] In the above optional embodiments, similar to the positions of the bottom wall and the flange, there is a height difference between the terminal connection portion and the tab connection portion and they are connected by an inclined transition portion. The inclined transition portion can be formed with a simpler processing technology to reduce the manufacturing cost of the battery cell.

[0011] In some optional embodiments, the vertical distance between the surface of the terminal connection portion near the main body and the surface of the tab connection portion near the main body is greater than 0 mm and less than or equal to 2 mm.

[0012] In the above optional embodiments, after the electrode connection part establishes a conductive connection with the electrode, a gap other than the flow guiding structure is formed between the terminal connection part and the main body part, which accelerates the flow of hot air around the electrode to the pressure relief structure.

[0013] In some alternative embodiments, the flow guiding structure includes a guide groove, which is provided on the surface of the terminal connection portion facing the main body portion.

[0014] In the above optional embodiments, the guide groove can establish a path between the space formed between the bottom wall and the main body and between the exhaust channel to allow the hot airflow to flow smoothly. The guide groove is set on the surface to facilitate the processing and forming of the flow guiding structure.

[0015] In some optional embodiments, there are two or more guide slots, which are spaced apart along the thickness direction of the battery cell.

[0016] In the above optional embodiments, multiple guide slots can divert hot airflow and accelerate the flow of hot airflow toward the pressure relief structure.

[0017] In some alternative embodiments, the guide groove is a straight groove.

[0018] In the above optional embodiments, the processing difficulty of the guide groove is reduced, and the flow path of the hot air is shortened, so that the hot air flows to the pressure relief structure more quickly.

[0019] In some optional embodiments, along the thickness direction of the battery cell, the total width of all guide grooves is W1, and the total width of the terminal connection is W2. W1 and W2 satisfy the relationship: 1 / 4≤W1 / W2≤1 / 2.

[0020] In the above optional embodiments, the guide groove has a better flow guiding effect, while reducing the damage to the structural strength of the terminal connection part caused by opening the guide groove.

[0021] In some optional embodiments, the depth of the guide groove is H1, and the thickness of the terminal connection is H2, wherein H1 and H2 satisfy the relationship: 1 / 4≤H1 / H2≤1 / 2.

[0022] In the above optional embodiments, the cross-sectional area of ​​the guide groove is increased to improve the airflow, while the terminal connection has better flow capacity.

[0023] In some optional embodiments, a second recess is provided on the surface of the terminal connection portion facing the main body portion, at least a portion of the guide grooves communicate with the second recess, and the area on the terminal connection portion corresponding to the second recess is welded to the electrode terminal.

[0024] In the above optional embodiments, the electrode terminals are welded to the adapter through the area corresponding to the second recess.

[0025] In some alternative embodiments, the bottom surface of the second recess is provided with a plurality of third recesses.

[0026] In the above optional embodiments, the surface area of ​​the terminal connection portion is increased to improve the current carrying capacity of the terminal connection portion.

[0027] Secondly, this application provides a battery device, which includes the battery cell provided in any embodiment of the first aspect.

[0028] Thirdly, this application provides an electrical device, which includes the battery device provided in any embodiment of the second aspect, and the battery device is used to provide electrical energy. Attached Figure Description

[0029] The features, advantages, and technical effects of exemplary embodiments of this application will now be described with reference to the accompanying drawings.

[0030] Figure 1 This is a schematic diagram of the structure of an electrical device according to an embodiment of this application;

[0031] Figure 2 This is a schematic diagram of the structure of a battery device according to an embodiment of this application;

[0032] Figure 3 This is a schematic diagram of the structure of a battery cell pack according to an embodiment of this application;

[0033] Figure 4 This is a three-dimensional structural diagram of a battery cell according to an embodiment of this application;

[0034] Figure 5 for Figure 4 A schematic diagram of the cross-sectional structure of a single battery cell is shown.

[0035] Figure 6 for Figure 5 Enlarged structural diagram at point A;

[0036] Figure 7 This is a schematic diagram of the structure of an adapter according to an embodiment of this application;

[0037] Figure 8 for Figure 7 A schematic diagram of the adapter from another perspective.

[0038] The accompanying drawings are not necessarily drawn to scale.

[0039] The specific marking information in the attached diagram is as follows:

[0040] 1000, vehicles;

[0041] 100. Battery assembly; 200. Controller; 300. Motor;

[0042] 10. Box body; 11. First box body section; 12. Second box body section;

[0043] 20. Battery cell pack; 21. Battery cell;

[0044] 211. Outer shell; 2111. First wall; 21111. Bottom wall; 21112. Side wall; 21113. Flanged edge; 2112. Mounting cavity; 212. Electrode assembly; 2121. Main body; 2122. Electrode tab; 213. Electrode terminal; 214. Adapter; 2141. Electrode tab connection; 2142. Terminal connection; 21421. Guide groove; 21422. Second recess; 21423. Third recess; 2143. Inclined transition section; 215. Pressure relief structure; 2151. Exhaust passage;

[0045] Battery cell width direction X; battery cell thickness direction Y; battery cell height direction Z. Detailed Implementation

[0046] The embodiments of the technical solution of this application will now be described in detail with reference to the accompanying drawings. These embodiments are only used to more clearly illustrate the technical solution of this application and are therefore merely examples, and should not be used to limit the scope of protection of this application.

[0047] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application pertains; the terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the application; the terms “comprising” and “having”, and any variations thereof, in the specification, claims, and foregoing description of the drawings are intended to cover non-exclusive inclusion.

[0048] In the description of the embodiments of this application, technical terms such as "first" and "second" are used only to distinguish different objects and should not be construed as indicating or implying relative importance or implicitly specifying the number, specific order, or primary and secondary relationship of the indicated technical features. In the description of the embodiments of this application, "multiple" means two or more, unless otherwise explicitly defined.

[0049] In this document, the term "embodiment" means that a particular feature, structure, or characteristic described in connection with an embodiment may be included in at least one embodiment of this application. The appearance of this phrase in various places throughout the specification does not necessarily refer to the same embodiment, nor is it a separate or alternative embodiment mutually exclusive with other embodiments. It will be explicitly and implicitly understood by those skilled in the art that the embodiments described herein can be combined with other embodiments.

[0050] In the description of the embodiments in this application, the term "and / or" is merely a description of the relationship between related objects, indicating that three relationships can exist. For example, A and / or B can represent: A existing alone, A and B existing simultaneously, and B existing alone. Additionally, the character " / " in this document generally indicates that the preceding and following related objects have an "or" relationship.

[0051] In the description of the embodiments of this application, the term "multiple" refers to two or more (including two), similarly, "multiple sets" refers to two or more (including two sets), and "multiple pieces" refers to two or more (including two pieces).

[0052] In the description of the embodiments of this application, the technical terms "center," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," "counterclockwise," "axial," "radial," and "circumferential" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing the embodiments of this application and simplifying the description, and are not intended to indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on the embodiments of this application.

[0053] In the description of the embodiments of this application, unless otherwise expressly specified and limited, technical terms such as "installation," "connection," "joining," and "fixing" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components. For those skilled in the art, the specific meaning of the above terms in the embodiments of this application can be understood according to the specific circumstances.

[0054] Currently, judging from market trends, the application of power batteries is becoming increasingly widespread. Power batteries are not only used in energy storage systems such as hydropower, thermal power, wind power, and solar power plants, but also extensively used in electric vehicles such as electric bicycles, electric motorcycles, and electric cars, as well as in military equipment and aerospace. With the continuous expansion of power battery applications, market demand is also constantly increasing.

[0055] As a core component of power batteries, the safety of individual battery cells is a major concern. With continuous advancements in battery technology, while the energy density of individual cells has significantly increased, the rate of internal heat generation has also accelerated. Furthermore, with the increasing integration of individual battery cells, the problem of insufficient heat dissipation space has emerged within them, further hindering the release of internal heat. On the one hand, heat accumulation inside the battery cell shortens the lifespan of internal components such as electrodes and affects performance; on the other hand, excessively high temperatures may trigger the melting of internal components and lead to a chain reaction of thermal runaway.

[0056] To address the aforementioned issues, the applicant proposes a battery cell that, while increasing the integration density of the battery cell, constructs heat dissipation channels within the battery cell through reasonable arrangement to guide the flow of hot air, thereby accelerating the release of heat inside the battery cell, reducing the probability of thermal runaway, and improving the reliability of the battery cell.

[0057] In this embodiment of the application, the battery cell can be a secondary battery, which refers to a battery cell that can be recharged to activate the active materials and continue to be used after the battery cell has been discharged.

[0058] The battery cell can be a lithium-ion battery, sodium-ion battery, sodium-lithium-ion battery, lithium metal battery, sodium metal battery, lithium-sulfur battery, magnesium-ion battery, nickel-metal hydride battery, nickel-cadmium battery, lead-acid battery, etc., and the embodiments of this application are not limited to this.

[0059] As an example, the battery cell can be a cylindrical battery cell, a prismatic battery cell, a pouch battery cell, or a battery cell of other shapes. Prismatic battery cells include prismatic battery cells, blade-shaped battery cells, and multi-prismatic batteries, such as hexagonal prismatic batteries. This application does not have any particular limitations.

[0060] In some embodiments, the battery cell may include a casing. The casing may be a steel casing, an aluminum casing, a plastic casing (such as a polypropylene casing), a composite metal casing (such as a copper-aluminum composite casing), or an aluminum-plastic film, etc. In some embodiments, the casing may be a sealed structure or a non-sealed structure. As an example, when the casing is a non-sealed structure, the casing serves to protect the electrode assembly, and a sealing bag is included between the casing and the electrode assembly to encapsulate the electrode assembly and electrolyte. Specifically, the sealing bag may be a bag-shaped insulating component or an aluminum-plastic film. When the casing is a sealed structure, it is used to encapsulate components such as the electrode assembly and electrolyte.

[0061] In some embodiments, the housing includes an end cap and a housing, the housing having an opening, and the end cap covering the opening. The housing may have one or more openings. The end cap may also have one or more.

[0062] The solutions in this application can be applied to, but are not limited to, individual battery cells, as well as to battery devices including individual battery cells and electrical devices including individual battery cells and battery devices.

[0063] This application provides an electrical device that uses a battery as a power source. The electrical device can be, but is not limited to, mobile phones, tablets, laptops, electric toys, power tools, electric vehicles, electric cars, ships, spacecraft, etc. Among them, electric toys can include stationary or mobile electric toys, such as game consoles, electric car toys, electric ship toys, and electric airplane toys, etc., and spacecraft can include airplanes, rockets, space shuttles, and spacecraft, etc.

[0064] For ease of explanation, the following embodiments will be described using a vehicle 1000 as an example of an electrical device according to an embodiment of this application.

[0065] Please see Figure 1 , Figure 1This is a schematic diagram of the structure of a vehicle 1000 provided in some embodiments of this application. The vehicle 1000 can be a gasoline-powered vehicle, a natural gas-powered vehicle, or a new energy vehicle. New energy vehicles can be pure electric vehicles, hybrid electric vehicles, or range-extended electric vehicles, etc. A battery device 100 is provided inside the vehicle 1000, and the battery device 100 can be located at the bottom, front, or rear of the vehicle 1000. The battery device 100 can be used to power the vehicle 1000; for example, the battery device 100 can serve as the operating power source for the vehicle 1000. The vehicle 1000 may also include a controller 200 and a motor 300. The controller 200 is used to control the battery device 100 to supply power to the motor 300, for example, to meet the power needs of the vehicle 1000 during starting, navigation, and driving.

[0066] In some embodiments of this application, the battery device 100 can not only serve as the operating power source for the vehicle 1000, but also as the driving power source for the vehicle 1000, replacing or partially replacing fuel or natural gas to provide driving power for the vehicle 1000.

[0067] The battery device 100 mentioned in the embodiments of this application may include one or more battery cell groups 20 for providing voltage and capacity. A battery cell group may include multiple battery cells, which are connected in series, parallel, or mixed connections via a busbar.

[0068] In some embodiments, a battery cell group is typically formed by arranging multiple battery cells; as an example, a battery cell group can be a battery module, which is formed by arranging and fixing multiple battery cells into an independent module. As an example, a battery module can be formed by bundling multiple battery cells together with cable ties.

[0069] In some embodiments, the battery device 100 may be a battery pack, which includes a housing and one or more battery cell groups 20 housed in the housing.

[0070] Please see Figure 2 , Figure 2 This is an exploded structural diagram of a battery device 100 provided in some embodiments of this application. The battery device 100 includes a housing 10 and a battery cell pack 20, the battery cell pack 20 being housed within the housing 10.

[0071] The housing 10 is used to accommodate individual battery cells, and the housing 10 can have various structures. In some embodiments, the housing 10 may include a first housing portion 11 and a second housing portion 12, which overlap each other, and together define a receiving portion for accommodating the battery cell assembly 20. The second housing portion 12 may be a hollow structure with one end open, and the first housing portion 11 may be a plate-like structure, with the first housing portion 11 covering the open side of the second housing portion 12 to form a housing 10 with a receiving portion; alternatively, both the first housing portion 11 and the second housing portion 12 may be hollow structures with one side open, with the open side of the first housing portion 11 covering the open side of the second housing portion 12 to form a housing 10 with a receiving portion. Of course, the first housing portion 11 and the second housing portion 12 can have various shapes, such as cylinders, cuboids, etc.

[0072] As an example, the battery cell pack 20 can be a battery module, which can be housed in the housing by fixing the battery module in the housing.

[0073] As an example, the battery cell pack 20 can also be housed in the housing by directly fixing multiple battery cells to the housing.

[0074] In some embodiments, the housing may be part of the chassis structure of the vehicle 1000. For example, a portion of the housing may be at least a portion of the floor of the vehicle 1000, or a portion of the housing may be at least a portion of the crossbeams and longitudinal beams of the vehicle 1000.

[0075] In some embodiments, the battery device 100 may be an energy storage device. Energy storage devices include energy storage containers, energy storage cabinets, etc.

[0076] Please see Figure 3 , Figure 3 This is a schematic diagram of the structure of a battery cell pack 20 provided in an embodiment of this application. The battery cell pack 20 includes multiple battery cells 21, which are first connected in series, parallel, or mixed to form the battery cell pack 20, and then the battery cell pack 20 is housed in a casing.

[0077] The following describes the battery cell provided in the embodiments of this application. Please refer to [link / reference]. Figures 4 to 8 , Figure 4 This is a three-dimensional structural diagram of a battery cell according to an embodiment of this application; Figure 5 for Figure 4 A schematic diagram of the cross-sectional structure of a single battery cell is shown. Figure 6 for Figure 5 Enlarged structural diagram at point A;

[0078] Figure 7 This is a schematic diagram of the structure of an adapter according to an embodiment of this application; Figure 8 for Figure 7 A schematic diagram of the adapter from another perspective.

[0079] In a first aspect, embodiments of this application provide a battery cell, which includes a housing 211, electrode terminals 213, electrode assemblies 212, and an adapter 214. The housing 211 has a first wall 2111, which includes a first recess and a flange 21113. The first recess has a bottom wall 21111 and a side wall 21112, and the flange 21113 is connected to the side wall 21112. The electrode terminals 213 are disposed on the bottom wall 21111. The electrode assembly 214... 12 is disposed inside the housing 211. The electrode assembly 212 includes a main body 2121 and a tab 2122. The tab 2122 is disposed toward the flange 21113. There is a first gap between the main body 2121 and the bottom wall 21111, and a second gap between the flange 21113 and the main body 2121. The first gap is smaller than the second gap. The adapter 214 is housed in the housing 211. The tab 2122 and the electrode terminal 213 are electrically connected through the adapter 214.

[0080] Therefore, the distance between the flange 21113 and the main body 2121 is smaller than the distance between the bottom wall 21111 and the main body 2121, so that the tab 2122 provided between the flange 21113 and the main body 2121 can share part of the space with the electrode terminal 213 connected to the bottom wall 21111 in the height direction of the battery cell, which helps to reduce the size of the battery cell in the height direction, thereby improving the integration and energy density.

[0081] The battery cell in this embodiment also includes a pressure relief structure 215, which is disposed on the bottom wall 21111 and located on the side of the electrode terminal 213 away from the tab 2122. An exhaust channel 2151 is formed between the pressure relief structure 215 and the main body 2121. It is understood that the hot airflow generated in the area around the tab 2122 needs to pass through the distance between the bottom wall 21111 and the main body 2121 when flowing to the pressure relief structure 215. However, since the space between the bottom wall 21111 and the main body 2121 is small, the hot airflow is relatively slow and obstructed when flowing to the pressure relief structure 215, which causes heat to easily accumulate in the area around the tab 2122, creating local hot spots. In this embodiment, a flow guiding structure is provided on the adapter 214. The flow guiding structure can connect the space formed between the flange 21113 and the main body 2121 and the exhaust channel 2151. The flow guiding structure can form a flow channel between the area around the tab 2122 and the exhaust channel 2151 to guide the hot air flow to the pressure relief structure 215 and discharge it from the battery cell, thereby reducing the heat accumulation inside the battery cell and improving the heat dissipation performance and safety of the battery cell.

[0082] It can be understood that the pressure relief structure 215 refers to a component or part that is actuated to release internal pressure or temperature when the internal pressure or temperature of a battery cell reaches a predetermined threshold. This threshold design varies depending on design requirements and may depend on one or more materials among the positive electrode, negative electrode, electrolyte, and separator in the battery cell. The pressure relief structure 215 can take the form of an explosion-proof valve, gas valve, pressure relief valve, or safety valve, and can specifically employ a pressure-sensitive element or structure. That is, when the internal pressure of the battery cell reaches the predetermined threshold, the pressure relief structure 215 actuates or a weak point in the pressure relief structure 215 ruptures, thereby forming an opening or channel for internal pressure release. The weak point can be formed by setting grooves, indentations, or using materials with lower strength.

[0083] Therefore, the battery cell provided in this application embodiment can reduce the negative impact of this structural design on the internal heat dissipation of the battery cell while improving integration and energy density. The battery cell has both good economic benefits and high safety performance.

[0084] According to some embodiments of this application, the adapter 214 includes a terminal connection portion 2142 and an electrode connection portion 2141. At least a portion of the terminal connection portion 2142 is located between the bottom wall 21111 and the main body portion 2121. The electrode terminal 213 is connected to the terminal connection portion 2142. The terminal connection portion 2142 includes a flow guiding structure. The electrode connection portion 2141 is located between the flange 21113 and the main body portion 2121. The electrode 2122 is connected to the electrode connection portion 2141.

[0085] Optionally, please refer to Figure 5 or Figure 6 An installation cavity 2112 is formed between the tab connection portion 2141, the main body portion 2121, and the outer casing 211, and the tab 2122 is accommodated in the installation cavity 2112. The installation cavity 2112 is connected to the exhaust channel 2151 at least through a flow guiding structure so that the hot air flow in the installation cavity 2112 can be discharged from the battery cell through the pressure relief structure 215.

[0086] Optionally, along the height direction of the battery cell, the tab connection portion 2141 and the terminal connection portion 2142 are at least partially overlapped to shorten the current path between the electrode assembly 212 and the electrode terminal 213. For example, the upper surface of the terminal connection portion 2142 is flush with the upper surface of the tab connection portion 2141, or the upper surface of the terminal connection portion 2142 is flush with the lower surface of the tab connection portion 2141, or the upper surface of the terminal connection portion 2142 is located between the upper and lower surfaces of the tab connection portion 2141.

[0087] Optionally, the tab connection portion 2141 is disposed between the main body portion 2121 and the tab 2122, and there is an insulating gap between the tab connection portion 2141 and the main body portion 2121, for example, separated by a blue film or other insulating material.

[0088] Thus, the electrode terminal 213 and the tab 2122 are electrically connected through the terminal connection portion 2142 and the tab connection portion 2141. The flow guiding structure is opened in the terminal connection portion 2142 located between the tab 2122 and the exhaust channel 2151 to shorten the path distance of the hot air flow in the area around the tab 2122 to the exhaust channel 2151 and the pressure relief structure 215, thereby accelerating the dissipation of the hot air flow.

[0089] According to some embodiments of this application, the adapter 214 further includes an inclined transition portion 2143, which connects the terminal connection portion 2142 and the tab connection portion 2141. The inclined transition portion 2143 is correspondingly disposed with respect to the side wall 21112. It can be understood that, along the width direction of the battery cell, the terminal connection portion 2142 and the tab connection portion 2141 are respectively disposed on both sides of the inclined transition portion 2143.

[0090] Optionally, in some embodiments, the orthographic projection of the tab connection portion 2141 on the main body portion 2121 and the orthographic projection of the terminal connection portion 2142 on the main body portion 2121 are arranged adjacent to or spaced apart, so as to facilitate the assembly of the adapter 214 with the tab 2122 and the electrode terminal 213.

[0091] Alternatively, in other embodiments, the orthographic projection of the tab connection portion 2141 on the main body portion 2121 and the orthographic projection of the terminal connection portion 2142 on the main body portion 2121 partially overlap, and the tab connection portion 2141 and the terminal connection portion 2142 share a portion of the space in the width direction of the battery cell, so as to reduce the size of the battery cell in the width direction.

[0092] Therefore, the tab connection portion 2141, the inclined transition portion 2143, and the terminal connection portion 2142 are sequentially provided corresponding to the flange 21113, the side wall 21112, and the bottom wall 21111, so that the adapter 214 has a structure similar to the first wall 2111, improving the compactness of the internal structure design of the battery cell and further increasing the energy density of the battery cell. Furthermore, when there is a height difference between the tab connection portion 2141 and the terminal connection portion 2142, the inclined transition portion 2143 can be formed using a simpler processing technology compared to other transition structures, helping to reduce the manufacturing cost of the adapter 214 and the battery cell.

[0093] According to some other embodiments of this application, the adapter 214 includes a vertical transition portion, which is correspondingly disposed with the flange 21113, and the vertical transition portion is used to adapt to the height difference between the tab connection portion 2141 and the terminal connection portion 2142.

[0094] According to some embodiments of this application, the vertical distance between the surface of the terminal connection portion 2142 near the main body portion 2121 and the surface of the tab connection portion 2141 near the main body portion 2121 does not exceed the thickness of the tab 2122.

[0095] Optionally, please refer to Figure 6 The vertical distance between the surface of the terminal connection portion 2142 near the main body portion 2121 and the surface of the tab connection portion 2141 near the main body portion 2121 is defined as m, where m is greater than 0 mm and less than or equal to 2 mm. For example, m is one of 0.25 mm, 0.5 mm, 0.75 mm, 1 mm, 1.25 mm, 1.5 mm, 1.75 mm, and 2 mm.

[0096] As a result, a gap other than the flow guiding structure is formed between the terminal connection part 2142 and the main body part 2121, allowing the hot airflow to flow between the mounting cavity 2112 and the exhaust channel 2151, accelerating the process of the hot airflow inside the battery cell being discharged to the pressure relief structure 215.

[0097] According to some embodiments of this application, the flow guiding structure includes a guide groove 21421.

[0098] Optionally, the guide groove 21421 is formed on the surface of the terminal connection portion 2142 facing the main body portion 2121 to facilitate the processing of the guide groove 21421.

[0099] Optionally, the guide groove 21421 is formed inside the terminal connection portion 2142. For example, the guide groove 21421 is a hollow cavity extending along the width direction of the battery cell. The axial direction of the hollow cavity is parallel to the width direction of the battery cell, or the axial direction of the hollow cavity is at an acute angle to the width direction of the battery cell.

[0100] It is understood that the guide groove 21421 provided on the surface of the terminal connection portion 2142 and the hollow tube-shaped guide groove 21421 can be provided separately or in combination.

[0101] Thus, the opening of the guide groove 21421 can establish a path between the space between the bottom wall 21111 and the main body 2121 and the exhaust channel 2151 and increase the cross-sectional area of ​​the flow channel to expand the flow rate of hot air, thereby accelerating the flow of hot air in the area around the tab 2122 to the exhaust channel 2151 and the pressure relief structure 215.

[0102] According to some embodiments of this application, the number of guide grooves 21421 is two or more, and the two or more guide grooves 21421 are spaced apart along the thickness direction of the battery cell.

[0103] Optionally, the depth of each guide groove 21421 is set to be the same so that the guide groove 21421 can be formed with as few process steps as possible, thereby reducing the processing cost of the guide structure.

[0104] Optionally, the depths of two or more guide grooves 21421 may be differentiated. For example, along the thickness direction of the battery cell, the depth of the guide groove 21421 located in the middle is greater than the depth of the guide grooves 21421 located on both sides, or the depth of the guide groove 21421 located in the middle is less than the depth of the guide grooves 21421 located on both sides, to adjust the guiding effect of the flow guiding structure on the hot airflow. It is understood that in some embodiments, the depths of each guide groove 21421 are differentiated, or some guide grooves 21421 have the same depth, while the depths of the remaining guide grooves 21421 are at least differentiated from the depths of the preceding guide grooves 21421.

[0105] Therefore, two or more guide slots 21421 can divert the hot airflow and accelerate the flow of hot airflow to the exhaust channel 2151 and the pressure relief structure 215.

[0106] According to some embodiments of this application, the guide groove 21421 is a straight groove to reduce the accumulation of hot air in the guide groove 21421 and shorten the flow path, thereby accelerating the discharge of hot air to the pressure relief structure 215.

[0107] Optionally, the extension direction of the guide groove 21421 is set parallel to the width direction of the battery cell.

[0108] Optionally, the extension direction of the guide groove 21421 is set at an acute angle to the width direction of the battery cell. The extension direction of the guide groove 21421 is inclined towards at least one of the thickness direction and the height direction of the battery cell.

[0109] According to some other embodiments of this application, the guide groove 21421 includes at least one curved surface structure. The curved surface structure can increase the contact area between the hot airflow and the guide groove 21421 and prolong the residence time of the hot airflow in the guide groove 21421. The hot airflow can complete a small amount of heat exchange with the terminal connection 2142. For example, when the temperature of the hot airflow is lower than the temperature of the terminal connection 2142, the process of the hot airflow being discharged to the pressure relief structure 215 can have a cooling effect on the adapter 214.

[0110] According to some embodiments of this application, along the thickness direction of the battery cell, the total width of all guide grooves 21421 is W1, and the total width of the terminal connection portion 2142 is W2. W1 is at least 1 / 4 times W2, so that the flow guiding structure can form a more significant guiding flow effect on the hot airflow and achieve improved heat dissipation performance.

[0111] According to some embodiments of this application, along the thickness direction of the battery cell, the total width of all guide grooves 21421 is W1, and the total width of the terminal connection portion 2142 is W2. W1 is at most 1 / 2 times W2, so as to reduce the damage to the structural strength of the terminal connection portion 2142 caused by the opening of the flow guiding structure.

[0112] According to some embodiments of this application, along the height direction of the battery cell, the total width of all guide grooves 21421 is H1, and the total width of the terminal connection portion 2142 is H2. H1 is at least 1 / 4 times H2, so that the flow guiding structure can significantly increase the flow rate of hot air and improve the heat dissipation performance.

[0113] According to some embodiments of this application, along the height direction of the battery cell, the total width of all guide grooves 21421 is H1, and the total width of the terminal connection portion 2142 is H2. H1 is at most 1 / 2 times H2, so as to reduce the loss of the current carrying capacity of the terminal connection portion 2142 due to the opening of the current guiding structure.

[0114] According to some embodiments of this application, a buffer structure is formed between the guide groove 21421 and the surface of the terminal connection portion 2142 facing the main body portion 2121. The buffer structure can increase the cross-sectional area of ​​the flow channel of the guide structure and form a buffer effect on the airflow at the inlet of the guide structure.

[0115] Optionally, the buffer structure is configured as a chamfered surface, with the two ends of the chamfered surface connected to the groove wall of the guide groove 21421 and the surface of the terminal connection part 2142 facing the main body part 2121, respectively.

[0116] Optionally, the buffer structure is configured as a rounded surface, with the two ends of the rounded surface connected to the groove wall of the guide groove 21421 and the surface of the terminal connection portion 2142 facing the main body portion 2121, respectively.

[0117] According to some embodiments of this application, a second recess 21422 is provided on the surface of the terminal connection portion 2142 facing the main body portion 2121, and the area on the terminal connection portion 2142 corresponding to the second recess 21422 is welded to the electrode terminal 213.

[0118] It is understood that the area on the terminal connection portion 2142 corresponding to the second recess 21422 refers to the area located on the surface of the terminal connection portion 2142 facing away from the main body portion 2121, and whose orthogonal projection on the main body portion 2121 at least partially overlaps with the orthogonal projection of the second recess 21422 on the main body portion 2121.

[0119] Optionally, at least a portion of the guide grooves 21421 are connected to the second recess 21422 to reduce the connection between the processing of the second recess 21422 and the processing of the guide grooves 21421, thereby facilitating the forming of the adapter 214.

[0120] Optionally, each guide groove 21421 is disposed in a manner that avoids the second recess 21422, so as to reduce the occurrence of hot airflow flowing into the second recess 21422 through the guide groove 21421 and causing heat accumulation in the second recess 21422.

[0121] Therefore, when the electrode terminal 213 is welded to the terminal connection portion 2142, the second recess 21422 can accommodate the solder mark between the terminal connection portion 2142 and the electrode terminal 213, reducing the risk of the solder mark damaging the electrode assembly 212 and the space occupied by the solder mark in the height direction of the battery cell, thereby improving the energy density of the battery cell's reliability.

[0122] According to some embodiments of this application, the bottom surface of the second recess 21422 is provided with a plurality of third recesses 21423.

[0123] Optionally, a plurality of third recesses 21423 are arranged in an array on the second recess 21422. For example, the plurality of third recesses 21423 are arranged in a rectangular array, or the plurality of third recesses 21423 are arranged in a circular array.

[0124] Optionally, multiple third recesses 21423 are formed simultaneously with the second recesses 21422 by a stamping process.

[0125] Thus, the combination of the third recess 21423 and the second recess 21422 improves the structural strength of the adapter 214. At the same time, the third recess 21423 can increase the surface area of ​​the second recess 21422 to improve the flow capacity of the adapter 214.

[0126] Secondly, embodiments of this application provide a battery device 100, which includes a battery cell provided in any embodiment of the first aspect, and the battery cell is provided with at least one. It is understood that the battery device 100 possesses all the beneficial effects of the battery cell provided in any embodiment of the first aspect.

[0127] Thirdly, embodiments of this application provide an electrical device that includes the battery device 100 provided in any embodiment of the second aspect, wherein the battery device 100 is used to provide electrical energy. It is understood that the electrical device indirectly includes the battery cell provided in any embodiment of the first aspect, and therefore also has all the beneficial effects of the battery cell provided in any embodiment of the first aspect.

[0128] Please see Figures 4 to 8 This application provides a battery cell, which includes a housing 211, an electrode assembly 212, an electrode terminal 213, and an adapter 214. The housing 211 includes a first wall 2111, which includes a first recess and a flange 21113. The first recess includes a side wall 21112 connected to the flange 21113 and a bottom wall 21111 connected to the electrode terminal 213. The electrode assembly 212 includes a main body 2121 and a tab 2122 extending from the main body 2121. The tab 2122 is disposed between the flange 21113 and the main body 2121, and is electrically connected to the electrode terminal 213 through the adapter 214. The distance between the bottom wall 21111 of the first recess and the main body 2121 is smaller than the distance between the flange 21113 and the main body 2121, so that the electrode terminal 213 and the tab 2122 can share part of the space in the height direction of the battery cell.

[0129] The battery cell also includes a pressure relief structure 215, which is located on the side of the electrode terminal 213 away from the tab 2122 and forms an exhaust channel 2151 between it and the main body 2121. The adapter 214 has a flow guiding structure to connect the space formed between the flange 21113 and the main body 2121 and the exhaust channel 2151. The flow guiding structure can guide the hot air flow inside the battery cell to the exhaust channel 2151 and the pressure relief structure 215.

[0130] The adapter 214 includes a tab connection portion 2141, an inclined transition portion 2143, and a terminal connection portion 2142 arranged sequentially along the width direction of the battery cell. The bottom surface of the tab connection portion 2141 is connected to the tab 2122, and the top surface of the terminal connection portion 2142 is connected to the electrode terminal 213. The bottom surface of the terminal connection portion 2142 is spaced apart from the main body portion 2121 and has a flow guiding structure. Hot airflow can pass through the flow guiding structure and the gap between the terminal connection portion 2142 and the main body portion 2121 to the exhaust channel 2151 and the pressure relief structure 215.

[0131] The flow guiding structure includes multiple parallel guide grooves 21421 with the same depth. The multiple guide grooves 21421 are equally spaced on the bottom surface of the terminal connection part 2142. The multiple guide grooves 21421 can divert the hot airflow to accelerate the flow and reduce accumulation.

[0132] The bottom surface of the terminal connection portion 2142 is further provided with a second recess 21422, and a third recess 21423 is further provided at the bottom of the groove of the second recess 21422. The second recess 21422 is provided in the form of a circular groove, and the third recesses 21423 are distributed in a circular array at the bottom of the groove of the second recess 21422. The provision of the second recess 21422 and the third recess 21423 can strengthen the welding connection between the electrode terminal 213 and the terminal connection portion 2142.

[0133] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of this application, and not to limit them. Although this application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features therein. These modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of this application, and they should all be covered within the scope of the claims and specification of this application. In particular, as long as there is no structural conflict, the various technical features mentioned in the embodiments can be combined in any way. This application is not limited to the specific embodiments disclosed herein, but includes all technical solutions falling within the scope of the claims.

Claims

1. A battery cell, characterized in that, include: The outer casing has a first wall, the first wall including a first recess and a flange, the first recess having a bottom wall and a side wall, and the flange being connected to the side wall; Electrode terminals are disposed on the bottom wall; An electrode assembly is disposed within the housing. The electrode assembly includes a main body and an electrode tab. The electrode tab is disposed facing the flange. The main body has a first distance from the bottom wall, and the flange has a second distance from the main body. The first distance is smaller than the second distance. An adapter is housed in the housing, and the tabs and electrode terminals are electrically connected through the adapter; A pressure relief structure is provided on the bottom wall, the pressure relief structure is located on the side of the electrode terminal away from the electrode tab, and an exhaust channel is formed between the pressure relief structure and the main body; The adapter is provided with a flow guiding structure, which connects the space formed between the flange and the main body and the exhaust channel.

2. The battery cell according to claim 1, characterized in that, The adapter includes a terminal connection portion and an electrode tab connection portion. At least a portion of the terminal connection portion is located between the bottom wall and the main body portion. The electrode terminal is connected to the terminal connection portion. The terminal connection portion includes a flow guiding structure. The electrode tab connection portion is located between the flange and the main body portion. The electrode tab is connected to the electrode tab connection portion.

3. The battery cell according to claim 2, characterized in that, The adapter includes an inclined transition portion that connects the terminal connection portion and the tab connection portion, and the inclined transition portion is disposed corresponding to the side wall.

4. The battery cell according to claim 3, characterized in that, The vertical distance between the surface of the terminal connection portion near the main body and the surface of the tab connection portion near the main body is greater than 0 mm and less than or equal to 2 mm.

5. The battery cell according to claim 2, characterized in that, The flow guiding structure includes a guide groove, and the guide groove is provided on the surface of the terminal connection portion facing the main body portion.

6. The battery cell according to claim 5, characterized in that, The number of guide grooves is two or more, and the two or more guide grooves are spaced apart along the thickness direction of the battery cell.

7. The battery cell according to claim 5 or 6, characterized in that, The guide groove is a straight groove.

8. The battery cell according to claim 5 or 6, characterized in that, Along the thickness direction of the battery cell, the total width of all the guide grooves is W1, and the total width of the terminal connection is W2. W1 and W2 satisfy the relationship: 1 / 4≤W1 / W2≤1 / 2.

9. The battery cell according to claim 5 or 6, characterized in that, The depth of the guide groove is H1, and the thickness of the terminal connection is H2. H1 and H2 satisfy the relationship: 1 / 4≤H1 / H2≤1 / 2.

10. The battery cell according to claim 6, characterized in that, The terminal connection portion has a second recess on the surface facing the main body portion, at least a portion of the guide grooves communicate with the second recess, and the area on the terminal connection portion corresponding to the second recess is welded to the electrode terminal.

11. The battery cell according to claim 10, characterized in that, The bottom surface of the second recess is provided with multiple third recesses.

12. A battery device, characterized in that, Includes the battery cell as described in any one of claims 1 to 11.

13. An electrical appliance, characterized in that, Includes the battery device as described in claim 12, the battery device being used to provide electrical energy.

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