Battery monomer, battery and electric device

Abstract

The utility model provides a battery monomer, a battery and a power utilization device, and belongs to the field of batteries. The battery monomer comprises a shell, an electrode assembly, a current collecting component and a pressure relief part; the shell comprises a containing cavity, the electrode assembly is located in the containing cavity, the electrode assembly comprises a main body part and a tab protruding out of the main body part, and the main body part is provided with a center hole extending in the height direction of the battery single body and penetrating through the electrode assembly; the current collecting component is positioned in the accommodating cavity and is electrically connected with the tabs; the pressure relief component is connected with the shell, and one side, facing the electrode assembly, of the pressure relief component is in fluid communication with the central hole; the current collecting member includes at least one fluid channel configured to fluidly communicate a gap between the electrode assembly and the housing and the central bore. By arranging the fluid channel in the current collecting component, a guiding effect can be provided for gas flow in the battery monomer, so that gas can be guided to the position where the pressure relief component is located, and smooth exhaust is realized.

Description

Technical Field

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

[0002] Energy conservation and emission reduction are the key to the sustainable development of the automobile industry. Electric vehicles have become an important part of the sustainable development of the automobile industry due to their advantages in energy conservation and environmental protection. For electric vehicles, battery technology is an important factor in their development.

[0003] During the charge and discharge process of the battery cell, the electrode assembly will generate gas, which will accumulate inside the battery cell, causing the pressure inside the battery cell to gradually increase, thus affecting the safety performance of the battery. Therefore, it is necessary to discharge the gas from a designated location when the gas pressure inside the battery cell reaches a certain pressure. However, the compact internal structure of the battery cell will hinder the flow of gas to a certain extent, resulting in poor exhaust or inability to exhaust in a directional manner. Utility Model Content

[0004] The present application aims to solve at least one of the technical problems existing in the background technology. To this end, one purpose of the present application is to provide a battery cell, a battery and an electrical device to improve the problem of poor exhaust of the battery cell.

[0005] An embodiment of the first aspect of the present application provides a battery cell, comprising a shell, an electrode assembly, a current collecting component and a pressure relief component; the shell comprises a accommodating cavity, the electrode assembly is located in the accommodating cavity, the electrode assembly comprises a main body and a pole ear protruding from the main body, the main body has a central hole extending along the height direction of the battery cell and passing through the electrode assembly; the current collecting component is located in the accommodating cavity and is electrically connected to the pole ear; the pressure relief component is connected to the shell, and the side of the pressure relief component facing the electrode assembly is fluidically connected to the central hole; wherein the current collecting component comprises at least one fluid channel, and the fluid channel is constructed to fluidically connect the gap between the electrode assembly and the shell with the central hole.

[0006] In the technical solution of the embodiment of the present application, by providing a fluid channel in the current collecting component that connects the gap between the electrode assembly and the shell and the center hole, a guide can be provided for the gas flow inside the battery cell, thereby facilitating guiding the gas to the location of the pressure relief component and achieving smooth exhaust.

[0007] In some embodiments, the current collecting member includes a first portion disposed opposite to the central hole, and a first surface of the current collecting member facing the electrode assembly is formed with a concave cavity in the first portion; the fluid channel is in fluid communication with the central hole through the concave cavity. Providing the concave cavity can store more gas, and can also simplify the fluid connection between the fluid channel and the central hole, forming a more reliable gas guide channel.

[0008] In some embodiments, a first protrusion is formed on the first portion of the second surface of the current collecting member facing away from the electrode assembly, and the first protrusion is located on the back of the cavity. Providing the first protrusion on the back of the cavity can increase the thickness of the cavity, thereby enhancing the structural strength of the first portion of the current collecting member and improving the deformation resistance of the current collecting member.

[0009] In some embodiments, the first portion is provided with a through hole penetrating the current collecting member, and the orthographic projection of the central hole on the current collecting member at least partially overlaps with the through hole. This is conducive to discharging the airflow in the central hole to prevent the airflow from accumulating in the central hole, while reducing the kinetic energy loss of the airflow, making the exhaust smoother and improving the exhaust efficiency.

[0010] In some embodiments, the current collecting member further comprises a second portion located at the periphery of the first portion and connected to the first portion, the first surface is provided with a groove used as a fluid channel in the second portion, one end of the groove is communicated with the concave cavity, and the other end is communicated with the gap between the electrode assembly and the shell. This is conducive to reducing the volume of the battery cell occupied by the current collecting member, thereby helping to improve the energy density of the battery cell.

[0011] In some embodiments, at least one second protrusion is formed on the first portion of the second surface of the current collecting member facing away from the electrode assembly, and the second protrusion is located on the back side of the groove and is arranged one-to-one with the groove. By arranging the second protrusion on the back side of the groove, a raised reinforcing rib can be formed where the fluid channel is located, thereby enhancing the deformation resistance of the current collecting member and improving the quality of the battery cell.

[0012] In some embodiments, there are multiple fluid channels, and the multiple fluid channels are arranged at intervals along the circumference of the flow collecting component. This can increase the exhaust volume and improve the exhaust efficiency on the one hand, and make the exhaust more uniform on the other hand.

[0013] In some embodiments, the second portion includes a plurality of tab connection portions that are spaced apart along the circumferential direction and are electrically connected to the tabs, and the fluid channel is located between two adjacent tab connection portions. The fluid channel is arranged between two adjacent tab connection portions, and the shape and flowability of the fluid channel can be maintained by the fixed connection between the tab connection portions and the tabs, thereby achieving reliable gas communication and improving the smoothness of exhaust.

[0014] In some embodiments, the fluid channel includes a first end in fluid communication with the central hole, and a second end in fluid communication with the gap between the electrode assembly and the shell, and the cross-sectional area of ​​the fluid channel gradually decreases from the first end to the second end. This can accelerate the flow rate of the airflow from the gap between the electrode assembly and the shell to the center of the current collecting member and form a pressure drop, thereby achieving better convergence and guidance, and making the exhaust smoother.

[0015] In some embodiments, the housing includes a housing body and an end cover, the housing body defines a receiving cavity and an opening at one end of the receiving cavity; the end cover is connected to the housing body to cover the opening; and wherein the pressure relief component is located on the end cover, and the orthographic projection of the center hole on the end cover overlaps at least partially with the pressure relief component. Placing the pressure relief component on the end cover and opposite to the center hole facilitates directional valve opening and improves the reliability of valve opening by the pressure relief component.

[0016] In some embodiments, the tabs include a first tab and a second tab of different polarities, the first tab and the second tab are respectively located at two ends of the main body along the extension direction of the central hole; the current collecting component is a first current collecting component electrically connected to the first tab, or the current collecting component is a second current collecting component electrically connected to the second tab. The tabs of different polarities and the corresponding current collecting components are respectively located at two ends of the electrode assembly, which is beneficial for connecting the two during assembly, and is also beneficial for introducing gas into the central hole, thereby improving the efficiency of gas discharge.

[0017] An embodiment of the second aspect of the present application provides a battery, which includes the battery cell in the above embodiment.

[0018] An embodiment of the third aspect of the present application provides an electrical device, which includes the battery in the above embodiment, and the battery is used to provide electrical energy.

[0019] The above description is only an overview of the technical solution of the present application. In order to more clearly understand the technical means of the present application, it can be implemented in accordance with the contents of the specification. In order to make the above and other purposes, features and advantages of the present application more obvious and easy to understand, the specific implementation methods of the present application are listed below. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] In the accompanying drawings, unless otherwise specified, the same reference numerals throughout the multiple drawings represent the same or similar parts or elements. These drawings are not necessarily drawn to scale. It should be understood that these drawings only depict some embodiments disclosed in the present application and should not be regarded as limiting the scope of the present application.

[0021] Figure 1 A schematic diagram of the structure of a vehicle according to some embodiments of the present application;

[0022] Figure 2 A schematic diagram of the exploded structure of a battery according to some embodiments of the present application;

[0023] Figure 3 A schematic diagram of the structure of a battery cell in some embodiments of the present application;

[0024] Figure 4 for Figure 3 The cross-sectional view along the AA direction;

[0025] Figure 5 A schematic diagram of the structure of a current collecting component in some embodiments of the present application;

[0026] Figure 6 for Figure 5 The cross-sectional view along the BB direction;

[0027] Figure 7 for Figure 5 Cross-sectional view along CC direction;

[0028] Figure 8 for Figure 5 Side view along the D direction;

[0029] Fig. 9 A top view of a current collecting component according to some embodiments of the present application;

[0030] Fig.10 Schematic diagram of the structure of current collecting components of other embodiments of the present application.

[0031] Description of reference numerals:

[0032] Vehicles 1000;

[0033] Battery 100, controller 200, motor 300;

[0034] Box body 10, first part 11, second part 12;

[0035] Battery cell 20, shell 21, shell body 211, end cover 212, electrode assembly 22, main body 221, center hole 2211, pole ear 222, first pole ear 2221, second pole ear 2222, current collecting member 23, first current collecting member 231, second current collecting member 232, first surface 231A, second surface 231B, first part 2311, second part 2312, fluid channel 2313, concave cavity 2311A, first protrusion 2311B, groove 2312A, second protrusion 2312B, through hole 2314, pole ear connecting portion 2315, pressure relief component 24, electrode terminal 25. DETAILED DESCRIPTION

[0036] The following embodiments of the technical solution of the present application are described in detail in conjunction with the accompanying drawings. The following embodiments are only used to more clearly illustrate the technical solution of the present application, and are therefore only used as examples, and cannot be used to limit the scope of protection of the present application.

[0037] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by technicians in the technical field to which this application belongs; the terms used herein 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 figure descriptions and any variations thereof are intended to cover non-exclusive inclusions.

[0038] In the description of the embodiments of the present application, the technical terms "first", "second", etc. are only used to distinguish different objects, and cannot be understood as indicating or implying relative importance or implicitly indicating the number, specific order or primary and secondary relationship of the indicated technical features. In the description of the embodiments of the present application, the meaning of "multiple" is more than two, unless otherwise clearly and specifically defined.

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

[0040] In the description of the embodiments of the present application, the term "and / or" is only a description of the association relationship of the associated objects, indicating that there may 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 article generally indicates that the associated objects before and after are in an "or" relationship.

[0041] In the description of the embodiments of the present application, the term "multiple" refers to more than two (including two). Similarly, "multiple groups" refers to more than two groups (including two groups), and "multiple pieces" refers to more than two pieces (including two pieces).

[0042] In the description of the embodiments of the present application, the technical terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise", "axial", "radial", "circumferential", etc. indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, which are only for the convenience of describing the embodiments of the present application and simplifying the description, and do not indicate or imply that the referred device or element must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the embodiments of the present application.

[0043] In the description of the embodiments of the present application, unless otherwise clearly specified and limited, technical terms such as "installed", "connected", "connected", "fixed" and the like 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 mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, and it can be the internal connection of two elements or the interaction relationship between two elements. For those of ordinary skill in the art, the specific meanings of the above terms in the embodiments of the present application can be understood according to the specific circumstances.

[0044] At present, from the perspective of market development, the application of power batteries is becoming more and more extensive. Power batteries are not only used in energy storage power systems such as hydropower, thermal power, wind power and solar power stations, but also widely used in electric vehicles such as electric bicycles, electric motorcycles, electric cars, as well as military equipment and aerospace and other fields. With the continuous expansion of the application field of power batteries, the market demand is also constantly expanding.

[0045] The electrode assembly of the battery cell will generate gas during the charging and discharging process. In order to avoid accidents caused by excessive pressure inside the battery cell due to excessive gas, a pressure relief component can be set on the battery cell so that the gas pressure inside the battery cell can be discharged from the location of the pressure relief component when it reaches a certain level. However, due to the compact internal structure of the battery cell shell, the path for gas flow is easily blocked. For example, in a cylindrical battery cell, both ends of the electrode assembly will be fixedly connected with a disc-shaped current collecting component. The current collecting component itself and the weld marks formed by welding it with the tabs and electrode terminals will block the flow direction of the gas, so that most of the gas is confined to the gap between the shell and the electrode assembly, and it is difficult to smoothly reach the location of the pressure relief component, resulting in poor exhaust or inability to exhaust in a directional manner.

[0046] In order to alleviate the problem of poor exhaust, a fluid channel can be designed to provide a passage for the gas flow within the battery cell, so that the gas generated by the electrode assembly can flow smoothly to the location of the pressure relief component, and when the pressure reaches a certain level, the pressure relief component will rupture and be discharged from the inside of the battery cell.

[0047] Based on this, the embodiment of the present application provides a battery cell, including a shell, an electrode assembly, a current collecting component and a pressure relief component; the shell includes a housing chamber, the electrode assembly is located in the housing chamber, the electrode assembly includes a main body and a pole ear protruding from the main body, the main body has a central hole extending along the height direction of the battery cell and penetrating the electrode assembly; the current collecting component is located in the housing chamber and is electrically connected to the pole ear; the pressure relief component is connected to the shell, and the side of the pressure relief component facing the electrode assembly is in fluid communication with the central hole; wherein the current collecting component includes at least one fluid channel, and the fluid channel is configured to fluidly connect the gap between the electrode assembly and the shell and the central hole. By providing a fluid channel in the current collecting component that connects the gap between the electrode assembly and the shell and the central hole, a guiding effect can be provided for the gas flow inside the battery cell, thereby facilitating the gas to be guided to the position where the pressure relief component is located, and achieving smooth exhaust.

[0048] The battery cells disclosed in the embodiments of the present application can be used in, but not limited to, electrical devices such as vehicles, ships or aircraft. A power supply system comprising the battery cells and batteries disclosed in the present application can be used to form the electrical device, which is helpful to alleviate the poor exhaust of the battery cells and improve the reliability of the battery.

[0049] The embodiment of the present application provides an electric device using a battery as a power source, and the electric device may be, but is not limited to, a mobile phone, a tablet, a laptop, an electric toy, an electric tool, a battery car, an electric car, a ship, a spacecraft, etc. Among them, the electric toy may include a fixed or mobile electric toy, such as a game console, an electric car toy, an electric ship toy, and an electric airplane toy, etc., and the spacecraft may include an airplane, a rocket, a space shuttle, and a spacecraft, etc.

[0050] For the convenience of description, the following embodiments are described by taking a vehicle 1000 as an example of an electrical device according to an embodiment of the present application.

[0051] Please refer to Figure 1 , Figure 1 A schematic diagram of the structure of a vehicle provided for some embodiments of the present application. Vehicle 1000 may be a fuel vehicle, a gas vehicle or a new energy vehicle, and the new energy vehicle may be a pure electric vehicle, a hybrid vehicle or an extended-range vehicle, etc. A battery 100 is provided inside the vehicle 1000, and the battery 100 may be provided at the bottom, head or tail of the vehicle 1000. The battery 100 may be used to power the vehicle 1000, for example, the battery 100 may be used as an operating power source for the vehicle 1000. The vehicle 1000 may also include a controller 200 and a motor 300, and the controller 200 is used to control the battery 100 to power the motor 300, for example, for starting, navigating and driving the vehicle 1000.

[0052] In some embodiments of the present application, the battery 100 can not only serve as an operating power source for the vehicle 1000, but also serve as a driving power source for the vehicle 1000, replacing or partially replacing fuel or natural gas to provide driving power for the vehicle 1000.

[0053] Please refer to Figure 2 , Figure 2 Schematic diagram of the exploded structure of the battery provided for some embodiments of the present application. The battery 100 includes a box 10 and a battery cell 20, and the battery cell 20 is contained in the box 10. Among them, the box 10 is used to provide a storage space for the battery cell 20, and the box 10 can adopt a variety of structures. In some embodiments, the box 10 may include a first part 11 and a second part 12, the first part 11 and the second part 12 cover each other, and the first part 11 and the second part 12 jointly define a storage space for accommodating the battery cell 20. The second part 12 can be a hollow structure with one end open, the first part 11 can be a plate-like structure, and the first part 11 covers the open side of the second part 12, so that the first part 11 and the second part 12 jointly define a storage space; the first part 11 and the second part 12 can also be hollow structures with one side open, and the open side of the first part 11 covers the open side of the second part 12. Of course, the box 10 formed by the first part 11 and the second part 12 can be in a variety of shapes, such as a cylinder, a cuboid, etc.

[0054] In the battery 100, there may be multiple battery cells 20, and the multiple battery cells 20 may be connected in series, in parallel, or in a mixed connection. A mixed connection means that the multiple battery cells 20 are both connected in series and in parallel. The multiple battery cells 20 may be directly connected in series, in parallel, or in a mixed connection, and then the whole formed by the multiple battery cells 20 is accommodated in the box 10; of course, the battery 100 may also be a battery module formed by connecting multiple battery cells 20 in series, in parallel, or in a mixed connection, and then the multiple battery modules are connected in series, in parallel, or in a mixed connection to form a whole, and accommodated in the box 10. The battery 100 may also include other structures, for example, the battery 100 may also include a busbar component for realizing electrical connection between the multiple battery cells 20.

[0055] The battery cell 20 refers to the smallest unit that constitutes the battery, wherein each battery cell 20 can be a secondary battery or a primary battery; it can also be a lithium-sulfur battery, a sodium-ion battery or a magnesium-ion battery, but is not limited thereto. The battery cell 20 can be cylindrical, flat, rectangular or other shapes. Unless otherwise specified, the embodiments of the present application are described by taking a cylindrical battery cell as an example.

[0056] Please refer to Figure 3-Figure 5 , Figure 3 A schematic diagram of the structure of a battery cell provided in some embodiments of the present application, Figure 4 for Figure 3 The cross-sectional view along the AA direction is shown in Figure 2. Figure 5 A schematic structural diagram of a current collecting component provided in some embodiments of the present application.

[0057] The embodiment of the present application provides a battery cell 20, which includes a shell 21, an electrode assembly 22, a current collecting component 23 and a pressure relief component 24; the shell 21 includes a accommodating cavity, the electrode assembly 22 is located in the accommodating cavity, the electrode assembly 22 includes a main body 221 and a pole ear 222 protruding from the main body 221, the main body 221 has a central hole 2211 extending along the height direction of the battery cell 20 and penetrating the electrode assembly 22; the current collecting component 23 is located in the accommodating cavity and is electrically connected to the pole ear 222; the pressure relief component 24 is connected to the shell 21, and the side of the pressure relief component 24 facing the electrode assembly 22 is fluidically connected to the central hole 2211; wherein the current collecting component 23 includes at least one fluid channel 2313, and the fluid channel 2313 is constructed to fluidically connect the gap between the electrode assembly 22 and the shell 21 and the central hole 2211.

[0058] The shell 21 is a component for forming the internal environment of the battery cell 20, wherein the formed internal environment can be used to accommodate the electrode assembly 22, the electrolyte and other components. The shell 21 can be of various shapes and sizes, such as a rectangular parallelepiped, a cylindrical shape, a hexagonal prism, etc. Specifically, the shape of the shell 21 can be determined according to the specific shape and size of the electrode assembly 22. The material of the shell 21 can be various, such as copper, iron, aluminum, stainless steel, aluminum alloy, plastic, etc.

[0059] The electrode assembly 22 is a component in the battery cell 20 where electrochemical reactions occur. One or more electrode assemblies 22 may be included in the housing 21. The electrode assembly 22 is mainly formed by winding or stacking positive and negative electrode sheets, and a separator is usually provided between the positive and negative electrode sheets. The parts of the positive and negative electrode sheets with active materials constitute the main body 221 of the electrode assembly 22, and the parts of the positive and negative electrode sheets without active materials each constitute a pole ear 222. The pole ear 222 protrudes relative to the main body 221 to facilitate connection with the current collecting member 23. The pole ears of different polarities can be located together at one end of the main body or at both ends of the main body 221. During the charge and discharge process of the battery, the positive active material and the negative active material react with the electrolyte, and the pole ear 222 connects the electrode terminal to form a current loop. The center of the electrode assembly 22 has a central hole 2211 formed by winding the pole sheet, and the central hole 2211 extends along the height direction of the battery cell 20 and penetrates the electrode assembly 22. The center hole 2211 may be a cylindrical through hole, and the central axis of the center hole 2211 may be coaxial with the central axis of the shell 21. It is understandable that, in order to facilitate the insertion of the electrode assembly 22 and to accommodate the electrolyte, the inner diameter of the shell 21 is larger than the outer diameter of the electrode assembly 22, which results in a certain gap between the electrode assembly 22 and the shell 21.

[0060] The current collecting member 23 is a component that electrically connects the tabs 222 and the electrode terminals, respectively. The current collecting member 23 may include a first current collecting member 231 and a second current collecting member 232 connected to tabs of different polarities. The first current collecting member 231 and the second current collecting member 232 may be arranged according to the positions of the corresponding tabs, for example, respectively arranged at both ends of the main body 221. The current collecting member 23 may be made of a conductive material, such as copper or a copper alloy. The current collecting member 23 may be electrically connected to the tabs 222 or the electrode terminals by welding, such as laser welding, ultrasonic welding, or friction welding. The current collecting component 23 includes a first surface 231 facing the electrode assembly 22 and a second surface 232 facing away from the electrode assembly 22. The fluid channel 2313 can be set on the first surface 231 or the second surface 232. The two ends of the fluid channel 2313 are respectively connected to the center hole 2211 and the gap between the electrode assembly 22 and the shell 21, so that the gas generated by the electrode assembly 22 can flow from the gap between the electrode assembly 22 and the shell 21 to the center hole 2211, and flow to the position of the pressure relief component 24 through the center hole 2211.

[0061] The pressure relief component 24 is constructed to break when the internal pressure of the battery cell 20 reaches a certain threshold, so that the gas inside the battery cell 20 can be discharged to reduce the internal air pressure. The pressure relief component 24 can be an independent component connected to the shell 21, or it can be a component formed on the shell 21 and integrated with the shell 21. For example, a structural weak part is formed on the shell 21 as the pressure relief component 24. When the internal pressure of the battery cell 20 increases to a certain level, the structural weak part will be destroyed first to allow the gas to be discharged for pressure relief. In some embodiments, the pressure relief component 24 can be a structural weak part formed by one or more notched grooves set at a specified position of the shell 21.

[0062] By providing a fluid channel 2313 in the current collecting component 23 that connects the gap between the electrode assembly 22 and the shell 21 and the center hole 2211, guidance can be provided for the gas flow inside the battery cell 20, which is beneficial for guiding the gas to the position where the pressure relief component 24 is located, thereby achieving pressure relief at the designated position and smooth exhaust.

[0063] See also Figure 5-Figure 8 , Figure 5 A schematic diagram of the structure of a current collecting component in some embodiments of the present application; Figure 6 for Figure 5 The cross-sectional view along the BB direction; Figure 7 for Figure 5 Cross-sectional view along CC direction; Figure 8 for Figure 5 Side view along the D direction.

[0064] According to some embodiments of the present application, the current collecting member 23 includes a first portion 2311 arranged opposite to the central hole 2211, and a first surface 231A of the current collecting member 23 facing the electrode assembly 22 is formed with a cavity 2311A in the first portion 2311; the fluid channel 2313 is fluidically connected to the central hole 2211 through the cavity 2311A.

[0065] like Figure 5 and Figure 6As shown, the current collecting member 23 can be a first current collecting member 231 or a second current collecting member 232. The first portion 2311 can be located in the central area of ​​the current collecting member 23 and arranged opposite to the central hole 2211. The first surface 231A is recessed inwardly in the first portion 2311 to form a concave cavity 2311A. The cross-sectional shape of the concave cavity 2311A can be arbitrary, such as a circle, a polygon or other irregular shapes. The fluid channel 2313 can be directly connected to the concave cavity 2311A to achieve fluid communication with the central hole 2211. The fluid channel 2313 can be connected to the side wall of the concave cavity 2311A or to the top of the concave cavity 2311A. In some embodiments, the second surface 231B can be a flat surface, so that although the thickness of the current collecting member 23 at the location of the concave cavity 2311A is relatively thin, the overall thickness of the current collecting member 23 can be reduced, which is beneficial to improving the energy density of the battery cell 20.

[0066] By providing the concave cavity 2311A, a gas accommodating space can be formed between the electrode assembly 22 and the current collecting member 23, which is convenient for storing more gas. At the same time, the fluid connection between the fluid channel 2313 and the central hole 2211 can also be simplified to form a more reliable gas guiding channel.

[0067] According to some embodiments of the present application, Figure 6 As shown, a first protrusion 2311B is formed on the first portion 2311 of the second surface 231B of the current collecting member 23 facing away from the electrode assembly 22 , and the first protrusion 2311B is located on the back side of the cavity 2311A.

[0068] The first protrusion 2311B and the concave cavity 2311A are respectively located on two surfaces of the same part of the current collecting member 23 , and the two can be formed by one-time processing, for example, the first protrusion 2311B and the concave cavity 2311A can be obtained by stamping the first portion 2311 in the central area of ​​the flat current collecting member 23 .

[0069] The current collecting member 23 may be a first current collecting member 231, and a second surface 231B of the first current collecting member 231 may be electrically connected to the electrode terminal 25. In some embodiments, the electrode terminal 25 may be welded to the first protrusion 2311B protruding upward of the current collecting member 23, so that the welding position of the electrode terminal 25 may be staggered with the welding position of the tab 222, thereby preventing the mutual influence between the two.

[0070] Providing the first protrusion 2311B on the back side of the cavity 2311A can increase the thickness of the cavity 2311A, thereby enhancing the structural strength of the first portion 2311 of the current collecting member 23 and improving the deformation resistance of the current collecting member, while also facilitating the connection between the current collecting member 23 and the electrode terminal 25.

[0071] According to some embodiments of the present application, Figure 4 and Figure 5 As shown, the first portion 2311 is provided with a through hole 2314 penetrating the current collecting member 23 , and the orthographic projection of the central hole 2211 on the current collecting member 23 at least partially overlaps with the through hole 2314 .

[0072] The through hole 2314 may be a hole of any shape, such as a circle. The number of through holes 2314 may be one or more. In some embodiments, the through hole 2314 is located in the central area of ​​the current collecting member 23, and the center line of the through hole 2314 may coincide with the center line of the center hole 2211. In this way, the gas gathered in the fluid channel 2313 may flow through the through hole 2314 to the position where the pressure relief component 24 on the housing 21 is located.

[0073] The through hole 2314 that at least partially overlaps the center hole 2211 is advantageously used to discharge the airflow in the center hole 2211 and flow it to the location of the pressure relief component 24 to prevent the airflow from accumulating in the center hole 2211. In addition, the kinetic energy loss of the airflow can be reduced, making the exhaust smoother and improving the exhaust efficiency.

[0074] According to some embodiments of the present application, Figure 5 and Figure 7 As shown, the current collecting component 23 also includes a second part 2312 located at the periphery of the first part 2311 and connected to the first part 2311, and the first surface 231A is provided with a groove 2312A in the second part 2312 serving as a fluid channel 2313, one end of the groove 2312A is connected to the concave cavity 2311A, and the other end is connected to the gap between the electrode assembly 22 and the shell 21.

[0075] The groove 2312A is a groove-shaped structure formed by the depression of the first surface 231A, and the groove 2312A can extend in the radial direction of the current collecting member 23. The groove 2312A can be a straight line, or a curve, such as an arc or a wavy line. One end of the groove 2312A is connected to the cavity 2311A, and the other end is connected to the gap between the electrode assembly 22 and the shell 21. In this way, the gas accumulated in the gap between the electrode assembly 22 and the shell 21 can flow to the cavity 2311A through the groove 2312A, and flow to the center hole 2211 through the cavity 2311A, and then flow from the center hole 2211 to the position where the pressure relief component 24 is located.

[0076] The groove 2312A can be provided without increasing the thickness of the current collecting member 23 while forming the fluid channel 2313 , which helps to reduce the volume of the battery cell occupied by the current collecting member 23 , thereby helping to improve the energy density of the battery cell.

[0077] According to some embodiments of the present application, Figure 5 , Figure 7 and Figure 8As shown, at least one second protrusion 2312B is formed on the second portion 2312 of the second surface 231B of the current collecting member 23 facing away from the electrode assembly 22 . The second protrusion 2312B is located on the back of the groove 2312A and is arranged one-to-one with the groove 2312A.

[0078] The second protrusion 2312B and the groove 2312A are located on two surfaces at the same position of the current collecting member 23. The number of the second protrusion 2312B can be one or more, and can be the same as the number of the grooves 2312A. In some embodiments, the second protrusion 2312B and the groove 2312A can be formed by stamping the disc-shaped current collecting member 23. In other embodiments, the height of the second protrusion 2312B can be the same as the height of the first protrusion 2311B, thereby improving the utilization rate of the internal space of the battery cell.

[0079] By providing the second protrusion 2312B on the back side of the groove 2312A, a protruding reinforcing rib can be formed where the fluid channel 2313 is located, thereby enhancing the anti-deformation capability of the current collecting member 23 and improving the quality of the battery cell.

[0080] According to some embodiments of the present application, Figure 5 As shown, there are multiple fluid channels 2313 , and the multiple fluid channels 2313 are arranged at intervals along the circumference of the current collecting component 23 .

[0081] The plurality of fluid channels 2313 may be evenly spaced around the circumference of the concave cavity 2311A. The structural forms of the plurality of fluid channels 2313 may be the same or different. In some embodiments, the fluid channels 2313 may be disposed on the second portion 2312 of the current collecting member 23, or on the side wall of the concave cavity 2311A formed in the first portion 2311 of the current collecting member 23.

[0082] Providing a plurality of fluid channels 2313 spaced apart along the circumferential direction can guide the airflow in the gaps at different circumferential positions within the battery cell 20 , which can increase the exhaust volume and improve the exhaust efficiency on the one hand, and make the exhaust more uniform on the other hand.

[0083] See also Fig. 9 , Fig. 9 This is a top view of the current collecting component in some embodiments of the present application.

[0084] According to some embodiments of the present application, the second portion 2312 includes a plurality of tab connecting portions 2315 that are spaced apart along the circumferential direction and are electrically connected to the tabs 222 , respectively, and the fluid channel 2313 is located between two adjacent tab connecting portions 2315 .

[0085] The tab connection portion 2315 is a region for connecting with the tab 222. The specific connection method may be laser welding or ultrasonic welding, so that the tab 222 and the tab connection portion 2315 of the current collecting member 23 are melted and connected together. The sizes and shapes of the multiple tab connection portions 2315 may be the same or different. In some embodiments, the tab connection portion 2315 and the fluid channel 2313 are sequentially spaced along the circumferential direction.

[0086] The fluid channel 2313 is arranged between two adjacent pole lug connecting portions 2315 , and the shape and flowability of the fluid channel 2313 can be maintained by the fixed connection between the pole lug connecting portion 2315 and the pole lug 222 , thereby achieving reliable gas connectivity and improving the smoothness of exhaust.

[0087] See also Fig.10 , Fig.10 Schematic diagram of the structure of the current collecting component in other embodiments of the present application.

[0088] According to some embodiments of the present application, the fluid channel 2313 includes a first end connected to the fluid of the center hole 2211, and a second end connected to the gap between the electrode assembly 22 and the shell 21, and the cross-sectional area of ​​the fluid channel 2313 gradually decreases from the first end to the second end.

[0089] In some embodiments, the current collecting member 23 is disc-shaped, and the fluid channel 2313 extends from the concave cavity 2311A in the central area of ​​the current collecting member 23 to the edge of the current collecting member 23 to respectively connect the central hole 2211 and the gap between the electrode assembly 22 and the shell 21. The first end of the fluid channel 2313 is an end close to the central hole 2211, and the first end can be directly connected to the concave cavity 2311A, and the second end is an end away from the central hole 2211 and located at the edge of the current collecting member 23. The cross-section of the fluid channel 2313 can be polygonal or semicircular. In some embodiments, the cross-section of the fluid channel 2313 is rectangular, and the width of the rectangle gradually increases in the direction from the first end to the second end.

[0090] The change in the size of the cross-sectional area of ​​the fluid channel 2313 can accelerate the flow rate of the airflow from the gap between the electrode assembly 22 and the shell 21 to the center of the current collecting component 23 and form a pressure drop, thereby playing a better convergence and guiding role and making the exhaust smoother.

[0091] According to some embodiments of the present application, Figure 4 As shown, the shell 21 includes a shell body 211 and an end cover 212, the shell body 211 defines a accommodating cavity and an opening located at one end of the accommodating cavity; the end cover 212 is connected to the shell body 211 to cover the opening; and wherein the pressure relief component 24 is located on the end cover 212, and the orthographic projection of the center hole 2211 on the end cover 212 at least partially overlaps with the pressure relief component 24.

[0092] The shell body 211 and the end cover 212 may be independent components, and an opening may be provided on the shell body 211, and the end cover 212 may be closed at the opening to form an internal environment of the battery cell 20. Without limitation, the end cover 212 and the shell body 211 may be integrated, and specifically, the end cover 212 and the shell body 211 may form a common connection surface before other components are put into the shell, and when the interior of the shell body 211 needs to be encapsulated, the end cover 212 may be closed with the shell body 211.

[0093] The housing body 211 may include a bottom wall and side walls connected to each other. The bottom wall is provided with a through hole to allow the electrode terminal 25 to pass through and be electrically connected to the electrode assembly 23 .

[0094] The end cap 212 refers to a component that covers the opening of the shell body 211 to isolate the internal environment of the battery cell 20 from the external environment. Without limitation, the shape of the end cap 212 can be adapted to the shape of the shell body 211 to match the shell body 211. Optionally, the end cap 212 can be made of a material with a certain hardness and strength (such as aluminum alloy), so that the end cap 212 is not easily deformed when squeezed and collided, so that the battery cell 20 can have a higher structural strength and the safety performance can also be improved. Functional components such as electrode terminals can be provided on the end cap 212. The electrode terminal can be used to electrically connect to the electrode assembly 22 for outputting or inputting electrical energy of the battery cell 20. The material of the end cap 212 can also be a variety of materials, such as copper, iron, aluminum, stainless steel, aluminum alloy, plastic, etc. In some embodiments, an insulating member can also be provided on the inner side of the end cap 212, and the insulating member can be used to isolate the electrical connection components in the shell body 211 from the end cap 212 to reduce the risk of short circuit. For example, the insulating member may be plastic, rubber, or the like.

[0095] The end cover 212 may also be provided with a pressure relief component 24 for releasing the internal pressure when the internal pressure of the battery cell 20 reaches a threshold value. The pressure relief component 24 may be an independent component or a partial weak area on the end cover 212, which ruptures to release the internal pressure when the internal pressure of the battery cell reaches a threshold value.

[0096] In some embodiments, the pressure relief component 24 may be located in the central area of ​​the end cap 212 and disposed directly opposite to the central hole 2211 of the electrode assembly 22. It is understandable that when a current collecting member 23 is further disposed between the electrode assembly 22 and the end cap 212, the central hole 2211 of the electrode assembly 22 and the through hole 2314 on the current collecting member 23 at least partially overlap, and the projections of the two on the end cap 212 along the extension direction of the central hole 2211 at least partially overlap with the position of the pressure relief component 24, so that the gas introduced into the central hole 2211 can flow directly to the position of the pressure relief component 24, and can directly break through the pressure relief component 24 and then be discharged from the battery cell 20 when the pressure reaches the threshold.

[0097] Disposing the pressure relief component 24 on the end cover 212 and opposite to the center hole 2211 is helpful for directional valve opening and improves the reliability of the pressure relief component 24 in opening the valve.

[0098] According to some embodiments of the present application, the pole ear 222 includes a first pole ear 2221 and a second pole ear 2222 with different polarities, and the first pole ear 2221 and the second pole ear 2222 are respectively located at both ends of the main body 221 along the extension direction of the center hole 2211; the current collecting component 23 can be a first current collecting component 231 electrically connected to the first pole ear 2221, or a second current collecting component 232 electrically connected to the second pole ear 2222.

[0099] The first pole tab 2221 may be a positive pole tab, and the second pole tab 2222 may be a negative pole tab. The first pole tab 2221 and the second pole tab 2222 protrude toward both ends of the main body 221, respectively. The first surface 231A of the first current collecting member 231 is electrically connected to the first pole tab 2221, and the second surface 231B is electrically connected to the electrode terminal 25 that passes through the shell body 211 and is insulated from the shell body 211. The second current collecting member 232 is located between the second pole tab 2222 and the end cover 212, and is electrically connected to the second pole tab 222 and the end cover 212, respectively, so that the shell 21 serves as another electrode terminal of the battery cell 20.

[0100] In some embodiments, the current collecting member 23 may be any one of the first current collecting member 231 and the second current collecting member 232, so that the gas in the gap between the electrode assembly 22 and the shell 21 can enter the central hole 2211 through the fluid channel 2313, and finally reach the position of the pressure relief component 24. In other embodiments, the structures of the first current collecting member 231 and the second current collecting member 232 are the same as those of the current collecting member 23, that is, both are provided with at least one fluid channel 2313.

[0101] The pole ears 222 and the current collecting member 23 of different polarities are respectively located at the two ends of the electrode assembly 22, which is beneficial for connecting the two during assembly and also beneficial for introducing gas into the central hole 2211 to improve the efficiency of gas discharge.

[0102] The embodiment of the present application provides a battery 100 , which includes the battery cell 20 in the above embodiment.

[0103] An embodiment of the present application provides an electrical device, which includes the battery 100 in the above embodiment, and the battery 100 is used to provide electrical energy.

[0104] The battery cell 20 of the present application is further described in detail below in conjunction with a specific embodiment.

[0105] like Figure 3-Figure 10 As shown, the battery cell 20 is a cylindrical battery, and the battery cell 20 includes a housing 21 , an electrode assembly 22 , a current collecting member 23 , a pressure relief component 24 , and an electrode terminal 25 .

[0106] The housing 21 includes a housing body 211 and an end cap 212. The housing body 211 includes a bottom wall and a side wall connected to each other, the bottom wall and the side wall forming a receiving cavity and an opening at one end of the receiving cavity away from the bottom wall. The end cap 212 is connected to the side wall to cover the opening.

[0107] The electrode assembly 22 is located in the accommodating cavity, and the electrode assembly 22 includes a main body 221 and a pole ear 222. The pole ear 222 includes a first pole ear 2221 and a second pole ear 2222 respectively located at both ends of the main body 221 and protruding from the main body 221. The main body 221 has a central hole 2211 extending along the height direction of the battery cell 20 and penetrating the electrode assembly 22.

[0108] The battery cell 20 includes a first current collecting member 231 and a second current collecting member 232 located at both ends of the main body 221 in the accommodating cavity. The first current collecting member 231 is electrically connected to the first pole tab 2221, and the second current collecting member 232 is electrically connected to the second pole tab 2222. The current collecting member 23 can be the first current collecting member 231 or the second current collecting member 232.

[0109] The structures of the first current collecting member 231 and the second current collecting member 232 can be the same, both of which include a first part 2311 located in the center and a second part 2312 connected to the first part 2311 and circumferentially surrounding the first part 2311, as well as a first surface 231A facing the electrode assembly 22 and a second surface 231B facing the electrode assembly 22, the first surface 231A is recessed in the first part 2311 to form a cavity 2311A, the first surface 231A is recessed in the second part 2312 to form at least one groove 2312A used as a fluid channel 2313, one end of the groove 2312A is connected to the cavity 2311A, and the other end is connected to the gap between the electrode assembly 22 and the shell 21.

[0110] The second surface 231B has a first protrusion 2311B formed on the first portion 2311, and the first protrusion 2311B is located on the back side of the cavity 2311A. The second surface 231B has at least one second protrusion 2312B formed on the second portion 2312, and the second protrusion 2312B is located on the back side of the groove 2312A and is arranged one-to-one with the groove 2312A.

[0111] A through hole 2314 is further provided at the center of the first portion 2311 , and the central axis of the through hole 2314 coincides with the central axis of the central hole 2211 .

[0112] The second part 2312 is also provided with a plurality of pole ear connecting parts 2315 connected to the pole ears, the fluid channel 2313 is located between two adjacent pole ear connecting parts 2315, and the plurality of fluid channels 2313 are arranged at circumferential intervals around the first part 2311, the fluid channel 2313 includes a first end connected to the fluid of the center hole 2211, and a second end connected to the gap between the electrode assembly 22 and the shell 21, and the cross-sectional area of ​​the fluid channel 2313 is a constant from the first end to the second end, or gradually decreases from the first end to the second end.

[0113] The pressure relief component 24 is located on the end cover 212 , and the orthographic projections of the central hole 2211 and the through hole 2314 on the end cover 212 are located within the range of the pressure relief component 24 .

[0114] The electrode terminal 25 is insulated through the bottom wall of the case body 211 and is welded to the second surface 231B of the first current collecting member 231 to achieve electrical connection. The second current collecting member 232 is welded to the end cap 212 to achieve electrical connection.

[0115] The gas generated by the electrode assembly 22 in the battery cell 20 of this embodiment can be collected and guided into the center hole 2211 through the fluid channel 2313, and flow along the center hole 2211 to the position of the pressure relief component 24. When the pressure reaches a certain threshold, the pressure relief component 24 ruptures so that the gas can be discharged smoothly from the interior of the battery cell 20, realizing directional valve opening and smooth exhaust.

[0116] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present application, rather than to limit them; although the present application has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or replace some or all of the technical features therein by equivalents; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the scope of the technical solutions of the embodiments of the present application, and they should all be included in the scope of the claims and specification of the present application. In particular, as long as there is no structural conflict, the various technical features mentioned in the various embodiments can be combined in any way. The present application is not limited to the specific embodiments disclosed herein, but includes all technical solutions that fall within the scope of the claims.

Claims

1. A battery cell, characterized in that: include: The housing includes a receiving cavity, An electrode assembly is located in the accommodating cavity, the electrode assembly comprises a main body and a pole ear protruding from the main body, the main body has a central hole extending along the height direction of the battery cell and penetrating the electrode assembly; A current collecting component is located in the accommodating cavity and is electrically connected to the tab; and A pressure relief component connected to the housing, wherein a side of the pressure relief component facing the electrode assembly is in fluid communication with the central hole; The current collecting member includes at least one fluid channel, and the fluid channel is configured to fluidically connect the gap between the electrode assembly and the shell with the central hole.

2. The battery cell according to claim 1, characterized in that: The current collecting member includes A first portion disposed opposite to the central hole, a first surface of the current collecting member facing the electrode assembly having a concave cavity formed in the first portion; The fluid passage is in fluid communication with the central bore through the recessed cavity.

3. The battery cell according to claim 2, characterized in that: A first protrusion is formed on the first portion of a second surface of the current collecting member facing away from the electrode assembly, and the first protrusion is located at the back side of the cavity.

4. The battery cell according to claim 3, characterized in that: The first portion is provided with a through hole penetrating the current collecting member, and the orthographic projection of the central hole on the current collecting member at least partially overlaps with the through hole.

5. The battery cell according to any one of claims 2 to 4, characterized in that: The current collecting member also includes a second portion located at the periphery of the first portion and connected to the first portion, the first surface is provided with a groove serving as the fluid channel in the second portion, one end of the groove is connected to the concave cavity, and the other end is connected to the gap between the electrode assembly and the shell.

6. The battery cell according to claim 5, characterized in that: At least one second protrusion is formed on the first portion of the second surface of the current collecting member facing away from the electrode assembly. The second protrusion is located on the back side of the groove and is arranged one-to-one with the groove.

7. The battery cell according to any one of claims 1 to 6, characterized in that: There are a plurality of fluid channels, which are arranged at intervals along the circumferential direction of the flow collecting component.

8. The battery cell according to claim 5, characterized in that: The second portion includes a plurality of tab connecting portions which are arranged at intervals along the circumferential direction and are electrically connected to the tabs respectively, and the fluid channel is located between two adjacent tab connecting portions.

9. The battery cell according to any one of claims 1 to 8, characterized in that: The fluid channel includes a first end in fluid communication with the central hole, and a second end in fluid communication with a gap between the electrode assembly and the shell, and a cross-sectional area of ​​the fluid channel gradually decreases from the first end to the second end.

10. The battery cell according to any one of claims 1 to 9, characterized in that: The housing comprises: a housing body, defining the accommodating cavity and an opening at one end of the accommodating cavity; and An end cover connected to the housing body to cover the opening; And wherein, the pressure relief component is located on the end cover, and the orthographic projection of the central hole on the end cover at least partially overlaps with the pressure relief component.

11. The battery cell according to any one of claims 1 to 10, characterized in that: The electrode tabs include a first electrode tab and a second electrode tab with different polarities, wherein the first electrode tab and the second electrode tab are respectively located at two ends of the main body along the extension direction of the central hole; The current collecting member is a first current collecting member electrically connected to the first electrode tab, or the current collecting member is a second current collecting member electrically connected to the second electrode tab.

12. A battery, characterized in that: The invention comprises a battery cell as claimed in any one of claims 1 to 11.

13. An electrical device, characterized in that: The electrical device comprises the battery as claimed in claim 12, wherein the battery is used to provide electrical energy.

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