Battery cells, batteries and power consumption devices

Abstract

This application discloses a battery cell, a battery, and a power consumption device. The battery cell includes a housing and an electrode terminal. The housing includes a wall having a withdrawal hole. The electrode terminal is disposed in the withdrawal hole, and the electrode terminal has a weakened area configured to break when the internal pressure of the housing exceeds a pressure threshold or the temperature exceeds a temperature threshold, thereby connecting the interior of the housing to the exterior of the housing. This method reduces the risk of the battery cell bursting.

Description

[Technical Field]

[0001] This application relates to the battery technology field, and more particularly to battery cells, batteries, and power consumption devices. [Background technology]

[0002] With advancements in battery technology, battery cells are being applied to an increasing number of fields, and are increasingly replacing conventional petrochemical energy in the automotive power sector. Battery cells can store chemical energy and controllably convert it into electrical energy. In recyclable battery cells, the active material can be reactivated through a charging method after discharge, allowing for continued use.

[0003] A battery cell often includes an electrode assembly, electrode terminals, and a housing. The electrode assembly is electrically connected to the outside via the electrode terminals. The housing can accommodate the electrode assembly and form a support for it. An electrolyte may be contained inside the housing, and the electrolyte and the active material on the electrode assembly can generate gas, increasing the internal pressure of the housing and posing a risk of the battery cell rupturing. [Overview of the project] [Means for solving the problem]

[0004] In view of the above issues, this application provides a battery cell, a battery, and a power consumption device that can reduce the risk of the battery cell rupturing.

[0005] According to a first aspect, the present application provides a battery cell comprising a housing and electrode terminals. The housing includes a wall portion, the wall portion having an outlet hole. The electrode terminals are provided in the outlet hole, and the electrode terminals have a vulnerable region, which is configured to break when the internal pressure of the housing exceeds a pressure threshold or the temperature exceeds a temperature threshold, thereby creating communication between the inside of the housing and the outside of the housing.

[0006] With the above method, when the pressure exceeds the pressure threshold or the temperature exceeds the temperature threshold, the vulnerable region is destroyed, allowing excess gas from inside the housing to be released, thereby reducing the risk of the battery cell rupturing due to excessively high internal pressure. Placing the vulnerable region at the electrode terminals, compared to placing it in the housing, reduces the possibility of housing deformation and simplifies the assembly of the battery cell.

[0007] In some embodiments, the electrode terminals are provided with notched grooves, and the vulnerable region is formed at the bottom of the notched grooves.

[0008] The above method facilitates the processing of vulnerable areas, and after the pressure exceeds the pressure threshold or the temperature exceeds the temperature threshold, the electrode terminals can be broken or bent along the notch grooves due to the action of the pressure, allowing excess gas inside the housing to be released, thereby reducing the risk of the battery cell rupturing due to excessively high internal pressure.

[0009] In some embodiments, the electrode terminal includes an insertion portion and a first flange portion connected to each other, the insertion portion being inserted into a pull-out hole along the axial direction of the electrode terminal, at least a portion of the outer circumferential surface of the first flange portion protruding from the outer circumferential surface of the insertion portion in the radial direction of the electrode terminal, the portion of the first flange portion positioned around the pull-out hole being supported on the side facing inward towards the housing of the wall portion, where the vulnerable region is located on the insertion portion and / or the first flange portion.

[0010] With the above method, the pressure acting on the insertion section and the first flange section inside the housing is relatively large. Therefore, by placing the vulnerable area on the insertion section or the first flange section, the vulnerable area can be made more sensitive to the pressure inside the housing, making it easier to achieve explosion-proof effects.

[0011] In some embodiments, the electrode terminals are provided with notches, the vulnerable region is formed at the bottom of the notch, and the notch is located on a side facing and / or away from the wall of the first flange portion.

[0012] The above method facilitates machining of the vulnerable area, while generally, the thickness of the first flange portion in the axial direction is relatively thin. As a result, the notched groove is more sensitive to the internal pressure of the housing, making it easier to achieve explosion-proof effects.

[0013] In some embodiments, the notch groove is positioned axially opposite at least a portion of the alignment slit between the outer circumferential surface of the insertion portion and the hole wall of the drawer hole.

[0014] With the above method, when the electrode terminal breaks or bends along the notch groove, it becomes easier to detach from the extraction hole, allowing for rapid pressure release and thus providing a more effective explosion-proof effect.

[0015] In some embodiments, the radial width of the aligning slit is greater than the radial width of the notch groove.

[0016] With the above method, when the electrode terminal breaks or bends along the notch groove, it becomes easier to detach from the extraction hole, allowing for rapid pressure release and thus providing a more effective explosion-proof effect.

[0017] In some embodiments, the projection of the outermost edge of the notch groove in the radial direction along the axial direction falls into the mating slit.

[0018] With the above method, when the electrode terminal breaks or bends along the notch groove, it becomes easier to detach from the extraction hole, allowing for rapid pressure release and thus providing a more effective explosion-proof effect.

[0019] In some embodiments, the radial width of the notch groove is 0.5 mm or more and 2 mm or less in the radial direction.

[0020] In the radial direction, by setting the radial width of the notch groove to 0.5 mm or more, when the internal pressure of the housing exceeds the pressure threshold or the temperature exceeds the temperature threshold, it is advantageous to promote the first flange portion to bend or break along the notch groove. By setting the radial width of the notch groove to 2 mm or less, the first flange portion can maintain sufficient structural strength and improve the structural stability of the battery cell.

[0021] In some embodiments, in the axial direction, the axial depth of the notch groove is 0.1 times or more and 0.9 times or less the axial thickness of the first flange portion.

[0022] In the axial direction, by setting the axial depth of the notch groove to 0.1 times the axial thickness H0 of the first flange portion 230, when the internal pressure of the housing exceeds the pressure threshold or the temperature exceeds the temperature threshold, it is advantageous to promote the first flange portion to bend or break along the notch groove. By setting the axial depth of the notch groove to 0.9 times or less the axial thickness of the first flange portion, the first flange portion can maintain sufficient structural strength and improve the structural stability of the battery cell.

[0023] In some embodiments, at least a part of the weak region is located on the outer peripheral surface of the insertion portion.

[0024] By the above method, while facilitating the processing of the weak region, the insertion portion is likely to form a break along the weak region.

[0025] In some embodiments, the electrode terminal includes an insertion portion and a closing portion that are connected to each other. The insertion portion is inserted into the drawing hole along the axial direction of the electrode terminal. The insertion portion is installed in a cylindrical shape. The closing portion is closed at the end facing the inside of the housing of the insertion portion to form a concave portion. The weak region is installed on the closing portion.

[0026] With the above method, the thickness of the occluded portion in the axial direction is relatively thin, so the vulnerable region is more sensitive to the internal pressure of the housing and is more likely to exhibit explosion-proof effects. Furthermore, it is permitted for gas inside the housing to enter the recess, pass through the recess, and be discharged.

[0027] In some embodiments, the occlusion is welded to the insertion portion, forming a weld mark, and the weak region is located within the weld mark.

[0028] The above method allows welding marks to be used as weak points, thereby simplifying the battery cell manufacturing process.

[0029] In some embodiments, the vulnerable region is arranged in a ring around the central axis of the pull-out hole.

[0030] With the above method, the vulnerable area is more sensitive to internal pressure in the housing, resulting in a better explosion-proof effect.

[0031] In some embodiments, the electrode terminals include an insertion portion and a closing portion connected to each other, the insertion portion being inserted into a pull-out hole along the axial direction of the electrode terminal, the insertion portion being cylindrically positioned, and the closing portion closing off the end of the insertion portion facing inward into the housing to form a recess, the battery cell including a closing member, the closing member being used to close the recess, and the battery cell being electrically connected to the outside via the closing member.

[0032] The above method allows for the connection area between the battery cell and the external device to be improved by closing the recess with a blocking member and electrically connecting it to the outside.

[0033] In some embodiments, the recess is used to inject electrolyte into the housing.

[0034] The above method simplifies the structural complexity of the battery cell, reduces the occurrence of electrolyte leakage during the assembly process, and improves the assembly efficiency of the battery cell.

[0035] In some embodiments, the occluded portion is provided with an injection hole, which connects the inside of the housing with the recess.

[0036] The above method is advantageous for sealing after the electrolyte injection is complete, thereby reducing the risk of electrolyte leakage.

[0037] In some embodiments, the battery cell further includes a current collector plate and an electrode assembly, which are installed inside the housing, and the current collector plate is used to connect the tabs of the electrode assembly to the electrode terminals, with the side away from the recess of the closure being welded to the current collector plate.

[0038] By using the above method, which takes advantage of the thin thickness of the closed section, the current collector plate is welded to the electrode terminal, making it easy to establish an electrical connection between the electrode terminal and the current collector plate from the side of the electrode terminal that is separated from the current collector plate.

[0039] In some embodiments, the battery cell includes an electrode assembly, the housing includes a case and an end cap, one end of the case has an opening, the end cap fits over the opening, the case includes a side wall and an end wall, the side wall surrounds the outside of the electrode assembly, the end wall is positioned opposite the opening, and the wall portion is the end cap or end wall.

[0040] By using the above method, the assembly efficiency of the battery cell can be improved by installing the electrode terminals on the end cap or end wall, and the possibility of deformation of the end cap or end wall can be reduced, thereby facilitating the assembly of the battery cell.

[0041] In some embodiments, the melting point of the electrode terminal material is lower than the melting point of the housing material.

[0042] When welding electrode terminals to other components using the above method, the relatively low melting point of the electrode terminal material is advantageous for reducing the welding temperature, while the relatively high melting point of the housing material reduces the adverse effects on the housing due to the welding process, thereby reducing the risk of leakage.

[0043] In some examples, the difference between the melting point of the housing material and the melting point of the electrode terminal material is greater than 300°C.

[0044] The above method is advantageous in reducing the welding temperature when welding electrode terminals to other components, and it can also reduce the adverse effects on the housing caused by the welding process, thereby reducing the risk of leakage.

[0045] In some embodiments, the housing material includes steel, and the electrode terminal material includes aluminum or copper.

[0046] With the above method, using steel as the housing material allows for a lower coefficient of thermal expansion and good mechanical strength in the housing. Since copper or aluminum has a lower melting point than steel, using copper or aluminum as the electrode terminal material makes welding of the electrode terminals easier and also facilitates the processing and shaping of copper or aluminum.

[0047] According to a second aspect, the present application provides a battery, the battery comprising the battery cell described above.

[0048] According to a third aspect, the present application provides a power consumption device, the power consumption device including the battery.

[0049] The above description is merely an outline of the proposed technology of this application. To make the technical means of this application easier to understand, and to make the other objectives, features, and advantages of this application clearer and easier to understand, the following will describe specific embodiments of this application in particular. The present invention provides, for example, the following items: (Item 1) It is a battery cell, The housing includes the wall portion where the drawer holes are installed, A battery cell characterized by including an electrode terminal provided in the aforementioned extraction hole and having a vulnerable region, wherein the vulnerable region is configured to break when the internal pressure or temperature of the housing exceeds a pressure threshold, thereby connecting the inside of the housing with the outside of the housing. (Item 2) The battery cell according to item 1, characterized in that the electrode terminal is provided with a notched groove, and the vulnerable region is formed at the bottom of the notched groove. (Item 3) The battery cell according to item 1, characterized in that the electrode terminal includes an insertion portion and a first flange portion connected to each other, the insertion portion is inserted into the pull-out hole along the axial direction of the electrode terminal, at least a portion of the outer circumferential surface of the first flange portion protrudes from the outer circumferential surface of the insertion portion in the radial direction of the electrode terminal, the portion of the first flange portion that is installed around the pull-out hole is supported on the side of the wall portion facing inward towards the housing, and the vulnerable region is installed on the insertion portion and / or the first flange portion. (Item 4) The battery cell according to item 3, characterized in that the electrode terminal is provided with a notched groove, the vulnerable region is formed at the bottom of the notched groove, and the notched groove is located on the side of the first flange portion toward and / or away from the wall portion. (Item 5) The battery cell according to item 4, characterized in that the notched groove is installed facing at least a portion of the alignment slit between the outer circumferential surface of the insertion portion and the hole wall of the extraction hole, along the axial direction. (Item 6) The battery cell according to item 5, characterized in that, in the radial direction, the radial width of the alignment slit is greater than the radial width of the notch groove. (Item 7) The battery cell according to item 6, characterized in that the projection of the outermost edge of the radially defined notch groove along the axial direction falls within the fitting slit. (Item 8) The battery cell according to item 7, characterized in that, in the radial direction, the radial width of the notch groove is 0.5 mm or more and 2 mm or less. (Item 9) The battery cell according to item 8, characterized in that, in the axial direction, the axial depth of the notch groove is 0.1 times or more the axial thickness of the first flange portion and 0.9 times or less the axial thickness of the first flange portion. (Item 10) The battery cell according to item 3, characterized in that at least a portion of the vulnerable area is located on the outer circumferential surface of the insertion portion. (Item 11) The battery cell according to item 1, characterized in that the electrode terminals include an insertion portion and a closing portion connected to each other, the insertion portion is inserted into the pull-out hole along the axial direction of the electrode terminals, the insertion portion is installed in a cylindrical shape, the closing portion closes the end of the insertion portion toward the inside of the housing to form a recess, and the vulnerable region is installed on the closing portion. (Item 12) The battery cell according to item 11, characterized in that the occluded portion is welded to the insertion portion and a weld mark is formed, and the weak region is located within the weld mark. (Item 13) The battery cell according to item 1, characterized in that the vulnerable region is arranged in a ring shape around the central axis of the extraction hole. (Item 14) The battery cell according to item 1, characterized in that the electrode terminal includes an insertion portion and a closing portion connected to each other, the insertion portion is inserted into the pull-out hole along the axial direction of the electrode terminal, the insertion portion is installed in a cylindrical shape, the closing portion closes the end of the insertion portion facing inward towards the housing to form a recess, the battery cell includes a closing member, the closing member is used to close the recess, and the battery cell is electrically connected to the outside via the closing member. (Item 15) The battery cell according to item 14, characterized in that the recess is used to inject an electrolyte into the housing. (Item 16) The battery cell according to item 15, characterized in that the closed portion is provided with an injection hole, and the injection hole communicates the inside of the housing with the recess. (Item 17) The battery cell according to item 14, further comprising a current collector plate and an electrode assembly installed inside the housing, wherein the current collector plate is used to connect the tabs of the electrode assembly to the electrode terminals, and the side of the closure away from the recess is welded to the current collector plate. (Item 18) The battery cell according to any one of items 1 to 17, wherein the battery cell includes an electrode assembly, the housing includes a case and an end cap, one end of the case has an opening, the end cap is fitted over the opening, the case includes a side wall and an end wall, the side wall surrounds the outside of the electrode assembly, the end wall is positioned opposite the opening, and the wall portion is the end cap or the end wall. (Item 19) The battery cell according to item 1, characterized in that the melting point of the material of the electrode terminal is smaller than the melting point of the material of the housing. (Item 20) The battery cell according to item 19, characterized in that the difference between the melting point of the housing material and the melting point of the electrode terminal material is greater than 300°C. (Item 21) The battery cell according to item 1, characterized in that the material of the housing includes steel, and the material of the electrode terminals includes aluminum or copper. (Item 22) A battery characterized by including a battery cell as described in any one of items 1 to 21. (Item 23) A power consumption device characterized by including the battery described in item 22. [Brief explanation of the drawing]

[0050] Various other advantages and benefits will become apparent to those skilled in the art by reading the detailed description of the preferred embodiments below. The drawings are for illustrative purposes only and should not be considered as limitations to this application. In all drawings, the same reference numerals represent the same components. In the drawings, [Figure 1] This is a schematic diagram of the structure of a vehicle according to one or more embodiments. [Figure 2] This is a schematic diagram of the disassembled structure of a battery according to one or more embodiments. [Figure 3] This is a schematic diagram of the cross-sectional structure of a battery cell according to one or more embodiments. [Figure 4] Figure 3 is a schematic cross-sectional view of the battery cell after concealing some of its components. [Figure 5] This is a schematic diagram of the bottom structure of a battery cell after concealing some of the components shown in Figure 3. [Figure 6] This is a schematic diagram of the structure of part A of the battery cell after some of the components shown in Figure 3 have been hidden. [Figure 7] This is a schematic diagram of the local structure of a battery cell according to one or more embodiments. [Figure 8] This is a schematic diagram of the local structure of a battery cell according to one or more embodiments. [Figure 9] This is a schematic diagram of the local structure of a battery cell according to one or more embodiments. [Figure 10]This is a schematic diagram of the local structure of a battery cell according to one or more embodiments. [Modes for carrying out the invention]

[0051] The following describes in detail embodiments of the technical proposal of this application, accompanied by drawings. The following embodiments are provided solely to clarify the technical proposal of this application and are merely examples; they do not limit the scope of protection of this application.

[0052] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by those skilled in the art relating to the present application. The terms used herein are solely for the purpose of describing specific embodiments and are not intended to limit this application. The terms “including” and “having” and any variations thereof in the description of the specification, claims, and drawings of this application are intentionally intended to cover the non-exclusive “including.”

[0053] In the descriptions of the embodiments of this application, technical terms such as "first," "second," etc., are used solely to distinguish different subjects and should not be understood as indicating or suggesting relative importance or the number, specific order, or hierarchical relationship of the technical features shown. In the descriptions of the embodiments of this application, unless otherwise explicitly and specifically limited, the meaning of "multiple" is two or more.

[0054] The “Examples” as used herein mean that certain features, structures, or characteristics described in conjunction with the Examples may be included in at least one Example of this Application. The appearance of this phrase at each location in the Specification does not necessarily refer to the same Example, nor does it mean that each Example is mutually exclusive or alternative to the others. Those skilled in the art will understand, both explicitly and implicitly, that the Examples described herein can be combined with other Examples.

[0055] In the description of the embodiments of this application, the term "and / or" merely describes a relationship between related objects, indicating that three relationships may exist. For example, A and / or B may represent three cases: A alone, a combination of A and B, or B alone. In this specification, the letter " / " generally indicates that the preceding and succeeding related objects are in an "or" relationship.

[0056] 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 sets (including two sets), and "multiple sheets" refers to two or more sheets (including two sheets).

[0057] In the description of the embodiments of this application, the orientations or positional relationships indicated by technical terms such as "center," "vertical direction," "horizontal direction," "length," "width," "thickness," "top," "bottom," "front," "back," "left," "right," "vertical," "horizontal," "top," "bottom," "inside," "outside," "clockwise," "counterclockwise," "axial direction," "radial direction," and "circumferential direction" are orientations or positional relationships shown based on the drawings and are solely for the purpose of facilitating the description of the embodiments of this application and for the simplification of the description. They do not indicate or imply that the mentioned devices or elements have a specific orientation or must be configured and operated in a specific orientation, and therefore should not be understood as limitations on the embodiments of this application.

[0058] In the description of the embodiments of this application, unless otherwise explicitly defined or limited, technical terms such as “attachment,” “connection,” “bonding,” and “fixing” should be understood in a broad sense. For example, these may be fixed connections, removable connections, integral connections, mechanical connections, electrical connections, direct connections, indirect connections via an intermediate medium, internal communication between two elements, or interaction relationships between two elements. Those skilled in the art will be able to understand the specific meaning of these terms in the embodiments of this application depending on the specific circumstances.

[0059] With advancements in battery technology, battery cells are being applied to an increasing number of fields, and are increasingly replacing conventional chemical petroleum energy in the automotive power sector. Battery cells can store chemical energy and controllably convert it into electrical energy. In recyclable battery cells, the active material can be reactivated through a charging method after discharge, allowing for continued use.

[0060] A battery cell often includes an electrode assembly, electrode terminals, and a housing. The electrode assembly is electrically connected to the outside via the electrode terminals. The housing can accommodate the electrode assembly and form a support for it. An electrolyte may be contained inside the housing, and the electrolyte and the active material on the electrode assembly can generate gas, increasing the internal pressure of the housing and posing a risk of the battery cell rupturing.

[0061] To reduce the risk of battery cell rupture, this application provides a vulnerable region on the electrode terminals, which is configured to connect the inside and outside of the housing when the internal pressure of the housing exceeds a pressure threshold or the temperature exceeds a temperature threshold. By placing the vulnerable region on the electrode terminals compared to placing it on the housing, the possibility of housing deformation is reduced, and the assembly of the battery cell can be facilitated.

[0062] Based on the above considerations, this application provides a battery cell, a battery and a power consumption device. After the pressure exceeds a pressure threshold or the temperature exceeds a temperature threshold, the electrode terminals can break or bend along the vulnerable region due to the action of pressure or high temperature, allowing excess gas inside the housing to be released, thereby reducing the risk of the battery cell rupturing due to excessively high internal pressure. By placing the vulnerable region on the insertion portion or the first flange portion, the vulnerable region can be made more sensitive to the internal pressure of the housing, making it easier to achieve explosion-proof effects. In this way, the risk of the battery cell rupturing can be reduced.

[0063] The battery cells, batteries, and power consumption devices disclosed in the embodiments of this application may be used in power consumption devices that use batteries as a power source or in various energy storage systems that use batteries as energy storage elements. Power consumption devices may include, but are not limited to, mobile phones, tablets, laptop computers, electric toys, power tools, battery-powered cars, electric vehicles, steamships, and aerospace aircraft. Here, electric toys may include stationary or portable electric toys, such as game consoles, electric car toys, electric steamship toys and electric airplane toys, and aerospace aircraft may include airplanes, rockets, space shuttles and spacecraft.

[0064] For the sake of explanation, the following embodiments will be described using the example that the power consumption device in one embodiment of this application is a vehicle 1000a.

[0065] Referring to Figure 1, the vehicle 1000a may be a fuel oil vehicle, a gas vehicle, or a new energy vehicle, and the new energy vehicle may be a pure electric vehicle, a hybrid vehicle, or a range extender vehicle. A battery 100a is installed inside the vehicle 1000a, and the battery 100a may be installed at the bottom, head, or tail of the vehicle 1000a. The battery 100a may be used to power the vehicle 1000a, for example, the battery 100a may be used as the operating power source for the vehicle 1000a. The vehicle 1000a may further include a controller 200a and a motor 300a, the controller 200a is used to control the battery 100a to power the motor 300a, for example, to meet the operating power consumption requirements of the vehicle 1000a during startup, navigation, and driving.

[0066] In some embodiments of this application, the battery 100a may be used not only as an operating power source for the vehicle 1000a, but also as a driving power source for the vehicle 1000a, providing driving power to the vehicle 1000a in place of or in place of fuel oil or natural gas.

[0067] In some embodiments, the battery 100a may be an energy storage device. The energy storage device includes an energy storage container, an energy storage electrical cabinet, and the like.

[0068] The battery 100a referred to in the embodiments of this application is a single physical module comprising one or more battery cells 1 to provide higher voltage and capacity.

[0069] In the embodiments of this application, the battery cell 1 may be a secondary battery, which is a battery cell that can be used continuously by activating the active material through a charging method after the battery cell has been discharged. Each battery cell 1 may also be a primary battery.

[0070] Battery cell 1 includes, but is not limited to, lithium-ion batteries, sodium-ion batteries, sodium-lithium-ion batteries, lithium metal batteries, sodium metal batteries, lithium-sulfur batteries, magnesium-ion batteries, nickel-metal hydride batteries, nickel-cadmium batteries, lead-acid batteries, etc. Battery cell 1 may have a cylindrical, flattened, rectangular parallelepiped, or other shape.

[0071] In some embodiments, the battery 100a may be a battery module, and if there are multiple battery cells 1, multiple battery cells 1 are arranged and fixed together to form a single battery module.

[0072] In some embodiments, referring to Figure 2, the battery 100a may be a battery pack, which includes a housing 10a and a battery cell 1, and the battery cell 1 or battery module is housed in the housing 10a.

[0073] In some embodiments, the housing 10a may be used as part of the chassis structure of the vehicle 1000a. For example, a portion of the housing 10a may be at least part of the floor of the vehicle 1000a, or a portion of the housing 10a may be at least part of the cross members and stringers of the vehicle 1000a.

[0074] Referring to Figure 2, the battery 100a includes a housing 10a and a battery cell 1, the battery cell 1 being housed within the housing 10a. Here, the housing 10a is used to provide a housing space for the battery cell 1, and the housing 10a may employ various structures. In some embodiments, the housing 10a may include a first part 11a and a second part 12a, the first part 11a and the second part 12a overlapping each other, and together they define a housing space for housing the battery cell 1. The second part 12a may be a hollow structure with one end open, and the first part 11a may be a plate-like structure. The first part 11a is placed over the open side of the second part 12a so that the first part 11a and the second part 12a jointly define a housing space. Both the first part 11a and the second part 12a may be hollow structures with one end open, and the open side of the first part 11a is placed over the open side of the second part 12a. Of course, the housing 10a formed from the first part 11a and the second part 12a may be of various shapes, such as a cylinder or a rectangular parallelepiped.

[0075] In battery 100a, there may be multiple battery cells 1, and the multiple battery cells 1 may be connected in series, in parallel, or in series-parallel. Series-parallel connection means that the multiple battery cells 1 have both series and parallel connections. Multiple battery cells 1 may be directly connected in series, in parallel, or in series-parallel, and the entire assembly composed of multiple battery cells 1 may be housed in the housing 10a. Of course, battery 100a may be configured as a battery module by first connecting multiple battery cells 1 in series, in parallel, or in series-parallel, and then multiple battery modules may be further connected in series, in parallel, or in series-parallel to form a single whole, which may be housed in the housing 10a. Battery 100a may further include other structures; for example, this battery 100a may further include busbar members for realizing electrical connections between multiple battery cells 1.

[0076] Referring to Figure 3, the battery cell 1 is the smallest unit that constitutes the battery 100a. In this embodiment, a cylindrical battery cell 1 is used as an example. The battery cell 1 includes a housing 100, an electrode assembly 500, and other functional components.

[0077] In some embodiments, the housing 100 is used to package components such as the electrode assembly 500 and the electrolyte. The housing 100 may be a steel case, an aluminum case, a plastic case (e.g., polypropylene), a composite metal case (e.g., a copper-aluminum composite housing), or an aluminum-plastic film.

[0078] The housing 100 may include an end cap 120 and a case 110. The end cap 120 is a component that fits over the opening 111 of the case 110 to isolate the internal environment of the battery cell 1 from the external environment. However, the shape of the end cap 120 may be adapted to the shape of the case 110 so as to fit into the case 110. Selectively, the end cap 120 may be made of a material having a certain hardness and strength (e.g., an aluminum alloy), so that the end cap 120 is less likely to deform when subjected to an extrusion impact, thereby giving the battery cell 1 higher structural strength and improving safety performance. Functional components such as electrode terminals 200 may be installed on the end cap 120. The electrode terminals 200 may be used for electrical connection with the electrode assembly 500 to output or input electrical energy from the battery cell 1. In some embodiments, a pressure relief mechanism may be further installed on the end cap 120 to release internal pressure when the internal pressure or temperature of the battery cell 1 reaches a threshold. The material of the end cap 120 may vary and may include, but is not limited to, copper, iron, aluminum, stainless steel, aluminum alloy, and plastic. In some embodiments, an insulating material member may be further installed inside the end cap 120, which may be used to isolate the end cap 120 from the electrical connection member in the case 110 and reduce the risk of short circuits. Exemplarily, the insulating material member may be plastic, rubber, or the like.

[0079] The case 110 is an assembly for fitting onto the end cap 120 to form the internal environment of the battery cell 1, where the formed internal environment may be used to house the electrode assembly 500, electrolyte, and other components. The case 110 and the end cap 120 may be independent components, or the internal environment of the battery cell 1 may be formed by placing an opening 111 on the case 110 and covering the opening 111 with the end cap 120. The end cap 120 and the case 110 may be integrated, and specifically, the end cap 120 and the case 110 may form a common connection surface before other components enter the case, and the end cap 120 may be placed over the case 110 when it is necessary to package the inside of the case 110. The case 110 may have various shapes and sizes, for example, a rectangular parallelepiped, cylindrical, or hexagonal prism shape. Specifically, the shape of the case 110 may be determined according to the specific shape and size of the electrode assembly 500. The material of case 110 may vary and may include, but is not limited to, copper, iron, aluminum, stainless steel, aluminum alloy, and plastic.

[0080] The electrode assembly 500 is a component in the battery cell 1 that generates an electrochemical reaction. The case 110 may contain one or more electrode assemblies 500.

[0081] In some embodiments, the electrode assembly 500 includes a positive electrode, a negative electrode, and a separator member. During the charging and discharging process of the battery cell, active ions (e.g., lithium ions) reciprocate between the positive and negative electrodes, intercepting and deintercepting them. The separator member is placed between the positive and negative electrodes and can prevent short circuits between the positive and negative electrodes, while also allowing active ions to pass through.

[0082] In some embodiments, the positive electrode may be a positive electrode plate, which may include a positive electrode current collector and a positive electrode active material placed on at least one surface of the positive electrode current collector.

[0083] For example, a positive electrode current collector has two opposing surfaces in the thickness direction of itself, and the positive electrode active material is placed on one or both of the two opposing surfaces of the positive electrode current collector.

[0084] For example, the positive electrode current collector may be a metal foil sheet or a composite current collector. For example, as the metal foil sheet, silver-surface-treated aluminum or stainless steel, stainless steel, copper, aluminum, carbon electrodes, carbon, nickel, or titanium may be used. The composite current collector may include a polymer material base layer and a metal layer. The composite current collector may be formed by forming a metal material (such as aluminum, aluminum alloy, nickel, nickel alloy, titanium, titanium alloy, silver, and silver alloy) on a polymer material substrate (for example, a substrate such as polypropylene, polyethylene terephthalate, polybutylene terephthalate, polystyrene, or polyethylene).

[0085] For example, the positive electrode active material may include at least one of the following materials: lithium-containing phosphate, lithium transition metal oxide, and their respective reformed compounds. However, this application is not limited to these materials, and other conventional materials that can be used as battery positive electrode active materials may also be used. These positive electrode active materials may be used individually or in combination of two or more. Here, examples of lithium-containing phosphates may include, but are not limited to, at least one of the following: lithium iron phosphate (e.g., LiFePO4 (which may be abbreviated as LFP)), composite materials of lithium iron phosphate and carbon, lithium manganese phosphate (e.g., LiMnPO4), composite materials of lithium manganese phosphate and carbon, lithium iron manganese phosphate, and composite materials of lithium iron manganese phosphate and carbon. Examples of lithium transition metal oxides include lithium cobalt oxide (e.g., LiCoO2), lithium nickel oxide (e.g., LiNiO2), lithium manganese oxide (e.g., LiMnO2, LiMn2O4), lithium nickel cobalt oxide, lithium manganese cobalt oxide, lithium nickel manganese oxide, and lithium nickel cobalt manganese oxide (e.g., LiNi 1 / 3 Co 1 / 3 Mn 1 / 3O2 (which may be abbreviated as NCM), LiNi 333 Co 0.5 Mn 0.2 O2 (which may be abbreviated as NCM), LiNi 0.3 Co 523 Mn 0.5 O2 (which may be abbreviated as NCM), LiNi 0.25 Co 0.25 Mn 211 O2 (which may be abbreviated as NCM), LiNi 0.6 Co 0.2 Mn 0.2 O2 (which may be abbreviated as NCM), LiNi 622 Co 0.8 Mn 0.1 O2 (which may be abbreviated as NCM), lithium nickel cobalt aluminum oxide (for example, LiNi 0.85 Co 0.15 Al 0.05 O2) and at least one of its modified compounds, etc., but not limited thereto.

[0086] In some embodiments, the negative electrode may be a negative electrode plate, and the negative electrode plate may include a negative electrode current collector.

[0087] As an example, the negative electrode current collector may employ a metal foil sheet, a metal foam, or a composite current collector. For example, as the metal foil sheet, aluminum or stainless steel with a silver surface treatment, stainless steel, copper, aluminum, a carbon electrode, carbon, nickel, or titanium, etc. may be employed. The metal foam may be a nickel foam, a copper foam, an aluminum foam, an alloy foam, or a carbon foam, etc. The composite current collector may include a polymer material-based layer and a metal layer. The composite current collector may be formed by forming a metal material (such as copper, copper alloy, nickel, nickel alloy, titanium, titanium alloy, silver, and silver alloy, etc.) on a polymer material substrate (such as substrates of polypropylene, polyethylene terephthalate, polybutylene terephthalate, polystyrene, polyethylene, etc.).

[0088] ​​​​For example, the negative electrode plate may include a negative electrode current collector and a negative electrode active material placed on at least one surface of the negative electrode current collector.

[0089] For example, the negative electrode current collector has two opposing surfaces in the thickness direction of itself, and the negative electrode active material is placed on one or both of the two opposing surfaces of the negative electrode current collector.

[0090] For example, the negative electrode active material may be a negative electrode active material known in the art for use in battery cells. For example, the negative electrode active material may include at least one of the following materials: artificial graphite, natural graphite, soft carbon, hard carbon, silicone-based materials, tin-based materials, and lithium titanate. The silicone-based material may be selected from at least one of elemental silicone, silicone oxide, silicone-carbon composite, silicone-nitrogen composite, and silicone alloy. The tin-based material may be selected from at least one of elemental tin, tin oxide, and tin alloy. However, this application is not limited to these materials, and conventional materials that can be used as negative electrode active materials in other batteries may also be used. These negative electrode active materials may be used individually or in combination of two or more.

[0091] In some embodiments, the material of the positive electrode current collector may be aluminum, and the material of the negative electrode current collector may be copper.

[0092] In some embodiments, the electrode assembly 500 further includes a separator member, which is placed between the positive electrode and the negative electrode.

[0093] In some embodiments, the separator member is a separator. This application does not particularly limit the type of separator, and any known porous separator having good chemical and mechanical stability may be selected.

[0094] For example, the main material of the separator may be selected from at least one of glass fiber, nonwoven fabric, polyethylene, polypropylene, polyvinylidene fluoride, and ceramics. The separator may be a single-layer film or a multilayer composite film, and there are no particular restrictions. When the separator is a multilayer composite film, the materials of each layer may be the same or different, and there are no particular restrictions. The separator member may be a single member positioned between the positive and negative electrodes, or it may be attached to the surfaces of the positive and negative electrodes.

[0095] In some embodiments, the separator member is a solid electrolyte. The solid electrolyte is placed between the positive and negative electrodes and serves to transmit ions and isolate the positive and negative electrodes.

[0096] In some embodiments, the battery cell further includes an electrolyte, which acts as a conductor of ions between the positive and negative electrodes. This application does not specifically limit the type of electrolyte, which can be selected according to the requirements. The electrolyte may be liquid, gel-like, or solid.

[0097] Here, the liquid electrolyte includes an electrolyte salt and a solvent.

[0098] In some embodiments, the electrolyte salt may be selected from at least one of lithium hexafluorophosphate, lithium tetrafluoroborate, lithium perchlorate, lithium hexafluoroarsenate, lithium bis(fluorosulfonyl)imide, lithium bis(trifluoromethanesulfonyl)imide, lithium trifluoromethanesulfonate, lithium difluorophosphate, lithium difluoro(oxalato)borate, lithium bis(oxalato)borate, lithium difluorobis(oxalato)phosphate, and lithium tetrafluoro(oxalato)phosphate.

[0099] In some embodiments, the solvent may be selected from at least one of ethylene carbonate, propylene carbonate, ethyl methyl carbonate, diethyl carbonate, dimethyl carbonate, dipropyl carbonate, methyl propyl carbonate, ethyl propyl carbonate, butylene carbonate, fluoroethylene carbonate, methyl formate, methyl acetate, ethyl acetate, propyl acetate, methyl propionate, ethyl propionate, propyl propionate, methyl butyrate, ethyl butyrate, 1,4-butyrolactone, sulfolane, dimethyl sulfone, ethyl methyl sulfone, and diethyl sulfone. The solvent may also be selected from ether-based solvents. The ether-based solvent may include one or more of ethylene glycol dimethyl ether, ethylene glycol diethyl ether, diethylene glycol dimethyl ether, triethylene glycol dimethyl ether, tetraethylene glycol dimethyl ether, 1,3-dioxolane, tetrahydrofuran, methyltetrahydrofuran, diphenyl ether, and crown ether.

[0100] Here, the gel-like electrolyte includes a combination of a polymer-based skeletal network and an ionic liquid-lithium salt.

[0101] Here, solid electrolytes include polymer solid electrolytes, inorganic solid electrolytes, and composite solid electrolytes.

[0102] For example, the polymer solid electrolyte may be polyether (polyoxyethylene), polysiloxane, polycarbonate, polyacrylonitrile, polyvinylidene fluoride, polymethyl methacrylate, monoionic polymer, polyionic liquid lithium salt, cellulose, etc.

[0103] For example, the inorganic solid electrolyte may be one or more of the following: oxide solid electrolytes (crystalline perovskite, sodium superconducting ion conductor, garnet, amorphous LiPON film), sulfide solid electrolytes (crystalline lithium superionic conductor (lithium germanium phosphate sulfur, silver germanite sulfide), amorphous sulfides), halide solid electrolytes, nitride solid electrolytes, and hydride solid electrolytes.

[0104] For example, composite solid electrolytes are formed by adding inorganic solid electrolyte fillers to a polymer solid electrolyte.

[0105] In some embodiments, the electrode assembly 500 is a wound structure. The positive electrode plate and the negative electrode plate are wound into the wound structure.

[0106] In some embodiments, the electrode assembly 500 is provided with tabs 501 from which current can be drawn from the electrode assembly 500. The tabs include a positive tab and a negative tab. The positive and negative electrode tabs may be located together at one end of the main body, or they may be located at opposite ends of the main body, respectively. During the charging and discharging process of the battery 100a, the positive electrode active material and the negative electrode active material react with the electrolyte, and the tabs 501 are connected to the electrode terminals to form a current circuit.

[0107] According to some embodiments of this application, as shown in Figures 3 to 5, the battery cell 1 of this application includes a housing 100 and electrode terminals 200. The housing 100 includes a wall portion 101, the wall portion 101 having an outlet hole 102. The electrode terminals 200 are provided in the outlet hole 102, and the electrode terminals 200 have a vulnerable region 211, which is configured to break when the internal pressure of the housing 100 exceeds a pressure threshold or the temperature exceeds a temperature threshold, thereby creating communication between the inside of the housing 100 and the outside of the housing 100.

[0108] The electrode terminal 200 can be attached to the housing 100 by inserting it into the pull-out hole 102. Specifically, one end of the electrode terminal 200 may be positioned facing inward into the housing 100 and used to electrically connect to the electrode assembly 500 installed inside the housing 100. The other end of the electrode terminal 200 may be positioned facing outward into the housing 100 and connected to the outside, thereby enabling charging and discharging of the electrode assembly 500.

[0109] The housing 100 can contain an electrolyte and an active material, which can generate gas and increase the internal pressure of the housing 100. If the gas continues to accumulate, the internal pressure of the housing 100 can be increased until it exceeds a pressure threshold. By placing a vulnerable region 211 on the electrode terminals 200, after the pressure exceeds the pressure threshold or the temperature exceeds the temperature threshold, the vulnerable region 211 is destroyed, creating communication between the inside and outside of the housing 100 and allowing the excess gas inside the housing 100 to be discharged.

[0110] If the energy release from battery cell 1 is too rapid, the temperature inside housing 100 often rises, and high temperatures can promote a rise in pressure. After the temperature exceeds the temperature threshold, the vulnerable region 211 can be destroyed, which is advantageous in mitigating the rise in pressure inside housing 100.

[0111] By installing it in this manner, the continuous rise in pressure inside the housing 100 can be suppressed, reducing the risk of the battery cell 1 rupturing.

[0112] Selectively, the vulnerable region 211 may be fractured by a pressure action greater than the load that the vulnerable region 211 can withstand. The vulnerable region 211 may also be fractured by a high-temperature action, for example, by reducing the strength of the vulnerable region 211 or by causing melting or deformation of the vulnerable region 211.

[0113] In some embodiments, the electrode terminal 200 may be completely fractured along the weak region 211, and the fractured portion may move away from the inside of the housing 100 due to the internal pressure action of the housing 100. In some other embodiments, the electrode terminal 200 may be partially fractured along the weak region 211, and the fractured portion may be bent away from the inside of the housing 100 due to the internal pressure action of the housing 100.

[0114] If the vulnerable area 211 is placed on the housing 100, for example on the wall portion 101, the structural strength of the housing 100 will be weakened, reducing its load-bearing capacity and making it more susceptible to deformation when subjected to force, which is disadvantageous for assembling the battery cell 1. For example, the housing 100 may also support the electrode assembly 500, and it would be inconvenient to assemble the electrode assembly 500 after the housing 100 has deformed. Therefore, by placing the vulnerable area 211 on the electrode terminals 200, the possibility of deformation of the housing 100 can be reduced, making it easier to assemble the battery cell 1.

[0115] According to some embodiments of this application, as selectively shown in Figure 6, the electrode terminal 200 is provided with a notched groove 210, and the vulnerable region 211 is formed at the bottom of the notched groove 210.

[0116] A vulnerable region 211 can be formed on the electrode terminal 200 by forming a notched groove 210. After the pressure exceeds a pressure threshold or the temperature exceeds a temperature threshold, the electrode terminal 200 can break or bend along the notched groove 210 due to the action of the pressure or high temperature, allowing excess gas inside the housing 100 to be released, thereby reducing the risk of the battery cell 1 rupturing due to excessively high internal pressure.

[0117] According to some embodiments of this application, selectively as shown in Figure 6, the electrode terminal 200 includes an insertion portion 220 and a first flange portion 230 connected to each other, the insertion portion 220 being inserted into a pull-out hole 102 along the axial direction of the electrode terminal 200, at least a portion of the outer circumferential surface of the first flange portion 230 protruding from the outer circumferential surface of the insertion portion 220, and the portion of the first flange portion 230 positioned around the pull-out hole 102 being supported on the side of the wall portion 101 facing inward into the housing 100, where the vulnerable region 211 is positioned on the insertion portion 220 and / or the first flange portion 230.

[0118] The axial direction of the electrode terminal 200 is the direction of the distance between the end of the electrode terminal 200 facing inward from the housing 100 and the end facing away from the housing 100, and the radial direction of the electrode terminal 200 is the direction perpendicular to the axial direction of the electrode terminal 200. Unless otherwise specified, the axial and radial directions below refer to the axial and radial directions of the electrode terminal 200.

[0119] The electrode terminal 200 can be mounted by positioning the insertion portion 220 so as to be inserted into the pull-out hole 102 along the axial direction of the electrode terminal 200. The connection stability between the electrode terminal 200 and the wall portion 101 can be improved by supporting the first flange portion 230 on the wall portion 101. In the radial direction of the electrode terminal 200, at least a portion of the outer circumferential surface of the first flange portion 230 protrudes from the outer circumferential surface of the insertion portion 220, and by installing the first flange portion 230 inside the housing 100, the wall portion 101 forms a barrier against the first flange portion 230, thereby preventing the electrode terminal 200 from detaching from inside the housing 100.

[0120] The vulnerable region 211 may be located on the insertion portion 220, on the first flange portion 230, or simultaneously on both the insertion portion 220 and the first flange portion 230. By location of the vulnerable region 211 on the insertion portion 220, when the internal pressure of the housing 100 exceeds a pressure threshold or the temperature exceeds a temperature threshold, the insertion portion 220 can rupture or bend along the vulnerable region 211, allowing excess gas from inside the housing 100 to be released. By location of the vulnerable region 211 on the first flange portion 230, when the internal drive of the housing 100 causes the pressure to exceed a pressure threshold or the temperature to exceed a temperature threshold, the first flange portion 230 can rupture or bend along the vulnerable region 211, allowing excess gas from inside the housing 100 to be released.

[0121] Because the pressure inside the housing 100 acts relatively strongly on the insertion portion 220 and the first flange portion 230, by placing the vulnerable region 211 on the insertion portion 220 or the first flange portion 230, the vulnerable region 211 can be made more sensitive to the pressure inside the housing 100, making it easier to achieve an explosion-proof effect.

[0122] According to some embodiments of this application, selectively as shown in Figures 6 to 8, the electrode terminal 200 is provided with a notched groove 210, the vulnerable region 211 is formed at the bottom of the notched groove 210, and the notched groove 210 is located on a side of the first flange portion 230 toward and / or away from the wall portion 101.

[0123] The side of the first flange portion 230 facing the wall portion 101 and the side of the first flange portion 230 away from the wall portion 101 may be distributed at intervals along the axial direction. The notch groove 210 may be installed on the side of the first flange portion 230 facing the wall portion 101, or on the side of the first flange portion 230 away from the wall portion 101, or on both sides of the first flange portion 230 facing the wall portion 101 and the side of the first flange portion 230 away from the wall portion 101 simultaneously. The weak region 211 may be formed by the notch groove 210.

[0124] By installing it in this manner, the machining of the notch groove 210 is facilitated, and because the thickness of the first flange portion 230 in the axial direction is generally relatively thin, the notch groove 210 is more sensitive to the internal pressure of the housing 100 and is more likely to exhibit an explosion-proof effect. When the internal pressure of the housing 100 exceeds the pressure threshold or the temperature exceeds the temperature threshold, the first flange portion 230 ruptures or bends along the notch groove 210 in the axial direction, thereby realizing the rupture prevention function of the notch groove 210.

[0125] Furthermore, in the radial direction, the first flange portion 230 and the insertion portion 220 are connected with a partial overlap, and the notch groove 210 may be installed in the non-overlapping portion between the first flange portion 230 and the insertion portion 220, which is advantageous for realizing the rupture prevention function of the notch groove 210.

[0126] According to some embodiments of this application, the notch groove 210 is optionally positioned facing at least a portion of the alignment slit 240 between the outer circumferential surface of the insertion portion 220 and the hole wall of the pull-out hole 102, as shown in Figure 6.

[0127] By aligning the notch groove 210 along the axial direction and positioning it opposite at least a portion of the slit 240, when the electrode terminal 200 breaks or bends along the notch groove 210, it can easily detach from the pull-out hole 102 without being blocked by the wall portion 101, allowing for rapid pressure release and thus enhancing the explosion-proof effect.

[0128] Furthermore, the battery cell 1 includes an insulating member 600, which is used to fill the mating slit 240 and can provide insulation and sealing effects. When the pressure inside the housing 100 exceeds a pressure threshold or the temperature exceeds a temperature threshold, the electrode terminals 200 can break or bend along the notched grooves 210, and the filling of the mating slit 240 by the insulating member 600 loosens, allowing gas to be released from the mating slit 240.

[0129] According to some embodiments of this application, selectively, as shown in Figure 6, the radial width D2 of the aligning slit 240 is greater than the radial width D1 of the notch groove 210 in the radial direction.

[0130] By setting the radial width D2 of the alignment slit 240 to be larger than the radial width D1 of the notch groove 210, the electrode terminal 200 can easily detach from the pull-out hole 102 when it breaks or bends along the notch groove 210, allowing for rapid pressure release and thus providing a more effective explosion-proof effect.

[0131] Specifically, when the internal pressure of the housing 100 exceeds a pressure threshold or the temperature exceeds a temperature threshold, the first flange portion 230 is divided along the notch groove 210 in the axial direction, forming a communication groove that penetrates the first flange portion 230. After the communication groove is formed, the gas accumulated inside the housing 100 can be discharged by passing through the communication groove and the slit 240 in sequence.

[0132] According to some embodiments of this application, selectively, as shown in Figure 6, the projection of the outermost radial edge of the notch groove 210 along the axial direction enters the mating slit 240.

[0133] In the radial direction, the notch groove 210 and the alignment slit 240 may partially overlap. When the internal pressure of the housing 100 exceeds a pressure threshold or the temperature exceeds a temperature threshold, the first flange portion 230 receives pressure, and the pressure acts on the housing 100 in a direction away from the inside of the housing 100, and deformation can occur at the bottom of the notch groove 210, causing the first flange portion 230 to break or bend along the notch groove 210.

[0134] By positioning the notch groove 210 such that the projection of its outermost radial edge along the axial direction falls within the alignment slit 240, the wall portion 101 can form a relief through the alignment slit 240 when the bottom of the notch groove 210 deforms. When the electrode terminal 200 breaks or bends along the notch groove 210, it becomes easier to detach from the pull-out hole 102, allowing for rapid pressure release and thus enhancing the explosion-proof effect.

[0135] Furthermore, the projection of the innermost edge of the notch groove 210 along the axial direction may be inside or outside the alignment slit 240.

[0136] According to some embodiments of this application, selectively, the radial width D1 of the notch groove 210 is 0.5 mm or more and 2 mm or less in the radial direction. For example, the radial width D1 of the notch groove 210 may be set to 0.6 mm, 0.8 mm, 1.0 mm, 1.4 mm, 1.6 mm, etc.

[0137] In the radial direction, setting the radial width D1 of the notch groove 210 to 0.5 mm or more is advantageous in promoting the first flange portion 230 to break or bend along the notch groove 210 when the internal pressure of the housing 100 exceeds a pressure threshold or the temperature exceeds a temperature threshold. By setting the radial width D1 of the notch groove 210 to 2 mm or less, the first flange portion 230 can maintain sufficient structural strength and improve the structural stability of the battery cell 1.

[0138] According to some embodiments of this application, selectively, in the axial direction, the axial depth H1 of the notch groove 210 is 0.1 times or more the axial thickness H0 of the first flange portion 230, and 0.9 times or less the axial thickness H0 of the first flange portion 230. For example, the axial depth H1 of the notch groove 210 may be equal to 0.1 times, 0.2 times, 0.3 times, 0.5 times, or 0.7 times the axial thickness H0 of the first flange portion 230. Also, for example, when the axial thickness H0 of the first flange portion 230 is equal to 1 mm, the radial width D1 of the notch groove 210 may be set to 0.2 mm, 0.4 mm, 0.5 mm, 0.6 mm, 0.8 mm, etc.

[0139] In the axial direction, setting the axial depth H1 of the notch groove 210 to 0.1 times the axial thickness H0 of the first flange portion 230 is advantageous in promoting the first flange portion 230 to break or bend along the notch groove 210 when the internal pressure of the housing 100 exceeds a pressure threshold or the temperature exceeds a temperature threshold. Setting the axial depth H1 of the notch groove 210 to 0.9 times or less the axial thickness H0 of the first flange portion 230 allows the first flange portion 230 to maintain sufficient structural strength, which is advantageous in improving the structural stability of the battery cell 1.

[0140] According to some embodiments of this application, selectively, as shown in Figure 9, at least a portion of the vulnerable region 211 is located on the outer circumferential surface of the insertion portion 220.

[0141] By installing it in this manner, the processing of the vulnerable region 211 is made easier, while the insertion portion 220 is more likely to form a fracture along the vulnerable region 211.

[0142] When the internal pressure of the housing 100 exceeds a pressure threshold or the temperature exceeds a temperature threshold, the insertion portion 220 can break or bend along the fragile region 211 from the outer surface, thereby reducing the risk of the battery cell 1 rupturing.

[0143] For example, the vulnerable region 211 may be formed at the bottom of the notch groove 210, the groove opening of the notch groove 210 may be opened on the outer circumferential surface of the insertion portion 220, the vulnerable region 211 may be located on the first flange portion 230, and the insertion portion 220 and the vulnerable region 211 may synchronously break or bend along the notch groove 210 when the internal pressure of the housing 100 exceeds a pressure threshold or the temperature exceeds a temperature threshold.

[0144] According to some embodiments of this application, selectively as shown in Figure 10, the electrode terminal 200 includes an insertion portion 220 and a closing portion 250 connected to each other, the insertion portion 220 being inserted into a pull-out hole 102 along the axial direction of the electrode terminal 200, the insertion portion 220 being cylindrically positioned, the closing portion 250 being closed to the end of the insertion portion 220 facing inward into the housing 100 to form a recess 260, and the vulnerable region 211 being positioned on the closing portion 250.

[0145] The recess 260 may be formed on the side of the closure portion 250 that is away from the inside of the housing 100. When the vulnerable region 211 is positioned on the side of the closure portion 250 facing the recess 260, it may communicate with the recess 260.

[0146] The vulnerable area 211 may be located on the side of the closure portion 250 facing the recess 260, on the side of the closure portion 250 away from the recess 260, or it may be located on both the side of the closure portion 250 facing the recess 260 and the side of the closure portion 250 away from the recess 260 simultaneously.

[0147] The side of the closure portion 250 facing the recess 260 and the side of the closure portion 250 moving away from the recess 260 may be spaced apart along the axial direction. By placing the vulnerable region 211 on the side of the closure portion 250 facing and / or moving away from the recess 260, when the internal pressure of the housing 100 exceeds a pressure threshold or the temperature exceeds a temperature threshold, the closure portion 250 can rupture or bend along the vulnerable region 211, allowing gas inside the housing 100 to enter the recess 260 and be discharged through the recess 260.

[0148] By providing the recess 260, the thickness of the closure portion 250 in the axial direction may be less than the thickness of the insertion portion 220. Because the thickness of the closure portion 250 in the axial direction is relatively thin, the vulnerable region 211 is more sensitive to the internal pressure of the housing 100 and is more likely to exhibit explosion-proof effects.

[0149] According to some embodiments of this application, selectively as shown in Figure 10, the closure portion 250 is welded to the insertion portion 220 and forms a weld mark 700, and the weak region 211 is located within the weld mark 700.

[0150] By controlling the welding process, the weld marks 700 can be utilized as a vulnerable region 211, and the vulnerable region 211 can be destroyed when the internal pressure of the housing 100 exceeds a pressure threshold or the temperature exceeds a temperature threshold. This configuration simplifies the manufacturing process of the battery cell 1.

[0151] In some embodiments, the battery cell 1 further includes a current collector plate 400 installed inside the housing 100. A weld joint 700 is formed after welding the closure portion 250 and the current collector plate 400, and the closure portion 250 and the current collector plate 400 are electrically connected through the weld joint 700. After the internal pressure of the housing 100 exceeds a pressure threshold or the temperature exceeds a temperature threshold, the closure portion 250 can break along a weak region 211, thereby blocking the current path between the electrode terminals 200 and the electrode assembly 500 and delaying the release of electrical energy.

[0152] In some other embodiments, the vulnerable region 211 is positioned on the closure 250 and surrounding the weld joint 700. This positioning allows the closure 250 to rupture along the vulnerable region 211 after the internal pressure of the housing 100 exceeds a pressure threshold or the temperature exceeds a temperature threshold, thereby blocking the current path between the electrode terminal 200 and the electrode assembly 500 and delaying the release of electrical energy.

[0153] According to some embodiments of this application, the vulnerable region 211 is optionally arranged in an annular manner around the central axis of the pull-out hole 102, as shown in Figure 5.

[0154] By installing it in this manner, the vulnerable region 211 is more sensitive to the internal pressure of the housing 100, and a better explosion-proof effect can be achieved. Specifically, after the internal pressure of the housing 100 exceeds the pressure threshold or the temperature exceeds the temperature threshold, the electrode terminal 200 can rupture along the vulnerable region 211. In the radial direction, the portion of the electrode terminal 200 located inside the vulnerable region 211 and the portion located outside the vulnerable region 211 may be separated from each other. Alternatively, the portion of the electrode terminal 200 located inside the vulnerable region 211 may be bent away from the inside of the housing 100.

[0155] According to some embodiments of this application, selectively as shown in Figures 3 and 6, the electrode terminal 200 includes an insertion portion 220 and a closing portion 250 connected to each other, the insertion portion 220 being inserted into a pull-out hole 102 along the axial direction of the electrode terminal 200, the insertion portion 220 being cylindrically positioned, and the closing portion 250 closing off the end of the insertion portion 220 facing inward into the housing 100 to form a recess 260, the battery cell 1 including a closing member 300, the closing member 300 being used to close off the recess 260, the battery cell 1 being electrically connected to the outside via the closing member 300.

[0156] By installing the blocking member 300 to block the recess 260, the blocking member 300 may be used to improve the connection area between the battery cell 1 and the external device and to mitigate electrolyte leakage from inside the battery cell 1.

[0157] Specifically, by installing the blocking member 300 and the electrode terminals 200 in a fixed connection, a current path can be formed between the electrode assembly 500, the electrode terminals 200, and the blocking member 300. The electrode assembly 500 may be electrically connected to the outside via the electrode terminals 200 and the blocking member 300 in order. For example, the battery cell 1 may be connected to a busbar via the blocking member 300. A busbar is a multi-layer composite connecting bar that can connect multiple battery cells 1 in series or parallel by welding or bolting.

[0158] Furthermore, a second flange portion 270 may be formed at the end of the electrode terminal 200 that moves away from the inside of the housing 100, the opening of the recess 260 may be located in the second flange portion 270, and the closing member 300 may be connected to the second flange portion 270 to close the recess 260, and the electrode terminal 200 may be electrically connected to the outside via the closing member 300. The wall portion 101 may act as a stopper between the first flange portion 230 and the second flange portion 270 to restrict the relative movement between the electrode terminal 200 and the housing 100.

[0159] According to some embodiments of this application, the recess 260 is selectively used to inject an electrolyte into the housing 100, as shown in Figure 3.

[0160] In the production process of the battery cell 1, the recess 260 can communicate with the inside of the housing 100, thereby allowing electrolyte to be injected into the housing 100 through the recess 260. By installing the recess 260, after assembling and connecting the electrode terminals 200 and the housing 100, the electrolyte can be injected using the recess 260 and then sealed using the sealing member 300, thereby simplifying the structural complexity of the battery cell 1, reducing the occurrence of electrolyte leakage during the assembly process, and improving the assembly efficiency of the battery cell 1.

[0161] According to some embodiments of this application, selectively, as shown in Figure 3, the occlusion portion 250 is provided with an injection hole 251, which connects the inside of the housing 100 with the recess 260.

[0162] During the assembly process of the battery cell 1, when injecting the electrolyte, the electrolyte can enter the housing 100 by passing through the recess 260 and the injection hole 251 in that order. The presence of the injection hole 251 is advantageous for sealing after the electrolyte injection is complete, thereby reducing the risk of electrolyte leakage. The closure portion 250 is thinner than the insertion portion 220, and by placing the injection hole 251 in the closure portion 250, it is advantageous for forming the injection hole 251, making it easier to inject the electrolyte.

[0163] Selectively, both ends of the injection hole 251 along the axial direction may communicate with the recess 260 and the interior of the housing 100, respectively.

[0164] When a vulnerable region 211 is provided in the occluded portion 250, the occlusion of the fluid injection hole 251 is configured so as not to be destroyed by pressure within a pressure threshold range or temperature within a temperature threshold range inside the housing 100, in order to realize the function of the vulnerable region 211. Of course, in some embodiments, the electrode terminal 200 does not need to have a fluid injection hole 251.

[0165] According to some embodiments of this application, selectively as shown in Figure 3, the battery cell 1 further includes a current collector plate 400 and an electrode assembly 500 installed inside a housing 100, the current collector plate 400 being used to connect the tabs 501 of the electrode assembly 500 to the electrode terminals 200, and the side away from the recess 260 of the closure portion 250 is welded to the current collector plate 400.

[0166] The current collector plate 400 may be installed between the electrode terminal 200 and the electrode assembly 500, and has the function of forming a current path between the electrode terminal 200 and the electrode assembly 500. By installing the current collector plate 400, electrical connection between the electrode terminal 200 and the electrode assembly 500 is easily achieved. By welding the current collector plate 400 to the closing portion 250, which has a thin thickness, electrical connection between the electrode terminal 200 and the current collector plate 400 is easily achieved from the side of the electrode terminal 200 that is away from the current collector plate 400.

[0167] According to some embodiments of this application, selectively as shown in Figure 3, the battery cell 1 includes an electrode assembly 500, and the housing 100 includes a case 110 and an end cap 120, one end of the case 110 having an opening 111, the end cap 120 fitting over the opening 111, the case 110 including a side wall 112 and an end wall 113, the side wall 112 surrounding the outside of the electrode assembly 500, the end wall 113 positioned opposite the opening 111, and the wall portion 101 is either the end cap 120 or the end wall 113.

[0168] In the above embodiment, the wall portion 101 is an end wall 113. In other embodiments, the wall portion 101 may be an end cap 120.

[0169] Since the end cap 120 or end wall 113 is flatter than the side wall 112, the assembly efficiency of the battery cell 1 can be improved by installing the electrode terminals 200 on the end cap 120 or end wall 113.

[0170] The electrode assembly 500 may be supported inside the housing 100 by an end cap 120 or end wall 113. If the vulnerable area 211 is placed on the end cap 120 or end wall 113, the structural strength of the end cap 120 or end wall 113 will be weakened, reducing its load-bearing capacity and making it more susceptible to deformation under force, which is detrimental to the progress of the battery cell assembly process. Therefore, by placing the vulnerable area 211 on the electrode terminal 200, the possibility of deformation of the end cap 120 or end wall 113 can be reduced, and the assembly of the battery cell 1 can be facilitated.

[0171] According to some embodiments of this application, selectively, the melting point of the material of the electrode terminal 200 is lower than the melting point of the material of the housing 100.

[0172] When welding the electrode terminal 200 to other components, the relatively low melting point of the electrode terminal 200 material is advantageous for reducing the welding temperature. However, the relatively high melting point of the housing 100 material reduces the risk of leakage by minimizing the adverse effects of the welding process on the housing 100.

[0173] According to some embodiments of this application, selectively, the difference between the melting point of the housing 100 material and the melting point of the electrode terminal 200 material is greater than 300°C.

[0174] By installing the device in this manner, it is advantageous to reduce the welding temperature when welding the electrode terminals 200 to other components, and the risk of leakage can be reduced by minimizing damage to the housing 100 during the welding process.

[0175] According to some embodiments of this application, the material of the housing 100 is optionally steel, and the material of the electrode terminals 200 is aluminum or copper.

[0176] By setting the material of the housing 100 to steel, the housing 100 can have a lower coefficient of thermal expansion and good mechanical strength. If the melting point of copper or aluminum is lower than that of steel, and the material of the electrode terminal 200 is copper or aluminum, welding of the electrode terminal 200 becomes easier, and the processing and forming of copper or aluminum becomes easier.

[0177] According to some embodiments of this application, selectively as shown in Figures 3 to 10, the battery cell 1 includes a housing 100 and electrode terminals 200. The housing 100 includes a wall portion 101, the wall portion 101 having an outlet hole 102. The electrode terminals 200 are provided in the outlet hole 102, and the electrode terminals 200 have a vulnerable region 211, which is configured to break when the internal pressure of the housing 100 exceeds a pressure threshold or the temperature exceeds a threshold, thereby connecting the inside of the housing 100 to the outside of the housing 100. The electrode terminals 200 are provided with a notched groove 210, and the vulnerable region 211 is formed at the bottom of the notched groove 210. The electrode terminal 200 includes an insertion portion 220 and a first flange portion 230 that are connected to each other, the insertion portion 220 being inserted into the pull-out hole 102 along the axial direction of the electrode terminal 200, at least a portion of the outer circumferential surface of the first flange portion 230 protruding from the outer circumferential surface of the insertion portion 220, and the portion of the first flange portion 230 positioned around the pull-out hole 102 being supported on the side of the wall portion 101 facing inward into the housing 100, where the vulnerable region 211 is located on the insertion portion 220 and / or the first flange portion 230. The electrode terminal 200 is provided with a notch groove 210, the vulnerable region 211 is formed at the bottom of the notch groove 210, and the notch groove 210 is located on the side of the first flange portion 230 facing and / or away from the wall portion 101. The notch groove 210 is positioned axially opposite at least a portion of the alignment slit 240 between the outer circumferential surface of the insertion portion 220 and the hole wall of the pull-out hole 102. In the radial direction, the radial width D2 of the alignment slit 240 is greater than the radial width D1 of the notch groove 210. The projection of the outermost radial edge of the notch groove 210 along the axial direction falls within the alignment slit 240. In the radial direction, the radial width D1 of the notch groove 210 is 0.5 mm or more and 2 mm or less. In the axial direction, the axial depth H1 of the notch groove 210 is 0.1 times or more the axial thickness H0 of the first flange portion 230 and 0.9 times or less the axial thickness H0 of the first flange portion 230. At least a portion of the vulnerable region 211 is located on the outer circumferential surface of the insertion portion 220.The electrode terminal 200 includes an insertion portion 220 and a closing portion 250 that are connected to each other. The insertion portion 220 is inserted into the extraction hole 102 along the axial direction of the electrode terminal 200 and is cylindrical in shape. The closing portion 250 closes off the end of the insertion portion 220 facing inward into the housing 100, forming a recess 260. The vulnerable region 211 is located on the closing portion 250. The closing portion 250 is welded to the insertion portion 220 and forms a weld mark 700, and the vulnerable region 211 is located within the weld mark 700. The vulnerable region 211 is installed in an annular shape around the central axis of the extraction hole 102. The electrode terminal 200 includes an insertion portion 220 and a closing portion 250 that are connected to each other. The insertion portion 220 is inserted into the pull-out hole 102 along the axial direction of the electrode terminal 200 and is cylindrical in shape. The closing portion 250 closes the end of the insertion portion 220 facing inward into the housing 100, forming a recess 260. The battery cell 1 includes a closing member 300, which is used to close the recess 260. The battery cell 1 is electrically connected to the outside via the closing member 300. The recess 260 is used to inject electrolyte into the housing 100. The closing portion 250 is provided with an injection hole 251, which connects the inside of the housing 100 to the recess 260. The battery cell 1 further includes a current collector plate 400 and an electrode assembly 500 installed inside the housing 100, the current collector plate 400 being used to connect the tabs 501 of the electrode assembly 500 to the electrode terminals 200, and the side away from the recess 260 of the closure portion 250 is welded to the current collector plate 400. The battery cell 1 includes the electrode assembly 500, the housing 100 includes a case 110 and an end cap 120, one end of the case 110 having an opening 111, the end cap 120 fitting over the opening 111, the case 110 including a side wall 112 and an end wall 113, the side wall 112 surrounding the outside of the electrode assembly 500, the end wall 113 being installed opposite the opening 111, and the wall portion 101 being either the end cap 120 or the end wall 113. The melting point of the material of the electrode terminal 200 is lower than the melting point of the material of the housing 100. The difference between the melting point of the material of the housing 100 and the melting point of the material of the electrode terminal 200 is greater than 300°C.The housing 100 is made of steel, and the electrode terminals 200 are made of aluminum or copper.

[0178] According to some embodiments of this application, as shown in Figure 2, the battery 100a includes the battery cell 1. By installing it in this manner, the risk of the housing 100 rupturing is reduced, thereby improving the stability and reliability of the battery cell 1 when it is operating, and further improving the stability and reliability of the battery 100a when it is operating.

[0179] According to some embodiments of this application, as shown in Figure 1, the power consumption device includes the battery 100a. By installing it in this manner, the stability and reliability of the battery 100a when it is operating can be improved by improving the stability and reliability of the battery cell 1 when it is operating, and further the stability and reliability of the power consumption device when it is operating can be improved.

[0180] In summary, the embodiment of this application allows the electrode terminal 200 to break or bend along the vulnerable region 211 due to the action of pressure after the pressure exceeds the pressure threshold or the temperature exceeds the temperature threshold, thereby enabling communication between the inside and outside of the housing 100, allowing excess gas inside the housing 100 to be discharged, reducing the risk of the battery cell 1 rupturing due to excessively high internal pressure, reducing the possibility of deformation of the housing 100, and facilitating the assembly of the battery cell 1.

[0181] Finally, it should be noted that the above embodiments are merely illustrative of the technical concepts of this application and do not limit them. While the application has been described in detail with reference to the above embodiments, those skilled in the art should understand that the technical concepts described in the above embodiments can still be modified, or some or all of their technical features can be replaced with equivalent ones. Such modifications or replacements should not deviate the essence of the relevant technical concept from the scope of the technical concepts in each embodiment of this application, and should all be included within the scope of the claims and specification of this application. In particular, unless there is a structural conflict, the technical features referred to in each embodiment may be combined in any manner. This application is not limited to the specific embodiments disclosed herein, but encompasses all technical concepts within the scope of the claims. [Explanation of Symbols]

[0182] The reference numerals in the drawings for embodiments of the invention are as follows: 1000a vehicle, 100A battery, 200A controller, 300A motor, 10a enclosure, 11a first part, 12a second part, D1 radial width of the notch groove, D2 radial width of the alignment slit, H0 axial thickness of the first flange portion, H1 axial depth of the notch groove, 1 Battery cell, 100 Housing, 101 Wall section, 102 Outlet hole, 200 Electrode terminal, 210 Notch groove, 211 Weak area, 220 Insertion section, 230 First flange section, 240 Alignment slit, 250 Closure section, 260 Recess, 270 Second flange section, 300 Closure member, 251 Injection hole, 400 Current collector plate, 500 Electrode assembly, 501 Tab, 110 Case, 120 End cap, 111 Opening, 112 Side wall, 113 End wall, 600 Insulating member, 700 Weld mark.

Claims

1. It is a battery cell, The housing includes the wall portion where the drawer holes are installed, An electrode terminal provided in the aforementioned extraction hole and having a vulnerable region installed, wherein the vulnerable region is configured to break when the internal pressure of the housing exceeds a pressure threshold or the temperature exceeds a temperature threshold, thereby creating communication between the inside of the housing and the outside of the housing, The electrode terminal includes an insertion portion and a closing portion connected to each other, the insertion portion is inserted into the pull-out hole along the axial direction of the electrode terminal, the insertion portion is installed in a cylindrical shape, the closing portion closes the end of the insertion portion toward the inside of the housing to form a recess, and the vulnerable region is installed on the closing portion. The battery cell is characterized in that the occluded portion is welded to the insertion portion and a weld mark is formed, and the weak region is located within the weld mark.

2. The battery cell according to claim 1, characterized in that the electrode terminal is provided with a notched groove, and the vulnerable region is formed at the bottom of the notched groove.

3. The battery cell according to claim 1, wherein the electrode terminal includes an insertion portion and a first flange portion connected to each other, the insertion portion is inserted into the pull-out hole along the axial direction of the electrode terminal, at least a portion of the outer circumferential surface of the first flange portion protrudes from the outer circumferential surface of the insertion portion in the radial direction of the electrode terminal, and the portion of the first flange portion installed around the pull-out hole is supported on the side of the wall portion facing inward towards the housing, wherein the vulnerable region is installed on the insertion portion and / or the first flange portion.

4. The battery cell according to claim 3, characterized in that the electrode terminal is provided with a notched groove, the vulnerable region is formed at the bottom of the notched groove, and the notched groove is located on the side of the first flange portion toward and / or away from the wall portion.

5. The battery cell according to claim 4, characterized in that the notched groove is installed facing at least a portion of the alignment slit between the outer circumferential surface of the insertion portion and the hole wall of the extraction hole, along the axial direction.

6. The battery cell according to claim 5, characterized in that, in the radial direction, the radial width of the alignment slit is greater than the radial width of the notch groove.

7. The battery cell according to claim 6, characterized in that the projection of the outermost edge of the radial notch groove along the axial direction falls within the fitting slit.

8. The battery cell according to claim 7, characterized in that, in the radial direction, the radial width of the notch groove is 0.5 mm or more and 2 mm or less.

9. The battery cell according to claim 8, characterized in that, in the axial direction, the axial depth of the notch groove is 0.1 times or more the axial thickness of the first flange portion and 0.9 times or less the axial thickness of the first flange portion.

10. The battery cell according to claim 3, characterized in that at least a portion of the vulnerable region is located on the outer circumferential surface of the insertion portion.

11. The battery cell according to claim 1, characterized in that the vulnerable region is arranged in a ring shape around the central axis of the extraction hole.

12. The battery cell according to claim 1, wherein the battery cell includes a blocking member, the blocking member is used to block the recess, and the battery cell is electrically connected to the outside via the blocking member.

13. The battery cell according to claim 12, characterized in that the recess is used to inject an electrolyte into the housing.

14. The battery cell according to claim 13, characterized in that an injection hole is provided in the closed portion, and the injection hole communicates the inside of the housing with the recess.

15. The battery cell according to claim 12, further comprising a current collector plate and an electrode assembly installed inside the housing, wherein the current collector plate is used to connect the tabs of the electrode assembly to the electrode terminals, and the side of the closure away from the recess is welded to the current collector plate.

16. The battery cell according to claim 1, wherein the battery cell includes an electrode assembly, the housing includes a case and an end cap, one end of the case has an opening, the end cap is fitted over the opening, the case includes a side wall and an end wall, the side wall surrounds the outside of the electrode assembly, the end wall is installed opposite the opening, and the wall portion is the end cap or the end wall.

17. The battery cell according to claim 1, characterized in that the melting point of the material of the electrode terminal is smaller than the melting point of the material of the housing.

18. The battery cell according to claim 17, characterized in that the difference between the melting point of the housing material and the melting point of the electrode terminal material is greater than 300°C.

19. The battery cell according to claim 1, characterized in that the material of the housing includes steel, and the material of the electrode terminals includes aluminum or copper.

20. A battery characterized by including a battery cell according to any one of claims 1 to 19.

21. A power consumption device characterized by including the battery described in claim 20.

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