Battery cell, battery device and electric device

Abstract

The utility model discloses a battery monomer, battery device and power utilization device, battery monomer includes: shell, electrode subassembly, relief valve and bottom support plate, the shell is equipped with the accommodation cavity, shell includes the mounting wall that participates in defining the accommodation cavity, the electrode subassembly is provided in the accommodation cavity, the relief valve is provided on the mounting wall, the bottom support plate is provided in the accommodation cavity, the bottom supporting plate is located between the electrode assembly and the mounting wall, the bottom supporting plate comprises a plate body part and at least one protruding part, the protruding part is arranged on the surface of the side, facing the mounting wall, of the plate body part in a protruding mode, and the protruding part and the pressure release valve are arranged in a staggered mode, so that a channel penetrating through the two length ends of the bottom supporting plate is defined by the bottom supporting plate and communicates with the pressure release valve; a plurality of first capillary holes through which electrolyte can permeate are formed in the bottom supporting plate, and the first capillary holes penetrate through the plate body part and the protruding part in the thickness direction of the plate body part. Therefore, the electrolyte can effectively infiltrate the electrode assembly through the plurality of first capillary pores, and a discharge space can be conveniently provided for the pressure release valve.

Description

Technical Field

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

[0002] With current social development and technological advancements, battery cells are widely used as power sources for portable electronic products such as mobile communications devices, laptops, and digital cameras, as well as energy storage systems for electric vehicles. The lifespan of battery cells is a key concern. As battery cells are used for extended periods, the electrolyte is continuously consumed. To ensure the charge-discharge cycle efficiency of the battery cell, electrolyte is added inside the cell's casing. Under the influence of gravity, some electrolyte adheres to the electrode assembly, while the remaining electrolyte remains at the bottom of the casing.

[0003] However, when the electrode assembly needs to be re-immersed in the electrolyte, the electrolyte remaining at the bottom of the casing cannot fully wet the electrode assembly, resulting in a decrease in the cycle performance of the battery cell and thus a reduction in the battery cell's lifespan. Utility Model Content

[0004] This application proposes a battery cell, a battery device, and an electrical device. The first capillary hole, which penetrates the plate body and the protrusion, facilitates the delivery of electrolyte stored at the bottom of the casing to the electrode assembly, thereby improving the wetting effect of the electrode assembly. The bottom support plate has a channel that penetrates both ends of the bottom support plate, which facilitates the provision of discharge space for the pressure relief valve.

[0005] In a first aspect, embodiments of this application provide a battery cell, including: a housing, an electrode assembly, a pressure relief valve, and a base plate. The housing has a receiving cavity and includes a mounting wall that defines the receiving cavity. The electrode assembly is disposed in the receiving cavity, the pressure relief valve is disposed in the mounting wall, and the base plate is disposed in the receiving cavity and located between the electrode assembly and the mounting wall. The base plate includes a plate body and at least one protrusion. The protrusion protrudes from the side surface of the plate body facing the mounting wall and is offset from the pressure relief valve, so that the base plate defines a channel penetrating both ends of the length of the base plate. The channel communicates with the pressure relief valve. A plurality of first capillary pores capable of allowing electrolyte permeation are formed on the base plate. The first capillary pores penetrate the plate body and the protrusion along the thickness direction of the plate body.

[0006] In the above technical solution, the first capillary pore penetrates the plate body and the protrusion along the thickness direction of the plate body. The bottom support plate is located between the electrode assembly and the mounting wall. The electrolyte remaining on the side of the bottom support plate facing the mounting wall can easily pass through multiple capillary pores and be transported to the electrode assembly under the action of capillary action. This allows the electrolyte remaining on the side of the bottom support plate facing the mounting wall to be fully utilized, and the electrode assembly can be fully wetted by the electrolyte, which is conducive to improving the cycle performance of the battery cell. The protrusion is protruding from the surface of the plate body facing the mounting wall, so that the bottom support plate defines a channel penetrating both ends of the length of the bottom support plate. When the battery cell experiences thermal runaway, it is convenient to provide venting space for the pressure relief valve, which is beneficial to improving the reliability of the battery cell.

[0007] In some embodiments, there are multiple protrusions, which are spaced apart along the length and / or width direction of the plate body.

[0008] In the above technical solution, multiple protrusions are spaced apart along the length and / or width of the plate body, which facilitates increasing the support range of the multiple protrusions and makes the electrode assembly placed on the base plate more stable.

[0009] In some embodiments, the protrusion extends in a long strip shape along the length or width direction of the plate body.

[0010] In the above technical solution, the protrusion extends into a long strip along the length or width of the plate body, which makes it easier to increase the support area of ​​the protrusion, and the bottom support plate structure is relatively simple and easy to process.

[0011] In some embodiments, the base plate is configured to satisfy at least one of the following conditions: Condition A1, the base plate is a one-piece molded part, and is a polypropylene part, a polyethylene part, a polyethylene terephthalate part, or a polyimide part; Condition A2, the thickness t1 of the plate body portion satisfies 0.3mm≤t1≤0.8mm; Condition A3, the pore diameter d of the first capillary pore satisfies 0.01mm≤d≤1mm; Condition A4, the thickness t2 of the protrusion portion satisfies 0.2mm≤t2≤5mm; Condition A5, the thickness of the protrusion portion is greater than the thickness of the plate body portion.

[0012] In the above technical solution, condition A1, the base plate is an integrally molded part, which is convenient for processing and manufacturing, and the base plate is made of polypropylene, polyethylene, polyethylene terephthalate, or polyimide, which helps to improve the service life of the base plate; condition A2, the thickness t1 of the plate body satisfies 0.3mm≤t1≤0.8mm. By setting the thickness of the plate body in the range of 0.3mm to 0.8mm, the plate body can provide sufficient structural strength to support the electrode assembly, while maintaining a relatively light weight; condition A3, the pore diameter d of the first capillary pore satisfies 0.01mm≤d≤1mm. By setting the pore diameter d of the first capillary pore within the range of 0.01 mm to 1 mm, an appropriate pore diameter can enhance the capillary effect, making it easier for the electrolyte to be transported to the electrode assembly; Condition A4, the thickness t2 of the protrusion satisfies 0.2 mm ≤ t2 ≤ 5 mm. By setting the thickness of the protrusion within the range of 0.2 mm to 5 mm, the protrusion can provide sufficient structural strength to support the electrode assembly without excessively affecting the energy density of the battery cell; Condition A5, the thickness of the protrusion is greater than the thickness of the plate, providing more space for storing the electrolyte inside the casing.

[0013] In some embodiments, the base plate satisfies condition A3, 0.1mm≤d≤0.5mm.

[0014] In the above technical solution, by setting the pore size of the first capillary pore in the range of 0.1mm to 0.5mm, the smaller pore size can enhance the capillary effect, making it easier for the electrolyte to be transferred to the electrode assembly.

[0015] In some embodiments, the size of the protrusion is smaller than the width of the plate portion in the width direction.

[0016] In the above technical solution, the size of the protrusion is smaller than the width of the plate body. Therefore, the protrusion will not completely block the flow of electrolyte in the width direction of the bottom support plate. That is, the electrolyte can be distributed more evenly in the area formed by the bottom support plate and the shell.

[0017] In some embodiments, the plurality of protrusions include a first protrusion and a plurality of second protrusions, the plurality of second protrusions being spaced apart along the length direction of the plate portion, and the plurality of second protrusions having at least one first protrusion spaced apart on both sides of the plate portion in the width direction, the first protrusions extending along the length direction of the plate portion, and the length of the first protrusions being greater than or equal to half the length of the plate portion.

[0018] In the above technical solution, the second protrusions are spaced apart along the length of the plate body. The multiple second protrusions are spaced apart on both sides of the width of the plate body by at least one first protrusion. This makes the distribution of the multiple protrusions on the plate body more uniform, so that the protrusions have a more stable support effect. Moreover, the uniformly distributed protrusions have a better wetting effect on the electrode assembly. The length of the first protrusion is greater than or equal to half the length of the plate body, so that the bottom plate can have more first capillaries, which facilitates the improvement of the wetting effect of the electrolyte on the electrode assembly.

[0019] In some embodiments, the two outermost protrusions of the plurality of second protrusions extend to be flush with the length end of the plate portion, and the two ends of the length of the first protrusion extend to be flush with the corresponding length ends of the plate portion.

[0020] In the above technical solution, the two outermost protrusions of the plurality of second protrusions extend to be flush with the length end of the plate body, and the two ends of the length of the first protrusion extend to be flush with the corresponding length ends of the plate body, which facilitates the improvement of the support effect of the protrusions and facilitates the setting of more first capillary pores on the base plate to enhance the wetting effect of the electrolyte on the electrode assembly.

[0021] In some embodiments, the thickness t2 of the protrusion satisfies 0.6mm≤t2≤5mm.

[0022] In the above technical solution, by setting the thickness t2 of the protrusion in the range of 0.6mm to 5mm, the protrusion can provide sufficient structural strength to support the electrode assembly, while the protrusion will not occupy too much space in the housing, which is conducive to improving the energy density of the battery cell.

[0023] In some embodiments, 1mm ≤ t2 ≤ 3mm.

[0024] In the above technical solution, by limiting the thickness of the protrusion to the range of 1mm to 3mm, it is easier to better match the setting of the first protrusion and the second protrusion on the base plate, so that the protrusion has a good support effect and is convenient for the processing and manufacturing of the base plate.

[0025] In some embodiments, a plurality of protrusions spaced apart along the length of the plate portion are configured as protrusion groups. There are multiple protrusion groups and they are spaced apart along the width of the plate portion. The protrusions of two adjacent protrusion groups are positioned facing each other along the width of the plate portion.

[0026] In the above technical solution, the protrusions of multiple sets of protrusions are arranged facing each other along the width direction of the plate body, so that the distribution of the protrusions on the bottom support plate is more uniform, making the support provided by the protrusions more stable, and the structure is simpler and easier to process and manufacture.

[0027] In some embodiments, the thickness t2 of the protrusion satisfies 0.2mm≤t2≤3mm.

[0028] In the above technical solution, by setting the thickness t2 of the protrusion in the range of 0.2mm to 3mm, the protrusion can provide sufficient structural strength to support the electrode assembly, while the protrusion will not occupy too much space in the housing, which is conducive to improving the energy density of the battery cell.

[0029] In some embodiments, 1mm ≤ t2 ≤ 2mm.

[0030] In the above technical solution, by limiting the thickness of the protrusion to the range of 1mm to 2mm, it is easier to match the setting of multiple protrusion groups on the base plate, so that the protrusion has a good support effect and is convenient for the processing and manufacturing of the base plate.

[0031] In some embodiments, the pressure relief valve is located at the middle of the mounting wall in the length direction, and the channel includes a first channel segment and a second channel segment that are connected along the length direction of the plate body. The flow area of ​​at least a portion of at least one of the first channel segment and the second channel segment decreases along the length direction of the plate body towards the center position of the plate body in the length direction.

[0032] In the above technical solution, at least a portion of the flow area of ​​at least one of the first channel segment and the second channel segment decreases along the length direction of the plate towards the center position of the plate portion in the length direction. This allows the electrolyte to be distributed more evenly in the channel formed by the plate portion and the protrusion, which is conducive to improving the wetting effect of the electrolyte on the electrode assembly and to improving the pressure relief rate of the battery cell.

[0033] In some embodiments, the plurality of protrusions include a third protrusion and a fourth protrusion spaced apart along the width direction of the plate portion, a channel is formed between the third protrusion and the fourth protrusion, and at least one of the third protrusion and the fourth protrusion protrudes towards the center of one side surface of the other, near the center of the plate portion.

[0034] In the above technical solution, at least one of the third protrusion and the fourth protrusion protrudes from the middle of one side surface facing the other toward the center of the plate body, so that the third protrusion and / or the fourth protrusion form an arch-like structure, which facilitates more effective stress distribution when the bottom plate is subjected to external force.

[0035] In some embodiments, a plurality of spaced positioning holes are formed on the base plate, the positioning holes corresponding to the protrusions or avoiding the protrusions, and the opening area of ​​the positioning holes is larger than the opening area of ​​the first capillary.

[0036] In the above technical solution, the base plate has multiple spaced positioning holes, which facilitates the positioning and installation of the base plate. The positioning holes correspond to the protrusions, which helps to reduce the amount of material used in manufacturing the base plate. Alternatively, the positioning holes and the protrusions are set to avoid forming weak areas on the protrusions, which helps to improve the support effect of the protrusions. The opening area of ​​the positioning holes is larger than the opening area of ​​the first capillary hole, which makes it easy to distinguish between the positioning holes and the first capillary hole, and facilitates the installation of the base plate.

[0037] In some embodiments, the positioning hole is located in the middle of the base plate in its width direction, and all the protrusions are symmetrically arranged about the center line of the base plate, the center line extending along the length direction of the plate body.

[0038] In the above technical solution, the positioning hole is located in the middle of the base plate in the width direction, which provides a clear reference point for positioning during the installation process of the base plate and facilitates the installation of the base plate. All the protrusions are symmetrically arranged about the center line of the base plate, which makes the distribution of the protrusions on the base plate more uniform and facilitates the improvement of the support stability of multiple protrusions.

[0039] In some embodiments, the battery cell further includes an insulating film disposed within a receiving cavity and covering an electrode assembly. The insulating film is connected to a base plate, and a second capillary pore is formed on the portion of the insulating film disposed between the electrode assembly and the base plate, allowing electrolyte to permeate.

[0040] In the above technical solution, the protrusion is located on the side of the plate body away from the electrode assembly. The empty space formed by the protrusion and the shell facilitates an increase in the electrolyte storage capacity inside the shell. The pressure relief valve is located on the shell and on the side of the bottom support plate away from the electrode assembly. The empty space formed by the bottom support plate and the shell provides venting space for the pressure relief valve, which helps improve the reliability of the battery cell. The insulating film covers the electrode assembly and is connected to the bottom support plate. The insulating film can effectively isolate the electrical contact between the electrode assembly and the shell, thereby reducing the possibility of the shell becoming charged. The insulating film has second capillary pores that allow electrolyte penetration. Through the cooperation of the first capillary pores and the second capillary pores, the electrolyte can be better transported to the electrode assembly, which helps improve the cycle performance of the battery cell. Therefore, by adopting the bottom support plate of the battery cell described above, the stability of the battery cell is improved, and the electrolyte can effectively wet the electrode assembly through multiple first capillary pores, effectively improving the cycle performance of the battery cell.

[0041] Secondly, embodiments of this application provide a battery device including a plurality of battery cells according to the second aspect.

[0042] In the above technical solution, the battery device includes multiple battery cells, which possess good stability and cycle performance. This facilitates improvements in the stability and lifespan of the battery device.

[0043] Thirdly, embodiments of this application provide an electrical device, including a battery device as described in the third aspect, the battery device being used to provide electrical energy.

[0044] In the above technical solution, the electrical device includes a battery device, which provides electrical energy and has good stability and service life. Therefore, the battery device provides electrical energy more stably, which helps improve the stability of the electrical device during operation. Attached Figure Description

[0045] The above and / or additional aspects and advantages of this utility model will become apparent and readily understood from the description of the embodiments taken in conjunction with the following drawings, in which:

[0046] Figure 1 This is a schematic diagram of the electrical device proposed in an embodiment of the present utility model;

[0047] Figure 2 for Figure 1 A schematic diagram of the battery device shown;

[0048] Figure 3 This is a schematic diagram of a battery cell proposed in an embodiment of the present utility model;

[0049] Figure 4 for Figure 3 A schematic diagram of the base plate shown;

[0050] Figure 5 for Figure 4 A magnified view of point A, indicated by the center circle;

[0051] Figure 6 for Figure 4 Another schematic diagram of the base plate shown;

[0052] Figure 7 for Figure 6 A magnified view of point B, indicated by the center circle;

[0053] Figure 8 for Figure 3 Another schematic diagram of the base plate shown;

[0054] Figure 9 for Figure 8 Another schematic diagram of the base plate shown;

[0055] Figure 10 for Figure 8 Another schematic diagram of the base plate shown;

[0056] Figure 11 for Figure 3 Another schematic diagram of the base plate shown;

[0057] Figure 12 for Figure 11 A magnified view of point C, indicated by the center circle;

[0058] Figure 13 This is a schematic diagram of the electrode assembly and the insulating film;

[0059] Figure 14 for Figure 13 A schematic diagram of the insulating film is shown.

[0060] Reference numerals: Electrical device 4, Battery device 3, Battery cell 2, Base plate 1, Plate body 10, Protrusion 20, First protrusion 22, Second protrusion 23, Protrusion group 25, Channel 26, First channel segment 260, Second channel segment 262, First connecting port 264, Second connecting port 266, Third protrusion 27, Fourth protrusion 28, Fifth protrusion 29, First capillary 30, Positioning hole 40, Electrode assembly 52, Insulating film 54, Second capillary 540, Controller 60, Motor 62, Housing 70, First housing 72, Second housing 74, Shell 80, Receiving cavity 82, Mounting wall 84, Pressure relief valve 90. Detailed Implementation

[0061] To make the objectives, technical solutions, and advantages of the embodiments of this application clearer, the technical solutions of the embodiments of this application will be clearly described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0062] Unless otherwise defined, all technical and scientific terms used in this application have the same meaning as commonly understood by one of ordinary skill in the art to which this application pertains; the terminology used in the description of this application is for the purpose of describing particular embodiments only and is not intended to limit the application; the terms "comprising" and "having," and any variations thereof, in the description, claims, and accompanying drawings of this application are intended to cover non-exclusive inclusion. The terms "first," "second," etc., in the description, claims, or accompanying drawings of this application are used to distinguish different objects, not to describe a specific order or hierarchy.

[0063] In this application, the reference to "embodiment" means that a particular feature, structure, or characteristic described in connection with an embodiment may be included in at least one embodiment of this application. The appearance of this phrase in various places in the specification does not necessarily refer to the same embodiment, nor is it a separate or alternative embodiment that is mutually exclusive with other embodiments.

[0064] In the description of this application, it should be noted that, unless otherwise expressly specified and limited, the terms "installation," "connection," "linking," and "attachment" should be interpreted broadly. For example, they can refer to direct connection or indirect connection through an intermediate medium. Those skilled in the art can understand the specific meaning of the above terms in this application according to the specific circumstances.

[0065] In this application, the term "and / or" is merely a description of the relationship between related objects, indicating that three relationships can exist. For example, A and / or B can represent: A existing alone, A and B existing simultaneously, or B existing alone. Additionally, in this application, the character " / " generally indicates that the preceding and following related objects have an "or" relationship.

[0066] In the embodiments of this application, the same reference numerals denote the same components, and for the sake of brevity, detailed descriptions of the same components are omitted in different embodiments. It should be understood that the dimensions of the various components shown in the accompanying drawings in the embodiments of this application are merely illustrative and should not constitute any limitation on this application.

[0067] In this application, "multiple" means two or more (including two).

[0068] The battery device mentioned in the embodiments of this application refers to a single physical module comprising one or more battery cells to provide higher voltage and capacity. Multiple battery cells in the battery device can be connected in series, parallel, or mixed via a busbar. For example, the battery device mentioned in this application can be a battery module or a battery pack. A battery module is formed by arranging and fixing multiple battery cells to form an independent module. As an example, a battery module can be formed by bundling multiple battery cells together with cable ties. A battery pack generally includes a housing for encapsulating one or more battery cells or one or more battery modules. The housing can prevent liquids or other foreign objects from affecting the charging or discharging of the battery cells. Of course, the battery device may also not include a housing.

[0069] As an example, the battery device is housed in the housing by fixing battery modules within the housing. Alternatively, the battery device can be housed in the housing by directly fixing multiple individual battery cells to the housing.

[0070] As an example, the enclosure may include a first enclosure and a second enclosure. The first enclosure and the second enclosure are fastened together to form a closed space inside the enclosure to house the individual battery cells; here, "closed" refers to covering or shutting down, and can be sealed or unsealed; the first enclosure may be a top cover or a bottom plate. As an example, the enclosure may include a top cover, a frame, and a bottom plate. The top cover and the bottom plate are respectively connected to the frame to form a closed space inside the enclosure to house the individual battery cells.

[0071] In the embodiments of this application, the battery cell may include a secondary battery, a primary battery, etc. A secondary battery refers to a battery cell that can be recharged after discharge to activate the active materials and continue to be used. The battery cell may be a lithium-ion battery, a lithium metal battery, a sodium metal battery, a lithium-sulfur battery, a sodium lithium-ion battery, a nickel-metal hydride battery, a nickel-cadmium battery, a lead-acid battery, a sodium-ion battery, or a magnesium-ion battery, etc., and the embodiments of this application are not limited in this regard. The battery cell may be cylindrical, flat, cuboid, or other shapes, etc., and the embodiments of this application are not limited in this regard either. Battery cells are generally divided into three types according to the packaging method: cylindrical battery cells, square battery cells, and pouch battery cells, and the embodiments of this application are not limited in this regard either.

[0072] For example, a battery cell typically includes a housing, a base plate, an electrode assembly, and an electrolyte. The housing houses the electrode assembly and the electrolyte, and has at least one positive electrode post and at least one negative electrode post. The base plate is placed inside the housing and is located at one end of the electrode assembly to support it. The electrode assembly includes one or more electrode components, which are formed by stacking or winding a positive electrode sheet, a negative electrode sheet, and a separator.

[0073] The positive electrode generally includes a positive current collector and a positive active material layer. The positive active material layer is directly or indirectly coated on the positive current collector. The positive current collector without the positive active material layer protrudes from the positive current collector with the positive active material layer. The positive current collector without the positive active material layer serves as a positive electrode tab. Multiple positive electrode tabs are stacked together and form an electrical connection with the positive electrode post. For example, the multiple stacked positive electrode tabs can be directly welded to the positive electrode post to form an electrical connection; or, the electrode assembly can also include a positive electrode adapter piece. The multiple stacked positive electrode tabs are welded to one end of the positive electrode adapter piece, and the other end of the positive electrode adapter piece is welded to the positive electrode post, so that the positive electrode tabs and the positive electrode post form an electrical connection.

[0074] The negative electrode generally includes a negative current collector and a negative active material layer. The negative active material layer is directly or indirectly coated on the negative current collector. The negative current collector without the negative active material layer protrudes from the negative current collector with the negative active material layer. The negative current collector without the negative active material layer serves as a negative electrode tab. Multiple negative electrode tabs are stacked together and form an electrical connection with the negative electrode post. For example, the stacked negative electrode tabs can be directly welded to the negative electrode post to form an electrical connection; alternatively, the electrode assembly may also include a negative electrode adapter piece. The stacked negative electrode tabs are welded to one end of the negative electrode adapter piece, and the other end of the negative electrode adapter piece is welded to the negative electrode post, so that the negative electrode tabs and the negative electrode post form an electrical connection. The material of the separator is not limited; for example, it can be polypropylene or polyethylene.

[0075] The pressure relief valve on the battery cell mentioned in this application is used to release gas inside the battery cell when the internal pressure is too high (e.g., due to overcharging), thereby reducing the internal pressure and preventing the battery cell from exploding due to excessively rapid pressurization. For example, the pressure relief valve can be an explosion-proof valve, an explosion-proof disc, etc.

[0076] With current social development and technological advancements, battery cells are widely used as power sources for portable electronic products such as mobile communications devices, laptops, and digital cameras, as well as energy storage systems for electric vehicles. The lifespan of battery cells is a key concern. As battery cells are used for extended periods, the electrolyte is continuously consumed. To ensure the charge-discharge cycle efficiency of the battery cell, electrolyte is added inside the cell's casing. Under the influence of gravity, some electrolyte adheres to the electrode assembly, while the remaining electrolyte remains at the bottom of the casing.

[0077] In some technologies, both the electrode assembly and the base plate are located inside the housing, with the base plate positioned between the electrode assembly and the bottom of the housing. When the base plate needs to be raised or thickened, the electrolyte on the side of the base plate away from the electrode assembly is not easily transferred to the electrode assembly, making it difficult for the electrode assembly to be fully wetted. This reduces the cycle performance of the electrode assembly and affects the lifespan of the battery cells.

[0078] Based on the above considerations, in order to make fuller use of the electrolyte remaining on the side of the bottom plate away from the electrode assembly, this application proposes a battery cell. The battery cell includes: a housing, an electrode assembly, a pressure relief valve, and a bottom plate. The housing has a receiving cavity and includes a mounting wall that helps define the receiving cavity. The electrode assembly is disposed in the receiving cavity, the pressure relief valve is disposed in the mounting wall, and the bottom plate is disposed in the receiving cavity and located between the electrode assembly and the mounting wall. The bottom plate includes a plate body and at least one protrusion. The protrusion protrudes from the surface of the plate body facing the mounting wall and is offset from the pressure relief valve, so that the bottom plate defines a channel penetrating through both ends of the length of the bottom plate. The channel communicates with the pressure relief valve. A plurality of first capillary pores that allow electrolyte penetration are formed on the bottom plate. The first capillary pores penetrate the plate body and the protrusion along the thickness direction of the plate body.

[0079] In the above technical solution, the first capillary pore penetrates the plate body and the protrusion along the thickness direction of the plate body. The bottom support plate is located between the electrode assembly and the mounting wall. The electrolyte remaining on the side of the bottom support plate facing the mounting wall can easily pass through multiple capillary pores and be transported to the electrode assembly under the action of capillary action. This allows the electrolyte remaining on the side of the bottom support plate facing the mounting wall to be fully utilized, and the electrode assembly can be fully wetted by the electrolyte, which is conducive to improving the cycle performance of the battery cell. The protrusion is protruding from the surface of the plate body facing the mounting wall, so that the bottom support plate defines a channel penetrating both ends of the length of the bottom support plate. When the battery cell experiences thermal runaway, it is convenient to provide venting space for the pressure relief valve, which is beneficial to improving the reliability of the battery cell.

[0080] This application provides an embodiment of an electrical device using the disclosed power supply. The power supply includes the aforementioned battery cell, battery device, energy storage device, or energy storage system. The battery cell or battery device serves as the power source. The power supply can be, but is not limited to, mobile phones, tablets, laptops, electric toys, power tools, electric vehicles, electric cars, ships, spacecraft, etc. Electric toys can include stationary or mobile electric toys, such as game consoles, electric car toys, electric ship toys, and electric airplane toys. Spacecraft can include airplanes, rockets, space shuttles, and spacecraft. Power tools include metal cutting power tools, grinding power tools, assembly power tools, and railway power tools, such as electric drills, electric grinders, electric wrenches, electric screwdrivers, electric hammers, impact drills, concrete vibrators, and electric planers, etc.

[0081] For ease of explanation, the following embodiments use a vehicle as an example to describe in detail the structure of the electrical device 4, battery device 3, and battery cell 2 of this application.

[0082] Please refer to Figure 1 , Figure 1 The electrical device 4 provided in some embodiments of this application is a structural schematic diagram of a vehicle. The vehicle can be a gasoline-powered vehicle, a natural gas-powered vehicle, or a new energy vehicle. New energy vehicles can be pure electric vehicles, hybrid electric vehicles, or range-extended electric vehicles, etc. The vehicle is equipped with a battery device 3, which can be located at the bottom, front, or rear of the vehicle. The battery device 3 can be used to power the vehicle; for example, the battery device 3 can serve as the vehicle's operating power source. The vehicle may also include a controller 60 and a motor 62. The controller 60 is used to control the battery device 3 to supply power to the motor 62, for example, to meet the power needs of the vehicle during starting, navigation, and driving. In some embodiments of this application, the battery device 3 can not only serve as the vehicle's operating power source but also as the vehicle's driving power source, replacing or partially replacing gasoline or natural gas to provide driving power for the vehicle.

[0083] Please refer to Figure 2 The figure shows an exploded view of the structure of a battery cell 2 used in a battery device 3 according to some embodiments of this application. The battery device 3 includes a housing 70 and a plurality of battery cells 2, with the battery cells 2 housed within the housing 70. The housing 70 provides assembly space for the battery cells 2, and can adopt various structures. In some embodiments, the housing 70 may include a first housing 72 and a second housing 74, which cover each other, and together define a cavity for accommodating the battery cells 2. The second housing 74 may be a hollow structure open at one end, and the first housing 72 may be a plate-like structure, with the first housing 72 covering the open side of the second housing 74 so that the first housing 72 and the second housing 74 together define the cavity; alternatively, the first housing 72 and the second housing 74 may both be hollow structures open on one side (e.g., Figure 2 As shown), the open side of the first housing 72 fits onto the open side of the second housing 74. Of course, the housing 70 formed by the first housing 72 and the second housing 74 can be of various shapes, such as a cylinder or a cuboid.

[0084] In the battery device 3, multiple battery cells 2 can be connected in series, parallel, or in a mixed configuration. A mixed configuration means that multiple battery cells 2 are connected in both series and parallel configurations. Multiple battery cells 2 can be directly connected in series, parallel, or in a mixed configuration, and then the entire assembly of the multiple battery cells 2 is housed within the housing 70. Alternatively, the battery device 3 can also consist of multiple battery cells 2 first connected in series, parallel, or in a mixed configuration to form battery modules, and then these battery modules are connected in series, parallel, or in a mixed configuration to form a whole, which is then housed within the housing 70. The battery device 3 may also include other structures; for example, the battery device 3 may also include a busbar for realizing the electrical connection between the multiple battery cells 2.

[0085] Please refer to Figures 3-12 In the embodiments of this application, the battery cell 2 includes a housing 80, an electrode assembly 52, a pressure relief valve 90, and a base plate 1.

[0086] The housing 80 has a receiving cavity 82. The housing 80 includes a mounting wall 84 that defines the receiving cavity 82. The electrode assembly 52 is disposed in the receiving cavity 82. The pressure relief valve 90 is disposed in the mounting wall 84. The bottom support plate 1 is also disposed in the receiving cavity 82, and the bottom support plate 1 is located between the electrode assembly 52 and the mounting wall 84. A portion of the bottom support plate 1 is disposed opposite to the pressure relief valve 90. The bottom support plate 1 includes a plate body portion 10 and at least one protrusion 20. The protrusion 20 protrudes from the surface of the plate body portion 10 facing the mounting wall 84, and the protrusion 20 is offset from the pressure relief valve 90 so that the bottom support plate 1 defines a channel 26 that extends through both ends of the length of the bottom support plate 1. The channel 26 communicates with the pressure relief valve 90.

[0087] As can be seen, the protrusion 20 and the pressure relief valve 90 are offset on the plane where the plate portion 10 is located, so that the orthographic projection of the protrusion 20 and the orthographic projection of the pressure relief valve 90 do not overlap on the plane where the plate portion 10 is located; in other words, a part of the plate portion 10 and the pressure relief valve 90 are offset along the thickness direction of the plate portion 10 (e.g., ...). Figure 6 In the direction of CC', the plate portion 10 is opposite to the pressure relief valve 90, and the portion of the plate portion 10 opposite to the pressure relief valve 90 does not have a protrusion 20, so that the channel 26 communicates with the pressure relief valve 90. The sum of the areas occupied by the protrusions 20 is less than the surface area of ​​the thickness side of the plate portion 10. The surface of the plate portion 10 facing the mounting wall 84 can help define the wall surface of the channel 26, and the outer peripheral wall of the protrusion 20 can also help define the wall surface of the channel 26. The channel 26 can penetrate the base plate 1 in the length direction (e.g., in the direction of CC'). Figure 4 One end of the channel 26 in the AA' direction forms a first connection port, and the channel 26 can penetrate the other end of the bottom support plate 1 in the length direction to form a second connection port. When the battery cell 2 experiences thermal runaway, the emissions generated inside the battery cell 2 can flow through the first connection port and / or the second connection port to the channel 26, to the side of the plate body 10 facing the mounting wall 84, and flow toward the pressure relief valve 90, which is beneficial to improving the pressure relief smoothness and reliability of the battery cell 2. Obviously, the presence of the protrusion 20 can appropriately increase the distance between the plate body 10 and the mounting wall 84, and appropriately increase the flow area of ​​the channel 26, which is beneficial to further improve the pressure relief smoothness of the battery cell 2.

[0088] The protrusion 20 is located on the side of the plate 10 away from the electrode assembly 52. ​​The empty space formed by the protrusion 20 and the mounting wall 84 facilitates the increase of the electrolyte storage capacity inside the housing 80. The pressure relief valve 90 is located on the mounting wall 84 and on the side of the bottom plate 1 away from the electrode assembly 52. ​​The empty space formed by the protrusion 20 and the mounting wall 84 provides more space for the installation of the pressure relief valve 90, making the installation of the pressure relief valve 90 more convenient. At the same time, due to the existence of the empty space, the pressure relief valve 90 is not directly subjected to pressure, reducing the possibility of deformation and damage to the pressure relief valve 90, and improving the reliability of the pressure relief valve 90.

[0089] Furthermore, the base plate 1 has multiple first capillary pores 30 formed on it, allowing electrolyte to penetrate. These first capillary pores 30 penetrate the plate body 10 and the protrusion 20 along the thickness direction of the plate body 10. It can be understood that the base plate 1 is inside the housing 80 of the battery cell 2, and the base plate 1 supports the electrode assembly 52, thus separating the electrode assembly 52 from the housing 80. This reduces the possibility of interference between the electrode assembly 52 and the housing 80, especially reducing the probability of interference between the corners of the electrode assembly 52 and the corners of the housing 80, thereby facilitating the use and transportation of the battery cell 2.

[0090] As can be seen, the base plate 1 includes a plate body 10 and at least one protrusion 20. A first capillary pore 30 is formed on the base plate 1, and the first capillary pore 30 penetrates the plate body 10 and the protrusion 20 along the thickness direction of the plate body 10. Thus, the first capillary pore 30 can connect both sides of the maximum thickness of the base plate 1 and is not easily affected by the protrusion 20. In other words, if the first capillary pore 30 only penetrates the plate body 10, due to the presence of the protrusion 20, the first capillary pore 30 may have a certain gap with the small amount of electrolyte located on the side of the plate body 10 facing the mounting wall 84, making it difficult for the first capillary pore 30 to transmit electrolyte through capillary action. Therefore, the first capillary pore 30 penetrates the area where the plate body portion 10 and the protrusion portion 20 coexist, facilitating better contact with the electrolyte. Even if the amount of electrolyte remaining on the side of the bottom plate 1 facing the mounting wall 841 is small, the electrolyte can still pass through the first capillary pore 30 and, under the action of capillary action, be smoothly transported from the side of the bottom plate 1 facing the mounting wall 84 to the side of the bottom plate 1 facing away from the mounting wall 84, and then to the electrode assembly 52. ​​This allows for more effective utilization of the electrolyte remaining inside the battery cell 2 housing 80. Here, capillary action refers to the phenomenon where wetting liquid rises in a thin tube and non-wetting liquid falls in a thin tube.

[0091] For example, the mounting wall 84 is the bottom wall of the housing 80. As the battery cell 2 is used for longer periods, the electrolyte is continuously consumed. To ensure the charge-discharge cycle efficiency of the battery cell 2, electrolyte is added into the housing 80 of the battery cell 2. Under the influence of gravity, a portion of the electrolyte is adsorbed onto the electrode assembly 52, while the remaining electrolyte remains at the bottom of the housing 80. The bottom support plate 1 is located between the electrode assembly 52 and the mounting wall 84. The bottom support plate 1 has a first capillary pore 30 that penetrates the plate body portion 10 and the protrusion portion 20. The first capillary pore 30 can contact the electrolyte remaining at the bottom of the housing 80, facilitating the smooth delivery of the electrolyte to the electrode assembly 52 through the first capillary pore 30. This allows the electrolyte remaining at the bottom of the housing 80 to be fully utilized, and the electrode assembly 52 to be fully wetted by the electrolyte, thereby improving the cycle performance of the electrode assembly 52 and extending the service life of the battery cell 2.

[0092] Please refer to Figure 4 , Figure 8 and Figure 11 In some embodiments, there are multiple protrusions 20, and the multiple protrusions 20 are along the length direction and / or width direction of the plate body portion 10 (e.g., Figure 4 The BB' direction) interval setting.

[0093] As can be seen, multiple protrusions 20 are spaced apart along the length and / or width of the plate portion 10. The multiple protrusions 20 are spaced apart in the length and / or width of the plate portion 10, which facilitates increasing the support range of the protrusions 20, making the electrode assembly 52 placed on the base plate 1 more stable, which is beneficial to the use and transportation of the battery cell 2. The above-mentioned arrangement of the multiple protrusions 20 makes it easy for the formed channel 26 to pass through both ends of the length of the base plate 1.

[0094] Please refer to Figure 4 In some embodiments, the protrusion 20 extends in a long strip shape along the length or width direction of the plate portion 10.

[0095] As can be seen, the protrusion 20 extends into a long strip shape along the length or width direction of the plate body 10, so that the protrusion 20 occupies a larger area on the plate body 10, which makes it easier to increase the support area of ​​the protrusion 20, making the electrode assembly 52 placed on the base plate 1 more stable, which is beneficial to the use and transportation of the battery cell 2. At the same time, it is beneficial to increase the contact area between the protrusion 20 and the electrolyte, so as to increase the arrangement area of ​​the first capillary pore 30, which is beneficial to improve the utilization rate of the electrolyte. Moreover, the long strip-shaped protrusion 20 has a relatively simple structure, which is convenient for the processing of the base plate 1.

[0096] Please refer to Figures 3-12 In some embodiments, the base plate 1 is configured to satisfy at least one of the following conditions: Condition A1, the base plate 1 is a one-piece molded part, and the base plate 1 is a polypropylene part, a polyethylene part, a polyethylene terephthalate part, or a polyimide part; Condition A2, the thickness t1 of the plate body portion 10 satisfies 0.3mm≤t1≤0.8mm; Condition A3, the pore diameter d of the first capillary pore 30 satisfies 0.01mm≤d≤1mm; Condition A4, the thickness t2 of the protrusion 20 satisfies 0.2mm≤t2≤5mm; Condition A5, the thickness t2 of the protrusion 20 is greater than the thickness t1 of the plate body portion 10.

[0097] As can be seen, in condition A1, the base plate 1 is a one-piece molded part, that is, the protrusion 20 and the plate body 10 are integrally molded. The one-piece molding design makes the connection between the various parts of the base plate 1 more solid, without additional seams or connection points, thereby improving the structural strength and stability of the base plate 1. The base plate 1 is made of polypropylene, polyethylene, polyethylene terephthalate or polyimide. These materials all have good chemical corrosion resistance and can effectively resist the erosion of electrolyte, so that the base plate 1 can maintain structural stability in long-term contact with electrolyte, thereby improving the reliability of the battery cell 2.

[0098] In condition A2, the thickness t1 of the plate portion 10 satisfies 0.3mm≤t1≤0.8mm. When the thickness of the plate portion 10 is too small (e.g., t1<0.3mm), the thinness of the plate portion 10 may reduce the structural strength of the base plate 1, thereby reducing the ability of the base plate 1 to resist external impacts and vibrations, thus increasing the risk of damage to the battery cell 2 during use. When the thickness of the plate portion 10 is too large (e.g., t1>0.8mm), the excessive thickness of the plate portion 10 will increase the overall weight of the base plate 1, thereby increasing the overall weight of the battery cell 2. Moreover, the excessively thick plate portion 10 will occupy more space inside the casing 80 of the battery cell 2, thus affecting the energy density of the battery cell 2. By setting the thickness of the plate portion 10 in the range of 0.3mm to 0.8mm, the plate portion 10 can provide sufficient structural strength to support the electrode assembly 52 while maintaining a relatively light weight. For example, t1 can be 0.3mm, 0.4mm, 0.58mm, 0.7mm, 0.72mm, 0.8mm, etc.

[0099] In condition A3, the pore diameter d of the first capillary pore 30 satisfies 0.01mm ≤ d ≤ 1mm. When the pore diameter of the first capillary pore 30 is too small (e.g., d < 0.01mm), the small pore diameter may affect the smooth penetration process of the electrolyte, resulting in a decrease in the total amount of electrolyte transferred through the first capillary pore 30. Consequently, the improvement in the cycle performance of the electrode assembly 52 is limited. Furthermore, the small pore diameter makes the base plate 1 more difficult to process, which is not conducive to manufacturing. When the pore diameter of the first capillary pore 30 is too large (e.g., d > 1mm), Excessively large pore size may weaken the overall structural strength of the base plate 1, making it more susceptible to external stress and increasing the risk of damage to the electrode assembly 52. ​​By setting the pore size d of the first capillary pore 30 within the range of 0.01 mm to 1 mm, an appropriate pore size allows the electrolyte to penetrate into the electrode assembly 52 at an appropriate rate and quantity without significantly weakening the overall structural strength of the base plate 1, thus maintaining the stability and durability of the base plate 1. Furthermore, an appropriate pore size makes the manufacturing of the base plate 1 more convenient. For example, d can be 0.01 mm, 0.12 mm, 0.25 mm, 0.38 mm, 0.45 mm, 0.6 mm, 0.66 mm, 0.72 mm, 0.83 mm, 0.86 mm, 0.92 mm, or 1 mm.

[0100] In condition A4, the thickness t2 of the protrusion 20 satisfies 0.2mm≤t2≤5mm. When the thickness of the protrusion 20 is too small (e.g., t2<0.2mm), the protrusion 20 will be too thin, which will weaken its structural strength and reduce its ability to withstand pressure and vibration, increasing the risk of damage to the battery cell 2. When the thickness of the protrusion 20 is too large (e.g., t2>5mm), the thickness of the protrusion 20 will increase the weight of the base plate 1, thereby increasing the overall weight of the battery cell 2. Moreover, the excessively thick protrusion 20 will occupy more space inside the housing 80 of the battery cell 2, thus affecting the energy density of the battery cell 2. By setting the thickness of the protrusion 20 in the range of 0.2mm to 5mm, the protrusion 20 can provide sufficient structural strength to support the electrode assembly 52 while maintaining a relatively light weight. For example, t2 can be 0.2mm, 0.4mm, 0.68mm, 1.2mm, 2.6mm, 3.2mm, 3.8mm, 4.2mm, 4.68mm, 4.8mm, 5mm, etc.

[0101] In condition A5, the thickness of the protrusion 20 is greater than the thickness of the plate 10. The thickened design of the protrusion 20 can enhance the resistance of the base plate 1 to external impact. Moreover, the end face of the protrusion 20 away from the plate 10 has a larger gap between the plate 10 and the plate 10 in the thickness direction of the base plate 1. This results in a larger empty space between the plate 10 and the mounting wall 84, providing more space for the storage of electrolyte in the housing 80 and the flow of the channel 26.

[0102] Please refer to Figure 4 and Figure 5 In some embodiments, the base plate 1 satisfies condition A3, 0.1mm≤d≤0.5mm.

[0103] It can be seen that by setting the pore size of the first capillary pore 30 in the range of 0.1 mm to 0.5 mm, the smaller pore size can enhance the capillary effect, making it easier for the electrolyte to be transported to the electrode assembly 52. ​​For example, d can be 0.1 mm, 0.15 mm, 0.23 mm, 0.31 mm, 0.36 mm, 0.42 mm, 0.5 mm, etc.

[0104] Please refer to Figure 4 , Figure 8 and Figure 11 In some embodiments, the size of the protrusion 20 is smaller than the width of the plate portion 10 in the width direction.

[0105] As can be seen, since the size of the protrusion 20 is smaller than the width of the plate portion 10, the protrusion 20 will not completely block the flow of electrolyte in the width direction of the bottom support plate 1. This facilitates the formation of a channel 26 that is completely penetrating in the length direction between the protrusion 20 and the plate portion 10, allowing the electrolyte to flow freely in the length direction of the bottom support plate 1. This makes the electrolyte more evenly distributed in the housing 80, which helps to improve the uniformity of wetting of the electrode assembly 52.

[0106] Please refer to Figure 4 In some embodiments, the plurality of protrusions 20 include a first protrusion 22 and a plurality of second protrusions 23. The plurality of second protrusions 23 are spaced apart along the length direction of the plate portion 10. At least one first protrusion 22 is spaced apart on both sides of the plurality of second protrusions 23 in the width direction of the plate portion 10. The first protrusion 22 extends along the length direction of the plate portion 10, and the length of the first protrusion 22 is greater than or equal to half the length of the plate portion 10.

[0107] As can be seen, the second protrusions 23 are spaced apart along the length of the plate body 10. The multiple second protrusions 23 are spaced apart on both sides of the width of the plate body 10, and at least one first protrusion 22 is provided. Thus, there can be at least two first protrusions 22. The distribution of the multiple protrusions 20 on the plate body 10 is more uniform, which facilitates increasing the support range of the multiple protrusions 20 and making the protrusions 20 have a more stable support effect. Moreover, the wetting effect of the protrusions 20 on the electrode assembly 52 is more balanced through the above-mentioned distribution. The length of the first protrusion 22 is greater than or equal to half the length of the plate body 10, which facilitates increasing the support area of ​​the first protrusion 22 and making the support effect of the protrusion 20 better. Furthermore, the bottom plate 1 can have a larger number of first capillary pores 30, which facilitates improving the wetting effect of the electrolyte on the electrode assembly 52.

[0108] Please refer to Figure 4 In some embodiments, the two outermost protrusions of the plurality of second protrusions 23 extend to be flush with the length end of the plate portion 10, and the two ends of the length of the first protrusion 22 extend to be flush with the corresponding length ends of the plate portion 10.

[0109] As can be seen, one of the second protrusions 23 adjacent to one end of the length of the plate portion 10 extends to be flush with one end of the length of the plate portion 10, and another of the second protrusions 23 adjacent to the other end of the length of the plate portion 10 extends to be flush with the other end of the length of the plate portion 10. The two ends of the length of the first protrusion 22 extend to be flush with the corresponding two ends of the length of the plate portion 10, providing additional support for the edge area of ​​the plate portion 10, which helps to enhance the shear resistance and tear resistance of the edge of the plate portion 10. Moreover, the support area of ​​the first protrusion 22 and the second protrusion 23 is larger, which facilitates the improvement of the support effect of the protrusion 20. At the same time, it is convenient to set more first capillary pores 30 on the bottom plate 1 to enhance the wetting effect of the electrolyte on the electrode assembly 52.

[0110] Please refer to Figure 6 and Figure 7 In some embodiments, the thickness t2 of the protrusion 20 satisfies 0.6mm≤t2≤5mm. When the thickness of the protrusion 20 is too small (e.g., t2<0.6mm), the protrusion 20 is too thin, which will weaken its structural strength and reduce its ability to withstand pressure and vibration, increasing the risk of damage to the battery cell 2. When the thickness of the protrusion 20 is too large (e.g., t2>5mm), the excessive thickness of the protrusion 20 will increase the weight of the base plate 1, thereby increasing the overall weight of the battery cell 2. Moreover, the excessively thick protrusion 20 will occupy more space inside the housing 80 of the battery cell 2, thus affecting the energy density of the battery cell 2. By setting the protrusion 20 in the range of 0.6mm to 5mm, the thickness of the protrusion 20 is matched with the arrangement of the first protrusion 22 and the second protrusion 23. The protrusion 20 can provide sufficient structural strength to support the electrode assembly 52 while maintaining a light weight. For example, t2 can be 0.6mm, 0.8mm, 1.02mm, 1.2mm, 2.6mm, 3.2mm, 3.8mm, 4.2mm, 4.68mm, 4.8mm, 5mm, etc.

[0111] Please refer to Figure 6 and Figure 7 In some embodiments, 1mm ≤ t2 ≤ 3mm. By limiting the thickness of the protrusion 20 to the range of 1mm to 3mm, it is easier to adapt to the bottom support plate 1 configuration where "multiple second protrusions 23 can be located between two first protrusions 22, or a first protrusion 22 is located on one side of multiple second protrusions 23". This allows for a better match between the thickness of the protrusion 20 and the plate body 10, resulting in good support for the protrusion 20 and facilitating the manufacturing of the bottom support plate 1. For example, t2 can be 1mm, 1.2mm, 1.45mm, 1.63mm, 1.82mm, 2.12mm, 2.34mm, 2.58mm, 2.85mm, 3mm, etc.

[0112] Please refer to Figure 8 In some embodiments, a plurality of protrusions 20 spaced apart along the length of the plate portion 10 are configured as protrusion groups 25. There are multiple protrusion groups 25, and the multiple protrusion groups 25 are spaced apart along the width of the plate portion 10. The protrusions 20 of two adjacent protrusion groups 25 are arranged facing each other along the width of the plate portion 10.

[0113] As can be seen, multiple protrusions 20 spaced apart along the length of the plate portion 10 form a protrusion group 25. The protrusions 20 of the multiple protrusion groups 25 are arranged facing each other along the width of the plate portion 10, which makes the support range of the multiple protrusions 20 larger and the distribution of the multiple protrusions 20 on the bottom support plate 1 more uniform, making the support effect provided by the protrusions 20 more stable, and the structure is relatively simple and easy to process and manufacture.

[0114] Please refer to Figure 10 In some embodiments, the thickness t2 of the protrusion 20 satisfies 0.2mm≤t2≤3mm. When the thickness of the protrusion 20 is too small (e.g., t2<0.2mm), the protrusion 20 is too thin, which will weaken its structural strength and reduce its ability to withstand pressure and vibration, increasing the risk of damage to the battery cell 2. When the thickness of the protrusion 20 is too large (e.g., t2>3mm), the excessive thickness of the protrusion 20 will increase the weight of the base plate 1, thereby increasing the overall weight of the battery cell 2. Moreover, the excessively thick protrusion 20 will occupy more space inside the housing 80 of the battery cell 2, thus affecting the energy density of the battery cell 2. By setting the protrusion 20 in the range of 0.2mm to 3mm, the thickness of the protrusion 20 is matched with the arrangement of multiple protrusion groups 25. The protrusion 20 can provide sufficient structural strength to support the electrode assembly 52 while maintaining a light weight. For example, t2 can be 0.2mm, 0.4mm, 0.68mm, 0.72mm, 0.8mm, 1.2mm, 2.3mm, 2.5mm, 2.82mm, 3mm, etc.

[0115] Please refer to Figure 10 In some embodiments, 1mm ≤ t2 ≤ 2mm. By limiting the thickness of the protrusion 20 to the range of 1mm to 2mm, it is easier to adapt to the bottom support plate 1 where "the protrusions 20 of multiple sets of protrusion groups 25 are arranged facing each other along the width direction of the plate body 10". This allows for a better match between the thickness of the protrusion 20 and the plate body 10, resulting in good support for the protrusion 20 and facilitating the manufacturing of the bottom support plate 1. For example, t2 can be 1mm, 1.2mm, 1.32mm, 1.43mm, 1.5mm, 1.64mm, 1.67mm, 1.75mm, 1.83mm, 2mm, etc.

[0116] Please refer to Figure 11In some embodiments, the pressure relief valve 90 is located at the middle of the mounting wall 84 in the length direction, so the pressure relief valve 90 can be opposite to the center position of the plate portion 10 in the length direction. The channel 26 includes a first channel segment 260 and a second channel segment 262 that are connected along the length direction of the plate portion 10. The flow area of ​​at least a portion of at least one of the first channel segment 260 and the second channel segment 262 decreases along the length direction of the plate portion 10 towards the center position of the plate portion 10 in the length direction. The width of at least a portion of at least one of the first channel segment 260 and the second channel segment 262 in the width direction of the plate portion 10 decreases along the length direction of the plate portion 10 towards the center position of the plate portion 10 in the length direction. It can be understood that the length direction of the mounting wall 84 is the length direction of the plate portion 10 and the length direction of the base plate 1.

[0117] As can be seen, the plate portion 10 and the protrusion 20 define a channel 26 that extends through both ends of the length of the base plate 1. At least a portion of the flow area of ​​at least one of the first channel segment 260 and the second channel segment 262 decreases along the length direction of the plate portion 10 towards the center position in the length direction. This defines at least a portion of the width of at least one of the protrusions 20 in the first channel segment 260 and the second channel segment 262 that increases towards the center position in the length direction. This results in a larger contact area of ​​the protrusion 20 at the center position of the plate portion 10, which facilitates increasing the structural strength of the base plate 1 at the center position and improving the support effect of the base plate 1. Furthermore, the electrolyte can be more evenly distributed within the channel 26 formed by the plate portion 10 and the protrusion 20, which facilitates improving the wetting effect of the electrolyte on the electrode assembly 52. ​​At the same time, due to the above-mentioned arrangement of the flow area of ​​the channel 26, the emissions emitted when the battery cell 2 runs out of control can flow through the above-mentioned at least portion of the channel 26 more quickly, so as to use vortices to increase the flow rate toward the pressure relief valve 90, thereby improving the pressure relief rate of the battery cell 2.

[0118] Please refer to Figure 11 In some embodiments, the plurality of protrusions 20 include a third protrusion 27 and a fourth protrusion 28 spaced apart along the width direction of the plate portion 10, and a channel 26 is formed between the third protrusion 27 and the fourth protrusion 28. At least one of the third protrusion 27 and the fourth protrusion 28 protrudes towards the center of one side surface of the other.

[0119] As can be seen, at least one of the third protrusion 27 and the fourth protrusion 28 protrudes from the center of one side surface toward the other, so the third protrusion 27 and / or the fourth protrusion 28 form an arch-like structure, which facilitates increasing the structural strength and contact area of ​​the base plate 1 at the center position, so that the base plate 1 can more effectively disperse stress when subjected to external force, thereby giving the base plate 1 a more stable support effect. At the same time, it is convenient to realize that at least part of the flow area of ​​the channel 26 decreases toward the center position of the plate 10 in the length direction.

[0120] Please refer to Figure 11 In some embodiments, the plurality of protrusions 20 include a third protrusion 27, a fourth protrusion 28 and a plurality of fifth protrusions 29 spaced apart along the width direction. The plurality of fifth protrusions 29 are spaced apart along the length direction and are located between the third protrusion 27 and the fourth protrusion 28. The outermost two of the fifth protrusions 29 extend to be flush with the plate body portion 10 at the length end, so that the electrolyte is more evenly distributed on the base plate 1 and the support range of the plurality of protrusions 20 is larger, which facilitates increasing the support effect of the base plate 1.

[0121] Taking two fifth protrusions 29 as an example, the two fifth protrusions 29 are respectively provided at both ends of the length of the plate body 10. The length of each fifth protrusion 29 is less than 1 / 4 of the length of the plate body 10. One fifth protrusion 29 is provided corresponding to the first channel segment 260, and the other fifth protrusion 29 is provided corresponding to the second channel segment 262. The flow area of ​​the portion of the first channel segment 260 located between the one fifth protrusion 29 and the other fifth protrusion 29 decreases towards the center position of the plate body 10 in the length direction. The flow area of ​​the portion of the second channel segment 262 located between the other fifth protrusion 29 and the one fifth protrusion 29 decreases towards the center position of the plate body 10 in the length direction.

[0122] Please refer to Figure 4 , Figure 8 and Figure 11 In some embodiments, a plurality of spaced positioning holes 40 are formed on the base plate 1. The positioning holes 40 correspond to the protrusions 20, or the positioning holes 40 and the protrusions 20 are avoided. The opening area of ​​the positioning holes 40 is larger than the opening area of ​​the first capillary pores 30.

[0123] As can be seen, multiple spaced positioning holes 40 are formed on the base plate 1, which enables the base plate 1 to be accurately positioned when it is installed with the housing 80 of the battery cell 2, helping to reduce installation errors and facilitating the positioning and installation of the base plate 1. The positioning holes 40 correspond to the protrusions 20, that is, the positioning holes 40 are formed on the protrusions 20, which helps to reduce the amount of material used in manufacturing the base plate 1 and also makes it easier to increase the mating length of the positioning holes 40, making the base plate 1 more stable during use. Alternatively, the positioning holes 40 and the protrusions 20 are set to avoid each other, which makes it less likely to form a weak area on the protrusions 20 and improves the support effect of the protrusions 20. The opening area of ​​the positioning holes 40 is larger than the opening area of ​​the first capillary pores 30, that is, the diameter of the positioning holes 40 is larger than the diameter of the first capillary pores 30, which makes it easier for workers to distinguish between the positioning holes 40 and the first capillary pores 30, and facilitates the installation of the base plate 1.

[0124] Please refer to Figure 4 , Figure 8 and Figure 11 In some embodiments, the positioning hole 40 is located at the center of the base plate 1 in its width direction, and all the protrusions 20 are about the center line of the base plate 1 (e.g., Figure 4 The L1 in the middle is symmetrically arranged, and the center line extends along the length direction of the plate body 10.

[0125] As can be seen, the positioning hole 40 is located in the middle of the width direction of the base plate 1, providing a clear reference point for positioning the base plate 1 during installation, which facilitates the installation of the base plate 1. Moreover, the setting of the positioning hole 40 makes the base plate 1 more evenly distributed when under force, which helps to reduce stress concentration caused by uneven force. All the protrusions 20 are symmetrically arranged about the center line of the base plate 1, which makes the base plate 1 more balanced when under force and the stress distribution on the base plate 1 more even, which helps to improve the support stability of the multiple protrusions 20. In addition, the first capillary pore 30 penetrates the protrusion 20, which makes the distribution of the first capillary pore 30 more even, which helps to provide a more uniform wetting effect for the electrode assembly 52, and helps to improve the cycle performance of the battery cell 2.

[0126] Please refer to Figure 13 and Figure 14 In some embodiments, the battery cell 2 further includes an insulating film 54 disposed in the receiving cavity 82 and covering the electrode assembly 52. ​​The insulating film 54 is connected to the base plate 1, and a second capillary pore 540 is formed on the portion of the insulating film 54 disposed between the electrode assembly 52 and the base plate 1, which allows the electrolyte to permeate.

[0127] As can be seen, since the insulating film 54 covers the electrode assembly 52 and is connected to the base plate 1, the insulating film 54 can effectively isolate the electrical contact between the electrode assembly 52 and the housing 80, thereby reducing the possibility of the housing 80 being charged. The insulating film 54 has a second capillary pore 540 for electrolyte penetration. Through the cooperation of the first capillary pore 30 and the second capillary pore 540, the electrolyte can be better transported to the electrode assembly 52, which facilitates the improvement of the cycle performance of the battery cell 2.

[0128] It is understood that in the embodiments of this application, the second capillary pore 540 and the first capillary pore 30 can be opposite to each other or staggered, neither of which will affect the penetration of the electrolyte into the electrode assembly 52 under capillary action.

[0129] Secondly, embodiments of this application provide a battery device 3, including a plurality of battery cells 2 according to the second aspect.

[0130] In the above technical solution, the battery device 3 includes multiple battery cells 2, and the battery cells 2 have good stability and cycle performance. This facilitates improvements in the stability and lifespan of the battery device 3.

[0131] Thirdly, embodiments of this application provide an electrical device 4, including a battery device 3, which is used to provide electrical energy.

[0132] In the above technical solution, the electrical device 4 includes a battery device 3, which provides electrical energy. The battery device 3 has good stability and service life. Therefore, the battery device 3 provides electrical energy more stably, which helps to improve the stability of the electrical device 4 during operation.

[0133] It should be noted that, unless otherwise specified, the embodiments and features described in this application can be combined with each other.

[0134] The above are merely preferred embodiments of this application and are not intended to limit this application. Various modifications and variations can be made to this application by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this application should be included within the protection scope of this application.

Claims

1. A battery cell, characterized by, include: A housing having a receiving cavity, the housing including a mounting wall that helps define the receiving cavity; An electrode assembly disposed in the receiving cavity; A pressure relief valve, wherein the pressure relief valve is disposed on the mounting wall; A base plate is disposed in the receiving cavity and located between the electrode assembly and the mounting wall. The base plate includes a plate body and at least one protrusion. The protrusion protrudes from the side surface of the plate body facing the mounting wall and is offset from the pressure relief valve, so that the base plate defines a channel penetrating both ends of the length of the base plate. The channel communicates with the pressure relief valve. A plurality of first capillary pores capable of allowing electrolyte permeation are formed on the base plate. The first capillary pores penetrate the plate body and the protrusion along the thickness direction of the plate body.

2. The battery cell of claim 1, wherein, The protrusions are multiple, and the multiple protrusions are spaced apart along the length direction and / or width direction of the plate body.

3. The battery cell of claim 1, wherein, The protrusion extends into a long strip along the length or width of the plate.

4. The battery cell of claim 1, wherein, The base plate is configured to satisfy at least one of the following conditions: Condition A1: The base plate is a one-piece molded part, and is made of polypropylene, polyethylene, polyethylene terephthalate or polyimide. Condition A2: The thickness t1 of the plate body satisfies 0.3mm ≤ t1 ≤ 0.8mm; Condition A3: The pore diameter d of the first capillary pore satisfies 0.01mm≤d≤1mm; Condition A4: The thickness t2 of the protrusion satisfies 0.2mm≤t2≤5mm; Condition A5: The thickness of the protrusion is greater than the thickness of the plate body.

5. The battery cell of claim 4, wherein, The base plate satisfies condition A3, 0.1mm≤d≤0.5mm.

6. The battery cell of claim 1, wherein, In the width direction of the plate body portion, the size of the protrusion is smaller than the width of the plate body portion.

7. The battery cell of claim 6, wherein, The plurality of protrusions include a first protrusion and a plurality of second protrusions. The plurality of second protrusions are spaced apart along the length direction of the plate portion. At least one first protrusion is spaced apart on each side of the plurality of second protrusions in the width direction of the plate portion. The first protrusions extend along the length direction of the plate portion, and the length of the first protrusions is greater than or equal to half the length of the plate portion.

8. The battery cell of claim 7, wherein, The two outermost protrusions of the plurality of second protrusions extend to be flush with the length end of the plate portion, and the two ends of the length of the first protrusion extend to be flush with the corresponding length ends of the plate portion.

9. The battery cell of claim 7, wherein, The thickness t2 of the protrusion satisfies 0.6mm≤t2≤5mm.

10. The battery cell of claim 9, wherein, 1mm≤t2≤3mm.

11. The battery cell of claim 6, wherein, Multiple protrusions spaced apart along the length of the plate portion form a protrusion group. The protrusion group consists of multiple groups and is spaced apart along the width of the plate portion. The protrusions of two adjacent groups of protrusions face each other along the width of the plate portion.

12. The battery cell of claim 11, wherein, The thickness t2 of the protrusion satisfies 0.2mm≤t2≤3mm.

13. The battery cell of claim 12, wherein, 1mm≤t2≤2mm.

14. The battery cell of claim 6, wherein, The pressure relief valve is arranged at a middle portion of the mounting wall in a length direction, the passage includes a first passage segment and a second passage segment which are arranged in communication in a length direction of the plate body portion, and a flow area of at least a portion of at least one of the first passage segment and the second passage segment decreases toward a center position of the plate body portion in the length direction.

15. The battery cell of claim 14, wherein, The plurality of protruding portions includes a third protruding portion and a fourth protruding portion which are arranged in spaced apart relation in a width direction of the plate body portion, the passage is formed between the third protruding portion and the fourth protruding portion, and at least one of the third protruding portion and the fourth protruding portion protrudes toward a middle portion of a side surface of the other.

16. The battery cell of claim 1, wherein, The bottom support plate has a plurality of positioning holes formed therein in spaced apart relation, the positioning holes correspond to the protruding portions, or the positioning holes are arranged away from the protruding portions, and an opening area of the positioning holes is greater than an opening area of the first capillary holes.

17. The battery cell of claim 16, wherein, The positioning holes are arranged at a middle portion of the bottom support plate in a width direction thereof, and all of the protruding portions are arranged in symmetrical relation about a center line of the bottom support plate which extends in a length direction of the plate body portion.

18. The battery cell of any one of claims 1-17, wherein, Further comprising: An insulating film is arranged in the accommodation cavity and covers the electrode assembly, the insulating film is connected to the bottom support plate, and a portion of the insulating film which is arranged between the electrode assembly and the bottom support plate has second capillary holes formed therein which allow electrolyte to permeate.

19. A battery device characterized by comprising: A plurality of battery cells according to any one of claims 1-18 are included.

20. An electrical device, comprising: A battery device according to claim 19 is included for providing electrical energy.

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