Battery monomer, battery and electric equipment

Abstract

The invention discloses a single battery, a battery and electric equipment, the single battery comprises a shell, the shell defines a containing cavity, and the bottom of the shell is provided with an anti-explosion valve; the bottom support is arranged on the bottom wall of the containing cavity, the bottom support comprises a supporting plate, and the surface of the side, facing the bottom wall of the containing cavity, of the supporting plate is a first surface; the supporting frame comprises at least one first supporting rib, the first supporting rib is arranged on the first surface and extends in the length direction of the supporting plate, and the at least one first supporting rib is arranged on the first surface and is arranged on at least one side edge of the supporting plate in the width direction; an airflow channel communicated with the anti-explosion valve is defined among the first supporting rib, the first surface and the bottom wall of the containing cavity. According to the battery monomer disclosed by the invention, a relatively large discharge space can be formed in the battery monomer, so that the exhaust effect can be improved, and the probability of thermal runaway of the battery monomer and the risk of shell welding seam cracking caused by excessive pressure are effectively reduced.

Description

Technical Field

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

[0002] Relevant technologies point out that ultra-thin diaphragms are currently used in the production of battery cells. The use of ultra-thin diaphragms reduces the volume of electrode assemblies, reduces group margin, and increases energy density, thereby creating space for increasing the capacity of electrode assemblies. As the capacity of electrode assemblies increases, the gas production of battery cells also increases, and the probability of thermal runaway of battery cells and the risk of shell weld cracking due to excessive pressure also increase.

[0003] In order to prevent the released gas and particulate matter from entering the passenger compartment, an explosion-proof valve is currently installed at the bottom of the battery cell. However, this solution is prone to poor exhaust, which makes it difficult for the gas to flow to the explosion-proof valve for timely discharge, further increasing the probability of thermal runaway of the battery cell. Summary of the invention

[0004] The present invention aims to solve at least one of the technical problems existing in the prior art. To this end, the present invention proposes a battery cell, which can form a large discharge space inside the battery cell, so that a large amount of gas generated by the battery cell during the cycle can be guided to the explosion-proof valve through the air flow channel and discharged through the explosion-proof valve, thereby improving the exhaust effect, effectively reducing the internal pressure of the battery cell, and reducing the probability of thermal runaway of the battery cell and the risk of shell weld cracking caused by excessive pressure.

[0005] The present invention also provides a battery having the battery cell.

[0006] The present invention also provides an electrical device having the battery.

[0007] According to the first aspect of the present invention, the battery cell comprises: a shell, the shell defines a accommodating cavity, and an explosion-proof valve is provided at the bottom of the shell; a bottom bracket, the bottom bracket is arranged on the bottom wall of the accommodating cavity, and the bottom bracket comprises: a support plate, and the side surface of the support plate facing the bottom wall of the accommodating cavity is a first surface; a support frame, the support frame comprises at least one first support rib, the first support rib is arranged on the first surface and extends along the length direction of the support plate, at least one first support rib is arranged on the first surface and is respectively arranged on at least one side edge of the support plate in the width direction, and an air flow channel connected to the explosion-proof valve is defined between the first support rib, the first surface and the bottom wall of the accommodating cavity; an electrode assembly, the electrode assembly is arranged in the accommodating cavity and supported by the second surface of the support plate, and the first surface and the second surface are arranged opposite to each other in the thickness direction of the support plate.

[0008] According to the battery cell of the present invention, by providing an air flow channel jointly defined by a bottom bracket and the bottom wall of the accommodating cavity, a larger discharge space can be formed inside the battery cell, so that a large amount of gas generated by the battery cell during the cycle process can be guided to the explosion-proof valve through the air flow channel and discharged through the explosion-proof valve, thereby improving the exhaust effect of the battery cell, effectively reducing the internal pressure of the battery cell, and reducing the probability of thermal runaway of the battery cell and the risk of shell weld cracking due to excessive pressure.

[0009] In some embodiments, the number of the first support ribs is two, and the two first support ribs are respectively arranged on both side edges of the support plate in the width direction, and at least parts of the two first support ribs are respectively flush with the both side edges of the support plate in the width direction.

[0010] In this embodiment, by providing two first support ribs, and at least parts of the two first support ribs are flush with the two side edges of the support plate in the width direction, the probability of forming a flow stagnation zone at the first support rib and the edge of the support plate can be effectively reduced, and the bulging phenomenon caused by the gathering of airflow at the connection between the first support rib and the support plate can be effectively reduced, so that a large amount of gas can enter the airflow channel from both ends of the airflow channel, thereby improving the exhaust effect; at the same time, the cross-sectional area of ​​the airflow channel can be increased, thereby further increasing the exhaust space of the bottom bracket and improving the exhaust effect.

[0011] In some embodiments, the first support rib extends from one end to the other end of the support plate in the length direction, and the width of the first support rib in the width direction of the support plate gradually increases in the direction from the two ends in the length direction of the support plate toward the middle.

[0012] In this embodiment, by arranging the first support ribs to gradually increase their width from both ends in the length direction of the support plate toward the middle, the structural strength of the middle part of the support plate can be increased, thereby effectively increasing the supporting effect of the bottom bracket, thereby effectively reducing the risk of the bottom bracket being crushed and ensuring the smoothness of exhaust; at the same time, the flow speed of the airflow in the airflow channel can be increased, thereby increasing the exhaust effect, thereby reducing the probability of thermal runaway of the battery cell and the risk of cracking of the shell weld due to excessive pressure.

[0013] In some embodiments, in a direction from one end toward the other end in the length direction of the support plate, a side edge of the first support rib facing the airflow channel extends along an arc line protruding toward the airflow channel.

[0014] In this embodiment, by arranging the edge of one side of the first support rib toward the air flow channel to extend along an arc line protruding toward the air flow channel, the generation of eddy currents can be reduced, the occurrence of boundary layer detachment can be reduced, and the air flow speed can be increased, so that the air flow entering the air flow channel can be quickly guided to the position of the explosion-proof valve, thereby quickly reducing the internal pressure of the battery cell, reducing the probability of thermal runaway of the battery cell and the risk of shell weld cracking due to excessive pressure.

[0015] In some embodiments, the one side edge of the first supporting rib extends along an arc line, and the diameter of the arc line is 130 mm-180 mm.

[0016] By setting the diameter of the arc line to 130mm-180mm, this embodiment can prevent the curvature of the first support rib from being too large, which is conducive to the smooth flow of airflow, reduces the resistance during the flow process, and increases the exhaust effect of the airflow; it can also prevent the curvature of the first support rib from being too small, which is conducive to reducing the generation of vortices in the flow boundary layer, thereby increasing the flow speed and thus improving the exhaust effect.

[0017] In some embodiments, in the width direction of the support plate, the width of the first support rib at both ends in the length direction of the support plate is 8 mm-11 mm.

[0018] In this embodiment, by setting the width of the first support rib at both ends of the support plate in the length direction to 8mm-11mm, the structural strength and supporting performance of the first support rib can meet the supporting performance required by the bottom bracket, thereby reducing the risk of the bottom bracket being crushed; at the same time, it can also ensure the flow area of ​​the airflow channel, thereby ensuring the exhaust space and increasing the exhaust effect.

[0019] In some embodiments, in the width direction of the support plate, the maximum width of the first support rib is 12 mm-16 mm.

[0020] In this embodiment, by setting the maximum width of the first support rib to 12 mm-16 mm, the structural strength of the bottom bracket can be increased, the deformation probability and the risk of crushing of the bottom bracket can be reduced, and the probability of thermal runaway of the battery cell due to a blocked exhaust path can be reduced.

[0021] In some embodiments, the support frame further includes two second support ribs, which extend along the length direction of the support plate and are disposed between the two first support ribs, and the two second support ribs are respectively arranged at both ends of the support plate in the length direction.

[0022] By setting the second support rib, this embodiment can increase the support points of the support frame on the support plate, thereby further increasing the structural strength and support strength of the support frame, further reducing the risk of the bottom bracket being crushed, thereby reducing the probability of thermal runaway of the battery cell due to a blocked exhaust path.

[0023] In some embodiments, in the length direction of the support plate, one end of the second support rib is flush with an end edge of the support plate in the length direction.

[0024] In this embodiment, by arranging one end of the second support rib in the length direction of the support plate to be flush with the end edge of the support plate in the length direction, the structural strength of the two ends of the bottom bracket in the length direction can be increased, thereby effectively preventing the airflow inlet from being crushed, allowing the airflow to smoothly enter the airflow channel and be guided along the airflow channel to the explosion-proof valve, and then exhaust the gas to the outside of the battery cell, thereby reducing the occurrence of thermal runaway of the battery cell; at the same time, it can also effectively prevent the formation of a flow stagnation zone between the second support rib and the support plate, ensure the smoothness of the airflow, and thereby improve the exhaust effect.

[0025] In some embodiments, in the length direction of the support plate, the length of the second support rib is 20 mm-30 mm.

[0026] In this embodiment, the length of the second support rib is set to 20mm-30mm, so that the length of the second support rib is not too large, which is beneficial to increase the flow area of ​​the airflow channel, improve the flow space of the airflow, and increase the exhaust effect of the bottom bracket; it also makes the length of the second support rib not too small, so that the support strength of the support frame can meet the structural strength required by the bottom bracket, thereby reducing the risk of the bottom bracket being crushed, and improving the reliability and service life of the battery cell.

[0027] In some embodiments, in the length direction of the support plate, the ratio of the length of the second support rib to the length of the support plate is 0.07-0.12.

[0028] In this embodiment, by setting the ratio of the length of the second support rib to the length of the support plate to 0.07-0.12, the flow area of ​​the airflow channel can be effectively increased, and the exhaust space can be increased, making the exhaust path smoother, thereby accelerating the discharge of gas, reducing the pressure inside the battery cell, and improving the reliability and service life of the battery cell; at the same time, the second support rib can also meet the support strength required by the bottom bracket, which can effectively reduce the risk of the bottom bracket being crushed, and then reduce the probability of exhaust failure of the bottom bracket, improve the exhaust effect, thereby reducing the probability of thermal runaway of the battery cell, and improving the reliability and service life of the battery cell.

[0029] In some embodiments, the end surface of the other end of the second supporting rib is an arc surface that is convex in a direction away from the end edge of the supporting plate.

[0030] By setting the end face of the other end of the second support rib to be a curved surface that is raised in the direction away from the end edge of the support plate, this embodiment can effectively reduce the probability of eddy current generation, thereby increasing the flow rate of the airflow, so that the gas generated inside the battery cell can flow quickly to the explosion-proof valve and be discharged to the outside of the battery cell, thereby effectively reducing the occurrence of thermal runaway of the battery cell.

[0031] In some embodiments, the airflow channel includes a guide section and a confluence area, the guide sections are two in number and are respectively connected to both sides of the confluence area in the length direction of the support plate, and at least one side wall of the guide section in the width direction of the support plate is formed with a guide slope, and in the direction from the guide section toward the confluence area, the guide slopes of the two guide sections extend obliquely toward both sides of the confluence area in the width direction of the support plate.

[0032] By setting the guide section, this embodiment can guide the gas to flow smoothly, make the overall flow more orderly, help to achieve directional flow of gas, and thus increase the smoothness of exhaust. At the same time, by setting the confluence area, the airflow entering from both ends can be gathered at the explosion-proof valve, which can increase the gas content at the explosion-proof valve position, and then increase the gas discharge speed, thereby improving the exhaust effect.

[0033] In some embodiments, the two first supporting ribs are arranged rotationally symmetrically about the center of the supporting plate within the first surface.

[0034] In this embodiment, by arranging two first support ribs rotationally symmetrically about the center of the support plate within the first surface, the two first support ribs can be manufactured by one mold or process, thereby reducing the mold opening cost or the manufacturing cost, thereby reducing the production difficulty and cost of the bottom bracket.

[0035] In some embodiments, the first support rib includes: a first support segment and a second support segment connected sequentially in the length direction of the support plate, at least a portion of a side surface of the first support segment facing the airflow channel is formed as the guide slope, and in the direction from the first support segment toward the second support segment, the guide slope extends obliquely toward another first support rib.

[0036] In this embodiment, by providing a first supporting section and a second supporting section, and forming a guiding slope on the surface of one side of the first supporting section facing the air flow channel, the air flow can form a vortex in the confluence area, thereby accelerating the discharge of gas, thereby effectively reducing the internal pressure of the battery cell and reducing the probability of thermal runaway of the battery cell.

[0037] In some embodiments, the corners between the guiding slope and the end surface of the first supporting rib are rounded.

[0038] This embodiment can effectively reduce the generation of eddy currents at the entrance of the air flow channel by setting a chamfer between the guide slope and the end face of the first support rib, thereby increasing the flow rate and smoothness of the air flow, allowing the gas generated inside the battery cell to flow quickly to the explosion-proof valve and be discharged to the outside of the battery cell, thereby effectively reducing the occurrence of thermal runaway of the battery cell.

[0039] In some embodiments, the fillet radius between the guide slope and the end surface of the first support rib is 2.5 mm-5 mm.

[0040] In this embodiment, the fillet radius between the guide bevel and the end face of the first support rib is set to 2.5mm-5mm, so that the fillet between the guide bevel and the end face of the first support rib is not too large, which is beneficial to the production of the fillet and reduces the impact on the guide bevel; at the same time, it also ensures that the fillet between the guide bevel and the end face of the first support rib is not too small, which is beneficial to the reduction of eddy currents, thereby increasing the flow rate and smoothness of the airflow and improving the exhaust effect.

[0041] In some embodiments, the side surface of the first support segment facing the airflow channel also includes a drainage slope, and the drainage slope is connected to one end of the guide slope facing the second support segment. In the direction from the first support segment toward the second support segment, the drainage slope extends obliquely toward the other side surface of the first support rib away from the airflow channel, and the confluence area is formed between the drainage slopes of the two first support ribs.

[0042] By providing a guide slope, this embodiment can change the original flow trajectory of the airflow, so that the two airflows entering the confluence area move in opposite directions and do not directly collide with each other, thereby further promoting the generation of vortices and accelerating exhaust.

[0043] In some embodiments, the angle between the drainage slope and the length direction of the support plate is greater than the angle between the guide slope and the length direction of the support plate.

[0044] In this embodiment, by setting the angle between the drainage slope and the length direction of the support plate to be larger than the angle between the guide slope and the length direction of the support plate, the range of the confluence area can be limited to be smaller than the range of the guide section, and the range of the confluence area can be limited to the position of the explosion-proof valve, thereby increasing the exhaust effect.

[0045] In some embodiments, the drainage slope is connected to the guide slope in an arc.

[0046] By setting an arc connection between the drainage slope and the guide slope, this embodiment can reduce the generation of vortices at the connection between the drainage slope and the guide slope, thereby increasing the speed of air flow and further accelerating the generation of vortices, so that the air flow can be quickly discharged from the interior of the battery cell, reducing the pressure inside the battery cell and reducing the occurrence of thermal runaway of the battery cell.

[0047] In some embodiments, a side surface of the second supporting section facing the airflow channel is a plane parallel to the length direction of the supporting plate.

[0048] In this embodiment, the side surface of the second support section facing the airflow channel is set to be a plane parallel to the length direction of the support plate. In this way, the production convenience of the support frame can be improved, the production rate of the support frame can be increased, and at the same time, the size of the airflow channel can be easily controlled to ensure the exhaust effect.

[0049] In some embodiments, in the width direction of the support plate, the ratio of the width of the second support segment to the maximum width of the first support segment is 0.25-0.45.

[0050] In this embodiment, by setting the ratio of the width of the second support section to the maximum width of the first support section to 0.25-0.45, the width of the second support section can be not too large, so as to ensure the width of the air flow channel and meet the exhaust requirements of the battery cell; at the same time, the width of the second support section can be not too small, which is beneficial to improving the supporting effect of the support plate, thereby improving the supporting strength of the bottom bracket and effectively reducing the risk of the bottom bracket being crushed.

[0051] In some embodiments, the ratio of the projected area of ​​the support frame within the first surface to the area of ​​the first surface is 0.15-0.4.

[0052] This embodiment sets the ratio of the projection area of ​​the support frame within the first surface to the area of ​​the first surface to 0.15-0.4, which is beneficial to improving the structural strength and structural stability of the bottom bracket, and can effectively prevent the bottom bracket from being crushed; at the same time, it can also limit the flow area of ​​the airflow channel, so that the flow area of ​​the airflow channel can meet the exhaust demand, so that the gas in the battery cell cycle process can be discharged in time, reducing the internal pressure of the battery cell, and thus reducing the probability of thermal runaway of the battery cell, and improving the reliability and service life of the battery cell.

[0053] In some embodiments, in the thickness direction of the support plate, the height of the support frame is 0.6 mm-5 mm.

[0054] In this embodiment, the height of the support frame is set to 0.6mm-5mm in the thickness direction of the support plate, so that the bottom bracket can not only ensure the smooth exhaust of the battery cell, but also reduce the space occupied by the bottom bracket, thereby improving the energy density of the battery cell.

[0055] In some embodiments, in the thickness direction of the support plate, the height of the support frame is 0.6 mm-3 mm.

[0056] In this embodiment, the height of the support frame is set to 0.6mm-3mm in the thickness direction of the support plate, so that the height of the support frame is not too high, which is beneficial to improving the energy density of the battery cell. At the same time, the height of the support frame is not too small, so that the height of the support frame can meet the exhaust requirements, thereby improving the exhaust effect.

[0057] In some embodiments, the battery cell is a lithium iron phosphate battery, and the height of the support frame is 0.6 mm-1 mm; or, the battery cell is a ternary polymer lithium battery, and the height of the support frame is 0.6 mm-3 mm.

[0058] In this embodiment, when the battery cell is a lithium iron phosphate battery, the height of the support frame is set to 0.6mm-1mm, and when the battery cell is a ternary polymer lithium battery, the height of the support frame is set to 0.6mm-3mm. The height of the support frame can be designed according to the type of battery cell, so that the bottom bracket can meet the exhaust requirements while reducing the space occupied by the bottom bracket and improving the energy density of the battery cell.

[0059] In some embodiments, the support plate has a thickness of 0.4 mm to 0.6 mm.

[0060] In this embodiment, by setting the thickness of the support plate to 0.4mm-0.6mm, the support plate can satisfy the support function of the bottom bracket for the electrode assembly while reducing the material used for the support plate, thereby reducing the production difficulty and production cost of the support plate; at the same time, setting the thickness range of the support plate to [0.4mm, 0.6mm] can also reduce the thickness of the bottom bracket, thereby improving the energy density of the battery cell.

[0061] In some embodiments, the bottom bracket is a polypropylene piece, or, the bottom bracket is an aluminum piece.

[0062] In this embodiment, by setting the bottom bracket to be a polypropylene part, the possibility of the bottom bracket being corroded or crushed by the electrolyte can be reduced, thereby improving the reliability and service life of the bottom bracket; at the same time, the production cost of the battery cell can be reduced; by setting the bottom bracket to be an aluminum part, the supporting performance and corrosion resistance of the bottom bracket can be increased while the weight of the bottom bracket can be reduced, thereby reducing the weight of the battery cell, thereby achieving lightweight batteries.

[0063] A battery according to a second aspect of the present invention comprises a battery cell according to the first aspect of the present invention.

[0064] According to the battery of the present invention, the battery cell of the first aspect is provided, thereby improving the overall performance of the battery.

[0065] An electric device according to a third aspect of the present invention comprises a battery according to the second aspect of the present invention.

[0066] According to the electric device of the present invention, the battery of the second aspect is provided, thereby improving the overall performance of the electric device.

[0067] Additional aspects and advantages of the present invention will be given in part in the following description and in part will be obvious from the following description, or will be learned through practice of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0068] Figure 1 is a schematic diagram of a vehicle according to an embodiment of the present invention;

[0069] Figure 2 is a schematic diagram of a battery according to an embodiment of the present invention;

[0070] Figure 3 is an exploded diagram of a battery according to an embodiment of the present invention;

[0071] Figure 4 is an exploded view of a battery cell according to an embodiment of the present invention;

[0072] Figure 5 is a schematic diagram of a bottom bracket according to an embodiment of the present invention;

[0073] Figure 6 yes Figure 5 A schematic diagram from another angle shown in ;

[0074] Figure 7 yes Figure 5 A schematic diagram of the bottom bracket shown in another angle;

[0075] Figure 8 yes Figure 5 A schematic diagram of another angle of the bottom bracket shown in ;

[0076] Fig. 9 is a schematic diagram of a bottom bracket according to another embodiment of the present invention;

[0077] Fig.10 yes Fig. 9 A schematic diagram of another angle of the bottom bracket shown in ;

[0078] Fig.11 yes Fig. 9 A schematic diagram of the bottom bracket shown in another angle;

[0079] Fig.12 yes Fig. 9 A schematic diagram of another angle of the bottom bracket shown in FIG.

[0080] Reference numerals:

[0081] 1. Vehicles;

[0082] 1000. Battery;

[0083] 100. Battery cell;

[0084] 10. bottom bracket; 11. support plate; 12. support frame; 121. first support rib; 1211. first support section; 1212. second support section; 1213. guide slope; 1214. drainage slope; 122. second support rib; 13. air flow channel; 131. guide section; 132. confluence area;

[0085] 20. housing; 21. accommodating chamber;

[0086] 30. Electrode assembly;

[0087] 40. end cover; 50. adapter;

[0088] 200, box body; 201, main box; 202, cover plate;

[0089] 2000, controller; 3000, motor. DETAILED DESCRIPTION

[0090] The following embodiments of the technical solution of the present invention are described in detail in conjunction with the accompanying drawings. The following embodiments are only used to more clearly illustrate the technical solution of the present invention, and are therefore only used as examples, and cannot be used to limit the protection scope of the present invention.

[0091] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by technicians in the technical field to which the present invention belongs; the terms used herein are only for the purpose of describing specific embodiments and are not intended to limit the present invention; the terms "including" and "having" in the specification and claims of the present invention and the above-mentioned figure descriptions and any variations thereof are intended to cover non-exclusive inclusions.

[0092] In the description of the embodiments of the present invention, the technical terms "first", "second", etc. are only used to distinguish different objects, and cannot be understood as indicating or implying relative importance or implicitly indicating the number, specific order or primary and secondary relationship of the indicated technical features. In the description of the embodiments of the present invention, the meaning of "multiple" is more than two, unless otherwise clearly and specifically defined.

[0093] Reference to "embodiments" herein means that a particular feature, structure, or characteristic described in conjunction with the embodiments may be included in at least one embodiment of the present invention. The appearance of the phrase in various places in the specification does not necessarily refer to the same embodiment, nor is it an independent or alternative embodiment that is mutually exclusive with other embodiments. It is explicitly and implicitly understood by those skilled in the art that the embodiments described herein may be combined with other embodiments.

[0094] In the description of the embodiments of the present invention, the term "and / or" is only a description of the association relationship of associated objects, indicating that three relationships may exist. For example, A and / or B may represent: A exists alone, A and B exist at the same time, and B exists alone. In addition, the character " / " in this article generally indicates that the associated objects before and after are in an "or" relationship.

[0095] In the description of the embodiments of the present invention, the term "plurality" refers to more than two (including two).

[0096] In the description of the embodiments of the present invention, the orientations or positional relationships indicated by technical terms such as "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "axial", "radial", and "circumferential" are based on the orientations or positional relationships shown in the accompanying drawings and are only for the convenience of describing the embodiments of the present invention and simplifying the description, and do not indicate or imply that the referred device or element must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as limiting the embodiments of the present invention.

[0097] In the description of the embodiments of the present invention, unless otherwise clearly specified and limited, technical terms such as "installed", "connected", "connected", "fixed" and the like should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements. For ordinary technicians in this field, the specific meanings of the above terms in the embodiments of the present invention can be understood according to specific circumstances.

[0098] At present, from the perspective of market development, the application of power batteries is becoming more and more extensive. Power batteries are not only used in energy storage power systems such as hydropower, thermal power, wind power and solar power stations, but also widely used in electric vehicles such as electric bicycles, electric motorcycles, electric cars, as well as military equipment and aerospace and other fields. With the continuous expansion of the application field of power batteries, the market demand is also constantly expanding.

[0099] At present, ultra-thin diaphragms are introduced in the production of battery cells. The use of ultra-thin diaphragms reduces the volume of electrode assemblies, reduces group margins, and increases energy density, which in turn provides space for increasing the capacity of electrode assemblies. As the capacity of electrode assemblies increases, the gas production of battery cells also increases, and the probability of thermal runaway of battery cells and the risk of shell weld cracking caused by excessive pressure also increase. In order to prevent the released gas and particulate matter from entering the passenger compartment, an explosion-proof valve is currently set at the bottom of the battery cell. However, this solution is prone to poor exhaust, making it difficult for gas to flow to the explosion-proof valve for timely discharge, further increasing the probability of thermal runaway of the battery cell.

[0100] In order to solve the problem of thermal runaway and shell weld cracking caused by the inability to discharge gas smoothly due to the explosion-proof valve located at the bottom of the battery cell during the cycle of the battery cell, research has found that an exhaust channel can be added at the bottom of the battery cell to ensure the exhaust space for the gas so that the gas can be discharged smoothly, thereby reducing the internal pressure of the battery cell and reducing the occurrence of thermal runaway.

[0101] Based on the above considerations, in order to solve the problem of thermal runaway and shell weld cracking caused by the inability to discharge gas smoothly due to the explosion-proof valve arranged at the bottom of the battery monomer during the recycling process of the battery monomer, a battery monomer is designed. By setting a bottom bracket, multiple first support ribs of the bottom bracket are respectively arranged on at least one side edge in the width direction of the support plate, and the first support ribs, the support plate and the bottom wall of the accommodating cavity jointly define an air flow channel, so that the exhaust space of the gas can be increased, the direction of the gas can be guided, and the gas can be quickly discharged to the explosion-proof valve position of the battery monomer. As a result, the gas generated by the battery monomer can have a larger discharge space, and then the airflow in the battery monomer cycle process can be quickly discharged, so that the internal pressure of the battery monomer can be quickly reduced, and the probability of thermal runaway can be reduced.

[0102] When the battery cell is recycled, a large amount of gas is generated inside the battery cell. The gas can enter the air flow channel through the two ends of the first support rib in the length direction, and then be discharged to the explosion-proof valve through the air flow channel. Therefore, the bottom bracket of the present application can improve the exhaust condition inside the battery cell, reduce the internal pressure of the battery cell, and further reduce the probability of thermal runaway of the battery cell and the risk of shell weld cracking caused by excessive pressure.

[0103] The battery cell disclosed in the embodiments of the present application can be used in electrical devices that use batteries as power sources or various energy storage systems that use batteries as energy storage elements. Electrical devices can be, but are not limited to, mobile phones, tablets, laptops, electric toys, electric tools, battery cars, electric cars, ships, spacecraft, etc. Among them, electric toys can include fixed or mobile electric toys, such as game consoles, electric car toys, electric ship toys, and electric airplane toys, etc., and spacecraft can include airplanes, rockets, space shuttles, and spacecraft, etc.

[0104] For the convenience of description, the following embodiments are described by taking a vehicle 1 as an example of an electrical device according to an embodiment of the present invention.

[0105] Reference Figure 1 , Figure 1 Schematic diagram of vehicle 1 provided for some embodiments of the present invention. Vehicle 1 may be a fuel vehicle, a gas vehicle or a new energy vehicle, and the new energy vehicle may be a pure electric vehicle, a hybrid vehicle or an extended-range vehicle, etc. A battery 1000 is provided inside the vehicle 1, and the battery 1000 may be provided at the bottom, the head or the tail of the vehicle 1. The battery 1000 may be used to power the vehicle 1, for example, the battery 1000 may be used as an operating power source for the vehicle 1. The vehicle 1 may also include a controller 2000 and a motor 3000, and the controller 2000 is used to control the battery 1000 to power the motor 3000, for example, for the starting, navigation and working power requirements of the vehicle during driving.

[0106] In some embodiments of the present application, the battery 1000 can not only serve as an operating power source for the vehicle 1 , but also serve as a driving power source for the vehicle 1 , replacing or partially replacing fuel or natural gas to provide driving power for the vehicle 1 .

[0107] Reference Figure 2 and Figure 3 , Figure 2 is a schematic diagram of a battery 1000 according to some embodiments of the present invention, Figure 3 1 is an exploded view of a battery 1000 according to some embodiments of the present invention. The battery 1000 includes a box 200 and a battery cell 100, the box 200 has a cavity, and the battery cell 100 is accommodated in the cavity of the box 200. The box 200 is used to provide a storage space for the battery cell 100, and the box 200 can adopt a variety of structures. In some embodiments, the box 200 may include a first part (such as the main box 201 described below) and a second part (such as the cover plate 202 described below), the first part and the second part cover each other, and the first part and the second part jointly define a storage space for accommodating the battery cell 100. The second part may be a hollow structure with one end open, the first part may be a plate-like structure, the first part covers the open side of the second part, so that the first part and the second part jointly define a storage space; the first part and the second part may also be hollow structures with one side open, and the open side of the first part covers the open side of the second part. Of course, the box 200 formed by the first part and the second part may be in a variety of shapes, such as a cylinder, a cuboid, etc.

[0108] In the battery 1000, there may be multiple battery cells 100, and the multiple battery cells 100 may be connected in series, in parallel, or in a mixed connection. A mixed connection means that the multiple battery cells 100 are both connected in series and in parallel. The multiple battery cells 100 may be directly connected in series, in parallel, or in a mixed connection, and then the whole formed by the multiple battery cells 100 is accommodated in the box 200; of course, the battery 1000 may also be a battery module formed by connecting multiple battery cells 100 in series, in parallel, or in a mixed connection, and then the multiple battery modules are connected in series, in parallel, or in a mixed connection to form a whole, and accommodated in the box 200. The battery 1000 may also include other structures, for example, the battery 1000 may also include a busbar component for realizing electrical connection between the multiple battery cells 100.

[0109] Each battery cell 100 may be a secondary battery or a primary battery, or a lithium-sulfur battery, a sodium-ion battery, or a magnesium-ion battery, but is not limited thereto. The battery cell 100 may be cylindrical, flat, rectangular, or in other shapes.

[0110] Reference Figure 4 , Figure 4Schematic diagram of a battery cell 100 provided in some embodiments of the present invention, wherein the battery cell 100 refers to the smallest unit constituting a battery 1000. Figure 4 As shown, the battery cell 100 includes an end cap 40, a shell 20, an electrode assembly 30, a switching plate 50, a first insulating member, a bottom bracket 10 and other functional components.

[0111] The end cap 40 refers to a component that covers the opening of the shell 20 to isolate the internal environment of the battery cell 100 from the external environment. Without limitation, the shape of the end cap 40 can be adapted to the shape of the shell 20 to match the shell 20. Optionally, the end cap 40 can be made of a material with a certain hardness and strength (such as aluminum alloy), so that the end cap 40 is not easily deformed when squeezed and collided, so that the battery cell 100 can have a higher structural strength and the safety performance can also be improved. Functional components such as output terminals can be provided on the end cap 40. The output terminal can be used to electrically connect to the electrode assembly 30 for outputting or inputting electrical energy of the battery cell 100. In some embodiments, the end cap 40 can also be provided with an explosion-proof valve for releasing the internal pressure when the internal pressure or temperature of the battery cell 100 reaches a threshold. The material of the end cap 40 can also be a variety of materials, including but not limited to: copper, iron, aluminum, stainless steel, aluminum alloy, plastic, etc. In some embodiments, a first insulating member and a transfer sheet 50 may be further disposed on the inner side of the end cap 40. The first insulating member may be used to isolate the electrical connection components in the housing 20 from the end cap 40 to reduce the risk of short circuit; the transfer sheet 50 is connected to the tab for current transmission. Exemplarily, the first insulating member may be plastic, rubber, etc.

[0112] The shell 20 is a component used to cooperate with the end cap 40 to form the internal environment of the battery cell 100, wherein the formed internal environment can be used to accommodate the electrode assembly 30 and other components. The shell 20 and the end cap 40 can be independent components, and an opening can be set on the shell 20, and the internal environment of the battery cell 100 is formed by covering the opening with the end cap 40 at the opening. Without limitation, the end cap 40 and the shell 20 can also be integrated. Specifically, the end cap 40 and the shell 20 can form a common connection surface before other components are put into the shell, and when the interior of the shell 20 needs to be encapsulated, the end cap 40 is covered with the shell 20. The shell 20 can be of various shapes and sizes, such as a rectangular parallelepiped, a cylindrical shape, a hexagonal prism, etc. Specifically, the shape of the shell 20 can be determined according to the specific shape and size of the electrode assembly 30. The material of the shell 20 can be various, including but not limited to: copper, iron, aluminum, stainless steel, aluminum alloy, plastic, etc.

[0113] The electrode assembly 30 is a component in the battery cell 100 where electrochemical reactions occur. One or more electrode assemblies 30 may be included in the housing 20. The electrode assembly 30 is mainly formed by winding or stacking positive and negative electrode sheets, and a separator is usually provided between the positive and negative electrode sheets. The parts of the positive and negative electrode sheets with active materials constitute the main body of the electrode assembly 30, and the parts of the positive and negative electrode sheets without active materials each constitute a tab. The positive tab and the negative tab may be located together at one end of the main body or respectively at both ends of the main body. During the charge and discharge process of the battery 1000, the positive active material and the negative active material react with the electrolyte, and the tabs connect the electrode terminals to form a current loop.

[0114] The positive electrode sheet includes a positive electrode current collector and a positive electrode active material layer, the positive electrode active material layer is coated on the surface of the positive electrode current collector, the positive electrode current collector not coated with the positive electrode active material layer protrudes from the positive electrode current collector coated with the positive electrode active material layer, and the positive electrode current collector not coated with the positive electrode active material layer serves as a positive electrode tab. Taking lithium-ion batteries as an example, the material of the positive electrode current collector can be aluminum, and the positive electrode active material can be lithium cobalt oxide, lithium iron phosphate, ternary lithium or lithium manganese oxide, etc.

[0115] The negative electrode sheet includes a negative electrode current collector and a negative electrode active material layer. The negative electrode active material layer is coated on the surface of the negative electrode current collector. The negative electrode current collector not coated with the negative electrode active material layer protrudes from the negative electrode current collector coated with the negative electrode active material layer. The negative electrode current collector not coated with the negative electrode active material layer serves as a negative electrode tab. The material of the negative electrode current collector can be copper, and the negative electrode active material can be carbon or silicon, etc. In order to ensure that a large current passes without melting, the number of positive electrode tabs is multiple and stacked together, and the number of negative electrode tabs is multiple and stacked together.

[0116] The material of the diaphragm can be PP (polypropylene) or PE (polyethylene).

[0117] Reference below Figure 4-Figure 11 A battery cell 100 according to an embodiment of the first aspect of the present invention is described. Figure 4 is an exploded view of a battery cell 100 according to some embodiments of the present invention, Figure 5 is a schematic diagram of a bottom bracket 10 according to some embodiments of the present invention, Figure 6 yes Figure 5 The bottom bracket 10 is shown in another angle. Figure 6 yes Figure 5 The bottom bracket 10 is shown in another angle diagram. Figure 8 yes Figure 5 A schematic diagram of the bottom bracket 10 at another angle is shown. Fig. 9 is a schematic diagram of a bottom bracket 10 according to another embodiment of the present invention, Fig.10 yes Fig. 9 A schematic diagram of the bottom bracket 10 from another angle is shown in FIG. Fig.11 yes Fig. 9 A schematic diagram of the bottom bracket 10 at another angle is shown in FIG. Fig.12 yes Fig. 9 FIG. 1 is a schematic diagram of the bottom bracket 10 at another angle shown in FIG.

[0118] The embodiment of the present invention provides a battery cell 100, such as Figure 4-Figure 5 As shown, the battery cell 100 includes: a shell 20, a bottom bracket 10 and an electrode assembly 30, the shell 20 defines a receiving chamber 21, and an explosion-proof valve is provided at the bottom of the shell 20; the bottom bracket 10 is arranged on the bottom wall of the receiving chamber 21, and the bottom bracket 10 includes: a support plate 11 and a support frame 12, and the side surface of the support plate 11 facing the bottom wall of the receiving chamber 21 is a first surface; the support frame 12 includes at least one first support rib 121, and the first support rib 121 is arranged on the first surface and along the length direction of the support plate 11 (for example Figure 5 At least one first support rib 121 is provided on the first surface and is arranged respectively on the width direction (eg, Figure 5 At least one side edge of the support plate 11 (from the front to the rear direction shown in the figure), the first support rib 121, the first surface and the bottom wall of the accommodating cavity 21 define an air flow channel 13 connected to the explosion-proof valve; the electrode assembly 30 is arranged in the accommodating cavity 21 and supported on the second surface of the support plate 11, and the first surface and the second surface are arranged opposite to each other in the thickness direction of the support plate 11.

[0119] Specifically, the housing 20 is mainly used to isolate the inside of the battery cell 100 from the outside, effectively preventing the inside of the battery cell 100 from communicating with the outside, thereby improving the reliability of the battery cell 100. The bottom bracket 10 and the bottom wall of the accommodating cavity 21 together define an airflow channel 13, which can guide the gas in the accommodating cavity 21 to the explosion-proof valve through the airflow channel 13 and discharge it through the explosion-proof valve, thereby effectively reducing the pressure inside the battery cell 100, thereby reducing the probability of thermal runaway of the battery cell 100.

[0120] The support plate 11 can be a horizontally arranged rectangular plate, the second surface of the support plate 11 is connected to the electrode assembly 30, and the first surface of the support plate 11 is abutted against the bottom wall of the accommodating cavity 21 through the support frame 12. Therefore, the support plate 11 and the electrode assembly 30 are in surface contact, which can increase the contact area between the bottom bracket 10 and the electrode assembly 30, and further effectively prevent the damage of the electrode assembly 30 or the bottom bracket 10 caused by the expansion and extrusion of the bottom bracket 10 by the electrode assembly 30, thereby improving the reliability of the battery cell 100.

[0121] The first support rib 121 can be formed as a strip-shaped protrusion, one side of the first support rib 121 is connected to the support plate 11, and the other side extends toward the bottom wall of the accommodating cavity 21 and abuts against the bottom wall of the accommodating cavity 21. The first support rib 121 mainly plays a supporting role, which can form a certain distance between the support plate 11 and the bottom wall of the accommodating cavity 21, thereby limiting the airflow channel 13 and realizing smooth exhaust.

[0122] The support frame 12 includes at least one first support rib 121. For example, the number of the first support ribs 121 can be one, two, three or more. At least one first support rib 121 is provided on the first surface and is respectively arranged on at least one side edge of the support plate 11 in the width direction. That is to say, the first support rib 121 can be arranged on one side edge of the support plate 11, or on both side edges of the support plate 11. In this way, the first support rib 121 can avoid the explosion-proof valve position, so that the airflow channel 13 is connected with the explosion-proof valve, and the gas generated inside the battery cell 100 can flow to the explosion-proof valve through the airflow channel 13 and be discharged through the explosion-proof valve; at the same time, the first support rib 121 is arranged on the edge of the support plate 11, which can also increase the flow area of ​​the airflow channel 13, thereby increasing the exhaust space of the bottom bracket 10 and improving the exhaust effect. When the battery cell 100 is recycled, a large amount of gas is generated inside the battery cell 100. The gas can enter the air flow channel 13 through the two ends of the first support rib 121 in the length direction, and then be drained to the explosion-proof valve through the air flow channel 13 for discharge. Therefore, the bottom bracket 10 of the present application can improve the exhaust condition inside the battery cell 100, reduce the internal pressure of the battery cell 100, and further reduce the probability of thermal runaway of the battery cell 100 and the risk of cracking of the weld of the shell 20 caused by excessive pressure.

[0123] According to the battery cell 100 of the embodiment of the present invention, by providing the air flow channel 13 jointly defined by the bottom bracket 10 and the bottom wall of the accommodating cavity 21, a larger discharge space can be formed inside the battery cell 100, so that a large amount of gas generated by the battery cell 100 during the cycle process can be guided to the explosion-proof valve through the air flow channel 13 and discharged through the explosion-proof valve, thereby improving the exhaust effect of the battery cell 100, effectively reducing the internal pressure of the battery cell 100, and reducing the probability of thermal runaway of the battery cell 100 and the risk of cracking of the weld of the shell 20 caused by excessive pressure.

[0124] According to some embodiments of the present invention, the number of the first support ribs 121 is two, and the two first support ribs 121 are respectively arranged on both side edges of the support plate 11 in the width direction, and at least parts of the two first support ribs 121 are respectively flush with the both side edges of the support plate 11 in the width direction.

[0125] That is to say, parts of the two first support ribs 121 may be flush with the two side edges of the support plate 11 in the width direction, or all of the two first support ribs 121 may be flush with the two side edges of the support plate 11 in the width direction.

[0126] In the embodiment of the present invention, the two first support ribs 121 are respectively arranged on the two side edges of the support plate 11 in the width direction, and at least parts of the two first support ribs 121 are respectively flush with the two side edges of the support plate 11 in the width direction. Therefore, the bottom bracket 10 in the embodiment of the present invention can reduce the gap generated at the edge of the first support rib 121 and the support plate 11, and then, the probability of forming a flow stagnation zone at the edge of the first support rib 121 and the support plate 11 can be further reduced, and the bulging phenomenon caused by the gathering of airflow at the connection between the first support rib 121 and the support plate 11 can be effectively reduced, so that a large amount of gas can enter the airflow channel 13 from both ends of the airflow channel 13, thereby improving the exhaust effect; at the same time, the cross-sectional area of ​​the airflow channel 13 can also be increased, and then the exhaust space of the bottom bracket 10 can be further increased, thereby improving the exhaust effect.

[0127] In this embodiment, two first support ribs 121 are provided, and at least parts of the two first support ribs 121 are flush with the two side edges of the support plate 11 in the width direction, which can effectively reduce the probability of flow stagnation areas being formed at the edges of the first support ribs 121 and the support plate 11, and effectively reduce the bulging phenomenon caused by the gathering of airflow at the connection between the first support ribs 121 and the support plate 11, so that a large amount of gas can enter the airflow channel 13 from both ends of the airflow channel 13, thereby improving the exhaust effect; at the same time, the cross-sectional area of ​​the airflow channel 13 can also be increased, thereby further increasing the exhaust space of the bottom bracket 10 and improving the exhaust effect.

[0128] According to some embodiments of the present invention, Figure 5 As shown, the first support rib 121 extends from one end to the other end of the support plate 11 in the length direction, and the width of the first support rib 121 in the width direction of the support plate 11 gradually increases in the direction from the two ends in the length direction of the support plate 11 toward the middle.

[0129] It can be understood that the width of the first support rib 121 increases first and then decreases in the length direction of the support plate 11. In this way, the width of the middle portion of the first support rib 121 can be made larger, thereby increasing the structural strength of the middle portion of the support plate 11, thereby effectively increasing the supporting effect of the bottom bracket 10, thereby effectively reducing the risk of the bottom bracket 10 being crushed and ensuring smooth exhaust.

[0130] At the same time, an air flow channel 13 is defined between the two first support ribs 121, whereby the cross-sectional area of ​​the air flow channel 13 gradually decreases in the direction toward the middle on both sides in the length direction of the support plate 11, that is, the air flow channel 13 is reduced in diameter, thereby increasing the flow speed of the air flow in the air flow channel 13 and further increasing the exhaust effect, thereby reducing the probability of thermal runaway of the battery cell 100 and the risk of cracking of the weld of the shell 20 caused by excessive pressure.

[0131] In this embodiment, by setting the first support ribs 121 to gradually increase in width from both ends of the support plate 11 in the length direction toward the middle, the structural strength of the middle part of the support plate 11 can be increased, and the supporting effect of the bottom bracket 10 can be effectively increased, thereby effectively reducing the risk of the bottom bracket 10 being crushed and ensuring the smoothness of exhaust; at the same time, the flow speed of the airflow in the airflow channel 13 can be increased, thereby increasing the exhaust effect, thereby reducing the probability of thermal runaway of the battery cell 100 and the risk of cracking of the weld of the shell 20 caused by excessive pressure.

[0132] According to some embodiments of the present invention, Figure 5 As shown, in the direction from one end toward the other end in the length direction of the support plate 11 , one side edge of the first support rib 121 facing the air flow channel 13 extends along an arc line protruding toward the air flow channel 13 .

[0133] Among them, the side edge of the first support rib 121 facing the air flow channel 13 extends along an arc, and the arc-shaped edge can play a drainage role, which can reduce the generation of eddy currents at the surface position of the first support rib 121, and further reduce the occurrence of boundary layer detachment, thereby increasing the air flow speed, so that the air flow entering the air flow channel 13 can be quickly guided to the explosion-proof valve position, thereby quickly reducing the internal pressure of the battery cell 100, reducing the probability of thermal runaway of the battery cell 100 and the risk of cracking of the shell 20 weld due to excessive pressure.

[0134] In this embodiment, by setting the side edge of the first support rib 121 toward the air flow channel 13 to extend along an arc protruding toward the air flow channel 13, the generation of eddy currents can be reduced, the occurrence of boundary layer detachment can be reduced, and the air flow speed can be increased, so that the air flow entering the air flow channel 13 can be quickly guided to the position of the explosion-proof valve, thereby quickly reducing the internal pressure of the battery cell 100, reducing the probability of thermal runaway of the battery cell 100 and the risk of cracking of the weld of the shell 20 caused by excessive pressure.

[0135] According to some embodiments of the present invention, Figure 5 As shown, one side edge of the first supporting rib 121 extends along an arc line, and the diameter of the arc line is 130 mm-180 mm.

[0136] Among them, the arc line has a simple structure and good smoothness, which is conducive to the production of the first support rib 121 and the guidance of the airflow. Then, one side edge of the first support rib 121 extends along the arc line, which can further improve the exhaust effect of the airflow.

[0137] For example, the diameter of the arc line may be 130 mm, 140 mm, 150 mm, 160 mm, 170 mm or 180 mm.

[0138] Preferably, the diameter of the arc line is 150 mm.

[0139] By setting the diameter of the arc line to 130mm-180mm, this embodiment can prevent the curvature of the first support rib 121 from being too large, which is conducive to the smooth flow of airflow, reduces the resistance during the flow process, and increases the exhaust effect of the airflow; it can also prevent the curvature of the first support rib 121 from being too small, which is conducive to reducing the generation of vortices in the flow boundary layer, thereby increasing the flow speed and thus improving the exhaust effect.

[0140] According to some embodiments of the present invention, Figure 5 As shown, in the width direction of the support plate 11 , the widths of the first support ribs 121 at both ends in the length direction of the support plate 11 are 8 mm-11 mm.

[0141] For example, in the width direction of the support plate 11 , the widths of the first support ribs 121 at both ends in the length direction of the support plate 11 may be 8 mm, 9 mm, 10 mm or 11 mm.

[0142] In this embodiment, by setting the width of the first support rib 121 at both ends of the support plate 11 in the length direction to 8mm-11mm, the structural strength and supporting performance of the first support rib 121 can meet the supporting performance required by the bottom bracket 10, thereby reducing the risk of the bottom bracket 10 being crushed; at the same time, it can also ensure the flow area of ​​the airflow channel 13, thereby ensuring the exhaust space and increasing the exhaust effect.

[0143] According to some embodiments of the present invention, Figure 5 As shown, in the width direction of the support plate 11 , the maximum width of the first support rib 121 is 12 mm-16 mm.

[0144] For example, in the width direction of the support plate 11 , the maximum width of the first support rib 121 may be 12 mm, 13 mm, 14 mm, 15 mm or 16 mm.

[0145] Preferably, in the width direction of the support plate 11 , the maximum width of the first support rib 121 is 14 mm.

[0146] In this embodiment, by setting the maximum width of the first support rib 121 to 12 mm-16 mm, the structural strength of the bottom bracket 10 can be increased, the deformation probability and the risk of crushing of the bottom bracket 10 can be reduced, and the probability of thermal runaway of the battery cell 100 caused by a blocked exhaust path can be reduced.

[0147] According to some embodiments of the present invention, Figure 5 As shown, the support frame 12 also includes two second support ribs 122, which extend along the length direction of the support plate 11 and are arranged between the two first support ribs 121. The two second support ribs 122 are respectively arranged at both ends of the support plate 11 in the length direction.

[0148] By setting the second support rib 122, this embodiment can increase the support points of the support frame 12 on the support plate 11, thereby further increasing the structural strength and support strength of the support frame 12, and further reducing the risk of the bottom bracket 10 being crushed, thereby reducing the probability of thermal runaway of the battery cell 100 due to a blocked exhaust path.

[0149] According to some embodiments of the present invention, Figure 5 As shown, in the length direction of the support plate 11 , one end of the second support rib 122 is flush with the end edge of the support plate 11 in the length direction.

[0150] In this embodiment, by arranging one end of the second support rib 122 in the length direction of the support plate 11 to be flush with the end edge of the support plate 11 in the length direction, the structural strength of the two ends of the bottom bracket 10 in the length direction can be increased, thereby effectively preventing the airflow inlet from being crushed, allowing the airflow to smoothly enter the airflow channel 13 and be guided to the explosion-proof valve along the airflow channel 13, and then the gas is discharged to the outside of the battery cell 100, thereby reducing the occurrence of thermal runaway of the battery cell 100; at the same time, it can also effectively prevent the formation of a flow stagnation zone between the second support rib 122 and the support plate 11, ensure the smoothness of the airflow, and thus improve the exhaust effect.

[0151] According to some embodiments of the present invention, Figure 5 As shown, in the length direction of the support plate 11, the length of the second support rib 122 is 20mm-30mm.

[0152] For example, in the length direction of the support plate 11, the length of the second support rib 122 may be 20 mm, 22 mm, 24 mm, 26 mm, 28 mm or 30 mm.

[0153] In this embodiment, the length of the second support rib 122 is set to 20mm-30mm, so that the length of the second support rib 122 is not too large, which is beneficial to increase the flow area of ​​the airflow channel 13, improve the flow space of the airflow, and increase the exhaust effect of the bottom bracket 10; it also makes the length of the second support rib 122 not too small, so that the supporting strength of the support frame 12 can meet the structural strength required by the bottom bracket 10, thereby reducing the risk of the bottom bracket 10 being crushed, and improving the reliability and service life of the battery cell 100.

[0154] According to some embodiments of the present invention, Figure 5 As shown, in the length direction of the support plate 11, the ratio of the length of the second support rib 122 to the length of the support plate 11 is 0.07-0.12.

[0155] For example, in the length direction of the support plate 11 , the ratio of the length of the second support rib 122 to the length of the support plate 11 may be 0.07, 0.08, 0.09, 0.1, 0.11 or 0.12.

[0156] In this embodiment, by setting the ratio of the length of the second support rib 122 to the length of the support plate 11 to 0.07-0.12, the flow area of ​​the airflow channel 13 can be effectively increased, and the exhaust space can be increased, making the exhaust path smoother, thereby accelerating the discharge of gas, reducing the pressure inside the battery cell 100, and improving the reliability and service life of the battery cell 100; at the same time, the second support rib 122 can also meet the support strength required by the bottom bracket 10, which can effectively reduce the risk of the bottom bracket 10 being crushed, and then reduce the probability of exhaust failure of the bottom bracket 10, improve the exhaust effect, thereby reducing the probability of thermal runaway of the battery cell 100, and improving the reliability and service life of the battery cell 100.

[0157] According to some embodiments of the present invention, Figure 5 As shown, the end surface of the other end of the second supporting rib 122 is a curved surface that is convex in a direction away from the end edge of the supporting plate 11 .

[0158] Specifically, the other end of the second support rib 122 refers to the end facing the middle of the support plate 11, wherein the arc surface can guide the gas, thereby effectively reducing the probability of eddy current generation, and then increasing the flow rate of the airflow, so that the gas generated inside the battery cell 100 can flow quickly to the explosion-proof valve and be discharged to the outside of the battery cell 100, thereby effectively reducing the probability of thermal runaway of the battery cell 100.

[0159] By setting the end face of the other end of the second support rib 122 to be a curved surface that is raised in the direction away from the end edge of the support plate 11, the probability of eddy current generation can be effectively reduced in this embodiment, thereby increasing the flow rate of the airflow, so that the gas generated inside the battery cell 100 can flow quickly to the explosion-proof valve and be discharged to the outside of the battery cell 100, thereby effectively reducing the occurrence of thermal runaway of the battery cell 100.

[0160] According to some embodiments of the present invention, Fig. 9 As shown, the air flow channel 13 includes a guide section 131 and a confluence area 132. The number of the guide sections 131 is two and they are respectively connected to the confluence area 132 in the length direction of the support plate 11 (for example Fig. 9 The guide section 131 is disposed on both sides of the support plate 11 in the width direction (eg, from left to right). Fig. 9 At least one side wall (in the direction from front to rear as shown) is formed with a guide slope 1213, and in the direction from the guide section 131 toward the confluence area 132, the guide slopes 1213 of the two guide sections 131 extend obliquely toward both sides of the confluence area 132 in the width direction of the support plate 11.

[0161] Specifically, the guide section 131 mainly guides the airflow, guides the gas to flow smoothly, and makes the overall flow more orderly; the confluence area 132 is mainly used to converge the airflow, so that the airflow gathers at the explosion-proof valve, and then discharges through the explosion-proof valve. Among them, the explosion-proof valve is arranged on the bottom wall of the battery cell 100 shell 20, and is arranged corresponding to the confluence area 132, which is conducive to increasing the exhaust effect of the airflow.

[0162] It is understandable that the guide section 131 may be formed with a guide slope 1213 on one side in the width direction of the support plate 11, or may be formed with guide slopes 1213 on both sides in the width direction of the support plate 11. The guide slope 1213 may limit the direction of movement of the airflow, making the overall flow more orderly, and helping to achieve directional flow of the gas.

[0163] By setting the guide section 131, this embodiment can guide the gas to flow smoothly, make the overall flow more orderly, help to achieve directional flow of gas, and thus increase the smoothness of exhaust. At the same time, by setting the confluence area 132, the airflow entering from both ends can be gathered at the explosion-proof valve, which can increase the gas content at the explosion-proof valve position, and then increase the gas discharge speed, thereby improving the exhaust effect.

[0164] According to some embodiments of the present invention, Fig. 9 As shown, the two first support ribs 121 are arranged rotationally symmetrically about the center of the support plate 11 in the first surface.

[0165] It can be understood that one of the support ribs can overlap with the other support rib after rotating 180° around the center of the support plate 11 in the first surface. In other words, the two first support ribs 121 have exactly the same shape and size, so that the two first support ribs 121 can be made by one mold or process, thereby reducing the mold opening cost or the manufacturing cost, thereby reducing the production difficulty and cost of the bottom bracket 10.

[0166] In this embodiment, by arranging two first support ribs 121 in rotational symmetry about the center of the support plate 11 within the first surface, the two first support ribs 121 can be manufactured by one mold or process, thereby reducing the mold opening cost or the manufacturing cost, thereby reducing the production difficulty and cost of the bottom bracket 10.

[0167] According to some embodiments of the present invention, Fig. 9 As shown, the first support rib 121 includes: a first support segment 1211 and a second support segment 1212 which are sequentially connected in the length direction of the support plate 11, and at least a portion of a side surface of the first support segment 1211 facing the airflow channel 13 is formed as a guide slope 1213, and in the direction from the first support segment 1211 toward the second support segment 1212, the guide slope 1213 extends obliquely toward the other first support rib 121.

[0168] It is understandable that the surface of one side of the first support section 1211 facing the airflow channel 13 may be partially formed as a guide slope 1213, or may be entirely formed as a guide slope 1213. The guide slope 1213 extends obliquely from the edge in the length direction of the support plate 11 to the center of the support plate 11, which is conducive to guiding the airflow from the inlet of the airflow channel 13 to the explosion-proof valve, thereby achieving directional flow of the airflow and increasing the smoothness of the exhaust.

[0169] At the same time, the two first support ribs 121 are centrally symmetrical, and further, the two guide slopes 1213 have the same inclination direction and inclination angle in the length direction of the support plate 11, so that the internal airflows of the two air guide sections flow in opposite directions. In addition, since a confluence area 132 is formed between the two air guide sections, further, the two airflows flow in a staggered manner when flowing to the confluence area 132, and a vortex is formed in the confluence area 132, thereby accelerating the discharge of the gas.

[0170] In this embodiment, by setting the first support section 1211 and the second support section 1212, and forming a guide slope 1213 on the side surface of the first support section 1211 facing the air flow channel 13, the air flow can form a vortex in the confluence area 132, thereby accelerating the discharge of gas, thereby effectively reducing the internal pressure of the battery cell 100 and reducing the probability of thermal runaway of the battery cell 100.

[0171] According to some embodiments of the present invention, Fig. 9 As shown, the corner between the guiding inclined surface 1213 and the end surface of the first supporting rib 121 is rounded.

[0172] It can be understood that the connection between the guide slope 1213 and the end surface of the first support rib 121 is formed as an arc surface, wherein the arc surface can guide the airflow entering the airflow channel 13, so that the airflow can smoothly enter the airflow channel 13, thereby effectively reducing the generation of vortices at the entrance of the airflow channel 13, improving the flow rate of the airflow and the smoothness of the airflow flow, so that the gas generated inside the battery cell 100 can flow quickly to the explosion-proof valve and be discharged to the outside of the battery cell 100, thereby effectively reducing the occurrence of thermal runaway of the battery cell 100.

[0173] By providing a rounded corner between the guide slope 1213 and the end surface of the first support rib 121, this embodiment can effectively reduce the generation of eddy currents at the entrance of the airflow channel 13, increase the flow rate and smoothness of the airflow, and enable the gas generated inside the battery cell 100 to flow quickly to the explosion-proof valve and be discharged to the outside of the battery cell 100, thereby effectively reducing the occurrence of thermal runaway of the battery cell 100.

[0174] According to some embodiments of the present invention, the fillet radius between the guiding slope 1213 and the end surface of the first supporting rib 121 is 2.5 mm-5 mm.

[0175] For example, the fillet radius between the guiding slope 1213 and the end surface of the first supporting rib 121 may be 2.5 mm, 3 mm, 3.5 mm, 4 mm, 4.5 mm or 5 mm.

[0176] In this embodiment, the fillet radius between the guide bevel 1213 and the end face of the first support rib 121 is set to 2.5mm-5mm, so that the fillet between the guide bevel 1213 and the end face of the first support rib 121 is not too large, which is beneficial to the production of the fillet and reduces the impact on the guide bevel 1213; at the same time, it also ensures that the fillet between the guide bevel 1213 and the end face of the first support rib 121 is not too small, which is beneficial to the reduction of vortexes, thereby increasing the flow rate and smoothness of the airflow and improving the exhaust effect.

[0177] According to some embodiments of the present invention, Fig. 9As shown, the side surface of the first support segment 1211 facing the airflow channel 13 also includes a drainage slope 1214, and the drainage slope 1214 is connected to one end of the guide slope 1213 facing the second support segment 1212. In the direction from the first support segment 1211 toward the second support segment 1212, the drainage slope 1214 extends obliquely toward the other side surface of the first support rib 121 away from the airflow channel 13, and the confluence area 132 is formed between the drainage slopes 1214 of the two first support ribs 121.

[0178] It can be understood that the inclination direction of the drainage slope 1214 is opposite to the inclination direction of the guide slope 1213, and thus, the guide slope 1213 of the same first support section 1211 can hinder the movement of the airflow entering from the end away from the guide slope 1213 in the length direction. Therefore, when the airflow moves from the two guide sections 131 to the confluence area 132, when the airflow moves to the drainage slope 1214, the drainage slope 1214 will hinder the flow of the airflow, and thus the original flow trajectory of the airflow can be changed, so that the airflow moves along the tangent direction of the drainage slope 1214. At the same time, since the two first support ribs 121 are rotationally symmetrically arranged along the center of the support plate 11, the two airflows entering the confluence area 132 have opposite movement directions, and the two airflows do not directly collide, which can further promote the generation of vortices and accelerate the discharge of gas.

[0179] By providing the guide slope 1214, this embodiment can change the original flow trajectory of the airflow, so that the two airflows entering the confluence area 132 move in opposite directions and do not directly collide with each other, thereby further promoting the generation of vortices and accelerating the discharge of gas.

[0180] According to some embodiments of the present invention, Fig. 9 As shown, the angle between the drainage slope 1214 and the length direction of the support plate 11 is greater than the angle between the guide slope 1213 and the length direction of the support plate 11 .

[0181] Among them, the angle between the drainage slope 1214 and the length direction of the support plate 11 refers to the angle between the tangent of the drainage slope 1214 and the edge of the length direction of the support plate 11; the angle between the guide slope 1213 and the length direction of the support plate 11 refers to the angle between the tangent of the guide slope 1213 and the edge of the length direction of the support plate 11.

[0182] Specifically, the length dimension of the drainage slope 1214 in the length direction of the support plate 11 can be controlled by controlling the size of the angle between the drainage slope 1214 and the length direction of the support plate 11, and the length dimension of the guide slope 1213 in the length direction of the support plate 11 can be controlled by controlling the size of the angle between the guide slope 1213 and the length direction of the support plate 11, thereby limiting the size of the guide section 131 and the confluence area 132.

[0183] In this embodiment, by setting the angle between the drainage slope 1214 and the length direction of the support plate 11 to be greater than the angle between the guide slope 1213 and the length direction of the support plate 11, the range of the confluence area 132 can be limited to be smaller than the range of the guide section 131, and the range of the confluence area 132 can be limited to the position of the explosion-proof valve, thereby increasing the exhaust effect.

[0184] According to some embodiments of the present invention, Fig. 9 As shown, the drainage slope 1214 is connected to the guide slope 1213 in an arc.

[0185] By setting an arc connection between the drainage slope 1214 and the guide slope 1213, this embodiment can reduce the generation of vortices at the connection between the drainage slope 1214 and the guide slope 1213, thereby increasing the speed of air flow and further accelerating the generation of vortices, so that the air flow can be quickly discharged from the interior of the battery cell 100, reducing the pressure inside the battery cell 100 and reducing the occurrence of thermal runaway of the battery cell 100.

[0186] According to some embodiments of the present invention, a surface of one side of the second supporting segment 1212 facing the airflow channel 13 is a plane parallel to the length direction of the supporting plate 11 .

[0187] Specifically, the cross section of the second support segment 1212 is formed into a rectangle, one side surface of the second support segment 1212 in the length direction is flush with the edge of the support plate 11 in the length direction, and the other side is parallel to the plane of the support plate 11 in the length direction.

[0188] In this embodiment, the side surface of the second support section 1212 facing the airflow channel 13 is set to be a plane parallel to the length direction of the support plate 11. In this way, the production convenience of the support frame 12 can be improved, the production rate of the support frame 12 can be increased, and at the same time, it is also convenient to control the size of the airflow channel 13 to ensure the exhaust effect.

[0189] According to some embodiments of the present invention, in the width direction of the support plate 11 , the ratio of the width of the second support segment 1212 to the maximum width of the first support segment 1211 is 0.25-0.45.

[0190] For example, in the width direction of the support plate 11 , the ratio of the width of the second support segment 1212 to the maximum width of the first support segment 1211 may be 0.25, 0.3, 0.4 or 0.45.

[0191] In this embodiment, by setting the ratio of the width of the second support section 1212 to the maximum width of the first support section 1211 to 0.25-0.45, the width of the second support section 1212 can be made not too large, so as to ensure the width of the airflow channel 13 and meet the exhaust requirements of the battery cell 100; at the same time, the width of the second support section 1212 can be made not too small, which is beneficial to improving the supporting effect of the support plate 11, thereby improving the supporting strength of the bottom bracket 10 and effectively reducing the risk of the bottom bracket 10 being crushed.

[0192] According to some embodiments of the present invention, the ratio of the projection area of ​​the support frame 12 within the first surface to the area of ​​the first surface is 0.15-0.4.

[0193] For example, the ratio of the projected area of ​​the support frame 12 within the first surface to the area of ​​the first surface may be 0.15, 0.2, 0.25, 0.3, 0.35 or 0.4.

[0194] In this embodiment, the ratio of the projected area of ​​the support frame 12 within the first surface to the area of ​​the first surface is set to 0.15-0.4, which is beneficial to improving the structural strength of the bottom bracket 10 and improving its structural stability, thereby effectively preventing the bottom bracket from being crushed; at the same time, the flow area of ​​the airflow channel 13 can be limited, so that the flow area of ​​the airflow channel 13 can meet the exhaust demand, so that the gas in the battery cell 100 cycle process can be discharged in time, reducing the internal pressure of the battery cell 100, thereby reducing the probability of thermal runaway of the battery cell 100, and improving the reliability and service life of the battery cell 100.

[0195] According to some embodiments of the present invention, in the thickness direction of the support plate 11 , the height of the support frame 12 is 0.6 mm-5 mm.

[0196] For example, in the thickness direction of the support plate 11, the height of the support frame 12 can be 0.6mm, 0.7mm, 0.8mm, 0.9mm, 1mm, 2mm, 3mm, 4mm or 5mm. The gas content generated by different types of battery cells 100 is different, and the height of the support frame 12 can be selected according to the gas production, so that the bottom bracket 10 can not only ensure the smooth exhaust of the battery cell 100, but also reduce the occupied space of the bottom bracket 10, thereby improving the energy density of the battery cell 100.

[0197] In this embodiment, the height of the support frame 12 is set to 0.6mm-5mm in the thickness direction of the support plate 11, so that the bottom bracket 10 can not only ensure the smooth exhaust of the battery cell 100, but also reduce the occupied space of the bottom bracket 10, thereby improving the energy density of the battery cell 100.

[0198] According to some embodiments of the present invention, in the thickness direction of the support plate 11 , the height of the support frame 12 is 0.6 mm-3 mm.

[0199] For example, in the thickness direction of the support plate 11 , the height of the support frame 12 may be 0.6 mm, 0.7 mm, 0.8 mm, 0.9 mm, 1 mm, 2 mm or 3 mm.

[0200] In this embodiment, by setting the height of the support frame 12 to 0.6mm-3mm in the thickness direction of the support plate 11, the height of the support frame 12 can be made not too high, which is beneficial to improving the energy density of the battery cell 100. At the same time, the height of the support frame 12 can be made not too small, so that the height of the support frame 12 can meet the exhaust requirements, thereby improving the exhaust effect.

[0201] According to some embodiments of the present invention, the battery cell 100 is a lithium iron phosphate battery 1000, and the height of the support frame 12 is 0.6 mm-1 mm; or, the battery cell 100 is a ternary polymer lithium battery 1000, and the height of the support frame 12 is 0.6 mm-3 mm.

[0202] Among them, in some specific embodiments, the battery cell 100 is a lithium iron phosphate battery 1000, and the height of the support frame 12 is 0.6mm-1mm, for example, the height of the support frame 12 can be 0.6mm, 0.7mm, 0.8mm, 0.9mm or 1mm; in other specific embodiments, the battery cell 100 is a ternary polymer lithium battery 1000, and the height of the support frame 12 is 0.6mm-3mm, for example, the height of the support frame 12 can be 0.6mm, 0.7mm, 0.8mm, 0.9mm, 1mm, 2mm or 3mm.

[0203] Specifically, the lithium iron phosphate battery 1000 refers to a lithium ion battery 1000 using lithium iron phosphate as the positive electrode material; the ternary polymer lithium battery 1000 refers to a lithium battery 1000 using nickel cobalt manganese oxide as the positive electrode material and graphite as the negative electrode material. Among them, since there are more surface free lithium compounds on the surface of the ternary material, the gas production of the ternary polymer lithium battery 1000 during the cycle is greater than that of the lithium iron phosphate battery 1000.

[0204] In this embodiment, when the battery cell 100 is a lithium iron phosphate battery 1000, the height of the support frame 12 is set to 0.6mm-1mm, and when the battery cell 100 is a ternary polymer lithium battery 1000, the height of the support frame 12 is set to 0.6mm-3mm. The height of the support frame 12 can be designed according to the type of the battery cell 100, so that the bottom bracket 10 can meet the exhaust requirements while reducing the occupied space of the bottom bracket 10 and improving the energy density of the battery cell 100.

[0205] According to some embodiments of the present invention, the thickness of the support plate 11 is 0.4 mm-0.6 mm.

[0206] For example, the thickness of the support plate 11 may be 0.4 mm, 0.5 mm or 0.6 mm.

[0207] In this embodiment, by setting the thickness of the support plate 11 to 0.4mm-0.6mm, the support plate 11 can satisfy the supporting function of the bottom bracket 10 on the electrode assembly 30 while reducing the material used for the support plate 11, thereby reducing the production difficulty and production cost of the support plate 11; at the same time, setting the thickness range of the support plate 11 to [0.4mm, 0.6mm] can also reduce the thickness of the bottom bracket 10, thereby improving the energy density of the battery cell 100.

[0208] According to some embodiments of the present invention, the bottom bracket 10 is a polypropylene member, or the bottom bracket 10 is an aluminum member.

[0209] In some specific embodiments, the bottom bracket 10 is a polypropylene member; in other specific embodiments, the bottom bracket 10 is an aluminum member.

[0210] Specifically, polypropylene is referred to as PP, which is a polymer formed by polyaddition reaction of propylene. Polypropylene is a thermoplastic synthetic resin with excellent performance, and has good corrosion resistance, heat resistance, electrical insulation, high-strength mechanical properties and high wear resistance processing performance. Therefore, the use of polypropylene material to make the bottom bracket 10 can reduce the possibility of the bottom bracket 10 being corroded or crushed by the electrolyte, thereby improving the reliability and service life of the bottom bracket 10. In addition, the price of polypropylene material is relatively low, and the use of polypropylene material can also reduce the production cost of the bottom bracket 10 and the production cost of the battery cell 100.

[0211] Aluminum is a product made of aluminum and other alloy elements, and has good structural strength, corrosion resistance, heat resistance and electrical insulation, and aluminum is light in weight. Therefore, the bottom bracket 10 is made of aluminum, which can meet the supporting performance and corrosion resistance of the bottom bracket 10 while reducing the weight of the bottom bracket 10, thereby reducing the weight of the battery cell 100, thereby achieving lightweight battery 1000.

[0212] In this embodiment, by setting the bottom bracket 10 to be a polypropylene part, the possibility of the bottom bracket 10 being corroded or crushed by the electrolyte can be reduced, thereby improving the reliability and service life of the bottom bracket 10; at the same time, the production cost of the battery cell 100 can be reduced; by setting the bottom bracket 10 to be an aluminum part, the supporting performance and corrosion resistance of the bottom bracket 10 can be increased while the weight of the bottom bracket 10 can be reduced, thereby reducing the weight of the battery cell 100, thereby achieving lightweight battery 1000.

[0213] The battery 1000 according to the second embodiment of the present invention includes the battery cell 100 according to the first embodiment of the present invention.

[0214] In some specific embodiments of the present invention, for example Figure 3 As shown, the battery 1000 may further include: a main box 201 and a cover plate 202 , the main box 201 having a cavity with an open top, a plurality of battery cells 100 being disposed in the cavity, and the cover plate 202 being sealed on the top of the main box 201 by fasteners.

[0215] Optionally, a plurality of battery cells 100 may be stacked and arranged in the cavity along a thickness direction of the battery cells 100 .

[0216] Optionally, the main box 201 is formed in the shape of a rectangular box body, the inner side of the main box 201 defines a cavity, the top of the cavity is open, the main box 201 is provided with a plurality of first fixing holes, the cover plate 202 is formed in the shape of a horizontally arranged flat plate, the cover plate 202 is provided with a plurality of second fixing holes that penetrate the cover plate 202 in the up and down directions, the plurality of first fixing holes correspond to the plurality of second fixing holes one by one and are opposite to each other up and down, the battery 1000 also includes a plurality of fasteners, the plurality of fasteners pass through the first fixing holes and the second fixing holes to fasten the cover plate 202 to the upper side of the main box 201 body 200.

[0217] Optionally, the cover plate 202 may be a carbon steel plate, an aluminum plate or a composite material plate.

[0218] This embodiment can facilitate the loading of the battery cell 100 into the box body 200 by configuring the box body 200 as a main box 201 and a cover plate 202 arranged separately. The main box 201 and the cover plate 202 are connected by fasteners to achieve a detachable connection, which is convenient for maintenance and replacement, and can ensure the connection strength between the main box 201 and the cover plate 202, thereby ensuring the overall structural strength of the battery 1000.

[0219] In some specific embodiments of the present invention, a first adhesive layer is provided on the bottom wall of the cavity, and the bottoms of the multiple battery cells 100 are connected to the bottom wall of the main box 201 through the first adhesive layer; and / or, a second adhesive layer is provided on the cover plate 202, and the tops of the multiple battery cells 100 are connected to the cover plate 202 through the second adhesive layer.

[0220] The battery 1000 may include only the first glue layer, or only the second glue layer, or may include both the first glue layer and the second glue layer. The first glue layer is used to bond and connect the bottom wall of the main box 201 and the battery cell 100, and the second glue layer is used to bond and connect the cover plate 202 and the battery cell 100, so as to reliably fix multiple battery cells 100 in the box 200, improve the reliability and stability of the connection between the battery cell 100 and the box 200, and prevent the battery cell 100 from shaking in the box 200.

[0221] In this embodiment, a first adhesive layer and a second adhesive layer are provided, and the bottom of the battery cell 100 is bonded and fixed to the bottom wall of the main box 201 through the first adhesive layer, and the top of the battery cell 100 is bonded and fixed to the cover plate 202 through the second adhesive layer. In this way, the overall strength of the battery 1000 can be improved and the connection stability of the battery cell 100 can be ensured.

[0222] The battery 1000 according to the embodiment of the present invention is provided with the battery cell 100 of the embodiment of the first aspect, thereby improving the overall performance of the battery 1000.

[0223] The electric device according to the embodiment of the third aspect of the present invention comprises the battery 1000 according to the embodiment of the second aspect of the present invention.

[0224] According to the electric device of the embodiment of the present invention, the overall performance of the electric device is improved by providing the battery 1000 of the embodiment of the third aspect.

[0225] The following will refer to Figure 4-Figure 12 A battery cell 100 according to two specific embodiments of the present invention is described.

[0226] Embodiment 1,

[0227] Reference Figure 4 The battery cell 100 includes an end cap 40, a transfer sheet 50, an electrode assembly 30, a bottom bracket 10 and a shell 20, wherein the shell 20 is formed with an open end, and the end cap 40 is arranged on one side of the opening of the shell 20 to seal the open end of the shell 20; the shell 20 has a accommodating cavity 21, and an explosion-proof valve is provided at the bottom of the shell 20; the electrode assembly 30 and the bottom bracket 10 are both arranged in the accommodating cavity 21, the bottom bracket 10 is arranged on the bottom wall of the accommodating cavity 21, the electrode assembly 30 is arranged on the upper side of the bottom bracket 10, and the bottom bracket 10 and the bottom wall of the shell 20 jointly define an exhaust space; the bottom bracket 10 is a polypropylene part.

[0228] Specifically, the bottom bracket 10 further includes a support plate 11 and a support frame 12 , wherein the support plate 11 is formed as a rectangular plate, and the support frame 12 is disposed at the lower side of the support plate 11 .

[0229] The support frame 12 includes two first support ribs 121 and two second support ribs 122, wherein the first support rib 121 and the second support rib 122 both extend along the length direction of the support plate 11, the two first support ribs 121 are respectively arranged at the two ends of the support plate 11 in the width direction, and the two first support ribs 121 are respectively flush with the two side edges of the support plate 11 in the width direction; the two second support ribs 122 are respectively arranged at the two ends of the support plate 11 in the length direction, and are arranged between the two first support ribs 121, and in the length direction of the support plate 11, one end of the second support rib 122 is flush with the end edge of the support plate 11 in the length direction, and the other end extends toward the middle of the support plate 11 and is formed as an arc surface convex in the direction away from the end edge of the support plate 11; an air flow channel 13 is defined between the two first support ribs 121.

[0230] Furthermore, in the direction from one end toward the other end in the length direction of the support plate 11, one side edge of the first support rib 121 toward the airflow channel 13 extends along an arc line protruding toward the airflow channel 13, and the diameter of the arc line is 130mm-180mm.

[0231] In the width direction of the support plate 11, the width of the first support rib 121 at both ends in the length direction of the support plate 11 is 8mm-11mm; the maximum width of the first support rib 121 is 12mm-16mm. In the length direction of the support plate 11, the length of the second support rib 122 is 20mm-30mm; the ratio of the length of the second support rib 122 to the length of the support plate 11 is 0.07-0.12. In the thickness direction of the support plate 11, the thickness of the support plate 11 is 0.4mm-0.6mm, and the height of the support frame 12 is 0.6mm-3mm.

[0232] When the battery cell 100 is recycled, a large amount of gas is generated inside the battery cell 100. The gas can enter the air flow channel 13 through the two ends of the first support rib 121 in the length direction, and then be drained to the explosion-proof valve through the air flow channel 13 for discharge. Therefore, the bottom bracket 10 of the present application can improve the exhaust condition inside the battery cell 100, reduce the internal pressure of the battery cell 100, and further reduce the probability of thermal runaway of the battery cell 100 and the risk of cracking of the weld of the shell 20 caused by excessive pressure.

[0233] According to the battery cell 100 of the embodiment of the present invention, by setting the bottom bracket 10 of the first embodiment, the air flow channel 13 is defined by two first support ribs 121, and the two first support ribs 121 are set to be flush with the two side edges of the support plate 11 in the width direction, which can effectively prevent the formation of a flow stagnation zone at the edge of the first support rib 121 and the support plate 11, reduce the bulging phenomenon caused by the gathering of airflow at the connection between the first support rib 121 and the support plate 11, and enable the airflow to enter the airflow channel 13 from both ends of the airflow channel 13, thereby improving the exhaust effect; at the same time, the cross-sectional area of ​​the airflow channel 13 can be increased, and the exhaust space of the bottom bracket 10 can be further increased to improve the exhaust effect, thereby reducing the internal pressure of the battery cell 100, reducing the probability of thermal runaway of the battery cell 100 and the risk of cracking of the weld of the shell 20 caused by excessive pressure.

[0234] Embodiment 2:

[0235] Reference Fig. 9 The structure of this embodiment is substantially the same as that of the first embodiment, wherein the same components are marked with the same reference numerals, and the only difference is that the support frame 12 described in the first embodiment includes two first support ribs 121 and two second support ribs 122, and the first support rib 121 extends along an arc line toward one side edge of the air flow channel 13, while the support frame 12 described in the second embodiment only includes two first support ribs 121, and the first support rib 121 includes a first support segment 1211 and a second support segment 1212.

[0236] Specifically, the first support section 1211 and the second support section 1212 are connected in sequence in the length direction of the support plate 11, wherein a portion of the side surface of the first support section 1211 facing the airflow channel 13 is formed as a guide slope 1213, and in the direction from the first support section 1211 to the second support section 1212, the guide slope 1213 extends obliquely toward another first support rib 121; the other portion is formed as a drainage slope 1214, and the drainage slope 1214 is connected to the guide slope 1213 facing the second support section At one end of 1212, in the direction from the first support section 1211 toward the second support section 1212, the drainage slope 1214 extends obliquely toward the other side surface of the first support rib 121 that is away from the air flow channel 13, and the drainage slope 1214 is connected to the guide slope 1213 in an arc shape, one end of the second support section 1212 is connected to the drainage slope 1214, and the other end extends along the length direction of the support plate 11, and the side surface of the second support section 1212 facing the air flow channel 13 is a plane parallel to the length direction of the support plate 11.

[0237] Furthermore, the airflow channel 13 includes a guide section 131 and a confluence area 132. There are two guide sections 131, which are respectively connected to both sides of the confluence area 132 in the length direction of the support plate 11. The confluence area 132 is formed between the drainage slopes 1214 of the two first support ribs 121.

[0238] In addition, the guide slope 1213 and the end surface of the first support rib 121 are rounded, and the rounded radius is 2.5mm-5mm. In the width direction of the support plate 11, the ratio of the width of the second support segment 1212 to the maximum width of the first support segment 1211 is 0.25-0.45.

[0239] According to the battery cell 100 of the embodiment of the present invention, by providing the bottom bracket 10 of the present embodiment, the exhaust effect can be improved while the number of supporting ribs can be reduced, thereby simplifying the production process of the bottom bracket 10, reducing the production cost of the bottom bracket 10, and improving the production rate of the bottom bracket 10, thereby reducing the overall cost of the battery cell 100 and improving the assembly rate of the battery cell 100.

[0240] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit them; although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or replace some or all of the technical features therein by equivalents; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the scope of the technical solutions of the embodiments of the present invention, and they should all be included in the scope of the claims and specification of the present invention. In particular, as long as there is no structural conflict, the various technical features mentioned in each embodiment can be combined in any way. The present invention is not limited to the specific embodiments disclosed herein, but includes all technical solutions that fall within the scope of the claims.

Claims

1. A battery cell, characterized in that: include: A housing (20), wherein the housing (20) defines a receiving chamber (21), and an explosion-proof valve is provided at the bottom of the housing (20); A bottom bracket (10), the bottom bracket (10) being arranged on the bottom wall of the accommodating cavity (21), the bottom bracket (10) comprising: A support plate (11), wherein a side surface of the support plate (11) facing the bottom wall of the accommodating cavity (21) is a first surface; A support frame (12), the support frame (12) comprising at least one first support rib (121), the first support rib (121) being provided on the first surface and extending along the length direction of the support plate (11), at least one first support rib (121) being arranged on at least one side edge of the support plate (11) in the width direction, and an air flow channel (13) communicating with the explosion-proof valve is defined between the first support rib (121), the first surface and the bottom wall of the accommodating cavity (21); An electrode assembly (30), the electrode assembly (30) being arranged in the accommodating cavity (21) and supported on the second surface of the support plate (11), the first surface and the second surface being arranged opposite to each other in the thickness direction of the support plate (11).

2. The battery cell according to claim 1, characterized in that: The number of the first supporting ribs (121) is two, and the two first supporting ribs (121) are respectively arranged on the two side edges of the supporting plate (11) in the width direction. At least parts of the two first support ribs (121) are respectively flush with the two side edges of the support plate (11) in the width direction.

3. The battery cell according to claim 1, characterized in that: The first support rib (121) extends from one end to the other end of the support plate (11) in the length direction, and the width of the first support rib (121) in the width direction of the support plate (11) gradually increases in the direction from the two ends in the length direction of the support plate (11) toward the middle.

4. The battery cell according to claim 3, in a direction from one end toward the other end in the length direction of the support plate (11), a side edge of the first support rib (121) facing the air flow channel (13) extends along an arc line protruding toward the air flow channel (13).

5. The battery cell according to claim 4, characterized in that: The one side edge of the first supporting rib (121) extends along an arc line, and the diameter of the arc line is 130 mm-180 mm.

6. The battery cell according to claim 3, characterized in that: In the width direction of the support plate (11), the width of the first support rib (121) at both ends in the length direction of the support plate (11) is 8 mm-11 mm.

7. The battery cell according to claim 3, characterized in that: In the width direction of the support plate (11), the maximum width of the first support rib (121) is 12 mm-16 mm.

8. The battery cell according to any one of claims 1 to 7, characterized in that: The support frame (12) further comprises two second support ribs (122), the second support ribs (122) extending along the length direction of the support plate (11) and arranged between the two first support ribs (121), and the two second support ribs (122) are respectively arranged at two ends of the support plate (11) in the length direction.

9. The battery cell according to claim 8, characterized in that: In the length direction of the support plate (11), one end of the second support rib (122) is flush with the end edge of the support plate (11) in the length direction.

10. The battery cell according to claim 9, characterized in that: In the length direction of the support plate (11), the length of the second support rib (122) is 20 mm-30 mm.

11. The battery cell according to claim 9, characterized in that: In the length direction of the support plate (11), the ratio of the length of the second support rib (122) to the length of the support plate (11) is 0.07-0.

12.

12. The battery cell according to claim 9, characterized in that: The end surface of the other end of the second supporting rib (122) is a curved surface that bulges in a direction away from the end edge of the supporting plate (11).

13. The battery cell according to claim 1, characterized in that: The airflow channel (13) comprises a guide section (131) and a confluence area (132); the number of the guide sections (131) is two and they are respectively connected to two sides of the confluence area (132) in the length direction of the support plate (11); at least one side wall of the guide section (131) in the width direction of the support plate (11) is formed with a guide slope (1213); in the direction from the guide section (131) toward the confluence area (132), the guide slopes (1213) of the two guide sections (131) extend obliquely toward two sides of the confluence area (132) in the width direction of the support plate (11).

14. The battery cell according to claim 13, characterized in that: The two first supporting ribs (121) are arranged rotationally symmetrically about the center of the supporting plate (11) in the first surface.

15. The battery cell according to claim 14, characterized in that: The first supporting rib (121) comprises: a first supporting section (1211) and a second supporting section (1212) which are connected in sequence in the length direction of the supporting plate (11); at least a portion of a side surface of the first supporting section (1211) facing the airflow channel (13) is formed as the guiding slope (1213); in the direction from the first supporting section (1211) toward the second supporting section (1212), the guiding slope (1213) extends obliquely toward another first supporting rib (121).

16. The battery cell according to claim 15, characterized in that: The corner between the guiding inclined surface (1213) and the end surface of the first supporting rib (121) is rounded.

17. The battery cell according to claim 16, characterized in that: The fillet radius between the guiding inclined surface (1213) and the end surface of the first supporting rib (121) is 2.5 mm-5 mm.

18. The battery cell according to claim 15, characterized in that: The surface of one side of the first support section (1211) facing the airflow channel (13) also includes a drainage slope (1214), and the drainage slope (1214) is connected to one end of the guide slope (1213) facing the second support section (1212). In the direction from the first support section (1211) toward the second support section (1212), the drainage slope (1214) extends obliquely toward the other side surface of the first support rib (121) away from the airflow channel (13), and the confluence area (132) is formed between the drainage slopes (1214) of the two first support ribs (121).

19. The battery cell according to claim 18, characterized in that: The angle between the drainage slope (1214) and the length direction of the support plate (11) is greater than the angle between the guide slope (1213) and the length direction of the support plate (11).

20. The battery cell according to claim 18, characterized in that: The drainage slope (1214) is connected to the guide slope (1213) in an arc.

21. The battery cell according to claim 15, characterized in that: A side surface of the second supporting section (1212) facing the airflow channel (13) is a plane parallel to the length direction of the supporting plate (11).

22. The battery cell according to claim 21, characterized in that: In the width direction of the support plate (11), the ratio of the width of the second support segment (1212) to the maximum width of the first support segment (1211) is 0.25-0.

45.

23. The battery cell according to claim 1, characterized in that: The ratio of the projection area of ​​the support frame (12) within the first surface to the area of ​​the first surface is 0.15-0.

4.

24. The battery cell according to claim 1, characterized in that In the thickness direction of the support plate (11), the height of the support frame (12) is 0.6 mm-5 mm.

25. The battery cell according to claim 1, characterized in that In the thickness direction of the support plate (11), the height of the support frame (12) is 0.6 mm-3 mm.

26. The battery cell according to claim 25, characterized in that: The battery cell is a lithium iron phosphate battery, and the height of the support frame (12) is 0.6 mm-1 mm; or, The battery monomer is a ternary polymer lithium battery, and the height of the support frame (12) is 0.6 mm-3 mm.

27. The battery cell according to claim 1, characterized in that: The thickness of the support plate (11) is 0.4 mm-0.6 mm.

28. The battery cell according to claim 1, characterized in that: The bottom bracket (10) is a polypropylene part, or the bottom bracket (10) is an aluminum part.

29. A battery, characterized in that: Comprising the battery cell according to claims 1-28.

30. An electrical equipment, characterized in that: Comprising a battery according to claim 29.

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