CN218385441U - Battery cell shell, battery cell, battery and electric device - Google Patents

Abstract

The application discloses free casing of battery, battery monomer, battery and power consumption device. The single battery shell comprises a bottom wall and at least one side wall, the side wall and the bottom wall enclose a containing cavity for containing the single battery electrode assembly, and the thickness of the bottom wall is larger than that of the side wall. This application has increased the support intensity of diapire, has improved the bulk strength of casing, has improved the stability and the security of battery. And the thickness of the side wall is thinner, so that the volume of the battery module can be reduced and the volume energy density of the whole battery can be increased after the plurality of battery monomers are arranged side by side.

Description

Battery cell shell, battery cell, battery and electric device

Technical Field

The application relates to the technical field of batteries, in particular to a single battery shell, a single battery, a battery and an electric device.

Background

The battery cell is widely used in electronic devices such as a mobile phone, a notebook computer, a battery car, an electric airplane, an electric ship, an electric toy car, an electric toy ship, an electric toy airplane, an electric tool, and the like. The battery monomer can comprise a cadmium-nickel battery monomer, a hydrogen-nickel battery monomer, a lithium ion battery monomer, a secondary alkaline zinc-manganese battery monomer and the like.

In the development of battery technology, how to improve stability and safety is a research direction in battery technology.

SUMMERY OF THE UTILITY MODEL

The embodiment of the application provides a single battery shell, a single battery, a battery and an electric device, and the stability and the safety of the battery can be improved.

In a first aspect, an embodiment of the present application provides a single battery case, where the case includes a bottom wall and at least one side wall, the side wall and the bottom wall enclose a receiving cavity for receiving an electrode assembly of the single battery, and a thickness of the bottom wall is greater than a thickness of the side wall.

Among the above-mentioned scheme, set up the diapire of the free casing of battery for being greater than the thickness of lateral wall, the support intensity of multiplicable diapire improves the bulk strength of casing, improves the stability and the security of battery. And the thickness of the side wall is thinner, and after a plurality of battery monomers are arranged side by side, the volume of the battery module can be reduced, and the volume energy density of the whole battery is increased.

In some embodiments, the housing further comprises a connecting wall for connecting the bottom wall and the side wall; at least a portion of the connecting wall is arcuate.

In the above-mentioned scheme, the connecting wall that will connect diapire and lateral wall sets up to the arc, and the crackle of reducible connecting wall prevents the connecting wall fracture, increases the intensity of the free casing of battery.

In some embodiments, the connecting wall includes a first wall surface and a second wall surface, the first wall surface is disposed close to the accommodating cavity, the second wall surface is disposed opposite to the first wall surface and is located on a side of the first wall surface away from the accommodating cavity, and the first wall surface and the second wall surface are respectively in an arc shape protruding away from the accommodating cavity.

In the above scheme, the connecting wall has the first wall and the second wall that set up relatively, and first wall orientation holds the chamber setting, and the chamber setting is kept away from holding to the second wall, and first wall and second wall are to keeping away from the direction protrusion that holds the chamber, avoid occupying the inside volume of casing, provide more accommodation space for electrode subassembly.

In some embodiments, the connecting wall satisfies the following equation: and T is more than or equal to R2-R1 is more than or equal to U, wherein T is the thickness of the side wall, U is the thickness of the bottom wall, and R1 and R2 are the bending radii of the first wall surface and the second wall surface respectively.

In the above scheme, the bending radius difference value of the second wall surface and the first wall surface is greater than or equal to the side wall thickness and less than or equal to the bottom wall thickness, so that the thickness of the connecting wall is within a proper range, the thickness of the connecting wall is ensured to be larger, the connecting wall is prevented from cracking and breaking, the thickness of the connecting wall is prevented from being too large, the difficulty in realizing the process is avoided, or the installation difficulty of the electrode assembly is increased.

In some embodiments, the first wall has a bend radius of 0.5mm to 1.5mm.

In the above scheme, the bending radius of the first wall surface is in a proper range, so that the process stretching of the shell material is facilitated, the bending radius of the first wall surface can be prevented from being too large, and the volume energy density of the battery monomer is ensured to be large.

In some embodiments, the housing has a vickers hardness of less than 95.

In the scheme, the Vickers hardness of the shell is low, the ductility of the shell material is high, and the shell is convenient to stretch in the process of manufacturing the shell.

In some embodiments, the bottom wall includes a first inner surface and a first outer surface that are oppositely disposed, the first inner surface being disposed proximate to the receiving cavity; the side wall comprises a second inner surface and a second outer surface which are oppositely arranged, and the second inner surface is arranged close to the accommodating cavity; the first wall surface is tangent to the first inner surface and the second inner surface respectively, and the second wall surface is arranged in a protruding mode relative to the first wall surface in the direction away from the containing cavity.

In the above aspect, the first inner surface and the second inner surface are connected by a first wall surface, and the first outer surface and the second outer surface are connected by a second wall surface. First wall is the natural transition circular arc tangent with first internal surface and second internal surface respectively, and the relative virtual circular arc of second wall sets up to the direction protrusion of keeping away from first wall, and this virtual circular arc is respectively with the tangent virtual face of first surface and second surface, has both increased the thickness of connecting the wall, can guarantee again that the inside volume that holds the chamber of casing is great, does not influence the free volume energy density of battery.

In some embodiments, the second wall surface has a dimension in a direction perpendicular to the bottom wall of 1 to 5mm.

Among the above-mentioned scheme, the size range of second wall along the direction of perpendicular to diapire is suitable, can avoid forming sharp closed angle between second wall and the lateral wall, prevents to measure too big moreover, and the second wall is at the tensile in-process of the technology preparation of casing, and the connection wall thins gradually, and the minimum wall thickness that appears the connection wall is less than the phenomenon of lateral wall thickness, has guaranteed the intensity of connection wall.

In some embodiments, the minimum wall thickness of the connecting wall is greater than or equal to the thickness of the side wall.

In the above scheme, the thickness of the connecting wall is further ensured, and the overall strength of the shell is improved.

In some embodiments, the vickers hardness of the shell is 95-200, and the vickers hardness of the shell is higher, so that the overall strength of the shell is improved.

In some embodiments, the bottom wall includes a first inner surface and a first outer surface disposed opposite, the first inner surface disposed proximate to the receiving cavity; the side wall comprises a second inner surface and a second outer surface which are oppositely arranged, and the second inner surface is arranged close to the accommodating cavity; the first wall is tangent to the first inner surface and the second inner surface, and the second wall is tangent to the first outer surface and the second outer surface.

In the above aspect, the first inner surface and the second inner surface are connected by a first wall surface, and the first outer surface and the second outer surface are connected by a second wall surface. Because the Vickers hardness of the shell is higher, the first wall surface is respectively tangent to the first inner surface and the second inner surface, the second wall surface is respectively tangent to the first outer surface and the second outer surface, and the first wall surface and the second wall surface are both natural transition arcs, namely, the connecting wall does not need thickening treatment, thereby being convenient for process preparation.

In some embodiments, the second wall has a bend radius of 1 to 2mm. The connecting wall is designed to be a round angle, thickening treatment is not needed, and therefore the second wall surface does not need to be arranged in a protruding mode towards the direction deviating from the first wall surface. The bending radius of the second wall surface is in a proper range, so that the shell material can be conveniently stretched in the process of manufacturing, and the phenomenon that sharp corners occur between the second wall surface and the side wall due to the fact that the bending radius of the second wall surface is too large can be avoided.

In a second aspect, the present application provides a battery cell, which includes an electrode assembly and the case of any of the above embodiments, wherein the electrode assembly is accommodated in the accommodating cavity.

In a third aspect, an embodiment of the present application provides a battery, including the above battery cell.

In a fourth aspect, an embodiment of the present application provides an electric device, which includes the above battery, where the battery is used to provide electric energy.

The foregoing description is only an overview of the technical solutions of the present application, and the present application can be implemented according to the content of the description in order to make the technical means of the present application more clearly understood, and the following detailed description of the present application is given in order to make the above and other objects, features, and advantages of the present application more clearly understandable.

Drawings

In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings needed to be used in the embodiments of the present application will be briefly described below, and it is obvious that the drawings described below are only some embodiments of the present application, and it is obvious for those skilled in the art to obtain other drawings based on these drawings without creative efforts.

FIG. 1 is a schematic illustration of a vehicle according to some embodiments of the present application;

FIG. 2 is a schematic diagram of a battery according to some embodiments of the present application;

fig. 3 is a schematic structural view of the battery module shown in fig. 2;

FIG. 4 is an exploded view of a battery cell according to some embodiments of the present disclosure;

FIG. 5 is a schematic structural view of a housing according to some embodiments of the present application;

FIG. 6 is a schematic view of another angle of the housing of FIG. 5;

FIG. 7 is an enlarged view of portion A of FIG. 6;

FIG. 8 is a schematic view of a housing according to still other embodiments of the present application;

FIG. 9 is a schematic view of the housing of FIG. 8 at another angle;

fig. 10 is an enlarged view of a portion a of fig. 9.

The reference numbers are as follows:

a vehicle 1000; a battery 100; a controller 200; a motor 300; a case 10; an upper cover 10a; a lower cover 10b; a battery module 400; a battery cell 20; a housing 22; an end cap 21; an electrode terminal 26; an electrode assembly 23; the accommodation chamber 22a; a bottom wall 30; a side wall 40; a connecting wall 50; a first wall surface 51; a second wall 52; a first inner surface 31, a first outer surface 32; a second inner surface 41; a second outer surface 42.

Detailed Description

Embodiments of the present application will be described in further detail below with reference to the drawings and examples. The following detailed description of the embodiments and the accompanying drawings are provided to illustrate the principles of the application and are not intended to limit the scope of the application, i.e., the application is not limited to the described embodiments.

In the description of the present application, it is to be noted that, unless otherwise specified, "a plurality" means two or more; the terms "upper," "lower," "left," "right," "inner," "outer," and the like, indicate an orientation or positional relationship that is merely for convenience in describing the application and to simplify the description, and do not indicate or imply that the referenced devices or elements must be in a particular orientation, constructed and operated in a particular orientation, and therefore should not be construed as limiting the application. Furthermore, the terms "first," "second," "third," and the like are used for descriptive purposes only and are not to be construed as indicating or implying relative importance. "vertical" is not strictly vertical but is within the tolerance of the error. "parallel" is not strictly parallel but within the tolerance of the error.

Reference in the specification to "an embodiment" means that a particular feature, structure, or characteristic described in connection with the embodiment can be included in at least one embodiment of the specification. The appearances of the phrase in various places in the specification are not necessarily all referring to the same embodiment, nor are separate or alternative embodiments mutually exclusive of other embodiments. It is explicitly and implicitly understood by one skilled in the art that the embodiments described herein can be combined with other embodiments.

The directional terms used in the following description are intended to refer to directions shown in the drawings, and are not intended to limit the specific structure of the present application. In the description of the present application, it should also be noted that, unless expressly stated or limited otherwise, the terms "mounted," "connected," and "connected" are to be construed broadly and include, for example, fixed and removable connections as well as integral connections; may be directly connected or indirectly connected through an intermediate. The specific meaning of the above terms in the present application can be understood as appropriate by one of ordinary skill in the art.

In the present application, the battery cell may include a lithium ion secondary battery, a lithium ion primary battery, a lithium sulfur battery, a sodium lithium ion battery, a sodium ion battery, a magnesium ion battery, or the like, which is not limited in the embodiments of the present application. The battery cell may be a cylinder, a flat body, a rectangular parallelepiped, or other shapes, which is not limited in the embodiments of the present application. The battery cells are generally divided into three types in an encapsulation manner: the cylindrical battery monomer, the square battery monomer and the soft package battery monomer are not limited in the embodiment of the application.

Reference to a battery in embodiments of the present application refers to a single physical module that includes one or more battery cells to provide higher voltage and capacity. For example, the battery referred to in the present application may include a battery module or a battery pack, etc. Batteries generally include a case for enclosing one or more battery cells. The box can avoid liquid or other foreign matters to influence the charge or discharge of battery cells.

The battery monomer comprises an electrode assembly and electrolyte, wherein the electrode assembly comprises a positive plate, a negative plate and an isolating membrane. The single battery mainly depends on metal ions to move between the positive plate and the negative plate to work. The positive plate comprises a positive current collector and a positive active substance layer, wherein the positive active substance layer is coated on the surface of the positive current collector, the current collector which is not coated with the positive active substance layer protrudes out of the current collector which is coated with the positive active substance layer, and the current collector which is not coated with the positive active substance layer is laminated to be used as a positive electrode lug. Taking a lithium ion battery as an example, the material of the positive electrode current collector may be aluminum, and the positive electrode active material may be lithium cobaltate, lithium iron phosphate, ternary lithium, lithium manganate, or the like. The negative plate comprises a negative current collector and a negative active substance layer, the negative active substance layer is coated on the surface of the negative current collector, the current collector which is not coated with the negative active substance layer protrudes out of the current collector which is coated with the negative active substance layer, and the current collector which is not coated with the negative active substance layer is laminated to be used as a negative pole tab. The material of the negative electrode collector may be copper, and the negative electrode active material may be carbon, silicon, or the like. The material of the isolation film may be PP (polypropylene) or PE (polyethylene). In addition, the electrode assembly may have a winding structure or a lamination structure, and the embodiment of the present application is not limited thereto.

The present inventors have noted that the stability and safety of the battery cell are important, and the reliability of the structural strength of the battery cell, which serves as a load-bearing member, directly affects the safety and reliability of the battery. After further investigation, it was found that the bottom wall of the housing acts as the main load-bearing site, and its structural strength has a greater impact on the housing. Because the thickness of the bottom wall and the side wall of the conventional battery monomer shell is consistent, the overall strength of the battery monomer shell is reduced, and the stability and the safety of the battery monomer are reduced.

In view of this, the present application provides a technical solution, in which a housing of a battery cell includes a bottom wall and at least one side wall, the side wall and the bottom wall enclose a receiving cavity for receiving an electrode assembly of the battery cell, and a thickness of the bottom wall is greater than a thickness of the side wall. Among the above-mentioned scheme, set up the diapire of the free casing of battery for being greater than the thickness of lateral wall, the support intensity of multiplicable diapire improves the bulk strength of casing, improves the stability and the security of battery. And the thickness of the side wall is thinner, and after a plurality of battery monomers are arranged side by side, the volume of the battery module can be reduced, and the volume energy density of the whole battery is increased.

The battery cell disclosed in the embodiment of the present application can be used in, but not limited to, an electric device for a vehicle, a ship, an aircraft, or the like. The power supply system with the electric device formed by the battery monomer, the battery and the like disclosed by the application can be used, so that the stability of the performance of the battery is favorably improved, and the service life of the battery is prolonged.

The embodiment of the application provides an electric device using a battery as a power supply, wherein the electric device can be but is not limited to a mobile phone, a tablet, a notebook computer, an electric toy, an electric tool, a battery car, an electric automobile, a ship, a spacecraft and the like. The electric toy may include a stationary or mobile electric toy, such as a game machine, an electric car toy, an electric ship toy, an electric airplane toy, and the like, and the spacecraft may include an airplane, a rocket, a space shuttle, a spacecraft, and the like.

For convenience of description, the following embodiments take an example in which a power consuming apparatus according to an embodiment of the present application is a vehicle 1000.

Referring to fig. 1, fig. 1 is a schematic structural diagram of a vehicle 1000 according to some embodiments of the present disclosure. The vehicle 1000 may be a fuel automobile, a gas automobile, or a new energy automobile, and the new energy automobile may be a pure electric automobile, a hybrid electric automobile, or an extended range automobile, etc. The battery 100 is provided inside the vehicle 1000, and the battery 100 may be provided at the bottom or the head or the tail of the vehicle 1000. The battery 100 may be used for power supply of the vehicle 1000, for example, the battery 100 may serve as an operation power source of the vehicle 1000. The vehicle 1000 may further include a controller 200 and a motor 300, the controller 200 being configured to control the battery 100 to supply power to the motor 300, for example, for starting, navigation, and operational power requirements while the vehicle 1000 is traveling.

In some embodiments of the present application, the battery 100 may be used not only as an operating power source of the vehicle 1000, but also as a driving power source of the vehicle 1000, instead of or in part of fuel or natural gas, to provide driving power for the vehicle 1000.

Referring to fig. 2, fig. 2 is an exploded view of a battery 100 according to some embodiments of the present disclosure. The battery 100 includes a case 10 and a battery cell 20. In some embodiments, the case 10 may include an upper cover 10a and a lower cover 10b, the upper cover 10a and the lower cover 10b cover each other, and the upper cover 10a and the lower cover 10b together define a receiving space for receiving the battery cell 20. The lower cover 10b may be a hollow structure with an open end, the upper cover 10a may be a plate-shaped structure, and the upper cover 10a covers the open side of the lower cover 10b, so that the upper cover 10a and the lower cover 10b define an accommodating space together; the upper cover 10a and the lower cover 10b may be both hollow structures with one side open, and the open side of the upper cover 10a may cover the open side of the lower cover 10 b. Of course, the casing 10 formed by the upper cover 10a and the lower cover 10b may have various shapes, for example, a cylindrical body, a rectangular parallelepiped, etc.

Fig. 3 is a schematic structural view of the battery module 400 shown in fig. 2. In the battery 100, the number of the battery cells 20 may be multiple, and the multiple battery cells 20 may be connected in series or in parallel or in series-parallel, where in series-parallel refers to both series connection and parallel connection among the multiple battery cells 20. The plurality of battery cells 20 can be directly connected in series or in parallel or in series-parallel, and the whole formed by the plurality of battery cells 20 is accommodated in the box body 10; of course, the battery 100 may also be formed by connecting a plurality of battery cells 20 in series, in parallel, or in series-parallel to form a battery module 400, and then connecting a plurality of battery modules 400 in series, in parallel, or in series-parallel to form a whole, and accommodating them in the case 10. The battery 100 may further include other structures, for example, the battery 100 may further include a bus member for achieving electrical connection between the plurality of battery cells 20.

Wherein each battery cell 20 may be a secondary battery or a primary battery; but is not limited to, a lithium sulfur battery, a sodium ion battery, or a magnesium ion battery. The battery cell 20 may be cylindrical, flat, rectangular parallelepiped, or other shape.

Referring to fig. 4, fig. 4 is an exploded schematic view of a battery cell 20 according to some embodiments of the present disclosure. The battery cell 20 refers to the smallest unit constituting the battery. The battery cell 20 includes a case 21, an electrode assembly 22, and other functional components. The end cap 21 refers to a member that covers an opening of the case 22 to isolate the internal environment of the battery cell 20 from the external environment. Without limitation, the shape of the end cap 21 may be adapted to the shape of the housing 22 to fit the housing 22. Alternatively, the end cap 21 may be made of a material (e.g., an aluminum alloy) having a certain hardness and strength, so that the end cap 21 is not easily deformed when being impacted, and the battery cell 20 may have a higher structural strength and improved safety. The end cap 21 may be provided with functional components such as the electrode terminals 26. The electrode terminals 26 may be used to electrically connect with the electrode assembly 23 for outputting or inputting electric energy of the battery cells 20. In some embodiments, the end cap 21 may further be provided with a pressure relief mechanism for relieving the internal pressure when the internal pressure or temperature of the battery cell 20 reaches a threshold value. The material of the end cap 21 may also be various, such as copper, iron, aluminum, stainless steel, aluminum alloy, plastic, etc., which is not limited in this embodiment. In some embodiments, insulation may also be provided on the inside of the end cap 21, which may be used to isolate the electrical connection components within the housing 22 from the end cap 21 to reduce the risk of short circuits. Illustratively, the insulator may be plastic, rubber, or the like.

The case 21 is a component for forming an internal environment of the battery cell 20, wherein a receiving cavity 21a is formed to receive the electrode assembly 22, an electrolyte, and other components. The housing 21 may be of various shapes and various sizes, such as a rectangular parallelepiped, a cylindrical shape, a hexagonal prism shape, and the like. Specifically, the shape of the case 21 may be determined according to the specific shape and size of the electrode assembly 22. The material of the housing 21 may be various, such as copper, iron, aluminum, stainless steel, aluminum alloy, plastic, etc., and the embodiment of the present invention is not limited thereto.

The electrode assembly 22 is a component of the battery cell 20 in which electrochemical reactions occur. One or more electrode assemblies 22 may be contained within the case 21. The outer surface of the electrode assembly 22 may be provided with an insulating film 24 to perform insulation protection between the battery cells 20, so that the electrode assembly 22 is mainly formed by winding or stacking a positive electrode sheet and a negative electrode sheet, and a separator is generally disposed between the positive electrode sheet and the negative electrode sheet. The portions of the positive and negative electrode tabs having the active material constitute the main body of the electrode assembly 22, and the portions of the positive and negative electrode tabs having no active material each constitute a tab. The positive electrode tab and the negative electrode tab can be positioned at one end of the main body together or at two ends of the main body respectively.

In a first aspect, please refer to fig. 5 to 7 in combination, fig. 5 is a schematic structural diagram of a housing according to some embodiments of the present application; FIG. 6 is a schematic view of the housing of FIG. 5 at another angle; fig. 7 is an enlarged view of a portion a of fig. 6. The embodiment of the application provides a housing 22 of a battery cell 20, the housing 22 includes a bottom wall 30 and at least one side wall 40, the side wall 40 and the bottom wall 30 enclose a receiving cavity 22a for receiving an electrode assembly 23 of the battery cell 20, and the thickness of the bottom wall 30 is greater than that of the side wall 40.

The bottom wall 30 is disposed opposite to the opening of the housing 22, and the end cap 21 covers the opening. If the housing 22 is cylindrical, the housing 22 includes a bottom wall 30 and a side wall 40, the side wall 40 being circumferentially disposed around the bottom wall 30. If the housing 22 has a rectangular parallelepiped or hexagonal prism-shaped polygonal structure, the housing 22 includes a bottom wall 30 and a plurality of side walls 40, the plurality of side walls 40 are connected in sequence, and the bottom wall 30 and the plurality of side walls 40 jointly enclose to form an accommodating cavity 22a. The bottom wall 30 is adapted to contact the bottom of the electrode assembly 23, and has an upward supporting force against the battery cell 20. The side walls 40 are used to contact the side portions of the electrode assembly 23, and when a plurality of battery cells 20 are arranged side by side, the side walls 40 of adjacent battery cells 20 contact each other, so that the electrode assembly 23 is stably applied with the force of the side walls 40.

In the above solution, the bottom wall 30 of the housing 22 of the battery cell 20 is set to be thicker than the side wall 40, so that the supporting strength of the bottom wall 30 can be increased, the overall strength of the housing 22 can be improved, and the stability and safety of the battery 100 can be improved. In addition, since the side wall 40 is thin, the volume of the battery 100 module can be reduced and the volumetric energy density of the entire battery 100 can be increased when the plurality of battery cells 20 are arranged side by side.

In some embodiments, the housing 22 further includes a connecting wall 50, the connecting wall 50 for connecting the bottom wall 30 and the side wall 40; at least a portion of the connecting wall 50 is arcuate.

In the above solution, the connecting wall 50 is located in a sector area shown by a dotted line in fig. 7, the connecting wall 50 connecting the bottom wall 30 and the side wall 40 is set to be arc-shaped, the bottom wall 30 and the side wall 40 smoothly transition, so as to avoid a sharp corner between the bottom wall 30 and the side wall 40, reduce cracks of the connecting wall 50, prevent the connecting wall 50 from breaking, and increase the strength of the housing 22 of the battery cell 20.

Alternatively, if the housing 22 has a rectangular parallelepiped or hexagonal prism-shaped polygonal structure, the housing 22 includes a bottom wall 30 and a plurality of sidewalls 40, and an arc transition connection may be disposed between two adjacent sidewalls 40 to prevent cracks from occurring between the sidewalls 40, thereby further enhancing the strength of the housing 22.

In some embodiments, the connecting wall 50 includes a first wall 51 and a second wall 52, the first wall 51 is disposed close to the accommodating cavity 22a, the second wall 52 is disposed opposite to the first wall 51 and is located on a side of the first wall 51 far away from the accommodating cavity 22a, and the first wall 51 and the second wall 52 are respectively in an arc shape protruding away from the accommodating cavity 22a.

In the above solution, the connecting wall 50 has the first wall surface 51 and the second wall surface 52 that are arranged oppositely, the first wall surface 51 is arranged toward the accommodating cavity 22a, the second wall surface 52 is arranged away from the accommodating cavity 22a, and the first wall surface 51 and the second wall surface 52 are arranged to protrude in the direction away from the accommodating cavity 22a, so as to avoid occupying the internal volume of the casing 22 and provide more accommodating space for the electrode assembly 23.

In some embodiments, the connecting wall 50 satisfies the following equation: t ≦ R2-R1 ≦ U, where T is the thickness of the sidewall 40, U is the thickness of the bottom wall 30, and R1 and R2 are the bending radii of the first wall 51 and the second wall 52, respectively.

Since the thickness of the bottom wall 30 is greater than that of the side wall 40, the thickness of the connecting wall 50 is gradually reduced from the bottom wall 30 toward the side wall 40. The radius of curvature of the second wall 52 is larger than that of the first wall 51, and the thickness of the connecting wall 50 is determined by the difference between the radii of curvature of the first wall 51 and the second wall 52, so that the difference between the radii of curvature of the first wall 51 and the second wall 52 needs to be set reasonably.

In the above scheme, the difference between the bending radii of the second wall surface 52 and the first wall surface 51 is greater than or equal to the thickness of the side wall 40 and less than or equal to the thickness of the bottom wall 30, so that the thickness of the connecting wall 50 is within a proper range, the thickness of the connecting wall 50 is ensured to be large, cracks of the connecting wall 50 are avoided from being broken, the thickness of the connecting wall 50 is prevented from being too large, the difficulty in implementing the process is avoided, or the difficulty in installing the electrode assembly 23 is increased.

In some embodiments, the first wall 51 has a radius of curvature of 0.5mm to 1.5mm.

If the bending radius of the first wall surface 51 is too small, the manufacturing process of the housing 22 is difficult to be realized; if the bending radius of the first wall surface 51 is too large, the volume of the accommodating chamber 22a inside the case 22 is reduced, and the volumetric energy density of the battery cell 20 is reduced.

In the above solution, the bending radius of the first wall surface 51 is in a proper range, which not only facilitates the process drawing of the material of the housing 22, but also prevents the bending radius of the first wall surface 51 from being too large, and ensures that the volume energy density of the battery cell 20 is large.

In some embodiments, the housing 22 has a vickers hardness of less than 95.

The Vickers hardness is that a diamond regular pyramid indenter with an included angle of 136 degrees between opposite surfaces is used to press in the surface of a sample to be tested under the action of a specified load F, the load is removed after the time is kept, the diagonal length d of an indentation is measured, the surface area of the indentation is further calculated, and finally the average pressure on the surface area of the indentation is calculated, namely the Vickers hardness value of the metal, which is expressed by a symbol HV. In the actual measurement, the measured hardness value is obtained by directly looking up the table according to the measured d value without calculation.

In the above solution, the casing 22 is made of a material with a small vickers hardness, such as aluminum, aluminum alloy, and the like, for example, the cuboid casing 22 shown in fig. 5 to 7, the vickers hardness of the casing 22 is small, and the ductility of the material of the casing 22 is good, which facilitates the stretching of the material in the process manufacturing process of the casing 22.

In some embodiments, the bottom wall 30 includes a first inner surface 31 and a first outer surface 32 that are oppositely disposed, the first inner surface 31 being disposed adjacent to the receiving cavity 22a; the side wall 40 includes a second inner surface 41 and a second outer surface 42 which are oppositely arranged, the second inner surface 41 is arranged near the accommodating cavity 22a; the first wall 51 is tangent to the first inner surface 31 and the second inner surface 41, and the second wall 52 is disposed to project from the first wall 51 in a direction away from the accommodating chamber 22a. Virtual arcs tangent to the first outer surface 32 and the second outer surface 42 are provided to protrude in a direction away from the first wall surface 51.

Since the housing 22 of this embodiment is made of a material with a small vickers hardness, such as aluminum or aluminum alloy, for example, the rectangular parallelepiped housing 22, the connecting wall 50 is thickened to enhance the strength thereof. The first inner surface 31 and the second inner surface 41 are connected by a first wall 51 and the first outer surface 32 and the second outer surface 42 are connected by a second wall 52. The R-angle is a rounded corner of an arc tangent to two intersecting straight lines, while the connecting wall 50 of the present embodiment is a deformed R-angle. The first wall 51 is a natural transition arc tangent to the first inner surface 31 and the second inner surface 41, respectively, and the second wall 52 is disposed to protrude in a direction away from the accommodating cavity 22a relative to the first wall 51, that is, the second wall 52 is disposed to protrude in a direction away from the first wall 51 relative to a virtual arc, which is a virtual surface tangent to the first outer surface 32 and the second outer surface 42, respectively, so that the thickness of the connecting wall 50 is increased, the volume of the accommodating cavity 22a inside the housing 22 is ensured to be larger, and the volumetric energy density of the battery cell 20 is not affected.

The "virtual arc" is a virtual structure, and is not a real arc surface that actually exists, but a term used to express the shape of the second wall surface 52.

As shown in FIG. 7, in some embodiments, the dimension H of the second wall 52 in a direction perpendicular to the bottom wall 30 is 1-5 mm.

The dimension of the second wall surface 52 in the direction perpendicular to the bottom wall 30 is the height dimension of the second wall surface 52. If this dimension is too small, sharp corners tend to be formed between the second wall surface 52 and the side wall 40. Since the shell 22 is generally made of the shell 22 material by a stretching process, if the size is too large, the average thickness of the connecting wall 50 during the stretching process is too small, and the strength of the connecting wall 50 cannot be ensured.

In the above scheme, the size range of the second wall surface 52 in the direction perpendicular to the bottom wall 30 is proper, a sharp corner can be prevented from being formed between the second wall surface 52 and the side wall 40, and the second wall surface 52 is prevented from being too large in size, so that the connecting wall 50 becomes thinner gradually in the process of preparing and stretching the shell 22, the minimum wall thickness of the connecting wall 50 is smaller than the thickness of the side wall 40, and the strength of the connecting wall 50 is ensured.

In some embodiments, the minimum wall thickness of the connecting wall 50 is greater than or equal to the thickness of the side wall 40.

Because the thickness of the bottom wall 30 is greater than that of the side wall 40, the thickness of the connecting wall 50 is gradually reduced from the bottom wall 30 to the side wall 40, and the connecting wall 50 has a structure with gradually reduced thickness, so that the connecting wall 50 is smoother and cracks are reduced. The minimum wall thickness of the connecting wall 50 is the thickness of the joint of the connecting wall 50 and the side wall 40, and the minimum wall thickness of the connecting wall 50 is set to be larger than or equal to the thickness of the side wall 40, so that the smooth transition from the bottom wall 30 to the side wall 40 can be ensured, the thickness of the connecting wall 50 is further ensured, and the overall strength of the shell 22 is improved.

Further, the second wall surface 52 has a bending radius of 2 to 5mm. If the bending radius of the second wall 52 is too small, the manufacturing process of the housing 22 is difficult to be implemented; if the bending radius of the second wall surface 52 is too large, the average thickness of the connecting wall 50 during the stretching process is too small, and the strength of the connecting wall 50 cannot be ensured. Therefore, the bending radius of the second wall 52 of this embodiment is in a suitable range, which not only facilitates the process implementation, but also ensures the strength of the connecting wall 50.

In other embodiments, please refer to fig. 8 to 10 in combination, fig. 8 is a schematic structural diagram of a housing according to other embodiments of the present application; FIG. 9 is a schematic view of another angle of the housing of FIG. 8;

fig. 10 is an enlarged view of a portion a of fig. 9. The vickers hardness of the casing 22 is 95 to 200, and the casing 22 may be made of a material having a relatively large vickers hardness, such as stainless steel, for example, the cylindrical casing 22 shown in fig. 8, so that the overall strength of the casing 22 is improved.

More specifically, the bottom wall 30 includes a first inner surface 31 and a first outer surface 32 which are oppositely arranged, the first inner surface 31 is arranged near the accommodating cavity 22a; the side wall 40 includes a second inner surface 41 and a second outer surface 42 which are oppositely arranged, the second inner surface 41 is arranged near the accommodating cavity 22a; the first wall 51 is tangent to the first inner surface 31 and the second inner surface 41, respectively, and the second wall 52 is tangent to the first outer surface 32 and the second outer surface 42, respectively.

Since the housing 22 is made of a material with a relatively high vickers hardness, such as stainless steel, and the like, the structural strength of the present embodiment is relatively high, so that the connecting wall 50 does not need to be thickened, and the connecting wall 50 only needs to be a rounded corner, i.e., an R-corner, of an arc tangent to the bottom wall 30 and the side wall 40, respectively.

In the above solution, the first inner surface 31 and the second inner surface 41 are connected by the first wall 51, and the first outer surface 32 and the second outer surface 42 are connected by the second wall 52. Due to the larger vickers hardness of the shell 22, the first wall surface 51 is arranged to be tangent to the first inner surface 31 and the second inner surface 41, respectively, the second wall surface 52 is arranged to be tangent to the first outer surface 32 and the second outer surface 42, respectively, and both the first wall surface 51 and the second wall surface 52 are natural transition arcs, that is, the connecting wall 50 does not need thickening treatment, thereby facilitating the process preparation.

Further, the second wall surface 52 has a bending radius of 1 to 2mm. If the radius of curvature of the second wall 52 is too small. Since the housing 22 of the present embodiment is made of a material with a relatively high vickers hardness, the connecting wall 50 is designed as a round corner, and a thickening process is not required, so that the second wall surface 52 does not need to be protruded in a direction away from the first wall surface 51. The second wall 52 of the present embodiment has a smaller radius of curvature than the embodiment using the housing 22 having a vickers hardness of less than 95.

In the above solution, the bending radius of the second wall surface 52 is in a suitable range, which not only facilitates the stretching of the material of the housing 22 during the manufacturing process, but also avoids the phenomenon that the bending radius of the second wall surface 52 is too large, which causes a sharp corner between the second wall surface 52 and the sidewall 40.

In a second aspect, the present embodiment provides a battery cell 20, which includes an electrode assembly 23 and the case 22 of any of the above embodiments, wherein the electrode assembly 23 is accommodated in the accommodating cavity 22a.

In a third aspect, an embodiment of the present application provides a battery 100 including the battery cell 20 described above.

In a fourth aspect, an embodiment of the present application provides an electric device, which includes the above battery 100, where the battery 100 is used to provide electric energy.

According to some embodiments of the present application, there is provided a case 22 of a battery cell 20, the case 22 includes a bottom wall 30 and at least one side wall 40, the side wall 40 and the bottom wall 30 enclose a receiving cavity 22a for receiving an electrode assembly 23 of the battery cell 20, and a thickness of the bottom wall 30 is greater than a thickness of the side wall 40. The housing 22 further comprises a connecting wall 50, the connecting wall 50 being used to connect the bottom wall 30 and the side wall 40; at least a portion of the connecting wall 50 is arcuate. The connecting wall 50 includes a first wall 51 and a second wall 52, the first wall 51 is disposed close to the accommodating cavity 22a, the second wall 52 is disposed opposite to the first wall 51 and is located on a side of the first wall 51 away from the accommodating cavity 22a, and the first wall 51 and the second wall 52 are respectively in an arc shape protruding away from the accommodating cavity 22a. The bottom wall 30 includes a first inner surface 31 and a first outer surface 32 which are oppositely arranged, the first inner surface 31 is arranged near the accommodating cavity 22a; the side wall 40 includes a second inner surface 41 and a second outer surface 42 which are oppositely arranged, the second inner surface 41 is arranged near the accommodating cavity 22a; the first wall 51 is tangent to the first inner surface 31 and the second inner surface 41, respectively, and the second wall 52 is disposed to protrude in a direction away from the first wall 51 with respect to a virtual arc tangent to the first outer surface 32 and the second outer surface 42, respectively.

Finally, it should be noted that: the above embodiments are only used for illustrating the technical solutions of the present application, and not for limiting the same; although the present application has been described in detail with reference to the foregoing embodiments, it should be understood by those of ordinary skill in the art that: the technical solutions described in the foregoing embodiments may still be modified, or some or all of the technical features may be equivalently replaced; such modifications and substitutions do not depart from the spirit and scope of the present disclosure, and the present disclosure should be construed as being covered by the claims and the specification. In particular, the technical features mentioned in the embodiments can be combined in any way as long as there is no structural conflict. The present application is not intended to be limited to the particular embodiments disclosed herein, but rather to cover all embodiments falling within the scope of the appended claims.

Claims (15)

1. A battery cell housing, the housing comprising:

a bottom wall; and

the side wall and the bottom wall enclose a containing cavity for containing an electrode assembly of the battery cell, and the thickness of the bottom wall is larger than that of the side wall.

2. The housing of claim 1, further comprising a connecting wall for connecting the bottom wall and the side wall; at least a portion of the connecting wall is arcuate.

3. The housing of claim 2, wherein the connecting wall comprises:

a first wall surface disposed adjacent to the receiving cavity;

the second wall face is opposite to the first wall face and is located on one side, far away from the containing cavity, of the first wall face, and the first wall face and the second wall face are respectively in an arc shape protruding in the direction far away from the containing cavity.

4. The housing of claim 3, wherein the connecting wall satisfies the following equation: and T is more than or equal to R2 and R1 is more than or equal to U, wherein T is the thickness of the side wall, U is the thickness of the bottom wall, and R1 and R2 are the bending radiuses of the first wall surface and the second wall surface respectively.

5. The housing of claim 3, wherein the first wall has a radius of curvature of 0.5mm to 1.5mm.

6. The housing of claim 3, wherein the housing has a Vickers hardness of less than 95.

7. The housing of claim 6, wherein the bottom wall includes a first inner surface and a first outer surface disposed opposite, the first inner surface disposed proximate to the receiving cavity;

the side wall comprises a second inner surface and a second outer surface which are oppositely arranged, and the second inner surface is arranged close to the accommodating cavity;

the first wall surface is tangent to the first inner surface and the second inner surface respectively, and the second wall surface is arranged in a protruding mode relative to the first wall surface in the direction away from the containing cavity.

8. The housing of claim 7, wherein the second wall surface has a dimension in a direction perpendicular to the bottom wall of 1 to 5mm.

9. The housing of claim 6, wherein the minimum wall thickness of the connecting wall is greater than or equal to the thickness of the side wall.

10. The housing of claim 3, wherein the housing has a Vickers hardness of 95 to 200.

11. The housing of claim 10, wherein the bottom wall includes a first inner surface and a first outer surface disposed opposite, the first inner surface disposed proximate to the receiving cavity;

the side wall comprises a second inner surface and a second outer surface which are oppositely arranged, and the second inner surface is arranged close to the accommodating cavity;

the first wall surface is tangent to the first inner surface and the second inner surface, respectively, and the second wall surface is tangent to the first outer surface and the second outer surface, respectively.

12. The housing of claim 10, wherein the second wall has a radius of curvature of 1 to 2mm.

13. A battery cell, comprising:

an electrode assembly; and

the case according to any one of claims 1 to 12, wherein the electrode assembly is accommodated in the accommodation chamber.

14. A battery comprising the cell of claim 13.

15. An electrical device comprising a battery according to claim 14 for providing electrical energy.

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