Housing, casing of battery, battery, electrical apparatus, and method for processing housing

Abstract

A housing (21), a casing (2) of a battery (100), a battery (100), an electrical apparatus, and a method for processing a housing (21), relating to the technical field of batteries. The housing (21) is formed with an accommodating cavity (21a) and a mounting port (21b) in communication with the accommodating cavity (21a), the accommodating cavity (21a) is used for accommodating a bare cell (1), a housing wall of the housing (21) comprises a side wall and an end wall, a first end of the side wall encloses to form the mounting port (21b), the end wall is arranged at a second end of the side wall, the end wall and the side wall jointly define the semi-closed accommodating cavity (21a), the side wall is formed with a first region (21c) and a second region (21d), and the hardness of the first region (21c) is lower than the hardness of the second region (21d).

Description

Shell, battery case, battery, electric device and method for processing shell

[0001] Cross-reference to Related Applications

[0002] The present disclosure is based on and claims priority to Chinese Patent Application No. 202410217408.8, filed on February 27, 2024, entitled "Shell, battery case, battery, electric device and method for processing shell", the entire contents of which are incorporated herein by reference. TECHNICAL FIELD

[0003] The present disclosure relates to the technical field of batteries, and in particular to a shell, a battery case, a battery, an electric device and a method for processing a shell. BACKGROUND

[0004] New energy batteries are increasingly widely used in life and industry. New energy batteries are not only applied to energy storage power systems such as hydroelectric, thermal, wind and solar power stations, but also widely used in electric bicycles, electric motorcycles, electric vehicles and other electric vehicles.

[0005] In related technologies, a bare battery cell is arranged in the shell of the battery. During the charging and discharging process of the battery, the bare battery cell will expand, which can easily cause the shell to deform and crack.

[0006] SUMMARY

[0007] Therefore, the embodiments of the present disclosure aim to provide a shell, a battery case, a battery, an electric device and a method for processing a shell, which can reduce the probability of shell cracking.

[0008] To achieve the above-mentioned purpose, the technical solutions of the embodiments of the present disclosure are as follows:

[0009] In one aspect, the present disclosure discloses a shell. The shell forms an accommodating cavity and a mounting opening in communication with the accommodating cavity. The accommodating cavity is used to accommodate a bare battery cell. The shell wall of the shell includes a side wall and an end wall. The first end of the side wall is surrounded to form the mounting opening. The end wall is arranged at the second end of the side wall and is surrounded together with the side wall to form a semi-closed accommodating cavity. The side wall forms a first region and a second region. The hardness of the first region is lower than the hardness of the second region.

[0010] In the technical scheme, the accommodating cavity and the mounting port in communication with the accommodating cavity are arranged in the shell, so that the bare battery cell can be placed into the accommodating cavity from the mounting port, thereby protecting the bare battery cell to some extent and prolonging the service life of the bare battery cell. The first area and the second area are formed in the shell wall, the hardness of the first area is set to be lower than the hardness of the second area, so that, after the bare battery cell expands, the first area with lower hardness can absorb and disperse the force of the bare battery cell on the preset shell wall, thereby reducing the risk of cracking of the shell and improving the safety.

[0011] In an embodiment, the shell wall with the largest area on the side wall is the preset shell wall, and the first area is formed at least in the preset shell wall.

[0012] In the technical scheme, after the bare battery cell expands, the preset shell wall is the largest force application object of the bare battery cell because the preset shell wall is the shell wall with the largest area. By arranging the first area at least in the preset shell wall with the largest area, the force of the bare battery cell on the shell can be better absorbed and dispersed, so as to reduce the risk of cracking of the shell.

[0013] In an embodiment, the ratio of the hardness of the first area to the hardness of the second area is between 0.3 and 0.8; or, the ratio of the hardness of the first area to the hardness of the second area is between 0.5 and 0.8.

[0014] In the technical scheme, by setting the appropriate hardness ratio, on the one hand, the shell can be provided with sufficient structural strength to protect the bare battery cell and prolong the service life of the bare battery cell; on the other hand, after the bare battery cell expands, the first area with lower hardness can reduce the force of the bare battery cell on the shell and reduce the risk of cracking of the shell, thereby improving the safety.

[0015] In an embodiment, the hardness of the first area and the hardness of the second area are both Brinell hardness.

[0016] In an embodiment, the material of the shell is aluminum, the hardness of the second area is between 35 HB and 65 HB, and the hardness of the first area is between 25 HB and 40 HB.

[0017] In the technical scheme, by setting the second area with appropriate hardness and the first area with appropriate hardness, the shell can be provided with sufficient structural strength and the risk of cracking of the shell can be reduced.

[0018] In an embodiment, the grain type of the second area is strip-shaped grain and / or band-shaped grain, and the grain type of the first area is columnar grain and / or equiaxed grain.

[0019] In the technical solution, the grain type of the second area is set as strip-shaped grains and / or ribbon-shaped grains, and the grain type of the first area is set as columnar grains and / or equiaxed grains, which indicates that the hardness of the first area is lower than that of the second area. This is because, during the crystallization process of the metal, the formation of columnar grains and equiaxed grains is hindered, resulting in that the boundaries between the grains become blurred and the crystal lattice structure is relatively disordered, while ribbon-shaped grains and strip-shaped grains are relatively easy to form, and the crystal lattice structure is relatively ordered. The crystal structure affects the mechanical properties of the metal, for example, a disordered crystal structure can reduce the hardness and strength and improve the toughness, and an ordered crystal lattice structure can increase the hardness and strength but reduce the toughness. That is, when the shell is subjected to the force exerted by the swelling of the bare battery cell, the disordered crystal structure can better absorb and disperse the force due to its high toughness, so as to reduce the expansion of cracks and the occurrence of breakage.

[0020] In an embodiment, the first area is arranged along the circumference of the mounting port.

[0021] In the technical solution, the arrangement of the first area along the circumference of the mounting port can increase the area of the first area. When the bare battery cell swells, the first area arranged circumferentially around the mounting port can better absorb and disperse the force exerted by the bare battery cell on the shell, reducing the occurrence of cracking at the mounting port and improving the stability of the shell.

[0022] In an embodiment, the distance between the first area on the preset shell wall and the circumference of the mounting port is not less than 50 mm; and / or, the distance between the first area on the preset shell wall and the circumference of the mounting port is a first distance, the distance between the preset shell wall and the circumference of the mounting port is a second distance, and the ratio of the first distance to the second distance is not less than 25%.

[0023] In the technical solution, by setting a suitable circumferential distance, the circumferential length of the first area can be extended to better absorb and disperse the force exerted by the swelling of the bare battery cell on the shell along the circumference, further reducing the risk of cracking. By setting a suitable ratio, the overall toughness of the preset shell wall can be improved while ensuring that the preset shell wall has sufficient structural strength, so as to absorb and disperse the force exerted by the swelling of the bare battery cell on the shell and reduce the occurrence of cracking.

[0024] In an embodiment, the direction perpendicular to the preset shell wall is a target direction, and the projection area of the first area in the target direction is smaller than the projection area of the second area.

[0025] In the technical solution, by setting the area of the first area to be smaller than the area of the second area, the shell can have high toughness while having sufficient structural strength, so as to absorb and disperse the force exerted by the swelling of the bare battery cell on the shell, reduce stress concentration, and reduce the risk of cracking.

[0026] In another aspect, the present disclosure provides a shell of a battery, which comprises a top cover and the shell according to any one of the above embodiments, and the top cover covers the mounting port.

[0027] In the above technical solution, the first area is arranged on the preset shell wall of the shell, and the hardness of the first area is smaller than that of the second area. In this way, the first area can absorb and disperse the force exerted by the swelling of the bare battery cell on the shell, reduce stress concentration at the mounting port, reduce the risk of cracking at the mounting port, and improve safety.

[0028] In an embodiment, the top cover is connected to the shell by welding, the hardness of the molten pool area formed by welding of the shell is not less than the hardness of the first area, the opening direction of the mounting port is the first direction, and the size of the first area along the first direction is not less than 0.2 mm.

[0029] In the above technical solution, the top cover is welded to the shell, and the hardness of the molten pool area is greater than that of the second area, so as to improve the connection strength between the top cover and the shell. By arranging the first area with a suitable size, the shell has sufficient structural strength and high toughness, so as to absorb and disperse the force exerted by the swelling of the bare battery cell on the shell, reduce stress concentration at the mounting port, reduce cracking at the mounting port, and improve the cycle swelling life of the shell under charging and discharging.

[0030] In an embodiment, the size of the first area along the first direction is not less than 1 mm.

[0031] In the above technical solution, by arranging the first area with a suitable size, the cracking at the mounting port can be reduced.

[0032] In an embodiment, the size of the first area along the first direction is not greater than half of the size of the shell along the first direction.

[0033] In the above technical solution, the shell has sufficient structural strength to protect the internal bare battery cell, and the toughness of the shell is improved to absorb and disperse the force exerted by the swelling of the bare battery cell on the shell, reduce cracking, and improve the cycle swelling life of the shell under charging and discharging.

[0034] In an embodiment, the opening direction of the mounting port is the first direction, and the molten pool area is located on the side of the first area facing the corresponding mounting port along the corresponding first direction.

[0035] In the above technical solution, the molten pool area is arranged between the mounting port and the first area along the first direction, so as to facilitate stable welding of the top cover to the shell and improve the connection strength, and the first area close to the molten pool area can reduce stress concentration at the molten pool area and reduce cracking at the molten pool area.

[0036] In an embodiment, the first region is located between the molten pool region and the second region along the first direction, and the first region continuously extends from the molten pool region to the second region.

[0037] In the technical solution, the first region is in contact with the second region and the molten pool region respectively, and the first region can be further heated and softened by the residual heat of the molten pool region, so that the hardness of the first region is lower and the toughness is better.

[0038] In an embodiment, the first region includes a first sub-region and a second sub-region, the first sub-region is adjacent to the molten pool region, and the first sub-region and the second sub-region are arranged at intervals along the first direction.

[0039] In the technical solution, the expansion of the bare battery cell can not only be absorbed and dispersed by the first sub-region, but also by the second sub-region, and the anti-cracking effect is better. The first sub-region and the second sub-region are arranged at intervals along the first direction, which means that the second sub-region can be set according to the position requirements to meet the needs in complex stress environment.

[0040] In an embodiment, the first sub-region and the second sub-region are arranged at intervals along the first direction, and the interval distance is between 0.05mm and 10mm.

[0041] In the technical solution, by setting a suitable interval distance, the second sub-region can be set according to requirements.

[0042] In another aspect, the disclosure also discloses a battery, which includes a bare battery cell and a shell according to any one of the above embodiments, and the bare battery cell is arranged in the accommodating cavity.

[0043] In the technical solution, the risk of cracking of the shell caused by the expansion of the bare battery cell can be reduced, and the service life of the battery can be improved.

[0044] In an embodiment, the interval distance between the first region and the bare battery cell along the opening direction of the mounting port is between 0.3mm and 7mm.

[0045] In the technical solution, by setting a suitable interval distance, the toughness of the shell can be improved, and the damage to the bare battery cell can be reduced, and the service life of the bare battery cell can be improved.

[0046] In an embodiment, the interval distance between the first region and the bare battery cell along the opening direction of the mounting port is between 1mm and 3mm.

[0047] In the technical solution, by setting a suitable interval distance, the damage to the bare battery cell can be reduced.

[0048] In an embodiment, the battery includes a lower plastic, the lower plastic is arranged on the side of the top cover facing the bare battery cell, and the interval distance between the lower plastic and the first region along the inside-outside direction is greater than 1mm.

[0049] In the technical solution, the lower plastic is arranged on the side of the top cover facing the bare battery cell, which can insulate and separate the top cover and the bare battery cell, avoiding direct contact between the top cover and the bare battery cell, thereby avoiding the risk of short circuit and battery damage. By setting an appropriate spacing distance, damage to the lower plastic can be reduced, the service life of the lower plastic can be improved, and the working stability is good.

[0050] In an embodiment, the spacing between the lower plastic and the first area in the inner-outer direction is between 1.2 mm and 5 mm.

[0051] In the technical solution, by setting an appropriate spacing distance, the damage to the lower plastic can be reduced.

[0052] In another aspect, the disclosure provides a battery as described above.

[0053] In the technical solution, due to the improvement of the safety of the battery, the safety of the electric device is also improved.

[0054] In another aspect, the disclosure provides a method for processing a shell, the method comprising:

[0055] Softening: at least heating and softening a preset shell wall of the shell to soften at least a second area of the preset shell wall into a first area;

[0056] The mounting port of the shell is in communication with the accommodating cavity of the shell, and the preset shell wall is arranged adjacent to the mounting port. The preset shell wall is the shell wall with the largest area of the shell.

[0057] In the technical solution, the preset shell wall of the shell is heated and softened to soften at least the second area of the preset shell wall into the first area. The hardness of the first area is lower than that of the second area. After the bare battery cell expands, the first area with lower hardness can absorb and disperse the force of the bare battery cell on the preset shell wall, thereby reducing the risk of cracking of the shell, and in turn reducing the probability of leakage of electrolyte in the shell, and improving the cycle expansion life of the shell under charging and discharging. The first area is softened by the second area, which can reduce the addition of new materials, and the shell has good integrity.

[0058] In an embodiment, the method further comprises:

[0059] Placing the bare battery cell into the softened shell;

[0060] Connecting the top cover to the shell containing the bare battery cell at the mounting port, so that the top cover blocks the bare battery cell in the accommodating cavity.

[0061] In the technical solution, the shell is softened first and then connected to the top cover, which can reduce damage to the bare battery cell when the softening operation is performed.

[0062] In one embodiment, before the softening step is performed, the method further comprises:

[0063] The top cover is connected with the shell containing the bare battery cell at the installation port, so that the top cover blocks the bare battery cell in the accommodation cavity.

[0064] In the above technical solution, before the softening step is performed, the top cover can be placed at the installation port, and then the shell and the top cover can be connected by welding to block the installation of the top cover and block the bare battery cell in the accommodation cavity. In this way, the position can be selected according to the softening requirement.

[0065] In one embodiment, at least the preset shell wall of the shell is heated and softened to soften at least part of the second area of the preset shell wall into the first area, comprising:

[0066] At least the target area of the preset shell wall of the shell is heated and softened to soften at least part of the second area of the preset shell wall into the first area, the target area is located between the bare battery cell and the installation port along the opening direction of the installation port, and the target area is arranged spaced apart from the bare battery cell along the opening direction of the installation port.

[0067] In the above technical solution, by heating and softening the target area between the bare battery cell and the installation port into the first area, and the hardness of the first area is lower than that of the second area, when the bare battery cell expands, the first area can absorb and disperse the force exerted by the bare battery cell, reduce the stress concentration at the installation port, and then reduce the risk of cracking at the installation port, and improve the cycle expansion life of the shell under charging and discharging. BRIEF DESCRIPTION OF DRAWINGS

[0068] FIG. 1 is a structural schematic diagram of a battery provided by an embodiment of the present disclosure;

[0069] FIG. 2 is a cutaway schematic diagram of FIG. 1;

[0070] FIG. 3 is an enlarged schematic diagram of A in FIG. 2;

[0071] FIG. 4 is a cutaway schematic diagram of the shell in FIG. 1;

[0072] FIG. 5 is an enlarged schematic diagram of C in FIG. 4;

[0073] FIG. 6 is a metallographic diagram of the second area;

[0074] FIG. 7 is a metallographic diagram of the first area;

[0075] FIG. 8 is a Vickers hardness spectrum of part of the shell;

[0076] FIG. 9 is a Brinell hardness spectrum of part of the shell;

[0077] FIG. 10 is a flowchart of a method for processing a shell provided by another embodiment of the present disclosure.

[0078] Battery 100; bare cell 1; shell 2; housing 21; accommodating cavity 21a; mounting port 21b; first region 21c; first sub-region 21c1; second sub-region 21c2; second region 21d; molten pool region 21e; first shell wall 211; second shell wall 212; third shell wall 213; top cover 22; pressure relief port 22a; liquid injection port 22b; electrode port 22c; lower plastic 3; first distance H1; second distance H2. DETAILED DESCRIPTION

[0079] The embodiments of the technical solutions of the present disclosure will be described in detail below in conjunction with the drawings. The following embodiments are only used to more clearly illustrate the technical solutions of the present disclosure, and therefore only serve as examples, and cannot limit the protection scope of the present disclosure.

[0080] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this disclosure belongs; the terms used herein are only for the purpose of describing specific embodiments and are not intended to limit the present disclosure; the terms "include" and "have" and any variations thereof in the specification and the above drawings description of the present disclosure are intended to cover non-exclusive inclusion.

[0081] In the description of the embodiments of the present disclosure, the technical terms "first", "second", "third" and the like 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 disclosure, the meaning of "a plurality of" is two or more, unless otherwise explicitly and specifically limited.

[0082] In this paper, the "embodiment" means that the specific features, structures or properties described in conjunction with the embodiment can be included in at least one embodiment of the present disclosure. The appearance of this phrase in the specification does not necessarily mean the same embodiment, nor is it an independent or alternative embodiment that is not mutually exclusive with other embodiments. The skilled person in the art explicitly and implicitly understands that the embodiments described herein can be combined with other embodiments.

[0083] In the description of the embodiments of the present disclosure, unless otherwise explicitly specified and limited, the technical terms "mounting", "connection", "fixing" and the like should be understood in a broad sense, for example, it can be fixedly connected, or it can be detachably connected, or it can be integrated; it can be mechanical connection, or it can be electrical connection; it can be directly connected, or it can be indirectly connected through an intermediate medium; it can be the internal communication of two elements or the interaction relationship between two elements. For those skilled in the art, the specific meaning of the above terms in the embodiments of the present disclosure can be understood according to the specific circumstances.

[0084] In the description of the embodiments of the present disclosure, unless explicitly defined and limited otherwise, the technical term "contact" should be interpreted broadly, which can be direct contact or contact through an intermediate medium layer, and can be contact between two objects in contact without interaction force or contact between two objects in contact with interaction force.

[0085] At present, new energy batteries are increasingly widely used in life and industry. New energy batteries are not only applied to energy storage power supply systems such as hydroelectric, thermal, wind and solar power stations, but also widely used in electric bicycles, electric motorcycles, electric vehicles and other electric vehicles. With the continuous expansion of the application field of power batteries, the market demand is also increasing.

[0086] As part of the inventive concept of the present disclosure, before describing the embodiments of the present disclosure, the reasons for the shell of the battery being prone to cracking in the related art are analyzed, and the technical solution of the embodiments of the present disclosure is obtained through reasonable analysis.

[0087] In the related art, the bare cell is located in the accommodating cavity of the shell. Taking the charging of a lithium ion battery as an example, during the charging process of the lithium ion battery, lithium ions will be released from the positive electrode and embedded in the negative electrode, which will cause the negative electrode layer spacing to increase, thereby causing the bare cell to expand. The expanded bare cell will squeeze the shell, causing it to deform and crack.

[0088] If a first area is provided on the shell wall of the shell, the hardness of the first area is less than the hardness of the second area. After the bare cell expands, the first area with lower hardness can absorb and disperse the force of the bare cell on the preset shell wall, thereby reducing the risk of cracking of the shell, and in turn reducing the probability of leakage of electrolyte in the shell, which is safe.

[0089] The scheme of the embodiments of the present disclosure can be but not limited to a hard-pack battery monomer, a battery module including a plurality of hard-pack battery monomers, or a battery pack including a hard-pack battery monomer or a battery module, and can also be applied to a soft-pack battery monomer, a battery module including a plurality of soft-pack battery monomers, or a battery pack including a soft-pack battery monomer or a battery module.

[0090] The battery monomer refers to a basic unit capable of realizing mutual conversion between chemical energy and electrical energy.

[0091] In the embodiments of the present disclosure, the battery monomer can be a secondary battery, which refers to a battery monomer that can be activated by charging after discharging to continue to use.

[0092] In the embodiments of the present disclosure, the battery cell can be a lithium ion battery, a sodium ion battery, a sodium lithium ion battery, a lithium metal battery, a sodium metal battery, a lithium-sulfur battery, a magnesium ion battery, a nickel-hydrogen battery, a nickel-cadmium battery, a lead-acid battery, etc., and the embodiments of the present disclosure are not limited thereto.

[0093] The bare cell refers to an electrochemical core in the battery, i.e., the cell. The bare cell contains a positive electrode and a negative electrode, and can store and release electrical energy.

[0094] The bare cell can be formed by winding or stacking the pole piece.

[0095] In one aspect, the present disclosure provides a shell, please refer to FIG. 1 to FIG. 9, the shell 21 is formed with a receiving cavity 21a and a mounting port 21b in communication with the receiving cavity 21a, the receiving cavity 21a is used for accommodating the bare cell 1, the shell wall of the shell 21 includes a side wall and an end wall, the first end of the side wall is surrounded to form the mounting port 21b, the end wall is arranged at the second end of the side wall and is surrounded together with the side wall to form a semi-closed receiving cavity 21a; the side wall is formed with a first area 21c and a second area 21d, and the hardness of the first area 21c is lower than the hardness of the second area 21d.

[0096] The shell 21 refers to a structure with a certain wall thickness, and the shell 21 is mainly used for accommodating the bare cell 1, forming a certain protection for the bare cell 1, and reducing the risk of damage of the bare cell 1 exposed to the outside.

[0097] For example, the shape of the shell 21 can be a cuboid or a cylinder. When the shape of the shell 21 is a cuboid, the corresponding battery 100 is a square battery, and when the shape of the shell 21 is a cylinder, the corresponding battery 100 is a cylindrical battery.

[0098] The receiving cavity 21a refers to the receiving space in the shell 21, which is used for accommodating the bare cell 1.

[0099] The mounting port 21b is in communication with the receiving cavity 21a, and the bare cell 1 can be placed into the receiving cavity 21a of the shell 21 through the mounting port 21b.

[0100] The first area 21c and the second area 21d both refer to the shell wall of the shell 21, which can be the inner wall of the shell 21 or the outer wall of the shell 21, and the difference is that the hardness of the first area 21c is less than the hardness of the second area 21d.

[0101] The semi-closed receiving cavity 21a refers to that the second end of the receiving cavity 21a is provided with an end wall for plugging, and the first end has a mounting port 21b.

[0102] The shell 21 provided by the embodiment of the present disclosure is provided with a containing cavity 21a and a mounting port 21b in communication with the containing cavity 21a, so that the bare battery cell 1 can be put into the containing cavity 21a from the mounting port 21b, so as to protect the bare battery cell 1 to some extent and improve the service life of the bare battery cell 1. The first area 21c and the second area 21d are formed on the shell wall of the shell 21, the hardness of the first area 21c is set to be lower than the hardness of the second area 21d, so that after the bare battery cell 1 expands, the first area 21c with lower hardness can absorb and disperse the force of the bare battery cell 1 on the preset shell wall, thereby reducing the risk of cracking of the shell 21 and improving the safety.

[0103] In an embodiment, the shell wall with the largest area on the side wall is the preset shell wall, and the first area 21c is formed at least on the preset shell wall.

[0104] In this way, after the bare battery cell 1 expands, since the preset shell wall is the shell wall with the largest area of the shell 21, the preset shell wall is the largest force object after the bare battery cell 1 expands, and by setting the first area 21c at least on the preset shell wall with the largest area, the force of the bare battery cell 1 on the shell 21 can be better absorbed and dispersed to reduce the risk of cracking of the shell 21.

[0105] For example, in an embodiment, referring to FIG. 1, the shell 21 has five shell walls, two of the five shell walls are first shell walls 211, the areas of the two first shell walls 211 are equal, two of the five shell walls are second shell walls 212, the areas of the two second shell walls 212 are equal, and the last one of the five shell walls is a third shell wall 213, the area of the second shell wall 212 and the area of the third shell wall 213 are both smaller than the area of the first shell wall 211, the two first shell walls 211 are arranged in a second direction, the two second shell walls 212 are arranged in a third direction, and the third shell wall 213 is connected to the two first shell walls 211 and the two second shell walls 212 in a first direction to jointly define the containing cavity 21a and the mounting port 21b, the two first shell walls 211 and the two second shell walls 212 form a side wall, and the third shell wall 213 is an end wall, the first shell wall 211 can be the preset shell wall, and the first direction, the second direction and the third direction are perpendicular to each other.

[0106] It should be noted that R1 in FIG. 1 can be the first direction, R2 can be the second direction, and R3 can be the third direction.

[0107] In an embodiment, referring to FIGS. 8 and 9, the ratio of the hardness of the first area 21c to the hardness of the second area 21d is between 0.3 and 0.8.

[0108] For example, the ratio of the hardness of the first region 21c to the hardness of the second region 21d can be 0.3, 0.35, 0.4, 0.45, 0.5, 0.55, 0.6, 0.65, 0.7, 0.75, or 0.8, and the like.

[0109] In this way, by setting a suitable hardness ratio, on the one hand, the shell 21 can be provided with sufficient structural strength to protect the bare battery cell 1 and improve the service life of the bare battery cell 1; on the other hand, after the bare battery cell 1 expands, the first region 21c with lower hardness can reduce the force of the bare battery cell 1 on the shell 21, thereby reducing the risk of cracking of the shell 21 and improving safety.

[0110] In an embodiment, the ratio of the hardness of the first region 21c to the hardness of the second region 21d is between 0.5 and 0.8.

[0111] For example, the ratio of the hardness of the first region 21c to the hardness of the second region 21d can be 0.5, 0.55, 0.6, 0.65, 0.7, 0.75, or 0.8, and the like.

[0112] In an embodiment, the hardness of the first region 21c and the hardness of the second region 21d are Brinell hardness.

[0113] It should be noted that HB is the unit of Brinell hardness.

[0114] In an embodiment, referring to FIG. 8 and FIG. 9, FIG. 8 is a Vickers hardness spectrum of a partial shell, and FIG. 9 is a Brinell hardness spectrum of a partial shell. The material of the shell 21 is aluminum, the hardness of the second region 21d is between 35 HB and 65 HB, and the hardness of the first region 21c is between 25 HB and 40 HB.

[0115] For example, the hardness of the second region 21d can be 35 HB, 40 HB, 45 HB, 50 HB, 55 HB, 60 HB, or 65 HB, and the hardness of the first region 21c can be 25 HB, 30 HB, 35 HB, or 40 HB, and the like.

[0116] Here, by setting the second region 21d with a suitable hardness and the first region 21c with a suitable hardness, not only can the shell 21 be provided with sufficient structural strength, but also the risk of cracking of the shell 21 can be reduced.

[0117] It should be noted that HB is the unit of Brinell hardness.

[0118] For example, in an embodiment, the hardness of the first region 21c can be 30 HB, and the hardness of the second region 21d can be 60 HB.

[0119] For example, in one embodiment, referring to Table 1, which is a table of mechanical properties of 3003 alloy, O, H12, H14, H16 or H18 is the material grade, and the hardness column in the table is the hardness before processing. For example, H14 has a hardness of 40 HB before being processed into the shell 21, and the hardness will be greater than 40 HB after being processed into the shell 21; and the hardness will be less than 40 HB after being softened into the first region 21c. For another example, H18 has a hardness of 55 HB before being processed into the shell 21, and the hardness will be greater than 55 HB after being processed into the shell 21; and the hardness will be less than 55 HB after being softened into the first region 21c.

[0120] Table 1 Mechanical properties of 3003 alloy

[0121] It should be noted that 3003 is an aluminum-manganese alloy.

[0122] It should be noted that the "O" state in the above table refers to the data of the annealed state of the corresponding aluminum alloy.

[0123] In one embodiment, referring to FIG. 6 and FIG. 7, FIG. 6 is a metallographic diagram of the second region, and FIG. 7 is a metallographic diagram of the first region. The grain type of the second region 21d is strip-shaped grain and / or band-shaped grain, and the grain type of the first region 21c is columnar grain and / or equiaxed grain.

[0124] For example, the grain type of the second region 21d can be strip-shaped grain, or the grain type of the second region 21d can be band-shaped grain, or the grain type of the second region 21d can be strip-shaped grain and band-shaped grain. The grain type of the first region 21c can be columnar grain, or the grain type of the first region 21c can be equiaxed grain, or the grain type of the first region 21c can be columnar grain and equiaxed grain.

[0125] Band-shaped grain refers to a grain type in which the grains are arranged in a band shape along a certain direction.

[0126] Strip-shaped grain refers to a grain type in which the grains grow along a certain specific direction to form a strip or fiber shape.

[0127] Columnar grain is a crystal form characterized by longitudinal extension and columnar shape.

[0128] Equiaxed grain refers to a grain type in which the grains have a small difference in size in all directions and have high symmetry. In the equiaxed crystal system, the three crystal axes are equal in length, and the angle between them is 90°.

[0129] In this way, by setting the grain type of the second area 21d to be strip-shaped and / or ribbon-shaped and setting the grain type of the first area 21c to be columnar-shaped and / or equiaxed-shaped, it is indicated that the hardness of the first area 21c is lower than that of the second area 21d, because the formation of columnar-shaped and equiaxed-shaped grains is hindered during the crystallization process of the metal, resulting in the boundaries between the grains becoming blurred and the lattice structure being relatively disordered, while the ribbon-shaped and strip-shaped grains are relatively easy to form and have a relatively ordered lattice structure. The crystal structure will affect the mechanical properties of the metal, for example, a disordered crystal structure will result in a decrease in hardness and strength and an increase in toughness, while an ordered lattice structure will make the hardness and strength higher, but will reduce the toughness. That is, when the shell 21 is subjected to the action force exerted by the expansion of the bare battery cell 1, the disordered crystal structure can better absorb and disperse the action force due to its higher toughness, so as to reduce the expansion of cracks and the occurrence of breakage.

[0130] For example, in an embodiment, the E point in FIG. 8 is lower in hardness because of the pores in the shell wall of the shell 21, but the grain type at this point is still strip-shaped and / or ribbon-shaped.

[0131] In an embodiment, the first area 21c is arranged to extend along the circumference of the mounting port 21b.

[0132] For example, the first area 21c can be arranged on the two first shell walls 211 and the two second shell walls 212 around the circumference of the mounting port 21b.

[0133] In this way, the area of the first area 21c can be increased, and when the bare battery cell 1 expands, the first area 21c arranged around the circumference of the mounting port 21b can better absorb and disperse the action force of the bare battery cell 1 on the shell 21, reducing the occurrence of cracking at the mounting port 21b and improving the stability of the work.

[0134] In an embodiment, referring to FIG. 1, the distance of the first area 21c on the preset shell wall along the circumference of the mounting port 21b is not less than 50 mm.

[0135] For example, the distance of the first area 21c on the preset shell wall along the circumference of the mounting port 21b can be 50 mm, 55 mm, 60 mm, 65 mm, 70 mm, 75 mm, 80 mm, 85 mm, 90 mm, 95 mm, or 100 mm, and the like.

[0136] In this way, by setting a suitable circumferential distance, the circumferential length of the first area 21c can be extended to better absorb and disperse the action force of the expansion of the bare battery cell 1 on the shell 21 along the circumference, further reducing the risk of cracking.

[0137] In one embodiment, referring to FIG. 1, the first distance H1 is a distance of the first region 21c along a circumference of the mounting opening 21b, and the second distance H2 is a distance of the preset shell wall along the circumference of the mounting opening 21b. The ratio of the first distance H1 to the second distance H2 is not less than 25%.

[0138] Referring to FIG. 1, the first distance H1 is a length of the first region 21c along a circumference of the mounting opening 21b. For example, the first distance H1 can be a length of the first region 21c along the third direction.

[0139] Referring to FIG. 1, the second distance H2 is a length of the preset shell wall along a circumference of the mounting opening 21b. For example, the second distance H2 can be a length of the preset shell wall along the third direction.

[0140] For example, the ratio of the first distance H1 to the second distance H2 can be 25%, 30%, 35%, 40%, 45%, 50%, 55%, 60%, 65%, 70%, 75%, 80%, 85%, 90%, 95%, or 100%, and the like.

[0141] In this way, by setting an appropriate ratio, the overall toughness of the preset shell wall can be improved while ensuring that the preset shell wall has sufficient structural strength, so as to absorb and disperse the force exerted by the swelling of the bare battery cell 1, and reduce the risk of cracking.

[0142] In one embodiment, the distance of the first region 21c along the circumference of the mounting opening 21b is not less than 50 mm, the distance of the first region 21c along the circumference of the mounting opening 21b is the first distance H1, the distance of the preset shell wall along the circumference of the mounting opening 21b is the second distance H2, and the ratio of the first distance H1 to the second distance H2 is not less than 25%.

[0143] That is, the distance of the first region 21c along the circumference of the mounting opening 21b is not less than 50 mm, and the distance of the preset shell wall along the circumference of the mounting opening 21b is not less than 200 mm. In this way, the ratio of the first distance H1 to the second distance H2 can be not less than 25%. In this way, the preset shell wall has sufficient structural strength to protect the bare battery cell 1 inside, and has relatively strong toughness to absorb and disperse the force exerted by the swelling of the bare battery cell 1, thereby reducing the risk of cracking.

[0144] In one embodiment, the direction perpendicular to the preset shell wall is the target direction, and the projection area of the first region 21c along the target direction is smaller than the projection area of the second region 21d.

[0145] For example, the target direction can be the second direction, and the projection area of the first region 21c along the second direction is smaller than the projection area of the second region 21d.

[0146] In this way, by setting the area of the first area 21c to be smaller than the area of the second area 21d, while meeting the requirement that the shell 21 has sufficient structural strength, the shell 21 can also have higher toughness to absorb and disperse the force exerted on it by the swelling of the bare battery cell 1, reduce stress concentration, and reduce the risk of cracking.

[0147] In another aspect, the shell 2 of the battery 100 according to an embodiment of the present disclosure includes the shell 21 according to any one of the above embodiments and a top cover 22 covering the mounting port 21b.

[0148] Here, during charging and discharging, the bare battery cell 1 will repeatedly swell, which can easily cause stress to be concentrated at the mounting port 21b where the top cover 22 is connected to the shell 21, and can easily cause cracking. Therefore, by providing the first area 21c on the preset shell wall of the shell 21, the hardness of the first area 21c is less than the hardness of the second area 21d. In this way, the first area 21c can absorb and disperse the force exerted on the shell 21 by the swelling of the bare battery cell 1, reduce stress concentration at the mounting port 21b, reduce the risk of cracking at the mounting port 21b, and have high safety.

[0149] For example, in an embodiment, as shown in FIG. 1, the top cover 22 is formed with a pressure relief port 22a, a liquid injection port 22b, and an electrode port 22c, all of which penetrate the top cover 22 along the first direction. When the top cover 22 is covered at the mounting port 21b, the pressure relief port 22a, the liquid injection port 22b, and the electrode port 22c are all in communication with the accommodation cavity 21a. The pressure relief port 22a is used to relieve the pressure in the accommodation cavity 21a after the bare battery cell 1 experiences thermal runaway, to avoid explosion. The liquid injection port 22b is used to inject electrolyte into the accommodation cavity 21a. The electrode port 22c facilitates electrical connection to the tabs of the bare battery cell 1.

[0150] In an embodiment, as shown in FIGS. 1 and 3, the top cover 22 is connected to the shell 21 by welding, the hardness of the molten pool area 21e formed by welding of the shell 21 is not less than the hardness of the first area 21c, the opening direction of the mounting port 21b is the first direction, and the dimension of the first area 21c along the first direction is not less than 0.2 mm.

[0151] The molten pool area 21e refers to the portion of the base material that is melted into a pool shape by the heat of the welding arc. It is a portion of liquid metal with a certain geometric shape formed on the welding part during welding.

[0152] Exemplarily, the top cover 22 is welded with the shell 21 at the mounting port 21b, and the shell 21 is welded to form a molten pool area 21e with a hardness not less than that of the first area 21c. The size of the first area 21c along the first direction can be represented as H3, which can be 0.2 mm, 0.3 mm, 0.4 mm, 0.5 mm, 0.6 mm, 0.7 mm, 0.8 mm, 0.9 mm, 1 mm, 3 mm, 5 mm, 8 mm, 10 mm, or 12 mm, and the like.

[0153] In this way, by welding the top cover 22 with the shell 21, the hardness of the molten pool area 21e is greater than that of the second area 21d, so as to improve the connection strength between the top cover 22 and the shell 21. By setting the first area 21c with a proper size, the shell 21 has sufficient structural strength and high toughness, so as to absorb and disperse the force exerted by the swelling of the bare battery cell 1 on the shell 21, reduce stress concentration at the mounting port 21b, reduce cracking at the mounting port 21b, and improve the cycle swelling life of the shell 21 under charging and discharging.

[0154] Exemplarily, in an embodiment, the first area 21c is formed on at least a preset shell wall of the shell 21, and the preset shell wall is the shell wall with the largest area of the shell 21. Here, after the bare battery cell 1 swells, since the preset shell wall is the shell wall with the largest area of the shell 21, the preset shell wall will pull the welding position between the shell 21 and the top cover 22, causing the welding position to fail, thereby causing liquid leakage. However, the first area 21c is formed on at least the preset shell wall, which can reduce the probability of liquid leakage to a certain extent.

[0155] In an embodiment, the size of the first area 21c along the first direction is not less than 1 mm.

[0156] Exemplarily, the size H3 of the first area 21c along the first direction can be 1 mm, 2 mm, 3 mm, 3 mm, 4 mm, 5 mm, 6 mm, 7 mm, 8 mm, 9 mm, 10 mm, 11 mm, or 12 mm, and the like.

[0157] In this way, by setting the first area 21c with a proper size, the cracking at the mounting port 21b can be reduced.

[0158] In an embodiment, the size of the first area 21c along the first direction is not greater than half of the size of the shell 21 along the first direction.

[0159] In this way, on the one hand, the structural strength of the shell 21 can be improved to protect the internal bare battery cell 1 and facilitate subsequent grabbing and handling; on the other hand, the toughness of the shell 21 can be improved to absorb and disperse the force exerted by the swelling of the bare battery cell 1 on the shell 21, reduce cracking, and improve the cycle swelling life of the shell 21 under charging and discharging.

[0160] In an embodiment, the opening direction of the mounting hole 21b is the first direction, and the molten pool area 21e is located on the side of the first area 21c facing the corresponding mounting hole 21b along the corresponding first direction.

[0161] That is, the molten pool area 21e is arranged between the mounting hole 21b and the first area 21c along the first direction, which facilitates stable welding of the top cover 22 and the shell 21 and improves the connection strength, and the first area 21c close to the molten pool area 21e can reduce stress concentration of the molten pool area 21e and reduce the occurrence of cracking at the molten pool area 21e.

[0162] In an embodiment, referring to FIGS. 3, 8 and 9, the first area 21c is located between the molten pool area 21e and the second area 21d along the first direction, and the first area 21c continuously extends from the molten pool area 21e to the second area 21d.

[0163] That is, the first area 21c is in contact with the second area 21d and the molten pool area 21e, respectively, and the first area 21c can be further heated and softened by the afterglow of the molten pool area 21e, so that the hardness of the first area 21c is lower and the toughness is better.

[0164] In an embodiment, referring to FIG. 5, the first area 21c includes a first sub-area 21c1 and a second sub-area 21c2, the first sub-area 21c1 is adjacent to the molten pool area 21e, and the first sub-area 21c1 and the second sub-area 21c2 are arranged apart along the first direction.

[0165] For example, the first sub-area 21c1 can be formed by heating and softening by the afterglow of the molten pool area 21e, and the second sub-area 21c2 can be formed by laser softening, and the first sub-area 21c1 and the second sub-area 21c2 are arranged apart along the first direction.

[0166] In this way, the action force exerted by the bare cell 1 can not only be absorbed and dispersed by the first sub-area 21c1, but also by the second sub-area 21c2, and the anti-cracking effect is better. The first sub-area 21c1 and the second sub-area 21c2 are arranged apart along the first direction, which means that the second sub-area 21c2 can be arranged according to the position needs to meet the needs in complex stress environment.

[0167] For example, in an embodiment, the first area 21c can be formed by heating and annealing the second area 21d.

[0168] For example, in an embodiment, the second area 21d can not need to be completely in an annealed state, as long as its hardness meets the hardness requirement of the first area 21c.

[0169] In an embodiment, referring to FIG. 5, the first sub-area 21c1 and the second sub-area 21c2 are arranged apart along the first direction by a distance of 0.05mm to 10mm.

[0170] For example, the distance between the first sub-region 21c1 and the second sub-region 21c2 along the first direction can be represented by H4, which can be 0.05 mm, 0.1 mm, 0.5 mm, 1 mm, 1.5 mm, 2 mm, 2.5 mm, 3 mm, 3.5 mm, 4 mm, 4.5 mm, 5 mm, 5.5 mm, 6 mm, 6.5 mm, 7 mm, 7.5 mm, 8 mm, 8.5 mm, 9 mm, 9.5 mm, or 10 mm, and the like.

[0171] In this way, by setting a suitable interval distance, the second sub-region 21c2 can be set as required.

[0172] In another aspect, the disclosure provides a battery 100, as shown in FIGS. 1-5, which includes a bare cell 1 and a shell 2 according to any of the above embodiments, and the bare cell 1 is arranged in the accommodating cavity 21a.

[0173] In this way, the risk of cracking of the shell 21 caused by the expansion of the bare cell 1 can be reduced, and the service life of the battery 100 can be improved.

[0174] In one embodiment, as shown in FIG. 3, the distance between the first region 21c and the bare cell 1 along the opening direction of the mounting port 21b is between 0.3 mm and 7 mm.

[0175] For example, the opening direction of the mounting port 21b is the first direction. The distance between the first region 21c and the bare cell 1 along the first direction can be represented by H5, which can be 0.3 mm, 1 mm, 2 mm, 3 mm, 4 mm, 5 mm, 6 mm, or 7 mm, and the like.

[0176] In this way, by setting a suitable interval distance, the toughness of the shell 21 can be improved, and the damage to the bare cell 1 can be reduced, and the service life of the bare cell 1 can be improved.

[0177] In one embodiment, as shown in FIG. 3, the distance between the first region 21c and the bare cell 1 along the opening direction of the mounting port 21b is between 1 mm and 3 mm.

[0178] For example, the distance H5 between the first region 21c and the bare cell 1 along the opening direction of the mounting port 21b can be 1 mm, 1.2 mm, 1.5 mm, 1.8 mm, 2 mm, 2.2 mm, 2.5 mm, 2.8 mm, or 3 mm, and the like.

[0179] In this way, by setting a suitable interval distance, the damage to the bare cell 1 can be reduced.

[0180] In an embodiment, referring to FIG. 3, the battery 100 includes a lower plastic 3 arranged on the side of the top cover 22 facing the bare battery cell 1, and the distance between the lower plastic 3 and the first area 21c in the inner-outer direction is greater than 1 mm.

[0181] For example, the distance between the lower plastic 3 and the first area 21c in the inner-outer direction can be represented as H6, and H6 can be 1 mm, 2 mm, 3 mm, 4 mm, 5 mm, 6 mm, 7 mm, 8 mm, 9 mm, or 10 mm, etc.

[0182] In this way, by arranging the lower plastic 3 on the side of the top cover 22 facing the bare battery cell 1, the insulation and separation of the top cover 22 and the bare battery cell 1 can be achieved, avoiding direct contact between the top cover 22 and the bare battery cell 1, thereby avoiding the risk of short circuit and damage to the battery 100. By arranging an appropriate spacing distance, damage to the lower plastic 3 can be reduced, and the service life of the lower plastic 3 can be improved, and the working stability is good.

[0183] For example, the inner-outer direction is perpendicular to the opening direction of the mounting port 21b, for example, it can be the second direction.

[0184] In an embodiment, the distance between the lower plastic 3 and the first area 21c in the inner-outer direction is between 1.2 mm and 5 mm.

[0185] For example, the distance between the lower plastic 3 and the first area 21c in the inner-outer direction H6 can be 1.2 mm, 1.5 mm, 2 mm, 2.5 mm, 3 mm, 3.5 mm, 4 mm, 4.5 mm, or 5 mm, etc.

[0186] In this way, by arranging an appropriate spacing distance, damage to the lower plastic 3 can be reduced.

[0187] In another aspect, the battery 100 is used in a power-using device. The power-using device can include the battery 100, and the battery 100 is used to provide power. Due to the improvement of the safety of the battery 100, the safety of the power-using device is also improved.

[0188] The power-using device is a device that uses electric energy as energy and realizes corresponding functions by consuming electric energy. For example, the power-using device can be, but is not limited to, a mobile phone, a tablet computer, a notebook computer, an electric toy, an electric tool, an electric vehicle, an electric car, a ship, a spacecraft, etc. The electric toy can include fixed or mobile electric toys, such as game consoles, electric car toys, electric ship toys, and electric plane toys, etc. The spacecraft can include airplanes, rockets, space shuttles, and spaceships, etc.

[0189] The power-using device of the embodiment of the present disclosure can include a device body and a power supply device, the power supply device is used to supply power to the device body, and the power supply device can include the battery 100.

[0190] The device body refers to a main structure that consumes electric energy to realize a corresponding function. For example, the electric device can be a mobile phone, and the device body is a part that can realize functions such as communication, and the part that can realize functions such as communication is powered by the battery 100. For example, the electric device can be a car, and the device body is a part that can accommodate people and can travel on the road, and the part that can accommodate people and can travel on the road is powered by the battery 100.

[0191] The power supply device refers to a device that can output electric energy. For example, electric energy can be output by the battery 100.

[0192] Taking a vehicle as an example, an embodiment of the present disclosure is described.

[0193] The vehicle provided by an embodiment of the present disclosure can be a fuel car, a gas car, or a new energy car, and the new energy car can be a pure electric car, a hybrid car, or an extended range car. The vehicle is internally provided with a battery 100, which can be arranged at the bottom, head, or tail of the vehicle. The battery 100 can be used for power supply of the vehicle, for example, the battery 100 can be used as an operating power supply of the vehicle. The vehicle can also include a controller and a motor, and the controller can be used to control the battery 100 to supply power to the motor. For example, the battery 100 unit can be used for the working power demand of the vehicle during starting, navigation, and driving.

[0194] In another aspect, the embodiment of the present disclosure provides a method for processing a shell, please refer to FIG. 10, the method comprises:

[0195] S1, softening: at least heating and softening a preset shell wall of the shell to soften at least part of the second area of the preset shell wall into a first area;

[0196] S2, the mounting port of the shell is in communication with the accommodating cavity of the shell, the preset shell wall is arranged adjacent to the mounting port, and the preset shell wall is the shell wall with the largest area.

[0197] For example, the second area 21d of the preset shell wall can be heated and softened by laser to be softened into the first area 21c, and the hardness of the softened first area 21c is lower than that of the second area 21d.

[0198] In this way, the preset shell wall of the shell 21 is heated and softened to soften at least the second area 21d of the preset shell wall into the first area 21c, the hardness of the first area 21c is lower than that of the second area 21d, and after the bare battery cell 1 expands, the first area 21c with lower hardness can absorb and disperse the force of the bare battery cell 1 on the preset shell wall, thereby reducing the risk of cracking of the shell 21, and in turn reducing the probability of leakage of the electrolyte in the shell 21, and improving the cycle expansion life of the shell 21 under charging and discharging. The first area 21c is softened by the second area 21d, which can reduce the addition of new materials, and the shell 21 has good integrity.

[0199] For example, in an embodiment, the second area 21d of the inner wall and / or the outer wall of the preset shell wall can be softened by laser. In this way, the addition of new materials can be reduced, and the shell 21 has good integrity.

[0200] In an embodiment, the method comprises:

[0201] S3, placing the bare battery cell into the softened shell;

[0202] S4, connecting the top cover to the shell containing the bare battery cell at the mounting port, so that the top cover blocks the bare battery cell in the accommodation cavity.

[0203] For example, the preset shell wall can be heated and softened by laser to soften part of the second area 21d into the first area 21c, then the bare battery cell 1 is placed into the accommodation cavity 21a, then the top cover 22 is covered at the mounting port 21b, and finally the shell 21 and the top cover 22 can be connected by welding to block the mounting port 21b with the top cover 22 and block the bare battery cell 1 in the accommodation cavity 21a.

[0204] In this way, the shell 21 is softened first and then connected to the top cover 22, which can reduce damage to the bare battery cell 1 when the softening operation is performed.

[0205] In an embodiment, before the softening step is performed, the method further comprises:

[0206] S5, connecting the top cover to the shell containing the bare battery cell at the mounting port, so that the top cover blocks the bare battery cell in the accommodation cavity.

[0207] For example, before the softening step is performed, the top cover 22 can be covered at the mounting port 21b, and then the shell 21 and the top cover 22 can be connected by welding to block the mounting port 21b with the top cover 22 and block the bare battery cell 1 in the accommodation cavity 21a. In this way, the position can be selected according to the softening requirement.

[0208] In an embodiment, S1, at least a preset shell wall of the shell is heated and softened to soften at least a second region of the preset shell wall into a first region, comprising:

[0209] S11, at least a target region of a preset shell wall of the shell is heated and softened to soften at least a second region of the preset shell wall into a first region, the target region is arranged between the bare battery cell and the installation port along the opening direction of the installation port, and the target region is spaced apart from the bare battery cell along the opening direction of the installation port.

[0210] For example, when softened, a target region of a preset shell wall of the shell 21 can be selected to be heated and softened to soften at least a second region 21d of the preset shell wall into a first region 21c, and the target region is arranged between the bare battery cell 1 and the installation port 21b along the first direction, and the target region is spaced apart from the bare battery cell 1 along the first direction.

[0211] In this way, by heating and softening the target region between the bare battery cell 1 and the installation port 21b into the first region 21c, and the hardness of the first region 21c is lower than the hardness of the second region 21d, when the bare battery cell 1 expands, the first region 21c can absorb and disperse the force exerted by the bare battery cell 1, reduce the stress concentration at the installation port 21b, and then reduce the risk of cracking at the installation port 21b, and improve the cycle expansion life of the shell 21 under charging and discharging.

[0212] It should be noted that the size, distance and spacing in the above embodiments can be measured by a size measurement tool on a computer software or directly by a ruler. The hardness can be measured by a metal hardness tester, for example, by dot measurement and scanning measurement. The grain type can be determined by a metallographic diagram.

[0213] It should be noted that the molten pool region 21e refers to the molten pool formed by welding the top cover 22 and the shell 21.

[0214] The shell 21 provided in the embodiment of the present disclosure, please refer to Figures 1 to 9. The shell 21 is formed with a accommodating cavity 21a and a mounting port 21b connected to the accommodating cavity 21a. The accommodating cavity 21a is used to accommodate the bare battery cell 1. The shell wall of the shell 21 is formed with a first area 21c and a second area 21d. The first area 21c is formed at least on a preset shell wall of the shell 21. The preset shell wall is the shell wall with the largest area of ​​the shell 21. The preset shell wall is arranged adjacent to the mounting port 21b. The ratio of the hardness of the first area 21c to the hardness of the second area 21d is between 0.5 and 0.8. Specifically, the material of the shell 21 is aluminum, the hardness of the second area 21d is between 35HB and 55HB, the hardness of the first area 21c is between 25HB and 45HB, the grain type of the second area 21d is strip crystal and / or ribbon crystal, and the grain type of the first area 21c is columnar crystal and / or equiaxed crystal. The first area 21c can be arranged to extend along the circumference of the mounting opening 21b, with the distance of the first area 21c on the preset shell wall along the circumference of the mounting opening 21b being no less than 50 mm; and / or, the distance of the first area 21c on the preset shell wall along the circumference of the mounting opening 21b being a first distance H1, the distance of the preset shell wall along the circumference of the mounting opening 21b being a second distance H2, and the ratio of the first distance H1 to the second distance H2 being no less than 25%. A direction perpendicular to the preset shell wall is defined as a target direction, and when projected along the target direction, the projected area of ​​the first area 21c is smaller than the projected area of ​​the second area 21d.

[0215] The above embodiments are intended only to illustrate the technical solutions of the present disclosure, and are not intended to limit them. Although the present disclosure has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they may modify the technical solutions described in the aforementioned embodiments, or replace some or all of the technical features therein with equivalents. Such modifications or replacements do not deviate from the essence of the corresponding technical solutions within the scope of the various embodiments of the present disclosure, and are intended to be encompassed by the specification of the present disclosure. In particular, the various technical features described in the various embodiments may be combined in any manner, as long as there are no structural conflicts. Industrial Applicability

[0216] The present disclosure relates to the field of battery technology and provides a housing, a battery shell, a battery, an electrical device, and a method for processing the housing. The housing has a housing cavity and a mounting opening connected to the housing cavity. The housing cavity is used to accommodate bare battery cells. The housing wall includes side walls and end walls. The first end of the side wall encloses the mounting opening. The end wall is disposed at the second end of the side wall and, together with the side wall, encloses a semi-enclosed housing cavity. The side wall has a first region and a second region, and the hardness of the first region is lower than that of the second region. The housing, battery shell, battery, electrical device, and method for processing the housing provided by the present disclosure can reduce the probability of housing cracking.

Claims

1. A shell, the shell forming a accommodating cavity and a mounting opening connected to the accommodating cavity, the accommodating cavity being used to accommodate a bare battery cell, the shell wall of the shell comprising a side wall and an end wall, the first end of the side wall being arranged to enclose the mounting opening, the end wall being arranged at the second end of the side wall and together with the side wall enclosing the semi-enclosed accommodating cavity; the side wall being formed with a first area and a second area, and the hardness of the first area being lower than the hardness of the second area.

2. The housing according to claim 1, wherein The shell wall with the largest area on the side wall is a preset shell wall, and the first area is at least formed on the preset shell wall.

3. The housing according to claim 1 or 2, wherein: The ratio of the hardness of the first region to the hardness of the second region is between 0.3 and 0.8; or the ratio of the hardness of the first region to the hardness of the second region is between 0.5 and 0.

8.

4. The housing according to any one of claims 1 to 3, wherein: The hardness of the first region and the hardness of the second region are both Brinell hardness.

5. The housing according to any one of claims 1 to 4, wherein: The shell is made of aluminum, the hardness of the second zone is between 35HB and 65HB, and the hardness of the first zone is between 25HB and 40HB.

6. The housing according to any one of claims 1 to 5, wherein: The grain type of the second region is strip-shaped crystals and / or ribbon-shaped crystals, and the grain type of the first region is columnar crystals and / or equiaxed crystals.

7. The housing according to any one of claims 1 to 6, wherein: The first area is arranged to extend along the circumference of the installation opening.

8. The housing according to claim 2, wherein The distance between the first area on the preset shell wall and the mounting opening in the circumferential direction is not less than 50 mm; and / or the distance between the first area on the preset shell wall and the mounting opening in the circumferential direction is a first distance, the distance between the preset shell wall and the mounting opening in the circumferential direction is a second distance, and the ratio of the first distance to the second distance is not less than 25%.

9. The housing according to claim 2, wherein: A direction perpendicular to the preset shell wall is a target direction. When projected along the target direction, an area of ​​a projection region of the first zone is smaller than an area of ​​a projection region of the second zone.

10. A battery housing, comprising: The housing according to any one of claims 1 to 9; A top cover is provided on the installation opening.

11. The housing according to claim 10, wherein The top cover is connected to the shell by welding, the hardness of the molten pool area formed by welding of the shell is not less than the hardness of the first area, the opening direction of the mounting port is the first direction, and the size of the first area along the first direction is not less than 0.2 mm.

12. The housing according to claim 11, wherein A dimension of the first region along the first direction is not less than 1 mm.

13. The housing according to any one of claims 11 or 12, wherein: A dimension of the first region along the first direction is no greater than half a dimension of the housing along the first direction.

14. The housing according to claim 11, wherein The opening direction of the installation opening is a first direction, and the molten pool area is located on a side of the first area corresponding to the first direction and facing the installation opening.

15. The housing according to claim 11 or 14, wherein The first zone is located between the molten pool zone and the second zone along the first direction, and the first zone extends continuously from the molten pool zone to the second zone; or, the first zone includes a first sub-zone and a second sub-zone, the first sub-zone is adjacent to the molten pool zone, and the first sub-zone and the second sub-zone are arranged at intervals along the first direction.

16. The housing according to claim 15, wherein The first sub-region and the second sub-region are spaced apart from each other by a distance in the first direction of 0.05 mm to 10 mm.

17. A battery comprising a bare cell and the housing according to any one of claims 10 to 16, wherein the bare cell is arranged in the accommodating cavity.

18. The battery according to claim 17, wherein The distance between the first area and the bare cell along the opening direction of the mounting opening is between 0.3 mm and 7 mm.

19. The battery according to claim 17 or 18, wherein The distance between the first area and the bare cell along the opening direction of the mounting opening is 1 mm to 3 mm.

20. The battery according to any one of claims 17 to 19, wherein The battery includes a lower plastic, which is arranged on a side of the top cover facing the bare cell, and a distance between the lower plastic and the first area along an inner-outer direction is greater than 1 mm.

21. The battery according to claim 20, wherein The distance between the lower plastic and the first area along the inner and outer directions is between 1.2 mm and 5 mm.

22. An electrical device comprising the battery according to any one of claims 17 to 21, for providing electrical energy.

23. A method for processing a housing, comprising: Softening: heating and softening at least a predetermined shell wall of the shell, so as to soften at least a portion of the second region of the predetermined shell wall into the first region; The installation opening of the shell is communicated with the accommodating cavity of the shell, the preset shell wall is arranged adjacent to the installation opening, and the preset shell wall is the shell wall with the largest area of ​​the shell.

24. The method according to claim 23, wherein The method further comprises: Place the bare battery cell into the softened shell; The top cover is connected to the shell containing the bare battery cell at the installation opening, so that the top cover blocks the bare battery cell in the accommodating cavity.

25. The method according to claim 23, wherein Before performing the softening step, the method further comprises: The top cover is connected to the shell containing the bare battery cell at the installation opening, so that the top cover blocks the bare battery cell in the accommodating cavity.

26. The method according to claim 25, wherein Heating and softening at least a predetermined shell wall of the shell to soften at least a portion of the second region of the predetermined shell wall into the first region comprises: At least a target area of ​​a preset shell wall of the shell is heated and softened to soften at least a portion of the second area of ​​the preset shell wall into a first area, the target area is located between the bare battery cell and the mounting port along the opening direction of the mounting port, and the target area and the bare battery cell are spaced apart from each other along the opening direction of the mounting port.

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