A square aluminum shell lithium battery shell and a square aluminum shell lithium battery

Abstract

The utility model discloses a square aluminium shell lithium cell shell and square aluminium shell lithium cell, including aluminium shell, be square shell structure, the top of aluminium shell is equipped with the installation opening, and the opposite side wall of at least a pair of aluminium shell is equipped with a plurality of reinforcing ribs respectively, and the reinforcing rib sets up from the inside of aluminium shell to the outside convex, and a plurality of reinforcing ribs arrange and set along the depth direction of aluminium shell, and the reinforcing rib extends along the circumference of aluminium shell side wall, and the inboard wall of aluminium shell is equipped with the recess in the position corresponding to a plurality of reinforcing ribs, and aluminium shell and reinforcing rib integrative forming set up. Improve the section inertia moment of aluminium shell side wall and disperse pressure stress load, greatly reduce the degree of shell deformation, need not increase the wall thickness and weight of aluminium shell, can have certain bending -resistant capacity, and guarantee the internal space of aluminium shell, reduce the damage risk to electrode assembly, and then reinforcing rib can improve the side surface structural strength of aluminium shell, and prevent the shell from deforming due to negative pressure air exhaust.

Description

Technical Field

[0001] This utility model relates to the field of lithium battery technology, and in particular to a square aluminum-cased lithium battery casing and a square aluminum-cased lithium battery. Background Technology

[0002] In the formation process of square aluminum-cased lithium batteries, it is necessary to use negative pressure evacuation to remove gas and promote electrolyte wetting, and to extract the generated gas to ensure interface adhesion. Currently, the industry generally uses the electrolyte injection port at the top of the battery for evacuation. However, the sides of square aluminum casings are usually flat and thin-walled structures (thickness is usually 0.3mm to 0.8mm). Under the high vacuum inside (such as -90kPa), the external atmospheric pressure will exert a huge inward pressure. When this pressure exceeds the yield strength of the aluminum casing material, it will cause irreversible plastic concave deformation of the sidewalls, affecting product performance and production yield. Utility Model Content The purpose of this utility model is to provide a square aluminum-cased lithium battery casing and a square aluminum-cased lithium battery to solve one or more technical problems existing in the prior art, and at least provide a beneficial option or create conditions.

[0003] The technical solution adopted to solve the above-mentioned technical problems is as follows: This utility model provides a square aluminum-cased lithium battery casing, comprising: The aluminum shell has a square shell structure. The top of the aluminum shell has an installation opening. At least one pair of opposing sidewalls of the aluminum shell are provided with multiple reinforcing ribs. The reinforcing ribs protrude from the inside of the aluminum shell to the outside. The multiple reinforcing ribs are arranged along the depth direction of the aluminum shell. The reinforcing ribs extend circumferentially along the sidewalls of the aluminum shell. The inner sidewall of the aluminum shell has grooves at positions corresponding to the multiple reinforcing ribs. The aluminum shell and the reinforcing ribs are integrally formed.

[0004] The beneficial effects of this square aluminum-cased lithium battery casing are as follows: By integrally forming multiple reinforcing ribs on the opposing sidewalls of the aluminum casing, the moment of inertia of the aluminum casing sidewall section is increased (bending stiffness is increased by 280%) and the compressive stress load is dispersed, raising the critical buckling negative pressure from -70kPa to -98kPa, which greatly reduces the degree of casing deformation. Furthermore, the reinforcing ribs are arranged to protrude from the inside to the outside of the aluminum casing, and the inner sidewall of the aluminum casing has grooves at the positions corresponding to the reinforcing ribs. This allows for a certain degree of bending resistance without increasing the wall thickness and weight of the aluminum casing, while ensuring the internal space of the aluminum casing and reducing the risk of damage to the electrode components. In addition, the reinforcing ribs can enhance the side structural strength of the aluminum casing and prevent casing deformation caused by negative pressure suction.

[0005] As a further improvement to the above technical solution, the groove is pre-embedded with an aluminum nitride ceramic sheet.

[0006] As a further improvement to the above technical solution, the surface of the groove is provided with a sandblasting layer.

[0007] As a further improvement to the above technical solution, the protrusion height of the reinforcing rib is 0.2-0.4 times the sidewall thickness of the aluminum shell.

[0008] As a further improvement to the above technical solution, the cross-section of the reinforcing rib is an arc-shaped structure or a trapezoidal structure.

[0009] As a further improvement to the above technical solution, the spacing between two adjacent reinforcing ribs is 30-50 times the protrusion height of the reinforcing rib.

[0010] As a further improvement to the above technical solution, on the top-view projection surface, the aluminum shell is provided with two long sidewalls and two short sidewalls, the length of the long sidewalls is greater than the length of the short sidewalls, and the reinforcing ribs are provided on the two long sidewalls.

[0011] As a further improvement to the above technical solution, the reinforcing rib is a wavy continuous rib structure.

[0012] As a further improvement to the above technical solution, the aluminum shell and the reinforcing rib are integrally formed and stamped.

[0013] In addition, this utility model also proposes a square aluminum-cased lithium battery, including the square aluminum-cased lithium battery casing, and further including an electrode assembly and a top cover. The electrode assembly is disposed inside the aluminum casing, and the top cover seals the mounting opening.

[0014] Other features and advantages of this invention will be set forth in the description which follows, and will be apparent in part from the description, or may be learned by practicing the invention. Attached Figure Description

[0015] The present invention will be further described below with reference to the accompanying drawings and embodiments; Figure 1 This is a schematic diagram of an embodiment of the square aluminum-shell lithium battery casing provided by this utility model, in which reinforcing ribs are provided on the two long side walls. Figure 2 yes Figure 5 A magnified view of part A in the middle; Figure 3 This is a schematic diagram of an embodiment of the square aluminum-shell lithium battery casing provided by this utility model, in which reinforcing ribs are provided on the two short side walls; Figure 4 This is a schematic diagram of an embodiment of the square aluminum-shell lithium battery casing provided by this utility model, in which reinforcing ribs are provided on two short side walls and two long side walls. Figure 5 This is a cross-sectional view of an embodiment of the square aluminum-cased lithium battery casing provided by this utility model; Icon labels: Aluminum housing 100; mounting opening 110; reinforcing rib 120; groove 130; long side wall 140; short side wall 150. Detailed Implementation

[0016] The embodiments of this utility model are described in detail below. Examples of these embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain this utility model, and should not be construed as limiting this utility model.

[0017] In the description of this utility model, it should be understood that the orientation descriptions, such as up, down, etc., are based on the orientation or positional relationship shown in the drawings. They are only for the convenience of describing this utility model and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this utility model.

[0018] In the description of this utility model, "multiple" refers to two or more. The use of "first" and "second" is for distinguishing technical features only and should not be construed as indicating or implying relative importance, or implicitly indicating the number of technical features or their sequential relationship.

[0019] In the description of this utility model, unless otherwise explicitly defined, terms such as "setting," "installation," and "connection" should be interpreted broadly, and those skilled in the art can reasonably determine the specific meaning of the above terms in this utility model in conjunction with the specific content of the technical solution.

[0020] The technical solution of this utility model will be clearly and completely described below with reference to the accompanying drawings. Obviously, the embodiments described below are some embodiments of this utility model, not all embodiments.

[0021] Existing square aluminum shells typically have flat, thin-walled sides with a thickness of 0.3mm to 0.8mm. Under high internal vacuum conditions, such as -90kPa, external atmospheric pressure exerts enormous inward pressure. When this pressure exceeds the yield strength of the aluminum shell material, it causes irreversible plastic concave deformation of the sidewalls, affecting product performance and production yield.

[0022] The current solutions to this problem in the industry have obvious shortcomings: 1. Optimize pumping parameters, such as reducing vacuum level / rate: the effect is limited, and it prolongs the process time, affecting efficiency.

[0023] 2. Change the extraction location / method, such as applying it from the fixture: This requires modifying the existing formation equipment, increasing costs.

[0024] 3. Add external reinforcement structures or thicken the casing: This increases battery weight and cost, goes against the trend of lightweighting, and thickening the casing has a negative impact on space utilization.

[0025] 4. External reinforcing rib 120: Affects battery appearance and module integration, and may increase pack size.

[0026] Therefore, there is an urgent need for a square aluminum-cased lithium battery casing that can effectively resist negative pressure deformation without significantly increasing cost and weight, and without affecting the battery's appearance, size, and module integration.

[0027] like Figures 1 to 5 As shown, the square aluminum-cased lithium battery casing of this utility model includes an aluminum casing 100.

[0028] like Figure 1 As shown, the aluminum housing 100 has a square shell structure. The top of the aluminum housing 100 is provided with an upward-facing mounting opening 110 for mounting a top cover. The top cover and the interior of the aluminum housing 100 form a receiving cavity for accommodating the mounting electrode assembly.

[0029] In this invention, at least one pair of opposing sidewalls of the aluminum shell 100 are provided with a plurality of reinforcing ribs 120. The reinforcing ribs 120 protrude from the inside of the aluminum shell 100 to the outside. The plurality of reinforcing ribs 120 are arranged along the depth direction of the aluminum shell 100 and extend circumferentially along the sidewall of the aluminum shell 100. It can be understood that the plurality of reinforcing ribs 120 are arranged along the vertical direction.

[0030] Among them, such as Figure 2 As shown, the inner sidewall of the aluminum shell 100 is provided with a groove 130 corresponding to the position of the reinforcing rib 120. The aluminum shell 100 and the reinforcing rib 120 are integrally formed. It can be understood that the reinforcing rib 120 is formed by protruding from the inside to the outside of the sidewall of the aluminum shell 100. In the manufacturing process, the aluminum shell 100 and the reinforcing rib 120 are integrally formed and stamped in this embodiment. For example, this embodiment adopts a two-stage precision stamping process: First stamping: forming a standard shell blank with a smooth inner wall; Second stamping: the die rigidly supports the outer surface of the shell, and the punch accurately presses the rib shape from the inside, with a stroke control accuracy of ±0.02mm, ensuring zero deformation of the outer surface.

[0031] In some other embodiments, the manufacturing process is replaced by: a single compound stamping, in which a movable insert is pre-placed in the stretching die to simultaneously complete the shell forming and rib pressing; and hydroforming: the shell is placed in a high-pressure hydraulic chamber and the ribs are extruded by hydraulic pressure, which is suitable for ultra-thin shells with a wall thickness of <0.4mm.

[0032] This invention improves the moment of inertia and distributes compressive stress load of the aluminum shell 100 by integrally forming multiple reinforcing ribs 120 on the opposing sidewalls of the aluminum shell 100, thereby increasing the critical buckling negative pressure from -70kPa to -98kPa and significantly reducing the degree of shell deformation. Furthermore, the reinforcing ribs 120 protrude from the inside to the outside of the aluminum shell 100, and the inner sidewall of the aluminum shell 100 has grooves 130 at positions corresponding to the reinforcing ribs 120. This provides a certain degree of bending resistance without increasing the wall thickness and weight of the aluminum shell 100, while ensuring the internal space of the aluminum shell 100 and reducing the risk of damage to the electrode assembly. In addition, the reinforcing ribs 120 can enhance the side structural strength of the aluminum shell 100 and prevent shell deformation caused by negative pressure suction.

[0033] In some embodiments, an aluminum nitride ceramic sheet is pre-embedded in the groove 130, and the thickness of the aluminum nitride ceramic sheet is 0.2 mm, which reduces the thermal resistance of the housing by 15% to 18%.

[0034] In some embodiments, the surface of the groove 130 is provided with a sandblasting layer, and the surface of the groove 130 is micro-sandblasted to enhance the spreadability of the electrolyte.

[0035] In some embodiments, the protrusion height of the reinforcing rib 120 is 0.2-0.4 times the sidewall thickness of the aluminum shell 100, ensuring a certain bending resistance and guaranteeing the internal space of the core.

[0036] In some embodiments, the cross-section of the reinforcing rib 120 is an arc-shaped or trapezoidal structure to reduce the risk of damage to the electrode assembly.

[0037] In some embodiments, the spacing between two adjacent reinforcing ribs 120 is 30-50 times the height of the protrusion of the reinforcing rib 120 to avoid stress concentration and stamping cracks.

[0038] In some embodiments, such as Figure 1 , Figure 3 , Figure 4 As shown, on the top-view projection plane, the aluminum shell 100 has two long sidewalls 140 and two short sidewalls 150, the length of the long sidewalls 140 is greater than the length of the short sidewalls 150, as... Figure 1 As shown, the reinforcing ribs 120 are provided on the two long sidewalls 140.

[0039] In some other embodiments, such as Figure 3 As shown, the reinforcing ribs 120 are provided on the two short sidewalls 150, as... Figure 4 As shown, or reinforcing ribs 120 are provided on both long sidewalls 140 and both short sidewalls 150.

[0040] In some embodiments, the stiffener 120 is a wavy continuous stiffener structure.

[0041] The technical advantages of the square aluminum-shell lithium battery casing of this utility model are as follows: Deformation resistance: In the -92kPa / 5min test, the plastic deformation of the conventional shell is 0.52mm, while the shell of this application is ≤0.08mm, a reduction of 85%; Lightweight advantages: When achieving the same resistance to deformation, it saves 18% to 30% of aluminum compared to the overall thickening solution; Compatibility: External dimensions conform to GB / T 33341-2016 standard, and no design adjustments are required for module integration.

[0042] In addition, this utility model also proposes a square aluminum-cased lithium battery, including the above-mentioned square aluminum-cased lithium battery casing, as well as an electrode assembly and a top cover. The electrode assembly is disposed inside the aluminum casing 100, and the top cover seals the mounting opening 110.

[0043] In the description of this specification, the references to terms such as "one embodiment," "some embodiments," "illustrative embodiment," "example," "specific example," or "some examples," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of the present invention. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples.

[0044] The embodiments of the present utility model have been described in detail above with reference to the accompanying drawings. However, the present utility model is not limited to the above embodiments. Within the scope of knowledge possessed by those skilled in the art, various changes can be made without departing from the spirit of the present utility model.

Claims

1. A square aluminum-cased lithium battery casing, characterized in that, include: The aluminum shell has a square shell structure. The top of the aluminum shell has an installation opening. At least one pair of opposing sidewalls of the aluminum shell are provided with multiple reinforcing ribs. The reinforcing ribs protrude from the inside of the aluminum shell to the outside. The multiple reinforcing ribs are arranged along the depth direction of the aluminum shell. The reinforcing ribs extend circumferentially along the sidewalls of the aluminum shell. The inner sidewall of the aluminum shell has grooves at positions corresponding to the multiple reinforcing ribs. The aluminum shell and the reinforcing ribs are integrally formed.

2. The square aluminum-cased lithium battery casing according to claim 1, characterized in that: The groove is pre-embedded with aluminum nitride ceramic sheets.

3. The square aluminum-cased lithium battery casing according to claim 1, characterized in that: The surface of the groove is provided with a sandblasted layer.

4. The square aluminum-cased lithium battery casing according to claim 1, characterized in that: The height of the reinforcing rib is 0.2-0.4 times the thickness of the sidewall of the aluminum shell.

5. The square aluminum-cased lithium battery casing according to claim 1, characterized in that: The cross-section of the reinforcing rib is an arc-shaped structure or a trapezoidal structure.

6. The square aluminum-cased lithium battery casing according to claim 1, characterized in that: The spacing between two adjacent reinforcing ribs is 30-50 times the height of the protrusion of the reinforcing rib.

7. The square aluminum-cased lithium battery casing according to claim 1, characterized in that: On the top-view projection surface, the aluminum shell has two long sidewalls and two short sidewalls, the length of the long sidewalls is greater than the length of the short sidewalls, and the reinforcing ribs are provided on the two long sidewalls.

8. The square aluminum-cased lithium battery casing according to claim 1, characterized in that: The reinforcing rib is a wavy continuous rib structure.

9. The square aluminum-cased lithium battery casing according to claim 1, characterized in that: The aluminum shell and the reinforcing rib are integrally formed and stamped.

10. A square aluminum-cased lithium battery, characterized in that: The battery includes a square aluminum-cased lithium battery housing as described in any one of claims 1 to 9, and further includes an electrode assembly and a top cover, wherein the electrode assembly is disposed within the aluminum housing and the top cover covers the mounting opening.

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