Square battery and electric device using the same

Abstract

The application provides a square battery and an electric device, which comprises: an electric core; a shell, which is provided with an opening, the electric core is arranged in the shell, and an inner surface of the shell is provided with at least one inner recess, the inner recess is arranged at least in the inner surface of a side with a relatively large area of the shell; and a cover plate, which is connected with the shell and closes the opening. The square battery provided by the application can reduce the weight of the shell, reduce the deformation of the shell, and improve the safety of the electric core.

Description

Technical Field

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

[0002] Existing square battery casings are usually made of metal materials to improve the strength of the battery casing, such as aluminum alloy. However, metal materials are heavy and it is difficult to meet the requirements of lightweight and mechanical strength of the battery casing at the same time. For example, when the casing is too thin, the mechanical strength will be reduced. Especially when the cell expands or is squeezed by the outside, the thin casing is prone to stress concentration, which will cause the casing to deform and bulge, increasing the safety risk of the battery. Utility Model Content

[0003] In order to overcome the defects in the prior art, this utility model provides a square battery and power device that can reduce the weight of the casing and reduce casing deformation, thereby improving the safety of the battery cell.

[0004] To achieve the above objectives, the technical solution adopted by this utility model is as follows:

[0005] The first aspect of this utility model discloses a square battery, comprising:

[0006] Battery cell;

[0007] The housing has an opening, the battery cell is disposed inside the housing, and the inner surface of the housing has at least one recess, the recess being located on at least one inner surface of the housing with a relatively larger area.

[0008] A cover plate, which is connected to the housing and closes the opening.

[0009] The above technical solution reduces the weight of the casing and increases the energy density of the battery cell by setting a concave part on the inner surface of the casing. The cavity formed by the concave part absorbs the expansion energy, which reduces the weight of the casing and improves the deformation resistance of the casing surface, reduces the deformation and bulging of the casing after charging and discharging, and improves the safety of the battery cell.

[0010] Furthermore, the recessed portion is polygonal.

[0011] Furthermore, the recessed portion is a regular hexagon, and the recessed portions are arranged in an array along the inner surface of the shell to form a honeycomb structure. The honeycomb hexagonal structure has high symmetry and can be uniformly arranged on the inner surface of the shell, which maximizes the space utilization of the shell surface compared to other polygons.

[0012] Furthermore, the distance between the two parallel sides of any two adjacent concave portions is 0.2 to 0.3 times the thickness of the non-concave region of the shell. If the distance between the parallel sides of any two adjacent concave portions is too large, the concave portions will be too small and unable to effectively absorb expansion energy. If the distance between the parallel sides of any two adjacent concave portions is too small, it will easily lead to buckling of the concave portion wall, reducing the shell's resistance to deformation. At the same time, the elastic modulus of the shell will decrease, resulting in uneven stress distribution on the shell surface.

[0013] Furthermore, the distance between the two adjacent parallel edges of any two adjacent recesses is 0.25 times the thickness of the non-recessed region of the shell.

[0014] Furthermore, the depth of the recess is 0.3 to 0.5 times the thickness of the non-recessed area of ​​the shell. If the recess is too deep, the bottom of the recess will be too thin, reducing the shell's impact resistance; if the recess is too shallow, it will reduce the stress dispersion effect on the shell surface, causing the shell to expand and deform.

[0015] Furthermore, the depth of the recess is 0.4 times the thickness of the non-recessed area of ​​the shell.

[0016] Furthermore, the concave portion is configured such that its inscribed circle has a diameter of 3–10 mm. If the diameter of the inscribed circle is too large, the concave portion will be too large, which will reduce the density ratio and equivalent stiffness of the honeycomb structure, resulting in a decrease in the compressive strength of the shell. If the diameter is too small, the concave portion will be too small, which will not be able to effectively absorb expansion energy, resulting in a decrease in the deformation resistance of the shell surface.

[0017] Furthermore, the shell is integrally formed.

[0018] The second aspect of this utility model discloses an electrical device, which includes a square battery as described in any one of the first aspects.

[0019] Due to the application of the above technical solution, this utility model has the following advantages compared with the prior art:

[0020] This application reduces the weight of the casing and increases the energy density of the battery cell by providing a recess on the inner surface of the casing. The cavity formed by the recess absorbs the expansion energy, which reduces the weight of the casing and improves the deformation resistance of the casing surface, reduces the deformation and bulging of the casing after charging and discharging, and improves the safety of the battery cell.

[0021] To make the above and other objects, features and advantages of this utility model more apparent and understandable, preferred embodiments are described below in detail with reference to the accompanying drawings. Attached Figure Description

[0022] To more clearly illustrate the technical solutions in the embodiments of this utility model or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this utility model. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0023] Figure 1 This is a shell structure diagram provided in an embodiment of this application;

[0024] Figure 2 This is a partial top view of a housing provided in an embodiment of this application;

[0025] Figure 3 This is a partial honeycomb structure diagram of a shell provided in an embodiment of this application;

[0026] Figure 4 This is a schematic diagram of a recess provided in an embodiment of this application;

[0027] Figure 5 This is a structural diagram of a square battery provided in an embodiment of this application.

[0028] The reference numerals in the above figures are as follows: 1. Housing; 101. First side; 102. Second side; 103. Bottom; 2. Recess; 3. Cover plate. Detailed Implementation

[0029] The technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. In addition, the accompanying drawings of the present invention are only simple schematic illustrations and are not depictions based on actual dimensions, as stated in advance.

[0030] In this utility model, it should be noted that the terms "upper," "lower," "inner," "outer," "forward," "backward," "between," "nearer," and "farthest" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. These terms are used only for the convenience of describing this utility model and for 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. It should also be noted that, unless otherwise explicitly specified and limited, the terms "installation" and "connection" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a direct connection or an indirect connection. Those skilled in the art can understand the specific meaning of the above terms in this utility model according to the specific circumstances.

[0031] It should be understood that while terms such as "first," "second," and "third" may be used in this document to describe various components or signals, these components or signals should not be limited by these terms. These terms are primarily used to distinguish one component from another, or one signal from another. Furthermore, the term "or" as used herein should, as appropriate, include any combination of one or more of the related listed items.

[0032] Reference Figures 1-5 This application provides a square battery, including a cell, a casing 1 and a cover plate 3. The casing 1 has an opening, the cell is disposed inside the casing 1, and the cover plate 3 is connected to the casing 1 to close the opening. The casing 1 has at least one recess 2 on its inner surface opposite to the cell, and the at least one recess 2 is disposed on the inner side of the relatively large surface of the casing 1.

[0033] The recess 2 has a certain depth, and the shell thickness at the bottom of the recess 2 is thinner than the shell thickness in the area without the recess. Since the shell 1 has multiple recesses 2 formed according to preset conditions, the shell 1 can reduce the weight while reducing the deformation and bulging during the charging and discharging process of the battery cell, thereby improving the safety of the battery cell and enabling the battery to meet the requirements of both lightweight and high strength.

[0034] Specifically, the housing 1 is made of metal material, and an inner recess 2 is formed from the inner surface of the metal material. In one possible embodiment, the housing 1 is integrally formed from an aluminum plate by stamping and stretching. The inner recess 2 on the aluminum plate can be formed by stamping a smooth aluminum plate with a mold.

[0035] like Figure 1 and Figure 2 As shown, the housing 1 includes a first side 101, a second side 102 and a bottom surface 103, wherein two opposing first side 101 and two opposing second side 102 surround the periphery of the bottom surface 103 to form the housing 1. At least one recess 2 may be provided only on the first side 101, or the recess 2 may be provided on both the first side 101 and the second side 102.

[0036] It should be noted that the first side 101 is a relatively large surface area on the housing 1, and is only used to illustrate the setting position of the recess 2, not to limit the side position of the housing 1.

[0037] The shape and number of the recesses 2 can be flexibly set, such as circular, elliptical, triangular, regular polygonal, irregular polygonal, or irregular shapes. The recesses 2 can be evenly or unevenly distributed, and the size and shape of the recesses 2 can be arbitrarily combined as needed.

[0038] In one possible embodiment, the recess 2 is a regular hexagon, and the recess 2 is arranged in an array along the inner surface of the shell 1 to form a honeycomb structure. The honeycomb structure can uniformly distribute stress and reduce the deformation of the shell 1.

[0039] In some embodiments, any two adjacent regular hexagons have two opposing parallel sides, and the distance between the two parallel sides is 0.2 to 0.3 times the thickness of the non-recessed region of the shell, thereby helping to increase the equivalent elastic modulus of the shell 1. For example... Figure 4 As shown, the distance between the two parallel sides of any two adjacent concave portions 2 is A. The equivalent elastic modulus is the macroscopic elastic response caused by the composition and geometry of the composite material, used to describe the overall elastic behavior of the composite material.

[0040] In one possible embodiment, the distance between the two parallel sides of any two adjacent regular hexagons is 0.25 times the thickness of the non-recessed region of the shell.

[0041] In some embodiments, in order to improve the impact resistance and stress dispersion effect of the housing 1, the depth of the recess 2 is 0.3 to 0.5 times the thickness of the non-recessed area of ​​the housing 1.

[0042] In one possible embodiment, the depth of the recess 2 is 0.4 times the thickness of the non-recessed area of ​​the housing 1.

[0043] In some embodiments, the dimensions of the recess 2 are configured such that the diameter of the inscribed circle of the recess 2 is 3–10 mm, thereby improving the deformation resistance of the shell 1 while avoiding a reduction in the density ratio and equivalent stiffness of the honeycomb core. The density ratio refers to the ratio of the recessed region to the distance between any two adjacent recesses. Equivalent stiffness is an indicator of the stiffness of a structure or system, typically measured in elastic modulus.

[0044] The deformation resistance of the square battery in this application is illustrated below with reference to specific embodiments:

[0045] Example 1:

[0046] Process the battery casing according to the following parameters:

[0047] Casing material: 3003-H14 aluminum alloy

[0048] A hexagonal recess is provided on the inner surface of the shell, which has a relatively large area. The shell thickness is 0.6 mm.

[0049] Number of recesses (cell density) ≈ 1200 / ㎡

[0050] Concave shape: regular hexagon

[0051] The diameter of the inscribed circle of the concave part is 5mm.

[0052] The distance between the two parallel sides of any two adjacent concave portions (value A) is 0.1 mm.

[0053] Depth of inner recess: 0.24mm

[0054] Internal pressure of the battery cell (P): 0.5 MPa.

[0055] Example 2:

[0056] Process the battery casing according to the following parameters:

[0057] Casing material: 3003-H14 aluminum alloy

[0058] A hexagonal recess is provided on the inner surface of the shell, which has a relatively large area. The shell thickness is 0.6 mm.

[0059] Number of recesses (cell density) ≈ 1200 / ㎡

[0060] Concave shape: Regular hexagonal concave part with an inscribed circle diameter of 5mm.

[0061] The distance between the two parallel sides of any two adjacent concave portions (value A) is 0.15 mm.

[0062] Depth of inner recess: 0.24mm

[0063] Internal pressure of the battery cell (P): 0.5 MPa.

[0064] Example 3:

[0065] Process the battery casing according to the following parameters:

[0066] Casing material: 3003-H14 aluminum alloy

[0067] A hexagonal recess is provided on the inner surface of the shell, which has a relatively large area. The shell thickness is 0.6 mm.

[0068] Number of recesses (cell density) ≈ 1200 / ㎡

[0069] Concave shape: Regular hexagonal concave part with an inscribed circle diameter of 20mm.

[0070] The distance between the two parallel sides of any two adjacent concave portions (value A) is 0.1 mm.

[0071] Depth of inner recess: 0.24mm

[0072] Internal pressure of the battery cell (P): 0.5 MPa.

[0073] Comparative example:

[0074] Process the battery casing according to the following parameters:

[0075] Casing material: 3003-H14 aluminum alloy

[0076] The housing has no recessed portion; housing thickness: 0.6mm.

[0077] Internal pressure of the battery cell (P): 0.5 MPa.

[0078] Stress and deformation tests were performed on the batteries fabricated in the above embodiments and comparative examples, and the results are shown in Table 1.

[0079] Table 1

[0080] Maximum stress (MPa) 127 180 250 280 Maximum deformation (mm) 0.48 1.5 5 1.2 Maximum safety factor 2.3 1.25 0.89 1.04 Buckling critical pressure (MPa) 1.4 5.04 0.14 0.6

[0081] As can be seen from Table 1, when the concave portion configured according to the parameters of the embodiments of this application, i.e., the distance between the two parallel sides of the regular hexagonal concave portion is in the range of 0.2 to 0.3 times the thickness of the shell 1, and the diameter of the inscribed circle of the concave portion is in the range of 3 to 10 mm, compared with the battery shell without concave portion, and when the distance between the two parallel sides of the concave portion exceeds the range of the embodiments of this application and the diameter of the inscribed circle of the concave portion exceeds the range of the embodiments of this application, the stress and deformation risk on the shell surface can be significantly reduced, and the safety factor and buckling critical pressure can be significantly improved.

[0082] Among them, the buckling critical pressure refers to the axial pressure value that a member can withstand when it changes from a stable equilibrium state to an unstable equilibrium state under the action of axial pressure in the mechanics of materials.

[0083] This application also provides an electrical device, which includes a square battery as described in the above embodiments.

[0084] This utility model uses specific embodiments to illustrate the principle and implementation of the utility model. The above description of the embodiments is only for the purpose of helping to understand the method and core idea of ​​the utility model. At the same time, for those skilled in the art, there will be changes in the specific implementation and application scope based on the idea of ​​the utility model. Therefore, the content of this specification should not be construed as a limitation of the utility model.

Claims

1. A square battery, characterized by, include: Battery cell; The housing has an opening, the battery cell is disposed inside the housing, and the inner surface of the housing has at least one recess, the recess being located on at least one inner surface of the housing with a relatively larger area. A cover plate, which is connected to the housing and closes the opening.

2. The prismatic battery of claim 1, wherein, The concave portion is polygonal.

3. A square battery according to claim 2, wherein The recessed portion is a regular hexagon, and the recessed portion is arranged in an array along the inner surface of the shell to form a honeycomb structure.

4. A square battery according to claim 3, wherein The distance between the two adjacent parallel sides of any two adjacent concave portions is 0.2 to 0.3 times the thickness of the non-concave region of the shell.

5. A square battery according to claim 4, wherein The distance between the two adjacent parallel sides of any two adjacent recesses is 0.25 times the thickness of the non-recessed area of ​​the shell.

6. The square battery of claim 1, wherein, The depth of the recess is 0.3 to 0.5 times the thickness of the non-recessed area of ​​the shell.

7. A square battery according to claim 6, wherein The depth of the recess is 0.4 times the thickness of the non-recessed area of ​​the shell.

8. The square battery of claim 1, wherein, The concave portion is configured such that the inscribed circle of the concave portion has a diameter of 3 to 10 mm.

9. The square battery of claim 1, wherein, The shell is integrally molded.

10. An electrical device, characterized by The electrical device includes a square battery as described in any one of claims 1 to 9.

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