Battery case, battery cell, and battery device

Abstract

The utility model discloses a battery housing, battery monomer and battery device, battery housing includes: shell body and insulating coating, insulating coating is located at the surface of shell body, and the thickness T of insulating coating meets with the roughness Rz of the surface of shell body, T=a*Rz, wherein, a >=1.1. According to the battery housing of the utility model, the thickness of insulating coating is controlled in the range of not less than 1.1 times roughness, can control the thickness of insulating coating according to the roughness of the surface of shell body, makes insulating coating can completely cover uneven peak and valley on the surface of shell body, and can guarantee having certain covering thickness margin, thereby can avoid uneven peak and valley on the surface of shell body and leak out and lead to insulation failure, and further can improve the safety performance of battery housing.

Description

Technical Field

[0001] This utility model relates to the field of battery technology, and in particular to a battery casing, a battery cell, and a battery device. Background Technology

[0002] With the continuous development of the new energy industry, the application fields of batteries are also increasing. To prevent short circuits between multiple batteries during use, insulation structures are typically installed on the battery casing. However, the insulation structures in these technologies have a high risk of failure. If the insulation structure fails, short circuits between multiple batteries can easily lead to fires or explosions, directly affecting the safety of battery use. Utility Model Content

[0003] The first aspect of this utility model proposes a battery casing, which has the advantage of high safety performance.

[0004] A battery casing according to a first aspect of the present invention includes: a casing body; an insulating coating disposed on the surface of the casing body, wherein the thickness T of the insulating coating and the surface roughness Rz of the casing body satisfy T=a*Rz, where a≥1.1.

[0005] According to the battery casing of the first aspect of the present invention, the thickness of the insulating coating is controlled within a range of not less than 1.1 times the roughness. The thickness of the insulating coating can be controlled according to the surface roughness of the casing body, so that the insulating coating can completely cover the uneven peaks and valleys on the surface of the casing body and ensure that there is a certain coverage thickness margin. This can avoid insulation failure caused by leakage of uneven peaks and valleys on the surface of the casing body, thereby improving the safety performance of the battery casing.

[0006] According to some embodiments of this utility model, a ≥ 5; and / or, a ≤ 25.

[0007] According to some embodiments of this utility model, the thickness T of the insulating coating ranges from 0.88μm to 100μm.

[0008] According to some embodiments of this utility model, the thickness T of the insulating coating ranges from 5μm to 80μm.

[0009] According to some embodiments of this utility model, the thickness T of the insulating coating satisfies: T≥R*A / ρ, where R is the resistivity requirement of the insulating coating, A is the coverage area of ​​the insulating coating on the surface of the housing body, ρ is the conductivity of the insulating coating; and / or, the value range of Rz is 0.8μm-10μm.

[0010] According to some embodiments of the present invention, the insulating coating is disposed on the outer surface of the housing body; and / or, the battery housing is cylindrical, and the insulating coating at least covers the outer peripheral surface of the housing body.

[0011] According to some embodiments of the present invention, edge edges are formed between different sides of the housing body, and the insulating coating covers at least a portion of the edge edges.

[0012] According to some embodiments of the present invention, the housing body is one of a steel shell, an aluminum shell, or a titanium shell; and / or, the insulating coating includes one of an epoxy resin layer, a polyurethane resin layer, or an organosilicon layer.

[0013] The second aspect of this utility model proposes a battery cell.

[0014] A battery cell according to a second aspect of the present invention includes: the battery housing described above; and an electrode assembly disposed within the battery housing.

[0015] According to the second aspect of the present invention, the thickness of the insulating coating in the battery cell is controlled within a range of not less than 1.1 times the roughness. The thickness of the insulating coating can be controlled according to the surface roughness of the casing body, so that the insulating coating can completely cover the uneven peaks and valleys on the surface of the casing body and ensure that there is a certain coverage thickness margin. This can avoid insulation failure caused by leakage of uneven peaks and valleys on the surface of the casing body, thereby improving the safety performance of the battery casing.

[0016] The third aspect of this utility model proposes a battery device.

[0017] The battery device according to a third aspect of the present invention includes: the aforementioned battery cell.

[0018] According to the battery device of the third aspect of the present invention, the thickness of the insulating coating is controlled within a range of not less than 1.1 times the roughness. The thickness of the insulating coating can be controlled according to the surface roughness of the housing body, so that the insulating coating can completely cover the uneven peaks and valleys on the surface of the housing body and ensure that there is a certain coverage thickness margin. This can avoid insulation failure caused by leakage of uneven peaks and valleys on the surface of the housing body, thereby improving the safety performance of the battery housing.

[0019] Additional aspects and advantages of this invention will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention. Attached Figure Description

[0020] Figure 1 This is a schematic diagram of a battery casing according to an embodiment of the present utility model; Figure 2 This is a partial cross-sectional view of the battery casing according to an embodiment of the present utility model.

[0021] Figure label: 100. Battery cell; 10. Battery casing; 1. Casing body; 2. Insulating coating; 20. Electrode assembly. Detailed Implementation

[0022] 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 intended to explain this utility model, and should not be construed as limiting this utility model.

[0023] The following disclosure provides numerous different embodiments or examples for implementing various structures of the present invention. To simplify the disclosure, specific examples of components and arrangements are described below. These are merely examples and are not intended to limit the scope of the invention. Furthermore, reference numerals and / or letters may be repeated in different examples. Such repetition is for simplification and clarity and does not in itself indicate a relationship between the various embodiments and / or arrangements discussed. In addition, examples of various specific processes and materials are provided in this invention; however, those skilled in the art will recognize the applicability of other processes and / or the use of other materials.

[0024] In the description of this utility model, it should be understood that the terms "center", "longitudinal", "transverse", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential", etc., indicating the orientation or positional relationship are based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of describing this utility model and simplifying the description, and are not intended to indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this utility model.

[0025] In the description of this utility model, "first feature" and "second feature" may include one or more of the features.

[0026] In the description of this utility model, "multiple" means two or more.

[0027] In the description of this utility model, the first feature being "above" or "below" the second feature may include the first and second features being in direct contact, or it may include the first and second features not being in direct contact but being in contact through another feature between them.

[0028] In the description of this utility model, the terms "above", "over" and "on top" for the first feature and the second feature include the first feature being directly above or diagonally above the second feature, or simply indicate that the first feature is at a higher horizontal level than the second feature.

[0029] The battery housing 10 according to a first aspect embodiment of the present invention is described below with reference to the accompanying drawings.

[0030] like Figure 1 and Figure 2 As shown, the battery casing 10 according to the first aspect embodiment of the present invention includes: a casing body 1 and an insulating coating 2. The insulating coating 2 is disposed on the surface of the casing body 1. The thickness T of the insulating coating 2 satisfies the condition T = a * Rz of the surface roughness Rz of the casing body 1, where a ≥ 1.1. That is, the thickness of the insulating coating 2 is controlled within a range of not less than 1.1 times the roughness, where roughness refers to the unevenness of the surface of the casing body 1 with small spacing and small peaks and valleys, and Rz is the peak height of the uneven peaks and valleys on the surface of the casing body 1. In other words, the insulating coating 2 can effectively cover the peaks of the uneven peaks and valleys on the surface of the casing body 1.

[0031] Therefore, the thickness of the insulating coating 2 can be controlled according to the surface roughness of the housing body 1. The thickness of the insulating coating 2 is greater than the peak height of the uneven peaks and valleys on the surface of the housing body 1. There is at least a distance of 0.1 times the roughness between the outer surface of the insulating coating 2 and the peaks and apexes of the uneven peaks and valleys, so that the insulating coating 2 can completely cover the uneven peaks and valleys on the surface of the housing body 1 and ensure that there is a certain thickness margin. This can avoid insulation failure caused by leakage of the uneven peaks and valleys on the surface of the housing body 1, thereby improving the insulation protection performance of the insulating coating 2 for the housing body 1 and improving the safety performance of the battery housing 10.

[0032] Furthermore, the insulating coating 2 is typically formed by applying insulating material to the surface of the housing body 1 through spraying, printing, or other methods and then curing it. This significantly improves the adhesion between the insulating coating 2 and the housing body 1, thereby preventing insulation failure caused by the insulating coating 2 peeling off. In addition, since the insulating coating 2 is usually a high-molecular polymer coating, it has relatively high hardness, making it less susceptible to scratches or punctures, thus enhancing its insulating protective performance.

[0033] According to the battery casing 10 of the first aspect of the present invention, the thickness of the insulating coating 2 is controlled within a range of not less than 1.1 times the roughness. The thickness of the insulating coating 2 can be controlled according to the surface roughness of the casing body 1, so that the insulating coating 2 can completely cover the uneven peaks and valleys on the surface of the casing body 1, and can ensure that there is a certain coverage thickness margin. This can avoid insulation failure caused by leakage of uneven peaks and valleys on the surface of the casing body 1, thereby improving the safety performance of the battery casing 10.

[0034] According to some embodiments of this utility model, a ≥ 5. That is, the thickness of the insulating coating 2 is controlled within five times or more than five times the surface roughness of the shell body 1. This allows for a better increase in the thickness of the insulating coating 2, enabling it to completely cover the uneven peaks and valleys on the surface of the shell body 1 while having a larger coverage thickness margin. Specifically, it increases the distance between the outer surface of the insulating coating 2 and the peaks and apexes of the uneven peaks and valleys on the surface of the shell body 1, thereby reducing the risk of leakage and puncture. It also shortens the curing time of the insulating coating 2, improving its production efficiency, and simultaneously enhancing the adhesion between the insulating coating 2 and the shell body 1.

[0035] According to some embodiments of this utility model, a ≤ 25. That is, the thickness of the insulating coating 2 is controlled within a range not exceeding 25 times the surface roughness of the shell body 1. The thicker the insulating coating 2, the higher its internal stress. Therefore, the risk of warping, cracking, or even spontaneous detachment due to excessive thickness and high internal stress can be avoided. Simultaneously, the production efficiency of the insulating coating 2 can be avoided due to excessively thick curing time, and the production cost of the insulating coating 2 can be avoided. Therefore, by controlling the insulating coating 2 within a range not exceeding 25Rz, the adhesion between the insulating coating 2 and the shell body 1 can be improved, production efficiency can be increased, and the production cost of the insulating coating 2 can be reduced.

[0036] According to some embodiments of this utility model, 5 ≤ a ≤ 25. Therefore, while ensuring that the insulating coating 2 can completely cover the uneven peaks and valleys of the shell surface, the adhesion between the insulating coating 2 and the shell body 1 can be improved, as well as production efficiency, and the production cost of the insulating coating 2 can be reduced. For example, a can be 5, 6, 8, 10, 13, 16, 20, 22, 25, etc.

[0037] According to some embodiments of this utility model, the thickness T of the insulating coating 2 ranges from 0.88 μm to 100 μm. As shown in Table 1, if the thickness of the insulating coating 2 is too thin, it cannot guarantee complete coverage of the uneven peaks and valleys on the surface of the housing body 1, and there is a risk of it being punctured. If the thickness of the insulating coating 2 is too thick, the internal stress of the insulating coating 2 is too high, and the insulating coating 2 is at risk of warping, cracking, or even spontaneous detachment. Furthermore, the curing time of the insulating coating 2 is positively correlated with its thickness, leading to an increased curing time and the requirement for more production materials.

[0038]

[0039] Table 1. Effect of insulating coating thickness on insulation resistance and adhesion. Based on the insulation performance of an insulating coating 2 with a thickness of 0.88 μm, by controlling the thickness of the insulating coating 2 within the range of 0.88 μm to 100 μm, insulation failure caused by excessively thin insulating coating 2 can be avoided. Simultaneously, the adhesion between the insulating coating 2 and the housing body 1 can be improved, production efficiency increased, and the production cost of the insulating coating 2 reduced. For example, the thickness of the insulating coating 2 can be 0.88 μm, 1 μm, 5 μm, 10 μm, 20 μm, 40 μm, 60 μm, 80 μm, 100 μm, etc., without specific limitations.

[0040] According to some embodiments of this utility model, the thickness T of the insulating coating 2 ranges from 5μm to 80μm. As shown in Table 1, by controlling the thickness of the insulating coating 2 within the range of 5μm to 80μm, the adhesion percentage of the insulating coating 2 can be guaranteed to be above 80%, thereby ensuring the adhesion strength of the insulating coating 2 to the shell body 1. Furthermore, by increasing the minimum thickness of the insulating coating 2, the insulation effect of the insulating coating 2 can be guaranteed. By reducing the maximum thickness of the insulating coating 2, the adhesion between the insulating coating 2 and the shell body 1 can be further improved, as well as production efficiency and production cost of the insulating coating 2 can be reduced.

[0041] According to some embodiments of this utility model, the thickness T of the insulating coating 2 satisfies: T≥R*A / ρ, where R is the resistivity requirement of the insulating coating 2, A is the coverage area of ​​the insulating coating 2 on the surface of the housing body 1, and ρ is the conductivity of the insulating coating 2. It should be noted that the resistivity requirement of the insulating coating 2 refers to the resistivity requirement for the insulating coating 2 in the design requirements of the battery housing 10. By controlling the thickness of the insulating coating 2 to satisfy the above relationship, the withstand voltage rating of the insulating coating 2 can be better met, thereby improving the insulation performance of the insulating coating 2.

[0042] According to some embodiments of this utility model, the value of Rz ranges from 0.8μm to 10μm. That is, the roughness is controlled within the range of 0.8μm to 10μm, wherein the roughness is inversely proportional to the smoothness of the surface of the housing body 1. Therefore, by controlling the roughness within the range of 0.8μm to 10μm, it is possible to avoid the surface roughness of the housing body 1 being too small, which would reduce the adhesion of the insulating coating 2 on the surface of the housing body 1. At the same time, it is possible to avoid the surface roughness of the housing body 1 being too large, which would increase the amount of material required for the insulating coating 2 to cover the uneven peaks and valleys, and the coating of the insulating coating 2 might not be able to fully fill the trough areas of the uneven peaks and valleys, forming micro-voids, or causing air bubbles to form in the insulating coating 2, affecting the insulating effect of the insulating coating 2.

[0043] Therefore, by controlling the roughness within the range of 0.8μm to 10μm, the adhesion of the insulating coating 2 to the surface of the housing body 1 can be ensured while reducing the material input of the insulating coating 2 and guaranteeing the insulating effect of the insulating coating 2. The surface roughness of the housing body 1 can be 0.8μm, 1μm, 2μm, 3μm, 5μm, 7μm, 9μm, 10μm, etc.

[0044] According to some embodiments of this utility model, the insulating coating 2 is disposed on the outer surface of the housing body 1. Therefore, the insulating coating 2 can form a good insulating protective effect between the housing body 1 and an external object (such as an adjacent battery casing 10), thereby avoiding the risk of short circuits caused by contact between the housing body 1 and the external object, and thus improving the safety performance of the battery casing 10. Furthermore, by spraying the insulating coating 2 onto the outer surface of the housing body 1, the insulating coating can be directly sprayed or printed onto the outer surface of the housing body 1 and then cured. This provides greater operational flexibility for spraying, printing, and curing, reducing the production difficulty of the insulating coating 2. According to some embodiments of this utility model, the battery casing 10 is cylindrical, and the insulating coating 2 at least covers the outer peripheral surface of the casing body 1. When multiple cylindrical batteries are assembled into a battery device, the outer peripheral surfaces of adjacent battery casings 10 are in contact. Therefore, by covering the outer peripheral surface of the casing body 1 with the insulating coating 2, current conduction between adjacent cylindrical batteries can be effectively interrupted, thereby avoiding the risk of short circuits in the battery device and improving its safety performance.

[0045] According to some embodiments of this utility model, the insulating coating 2 includes a heat insulation layer. Therefore, while ensuring insulation, it can effectively block heat transfer between two adjacent battery casings 10, that is, it can achieve thermal isolation between two adjacent battery casings 10, thereby improving the safety performance of the battery casing 10.

[0046] According to some embodiments of this utility model, edge edges are formed between different sides of the housing body 1, and the insulating coating 2 covers at least part of the edge edges. Since the edge edges are located at the connection points between different sides of the housing body 1, they are relatively sharp. The insulating coating 2 can better adapt to objects of different shapes, thus allowing it to better cover the edge edges. Furthermore, because the insulating coating 2 has relatively high hardness, it is not easily punctured or scratched, thereby avoiding the risk of insulation failure caused by the edge edges scratching or puncturing the insulating coating 2, and thus ensuring the insulating protective performance of the insulating coating 2 for the housing body 1.

[0047] For example, in some embodiments, the housing body 1 is cylindrical, and the insulating coating 2 includes a first insulating part and a second insulating part. The first insulating part is disposed on the axial end face of the housing body 1, and the second insulating part is disposed on the outer peripheral surface of the housing body 1. The connection position of the first insulating part and the second insulating part is located at the connection between the axial end face and the outer peripheral surface of the housing body 1.

[0048] In other embodiments, the housing body 1 is square, and the intersection of any two adjacent outer surfaces of the housing body 1 is covered by an insulating coating 2.

[0049] According to some embodiments of this utility model, the housing body 1 is one of a steel shell, an aluminum shell, or a titanium shell. A steel shell has high strength, low cost, and good thermal conductivity, thereby improving the structural strength of the housing body 1, reducing its production cost, and enhancing its heat dissipation performance. An aluminum shell is lightweight, highly corrosion-resistant, and easy to process, thereby reducing the weight of the housing body 1, improving its corrosion resistance, and simplifying its processing. A titanium shell balances high strength and lightweight, exhibits excellent corrosion resistance, and is heat-resistant, thus controlling the weight of the housing body 1 while ensuring its structural strength and improving its heat resistance.

[0050] According to some embodiments of this utility model, the insulating coating 2 includes one of an epoxy resin layer, a polyurethane resin layer, or a silicone layer. The epoxy resin layer exhibits strong adhesion, chemical resistance, and insulation properties, low shrinkage, and high mechanical strength, thereby enhancing the insulating protective performance of the insulating coating 2. The polyurethane layer possesses strong abrasion resistance, weather resistance, insulation properties, and adhesion, and is simple and convenient to apply with a short drying time, thus improving the production efficiency of the insulating coating 2 while ensuring its insulating protective performance. The silicone layer exhibits strong heat resistance, weather resistance, insulation properties, elasticity, hydrophobicity, and chemical resistance, thereby enhancing the adaptability of the insulating coating 2 to different environments, and thus improving the reliability and stability of the insulating coating 2.

[0051] The battery cell 100 according to a second aspect embodiment of the present invention is described below with reference to the accompanying drawings.

[0052] According to a second aspect of the present invention, a battery cell 100 includes a battery housing 10 and an electrode assembly 20, with a motor assembly disposed within the battery housing 10.

[0053] According to the battery cell 100 of the second aspect of the present invention, the thickness of the insulating coating 2 is controlled within a range of not less than 1.1 times the roughness. The thickness of the insulating coating 2 can be controlled according to the surface roughness of the housing body 1, so that the insulating coating 2 can completely cover the uneven peaks and valleys on the surface of the housing body 1, and can ensure that there is a certain coverage thickness margin. This can avoid insulation failure caused by leakage of uneven peaks and valleys on the surface of the housing body 1, thereby improving the safety performance of the battery housing 10.

[0054] The third aspect of this utility model proposes a battery device. A battery device according to a third aspect of the present invention includes: a battery cell 100.

[0055] According to the battery device of the third aspect of the present invention, the thickness of the insulating coating 2 is controlled within a range of not less than 1.1 times the roughness. The thickness of the insulating coating 2 can be controlled according to the surface roughness of the housing body 1, so that the insulating coating 2 can completely cover the uneven peaks and valleys on the surface of the housing body 1, and can ensure that there is a certain coverage thickness margin. This can avoid insulation failure caused by the leakage of uneven peaks and valleys on the surface of the housing body 1, thereby improving the safety performance of the battery housing 10.

[0056] In some embodiments, the battery device includes a battery housing and a plurality of battery cells 100, which are connected in series or in parallel to form a battery cell module and housed in the battery housing to improve the energy density of the battery device.

[0057] In this utility model, unless otherwise explicitly specified and limited, the terms "installation," "connection," "joining," and "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components. For those skilled in the art, the specific meaning of the above terms in this utility model can be understood according to the specific circumstances.

[0058] In the description of this specification, the references to terms such as "one embodiment," "some embodiments," "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. Moreover, without contradiction, those skilled in the art can combine and integrate the different embodiments or examples described in this specification, as well as the features of different embodiments or examples.

[0059] Although embodiments of the present invention have been shown and described, those skilled in the art will understand that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the present invention, the scope of which is defined by the claims and their equivalents.

Claims

1. A battery casing, characterized in that, include: Shell body; An insulating coating is provided on the surface of the housing body. The thickness T of the insulating coating and the surface roughness Rz of the housing body satisfy the condition T = a * Rz, where a ≥ 1.

1.

2. The battery casing according to claim 1, characterized in that, a≥5; and / or, a≤25.

3. The battery casing according to claim 1, characterized in that, The thickness T of the insulating coating ranges from 0.88 μm to 100 μm.

4. The battery casing according to claim 3, characterized in that, The thickness T of the insulating coating ranges from 5μm to 80μm.

5. The battery casing according to claim 1, characterized in that, The thickness T of the insulating coating satisfies: T≥R*A / ρ, where R is the resistivity requirement of the insulating coating, A is the coverage area of ​​the insulating coating on the surface of the housing body, ρ is the conductivity of the insulating coating; and / or, the value of Rz ranges from 0.8μm to 10μm.

6. The battery casing according to claim 1, characterized in that, The insulating coating is provided on the outer surface of the housing body; and / or, the battery housing is cylindrical, and the insulating coating at least covers the outer peripheral surface of the housing body.

7. The battery casing according to claim 1, characterized in that, Edges are formed between different sides of the housing body, and the insulating coating covers at least a portion of the edges.

8. The battery casing according to claim 1, characterized in that, The housing body is one of steel, aluminum, or titanium; and / or the insulating coating includes one of epoxy resin, polyurethane resin, or silicone.

9. A single battery cell, characterized in that, include: Battery casing according to any one of claims 1-8; The electrode assembly is located inside the battery casing.

10. A battery device, characterized in that, include: The battery cell according to claim 9.

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