Button battery

Abstract

The present invention relates to a button battery, which comprises a housing and a core. The core is accommodated in the cavity of the housing. The core includes a positive electrode plate, a negative electrode plate and a separator disposed between the positive electrode plate and the negative electrode plate. A positive electrode tab is led out from the positive electrode plate, and a negative electrode tab is led out from the negative electrode plate. The housing includes a hard upper cover and a soft lower cover, and the hard upper cover and the soft lower cover are hermetically connected. The outer ends of the positive electrode tab and the negative electrode tab penetrate through the connection part of the hard upper cover and the soft lower cover. Compared with the prior art, by combining the hard upper cover and the soft lower cover, the hard upper cover is not easily deformed, improving the strength of the button battery. This not only effectively reduces the appearance defects generated during the production process and improves the yield rate of the button battery, but also enables the hard upper cover to protrude out of the installation groove during installation, greatly facilitating the convenience of installing the button battery at the terminal. At the same time, the soft lower cover provides a buffer space for the heat expansion of the core, avoiding explosion and ensuring the safety of the button battery.

Description

Technical Field

[0001] The present invention belongs to the technical field of batteries, and particularly relates to a button battery. Background Art

[0002] A button battery, also known as a coin cell, refers to a battery with an outer shape like a small button. Generally, it has a relatively large diameter and a relatively thin thickness. Especially for a soft-pack button battery, it has advantages such as good safety performance (unlike a hard-shell button battery that may explode) and light weight, so it has been widely used in various microelectronic products.

[0003] In the production process of existing soft-pack button batteries, an aluminum-plastic composite film is mainly used as the outer shell of the electrode core. However, due to the relatively soft texture of the aluminum-plastic composite film, it is prone to deformation during the production process, resulting in poor appearance. Moreover, when installing a soft-pack button battery, the soft-pack button battery is also prone to deformation under force, thus causing inconvenience in assembly and affecting the electrical connection quality of the soft-pack button battery. Summary of the Invention

[0004] The technical problem to be solved by the present invention is: to provide a button battery aiming at the problem that existing soft-pack button batteries are prone to deformation. [[ID=1�]]

[0005] To solve the above technical problem, an embodiment of the present invention provides a button battery, including a housing and an electrode core. The electrode core is accommodated in the cavity of the housing. The electrode core includes a positive electrode sheet, a negative electrode sheet, and a separator disposed between the positive electrode sheet and the negative electrode sheet. A positive electrode tab is led out from the positive electrode sheet, and a negative electrode tab is led out from the negative electrode sheet;

[0006] The housing includes a rigid upper cover and a flexible lower cover. The rigid upper cover and the flexible lower cover are sealingly connected. The outer ends of the positive electrode tab and the negative electrode tab penetrate through the connection part of the rigid upper cover and the flexible lower cover.

[0007] Optionally, the rigid upper cover is made of a steel-plastic composite film, and the flexible lower cover is made of an aluminum-plastic composite film. [[ID=Z7]]

[0008] Optionally, the steel-plastic composite film includes a steel foil layer and a PP layer, and the aluminum-plastic composite film includes a PP layer, a nylon layer, and an aluminum foil layer sandwiched between the PP layer and the nylon layer; the rigid upper cover and the flexible lower cover are integrally connected by heat-sealing the PP layer of the rigid upper cover and the PP layer of the flexible lower cover.

[0009] [[ID=ZL]]Optionally, the rigid upper cover includes a first cylindrical structure with an opening downward and a first annular flange disposed at the opening of the first cylindrical structure; the flexible lower cover is provided as a flat sheet-like structure; the flexible lower cover is sealingly connected to the first annular flange to seal the opening of the first cylindrical structure.

[0010] Optionally, the hard upper cover includes a first cylindrical structure with an opening facing downward and a first annular flange provided at the opening of the first cylindrical structure; the soft lower cover includes a second cylindrical structure with an opening facing upward and a second annular flange provided at the opening of the second cylindrical structure;

[0011] The first annular flange and the second annular flange are butted to form the cavity inside the hard upper cover and the soft lower cover; the positive tab and the negative tab pass through from the butting gap between the first annular flange and the second annular flange.

[0012] Optionally, the depth of the first cylindrical structure is greater than the depth of the second cylindrical structure.[[ID=_{7}]]

[0013] Optionally, a first sealant is provided at the connection between the positive tab and the positive plate, and a second sealant is provided at the connection between the negative tab and the negative plate.

[0014] Optionally, a section of the positive tab that is located inside the cavity and not provided with the first sealant and a section located in the butting gap between the first annular flange and the second annular flange are coated with a first tab glue, and a section of the negative tab that is located inside the cavity and not provided with the second sealant and a section located in the butting gap between the first annular flange and the second annular flange are coated with a second tab glue.

[0015] Optionally, the first cylindrical structure includes a first circular bottom and a first annular portion connecting the first circular bottom and the first annular flange, and the extending direction of the first annular portion is perpendicular to the first circular bottom;

[0016] The second cylindrical structure includes a second circular bottom and a second annular portion connecting the second circular bottom and the second annular flange, and the included angle between the extending direction of the second annular portion and the second circular bottom is an obtuse angle.

[0017] Optionally, the first annular portion and the first circular bottom are in smooth transition;

[0018] The second annular portion and the second circular bottom are in smooth transition.

[0019] Compared with the prior art, the button battery provided by the embodiment of the present invention combines a hard upper cover and a soft lower cover. The hard upper cover is not easily deformed, which improves the strength of the button battery. It not only effectively reduces the appearance defects generated during the production process and improves the yield rate of the button battery; but also can expose the hard upper cover outside the installation groove during installation, greatly facilitating the convenience of installing the button battery at the terminal; at the same time, the soft lower cover provides a buffer space for the heat expansion of the electrode core, avoiding explosion and ensuring the safety of the button battery. Description of the Drawings

[0020] Figure 1 is a schematic structural diagram of a button battery provided by an embodiment of the present invention;

[0021] Figure 2 is Figure 1 a cross-sectional view of;

[0022] Figure 3 is a schematic structural diagram of a button battery provided by another embodiment of the present invention.

[0023] The reference numerals in the specification are as follows:

[0024] 1. Housing; 11. Cavity;

[0025] 12. Rigid upper cover; 121. First annular flange;

[0026] 122. First cylindrical structure; 1221. First circular bottom; 1222. First annular part;

[0027] 13. Soft lower cover; 131. Second annular flange;

[0028] 132. Second cylindrical structure; 1321. Second circular bottom; 1322. Second annular part;

[0029] 2. Electrode core; 21. Positive electrode sheet; 22. First separator; 23. Negative electrode sheet; 24. Second separator;

[0030] 3. Positive electrode tab; 4. Negative electrode tab; 5. First sealing glue; 6. Second sealing glue; 7. First tab glue;

[0031] 8. Second tab glue. Detailed Embodiments

[0032] In order to make the technical problems, technical solutions and beneficial effects solved by the present invention clearer and more understandable, the present invention will be further described in detail below with reference to the drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention.

[0033] It should be understood that the terms "upper", "lower", etc. in the present invention indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings. They are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation. Therefore, it should not be construed as a limitation of the present invention.

[0034] As Figure 1 and Figure 2As shown, the button cell provided by the embodiment of the present invention includes a housing 1 and a core 2. The core 2 is accommodated in the cavity 11 of the housing 1. The core 2 includes a positive electrode sheet 21, a negative electrode sheet 23, and a separator disposed between the positive electrode sheet 21 and the negative electrode sheet 23. A positive electrode tab 3 is led out from the positive electrode sheet 21, and a negative electrode tab 4 is led out from the negative electrode sheet 23;

[0035] The housing 1 includes a rigid upper cover 12 and a flexible lower cover 13. The rigid upper cover 12 and the flexible lower cover 13 are hermetically connected. The outer ends of the positive electrode tab 3 and the negative electrode tab 4 penetrate through the connection portion of the rigid upper cover 12 and the flexible lower cover 13.

[0036] Compared with the prior art, the button cell provided by the embodiment of the present invention combines a rigid upper cover 12 and a flexible lower cover 13. The rigid upper cover 12 is not easily deformed, improving the strength of the button cell. It not only effectively reduces the appearance defects generated during the production process and improves the yield rate of the button cell, but also can expose the rigid upper cover 12 outside the installation groove during installation, greatly facilitating the installation convenience of the button cell at the terminal. At the same time, the flexible lower cover 13 provides a buffer space for the heat expansion of the core 2, avoiding explosion and ensuring the safety of the button cell.

[0037] Specifically, as Figure 2 shown, the separator includes a first separator 22 and a second separator 24. The first separator 22 is disposed between the positive electrode sheet 21 and the negative electrode sheet 23, and the second separator 24 is disposed on the surface of the negative electrode sheet 23 facing away from the first separator 22, or the second separator 24 is disposed on the surface of the positive electrode sheet 21 facing away from the first separator 22.

[0038] In one embodiment, the rigid upper cover 12 is made of a steel-plastic composite film, and the flexible lower cover 13 is made of an aluminum-plastic composite film; the structure is simple and convenient for processing.

[0039] Preferably, the steel-plastic composite film includes a steel foil layer and a PP layer, and the aluminum-plastic composite film includes a PP layer, a nylon layer, and an aluminum foil layer sandwiched between the PP layer and the nylon layer. The rigid upper cover 12 and the flexible lower cover 13 are integrated by thermally sealing the PP layer of the rigid upper cover 12 and the PP layer of the flexible lower cover 13. The hermetic connection between the rigid upper cover 12 and the flexible lower cover 13 is achieved by hermetically connecting the PP layer of the rigid upper cover 12 and the PP layer of the flexible lower cover 13. Thus, a wall is formed between the PP layer of the rigid upper cover 12 and the PP layer of the flexible lower cover 13. PP has good corrosion resistance, electrical insulation, and plasticity, avoiding corrosion of the cavity wall of the cavity 11 and facilitating the hermetic connection between the rigid upper cover 12 and the flexible lower cover 13.

[0040] In one embodiment, the core 2 is a wound core, making full use of the space inside the housing 1. Both the positive electrode tab 3 and the negative electrode tab 4 are led out from the outermost layer of the wound core to facilitate the penetration of the outer ends of the positive electrode tab 3 and the negative electrode tab 4 through the housing 1.

[0041] In another embodiment, the core electrode 2 is a stacked core.

[0042] In one embodiment, as Figure 3 shown, the rigid upper cover 12 includes a first cylindrical structure 122 with an opening facing downward and a first annular flange 121 provided at the opening of the first cylindrical structure 122; the soft lower cover 13 is provided as a planar sheet structure; the soft lower cover 13 is hermetically connected to the first annular flange 121 to seal the opening of the first cylindrical structure 122; the core electrode 2 is accommodated in the rigid upper cover 12, reducing the deformation problem of the button battery during the production process and improving the convenience of button battery assembly.

[0043] Specifically, the aluminum-plastic composite film is heat-sealed at the open end of the rigid upper cover 12, thereby forming the soft lower cover 13 hermetically connected to the rigid upper cover 12; the structure is simple and convenient for processing.

[0044] In another embodiment, as Figure 2 shown, the rigid upper cover 12 includes a first cylindrical structure 122 with an opening facing downward and a first annular flange 121 provided at the opening of the first cylindrical structure 122; the soft lower cover 13 includes a second cylindrical structure 132 with an opening facing upward and a second annular flange 131 provided at the opening of the second cylindrical structure 132;

[0045] The first annular flange 121 and the second annular flange 131 are butted to form a cavity 11 inside the rigid upper cover 12 and the soft lower cover 13; the positive electrode tab 3 and the negative electrode tab 4 pass through from the butting gap between the first annular flange 121 and the second annular flange 131; the first annular flange 121 and the second annular flange 131 are hermetically connected by a heat-sealing process, thereby realizing the hermetic connection between the rigid upper cover 12 and the soft lower cover 13, facilitating heat-sealing processing and also improving the sealing performance between the rigid upper cover 12 and the soft lower cover 13.

[0046] Preferably, the depth of the first cylindrical structure 122 is greater than the depth of the second cylindrical structure 132; most of the core electrode 2 is accommodated in the rigid upper cover 12, further improving the strength of the button battery, reducing the deformation problem of the button battery during the production process, and improving the convenience of button battery assembly.

[0047] In one embodiment, as Figure 2 shown, a first sealant 5 is provided at the connection between the positive electrode tab 3 and the positive electrode plate 21; the provision of the first sealant 5 can cover the welding mark between the positive electrode tab 3 and the positive electrode plate 21 and prevent damage to the positive electrode plate 21.

[0048] In one embodiment, as Figure 2 shown, a second sealant 6 is provided at the connection between the negative electrode tab 4 and the negative electrode plate 23; the provision of the second sealant 6 can cover the welding mark between the negative electrode tab 4 and the negative electrode plate 23 and prevent damage to the negative electrode plate 23.

[0049] In one embodiment, as Figure 2 shown, a section of the positive electrode tab 3 located inside the cavity 11 where the first sealant 5 is not provided and a section located in the butt joint gap between the first annular flange 121 and the second annular flange 131 are coated with the first tab glue 7; setting the first tab glue 7 enables the positive electrode tab 3 not to directly contact the first annular flange 121 and the second annular flange 131 at the butt joint gap between the first annular flange 121 and the second annular flange 131, thereby preventing the positive electrode tab 3 from reacting with the first annular flange 121 and the second annular flange 131 respectively to corrode the first annular flange 121 and the second annular flange 131.

[0050] A section of the negative electrode tab 4 located inside the cavity 11 where the second sealant 6 is not provided and a section located in the butt joint gap between the first annular flange 121 and the second annular flange 131 are coated with the second tab glue 8; setting the second tab glue 8 enables the negative electrode tab 4 not to directly contact the first annular flange 121 and the second annular flange 131 at the butt joint gap between the first annular flange 121 and the second annular flange 131, thereby preventing the negative electrode tab 4 from reacting with the first annular flange 121 and the second annular flange 131 respectively to corrode the first annular flange 121 and the second annular flange 131.

[0051] In one embodiment, as Figure 1 and Figure 2 shown, the first cylindrical structure 122 includes a first circular bottom 1221 and a first annular portion 1222 connecting the first circular bottom 1221 and the first annular flange 121, and the extending direction of the first annular portion 1222 is perpendicular to the first circular bottom 1221;

[0052] The second cylindrical structure 132 includes a second circular bottom 1321 and a second annular portion 1322 connecting the second circular bottom 1321 and the second annular flange 131, and the included angle between the extending direction of the second annular portion 1322 and the second circular bottom 1321 is an obtuse angle; the electrode core 2 can be better accommodated in the cavity 11, and it is also convenient to lead out the positive electrode tab 3 and the negative electrode tab 4.

[0053] Specifically, the first annular portion 1222 and the first circular bottom 1221 are in smooth transition.

[0054] Specifically, the second annular portion 1322 and the second circular bottom 1321 are in smooth transition.

[0055] The above are only the preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent replacements, and improvements made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A button battery, characterized in that, It includes a housing and an electrode core, the electrode core is accommodated in the cavity of the housing, the electrode core includes a positive electrode sheet, a negative electrode sheet and a separator disposed between the positive electrode sheet and the negative electrode sheet, a positive electrode tab is led out from the positive electrode sheet, and a negative electrode tab is led out from the negative electrode sheet; The housing includes a rigid upper cover and a flexible lower cover, the rigid upper cover and the flexible lower cover are hermetically connected, and the outer ends of the positive electrode tab and the negative electrode tab penetrate out from the connection part of the rigid upper cover and the flexible lower cover; The rigid upper cover includes a first cylindrical structure with an opening downward and a first annular flange disposed at the opening of the first cylindrical structure; the electrode core is accommodated in the rigid upper cover; The flexible lower cover is provided as a flat sheet-like structure; the flexible lower cover is hermetically connected to the first annular flange to seal the opening of the first cylindrical structure; Alternatively, the flexible lower cover includes a second cylindrical structure with an opening upward and a second annular flange disposed at the opening of the second cylindrical structure; the first annular flange and the second annular flange are butted to form the cavity inside the rigid upper cover and the flexible lower cover; The depth of the first cylindrical structure is greater than the depth of the second cylindrical structure; the flexible lower cover has a buffer space for buffering the thermal expansion of the electrode core, and the buffer space is located in the second cylindrical structure; A first sealant is provided at the connection part of the positive electrode tab and the positive electrode sheet, and a second sealant is provided at the connection part of the negative electrode tab and the negative electrode sheet; A section of the positive electrode tab that is not provided with the first sealant inside the cavity and a section located in the butting gap between the first annular flange and the second annular flange are coated with a first tab adhesive, and a section of the negative electrode tab that is not provided with the second sealant inside the cavity and a section located in the butting gap between the first annular flange and the second annular flange are coated with a second tab adhesive.

2. The button cell according to claim 1, characterized in that The rigid upper cover is made of a steel-plastic composite film, and the flexible lower cover is made of an aluminum-plastic composite film.

3. The button cell according to claim 2, wherein, The steel-plastic composite film includes a steel foil layer and a PP layer, and the aluminum-plastic composite film includes a PP layer, a nylon layer and an aluminum foil layer sandwiched between the PP layer and the nylon layer; the rigid upper cover and the flexible lower cover connect the PP layer of the rigid upper cover and the PP layer of the flexible lower cover into one body through a heat-sealing process.

4. The button cell according to claim 1, characterized in that, The first cylindrical structure includes a first circular bottom and a first annular part connecting the first circular bottom and the first annular flange, and the extending direction of the first annular part is perpendicular to the first circular bottom; The second cylindrical structure includes a second circular bottom and a second annular part connecting the second circular bottom and the second annular flange, and the included angle between the extending direction of the second annular part and the second circular bottom is an obtuse angle.

5. The button cell according to claim 4, wherein, The first annular part and the first circular bottom are smoothly transitioned; The second annular part and the second circular bottom are smoothly transitioned.

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