Button type lithium ion battery and electronic product

Abstract

The utility model relates to the field of button type lithium ion batteries, and discloses a button type lithium ion battery and an electronic product. A steel shell of the battery comprises an open shell opening, a shell bottom opposite to the shell opening and a side wall surrounding the periphery of the shell bottom, a skirt edge bent towards the periphery is further formed at the position, at the tail end of the shell opening, of the side wall, a through hole is formed in the shell bottom, a metal end plate is combined with the through hole in a sealed mode, and an annular insulating rubber layer is combined between the metal end plate and the shell bottom in a sealed mode. One of the two surfaces of the metal end plate is exposed out of the cavity of the steel shell, the other surface of the metal end plate is exposed out of the cavity of the steel shell, the outer edge of the bottom surface of the cover plate and the top surface of the skirt edge are attached and combined together in a sealed mode, and the laminated cell body is filled with electrolyte and sealed in the cavity formed by the cover plate and the steel shell. One of the two electrodes is electrically connected with the steel shell or the cover plate, the other electrode is electrically connected with the metal end plate, and the steel shell and the metal end plate are used as the electrodes of the button type lithium ion battery.

Description

Technical Field

[0001] The utility model relates to the field of battery manufacturing, in particular to a button-type lithium-ion battery and an electronic product. Background Art

[0002] With the increasingly wide application of smart wearable products, the demand for secondary rechargeable batteries is also increasing. Button batteries are increasingly used in smart wearable products, medical products, military products, etc. These products have an increasingly small size requirement for steel shell button batteries, and the development of ultra-thin button batteries is extremely urgent. Summary of the Invention

[0003] One of the purposes of the embodiment of the utility model is to provide a button-type lithium-ion battery and an electronic product. Adopting this technical solution is beneficial to improving the sealing reliability.

[0004] In the first aspect, a button-type lithium-ion battery provided in this embodiment includes:

[0005] A steel shell, including: an open shell mouth, a shell bottom opposite to the shell mouth, and a side wall surrounding the outer periphery of the shell bottom. The side wall forms a skirt bent outward at the end of the shell mouth.

[0006] A through hole is provided on the shell bottom, and a metal end plate is hermetically bonded to the through hole. An annular insulating glue layer is hermetically bonded between the metal end plate and the shell bottom. One of the two surfaces of the metal end plate is exposed in the cavity of the steel shell, and the other is exposed outside the cavity of the steel shell.

[0007] A cover plate, the outer edge of the bottom surface of the cover plate is attached to the top surface of the skirt and hermetically bonded together.

[0008] A laminated cell body filled with electrolyte is sealed in the cavity formed by the cover plate and the steel shell. One of the two electrodes is electrically connected to the steel shell or the cover plate, and the other is electrically connected to the metal end plate. The steel shell and the metal end plate are used as the electrodes of the button-type lithium-ion battery.

[0009] Optionally, the width of the skirt is 0.05 mm to 1 mm.

[0010] Optionally, the metal end plate is arranged inside the shell bottom. A boss narrower than the through holes of the shell bottom and the annular insulating glue layer is provided on one surface of the metal end plate. One surface of the annular insulating glue layer closely adheres to the inner wall of the shell bottom, and the metal end plate closely adheres to the other surface of the annular insulating glue layer. The boss protrudes from the through holes of the shell bottom and the annular insulating glue layer outside the shell bottom.

[0011] Optionally, the boss protrudes above the surface of the shell bottom.

[0012] Optionally, the metal end plate is disposed on the outer surface of the bottom of the case. On one surface of the metal end plate, there is a boss narrower than the through hole of the bottom of the case and the annular insulating adhesive layer. One surface of the annular insulating adhesive layer is closely attached to the outer surface of the bottom of the case, the metal end plate is closely attached to the other surface of the annular insulating adhesive layer, and the boss exposes into the steel case from the through holes of the bottom of the case and the annular insulating adhesive layer.

[0013] Optionally, the cover plate is a metal cover plate, and the bottom surface of the cover plate is hermetically and integrally sealed with the skirt metal by melting.

[0014] Optionally, the width of the sealing joint area between the cover plate and the skirt is the width of the skirt.

[0015] Optionally, the two electrodes of the stacked battery cell body extend out from both sides of the stacked battery cell body in a facing manner.

[0016] Optionally, the positive electrode of the stacked battery cell body is welded to the metal end plate.

[0017] In a second aspect, an electronic product provided by an embodiment of the present invention includes a housing, in which an electronic module and any one of the above-mentioned button-type lithium-ion batteries are encapsulated, and a driving circuit of the electronic module is electrically connected to the electrodes of the button-type lithium-ion battery.

[0018] As can be seen from the above, when the solution of this embodiment is applied to an ultra-thin button-type lithium-ion battery, the stacked battery cell body is formed by laminating a plurality of electrode sheets, and the specific specifications are determined according to the size of the button-type lithium-ion battery. In this embodiment, the height of the steel case 1 of the ultra-thin button-type lithium-ion battery is less than or equal to 1.5 mm, and the processing difficulty of the steel case 1 is great. If the technical solution with the end face of the case opening as the end face of the case wall is adopted, the existing processing technology of the steel case 1 cannot obtain a case opening with a flatness that meets the sealing welding requirements of the cover plate 2. However, by adopting the technical solution of this embodiment, after stamping a steel case with the case opening as the thickness end face of the case wall, further stamping is performed to further bend the side wall at the case opening outward to form a skirt surrounding the outer periphery of the case opening. The top surface of the skirt is flat and is an integral structure with the inner wall of the side wall; the bottom surface of the skirt is an integral structure with the outer wall of the side wall. Adopting the skirt structure of this embodiment is beneficial to improving the flatness of the joint surface of the case opening for hermetically combining with the cover plate and ensuring the sealing reliability. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] The drawings described herein are used to provide a further understanding of the present invention, form a part of this application, and do not constitute an improper limitation to the present invention.

[0020] Figure 1 、 2 are respectively schematic three-dimensional structural diagrams of the button-type lithium-ion battery provided by Embodiment 1 of the present invention;

[0021] Figure 3 、 4 are respectively the exploded structural schematic diagrams of the housing of the button-type lithium-ion battery provided in the first embodiment of the present utility model.

[0022] 1: Steel shell; 11: First through hole; 13: Skirt; 2: Cover plate; 3: Annular insulating glue layer;

[0023] 32: Second through hole; 4: Metal end plate; 41: Boss. Detailed implementation manners

[0024] The present utility model will be described in detail below in conjunction with the accompanying drawings and specific embodiments. Here, the schematic embodiments and descriptions of the present utility model are used to explain the present utility model, but not to limit the present utility model.

[0025] Examples of embodiments of the present invention are shown in the accompanying drawings below, where the same or similar reference numerals represent the same or similar elements or elements having the same or similar functions throughout.

[0026] The embodiments described below by referring to the accompanying drawings of the present specification are exemplary and are intended to explain the present invention and should not be construed as limiting the present invention. In the description of the present invention, it should be understood that the terms "length", "width", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc. indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings, and 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, and thus should not be construed as limiting the present invention.

[0027] In addition, the terms "first" and "second" are only used for descriptive purposes and should not be construed as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Thus, the features defined with "first" and "second" may explicitly or implicitly include one or more of such features. In the description of the present invention, "a plurality" means two or more unless otherwise specifically defined.

[0028] In the present invention, unless otherwise clearly defined and limited, terms such as "installation", "connection", "linkage", "fixation", etc. shall be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or integrated; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, and it can be the internal communication between two components or the interaction relationship between two components. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood according to specific circumstances. Embodiment

[0029] See Figure 1-4 。

[0030] This embodiment provides a button-type lithium-ion battery, which includes a steel shell 1, a cover plate 2, and an electrode core body (not shown in the figure, and the specific preparation can refer to the prior art). The steel shell 1 is made of a stainless steel plate. One end of the steel shell 1 is a shell opening, and the closed end opposite to the shell opening is denoted as the shell bottom. The shell wall surrounding the shell bottom and between the shell bottom and the shell opening is the side wall. At the end of the side wall located at the shell opening, a skirt 13 bent outwardly is also stamped. The skirt 13 is bent outwardly to form a horizontal annular platform surrounding the shell opening.

[0031] A through hole (denoted as the first through hole 11) is provided on the shell bottom. The through hole can be, but is not limited to, circular or other shapes. A metal end plate 4 is hermetically bonded at the through hole. The metal end plate 4 is hermetically bonded at the through hole of the shell bottom through an annular insulating adhesive layer 3 with a second through hole 32 provided at the center and narrower than the first through hole 11 of the shell bottom, sealing the two through holes. Moreover, the metal end plate 4 is insulated from the steel shell 1 through the annular insulating adhesive layer 3. One of the two surfaces of the metal end plate 4 is exposed in the cavity of the steel shell 1 to be connected to an electrode of the laminated electrode core body, and the other surface is exposed outside the cavity of the steel shell 1 to serve as the electrode end plate of the button-type lithium-ion battery.

[0032] The cover plate 2 is in a flat shape, and its outer shape matches the outer edge of the skirt 13 at the shell opening of the steel shell 1. During assembly, the outer periphery of the cover plate 2 is aligned and flush with the outer periphery of the skirt 13, and the outer periphery of the bottom surface of the cover plate 2 is adhered to the top surface of the skirt 13 to be hermetically bonded together. Among them, it can be, but is not limited to, laser vertical welding to melt the facing metals at high temperature and hermetically bond them together to form an integrated hermetic connection.

[0033] The laminated cell body, filled with electrolyte, is sealed in the cavity formed by the cover plate 2 and the steel shell 1. One of the two electrodes of the laminated cell body is welded to the inner surface of the steel shell 1 or the cover plate 2 to achieve electrical connection, and the steel shell 1 and the cover plate 2 hermetically combined with it are used as a pair of external electrodes of the button-type lithium-ion battery. The other of the laminated cell body is welded to the inward-facing surface of the metal end plate 4 hermetically combined with the bottom of the shell through an insulating sheet, and the metal end plate 4 is used as the other pair of external electrodes of the button-type lithium-ion battery.

[0034] As an illustration of this embodiment, the positive electrode and the negative electrode of the laminated cell body are symmetrically distributed, and the two electrodes extend out from both sides of the laminated cell body facing each other to avoid short circuit between the positive and negative electrodes. For example but not limited to, welding the positive electrode to the inward-facing surface of the metal end plate 4 at the bottom of the shell, using the metal end plate 4 as the positive electrode, and welding the negative electrode to the inner surface of the cover plate 2 at the opening of the shell, using the cover plate 2 opposite to the metal end plate 4 as the negative electrode.

[0035] When applying the solution of this embodiment to an ultra-thin button-type lithium-ion battery, the laminated cell body is formed by laminating a plurality of electrode plates, and the specific specifications are determined according to the size of the button-type lithium-ion battery. In this embodiment, the height of the steel shell 1 of the ultra-thin button-type lithium-ion battery is less than or equal to 1.5 mm, and the processing difficulty of the steel shell 1 is great. If the technical solution with the end face of the opening of the shell as the end face of the shell wall is adopted, the existing processing technology of the steel shell 1 cannot obtain an opening of the shell with a flatness that meets the requirements for hermetic welding of the cover plate 2. However, by adopting the technical solution of this embodiment, after stamping the steel shell 1 with the opening of the shell as the thickness end face of the shell wall, further stamping is performed to further bend the side wall at the opening of the shell outward to form a skirt 13 surrounding the outer periphery of the opening. The top surface of the skirt 13 is flat and is an integral structure with the inner wall of the side wall; the bottom surface of the skirt 13 and the outer wall of the side wall are an integral structure. Adopting the skirt 13 structure of this embodiment is beneficial to improving the flatness of the joint surface of the opening of the shell for hermetically combining with the cover plate 2 and ensuring the sealing reliability.

[0036] As an illustration of this embodiment, the width of the skirt 13 of this embodiment can be 0.05 mm, 0.2 mm, 0.8 mm, 1 mm, etc., and is specifically determined according to the sealing requirements. The width of the hermetic combination area between the cover plate 2 and the skirt 13 is the width of the skirt 13.

[0037] As an illustration of this embodiment, as shown in the figure, the metal end plate 4 provided at the bottom of the case can be an inner end plate provided on the inner side of the bottom of the case. Specifically, a boss 41 narrower than the through hole of the bottom of the case and the annular insulating adhesive layer 3 is provided on one surface of the metal end plate 4, so that one surface of the annular insulating adhesive layer 3 closely adheres to the inner wall of the bottom of the case, and the first through hole 11 and the second through hole 32 are aligned with each other. The second through hole 32 is located within the first through hole 11. The metal end plate 4 closely adheres to the other surface of the annular insulating adhesive layer 3, and the boss 41 of the metal end plate 4 extends out from the second through hole 32 of the annular insulating adhesive layer 3, and the boss 41 is exposed outside the bottom of the case from within the bottom of the case. When performing electrode welding, the positive electrode of the stacked battery cell is welded to the inner surface of the metal end plate 4, and the boss 41 of the metal end plate 4 is used as the positive electrode of the button-type lithium-ion battery facing the outside. Among them, the boss 41 is flush with or higher than the outer surface of the bottom of the case. Adopting the inner end plate structure is also beneficial to improving the airtightness of the button-type lithium-ion battery. Specifically, during the use of the battery, under the action of the internal air pressure, the metal end plate 4 approaches the bottom of the case more closely, and the airtightness is stronger, which is beneficial to avoiding the problem that the airtightness of the battery is weakened due to the aging of the annular insulating adhesive layer 3.

[0038] In addition, the metal end plate 4 provided at the bottom of the case can be an outer end plate provided on the outer side of the bottom of the case. One surface of the annular insulating adhesive layer 3 is closely adhered to the outer surface of the bottom of the case. The second through hole 32 is located within the first through hole 11. The surface of the metal end plate 4 provided with a boss 41 narrower than the second through hole 32 is facing the outer surface of the annular insulating adhesive layer 3, and the boss 41 extends into the case body from the second through hole 32. When performing electrode welding, the positive electrode is welded to the extending boss 41, and the metal end plate 4 located outside the bottom of the case is used as the positive electrode. Adopting the outer end plate structure is beneficial to improving the safety performance of the button-type lithium-ion battery. Specifically, during the use of the battery, when the internal air pressure is greater than a certain air pressure, the metal end plate becomes loose, avoiding the problem that the battery explodes due to excessive internal pressure.

[0039] The button-type lithium-ion battery of this embodiment can be applied to electronic products. The button-type lithium-ion battery is installed in the power accommodation space of the electronic product, and the positive electrode and negative electrode of the lithium-ion battery are respectively electrically connected to the positive electrode and negative electrode of the driving circuit of the electronic product, and this battery is used as the power supply for the driving circuit to drive the circuit of the electronic product.

[0040] As an illustration of this embodiment, it is possible but not limited to setting power contacts opposite to the end plates of the button-type lithium-ion battery in the power accommodation space, and setting springs at the rear ends of the power terminals. Through the elastic force, the power contacts of the driving circuit are respectively pressed against the metal end plate 4 and the cover plate 2 of the button-type lithium-ion battery with a certain pressure, making the power connection of the electronic product simple and convenient.

[0041] As an illustration of this embodiment, the shape of the steel shell 1 of this embodiment can be flexibly designed according to the shape of the power accommodating space of the electronic product. For example, when the power accommodating space is a cylindrical space with a pentagonal cross-section, the shell bottom of the steel shell 1 can be designed to have a pentagonal cross-section. Similarly, when the power accommodating space is other special-shaped spaces, the shell bottom of the battery is designed to be a matching special shape, which is conducive to making full use of the power accommodating space and maximizing the volume energy density of the button lithium-ion battery.

[0042] The above-described implementation methods do not constitute a limitation on the protection scope of the technical solution. Any modification, equivalent replacement and improvement made within the spirit and principle of the above-described implementation methods shall be included in the protection scope of the technical solution.

Claims

1. A button-type lithium-ion battery, characterized in that, Comprising, A steel shell, including: an open shell mouth, a shell bottom opposite to the shell mouth, and a side wall surrounding the outer periphery of the shell bottom. The side wall further forms a skirt bent outward at the end of the shell mouth. A through hole is provided on the shell bottom, and a metal end plate is hermetically bonded to the through hole. An annular insulating adhesive layer is hermetically bonded between the metal end plate and the shell bottom. One of the two surfaces of the metal end plate is exposed inside the cavity of the steel shell, and the other is exposed outside the cavity of the steel shell. A cover plate, the outer edge of the bottom surface of the cover plate is attached to the top surface of the skirt and hermetically bonded together. A laminated cell body, filled with electrolyte, sealed in the cavity formed by the cover plate and the steel shell. One of the two electrodes is electrically connected to the steel shell or the cover plate, and the other is electrically connected to the metal end plate. The steel shell and the metal end plate serve as the electrodes of the button-type lithium-ion battery.

2. The button-type lithium-ion battery according to claim 1, wherein The width of the skirt is 0.05 mm to 1 mm.

3. The button-type lithium-ion battery according to claim 1, wherein The metal end plate is provided inside the shell bottom. A boss narrower than the through holes of the shell bottom and the annular insulating adhesive layer is provided on one surface of the metal end plate. One surface of the annular insulating adhesive layer closely adheres to the inner wall of the shell bottom, the metal end plate closely adheres to the other surface of the annular insulating adhesive layer, and the boss protrudes out of the shell bottom from the through holes of the shell bottom and the annular insulating adhesive layer.

4. The button-type lithium-ion battery according to claim 3, wherein The boss protrudes above the surface of the shell bottom.

5. The button-type lithium-ion battery according to claim 1, wherein The metal end plate is provided on the outer surface of the shell bottom. A boss narrower than the through holes of the shell bottom and the annular insulating adhesive layer is provided on one surface of the metal end plate. One surface of the annular insulating adhesive layer closely adheres to the outer surface of the shell bottom, the metal end plate closely adheres to the other surface of the annular insulating adhesive layer, and the boss protrudes into the steel shell from the through holes of the shell bottom and the annular insulating adhesive layer.

6. The button-type lithium-ion battery according to claim 1, wherein The cover plate is a metal cover plate, and the bottom surface of the cover plate is hermetically bonded to the skirt by metal melting.

7. The button-type lithium-ion battery according to claim 1, wherein The width of the sealing joint area between the cover plate and the skirt is the width of the skirt.

8. The button-type lithium-ion battery according to claim 1, wherein The two electrodes of the laminated cell body extend out of both sides of the laminated cell body oppositely.

9. The button-type lithium-ion battery according to claim 1, wherein The positive electrode of the laminated cell body is welded to the metal end plate.

10. An electronic product, characterized in that, Comprising a housing, in which an electronic module and the button-type lithium-ion battery according to any one of claims 1 to 9 are encapsulated, and the drive circuit of the electronic module is electrically connected to the electrodes of the button-type lithium-ion battery.

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