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, a side wall surrounding the periphery of the shell bottom, a skirt edge formed on the side wall at the tail end of the shell opening and bent towards the periphery, and a cover plate, the outer edge of the bottom face of the cover plate and the top face of the skirt edge are attached and combined together in a sealed mode, a through hole is formed in the cover plate, a metal end plate is combined on the through hole in a sealed mode, an annular insulating rubber layer is combined between the metal end plate and the cover plate in a sealed mode, one of the two surfaces of the metal end plate is exposed out of the inner surface of the cover plate, and the other surface of the metal end plate is exposed out of the outer surface of the cover plate. The laminated cell body is filled with electrolyte and is sealed in a 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-type batteries are increasingly used in smart wearable products, medical products, military products, etc. These products have an increasingly small demand for the size of steel shell button-type batteries, and the development of ultra-thin button-type batteries is extremely urgent. Summary of the Invention

[0003] One of the purposes of the embodiments 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 a button-type lithium-ion battery, characterized in that it 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 also forms a skirt that bends outward at the end of the shell mouth.

[0006] A cover plate, the outer edge of the bottom surface of the cover plate is attached to the top surface of the skirt and sealed together. A through hole is provided on the cover plate, and a metal end plate is sealed and combined on the through hole. An annular insulating glue layer is sealed and combined between the metal end plate and the cover plate. One of the two surfaces of the metal end plate is exposed on the inner surface of the cover plate, and the other is exposed on the outer surface of the cover plate.

[0007] A stacked electrode assembly, 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.

[0008] Optionally, the width of the skirt is 0.05 mm to 1 mm.

[0009] Optionally, the metal end plate is provided on the inner surface of the cover plate.

[0010] 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 is closely attached to the inner surface of the cover plate, the metal end plate is closely attached to the other surface of the annular insulating glue layer, and the boss protrudes out of the cover plate from the through holes of the cover plate and the annular insulating glue layer.

[0011] Optionally, the boss protrudes above the surface of the cover plate.

[0012] Optionally, the metal end plate is disposed on the outer surface of the cover plate.

[0013] On one surface of the metal end plate, there is a boss narrower than the through hole of the bottom of the shell and the annular insulating adhesive layer. One surface of the annular insulating adhesive layer is closely attached to the outer surface of the cover plate, the metal end plate is closely attached to the other surface of the annular insulating adhesive layer, and the boss extends into the cavity from the through holes of the cover plate and the annular insulating adhesive layer.

[0014] 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 by metal melting.

[0015] Optionally, the width of the sealing joint area between the cover plate and the skirt is the width of the skirt.

[0016] Optionally, the two electrodes of the stacked battery cell body extend out of both sides of the stacked battery cell body oppositely.

[0017] Optionally, the positive electrode of the stacked battery cell body is welded to the metal end plate.

[0018] 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 an electrode of the button-type lithium-ion battery.

[0019] 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 pole pieces, 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 shell opening as the end face of the shell wall is adopted, the existing processing technology of the steel shell 1 cannot obtain a shell opening with a flatness meeting the sealing welding requirements of the cover plate 2. However, by adopting the technical solution of this embodiment, after stamping a steel shell with the shell opening as the thickness end face of the shell wall, further stamping is performed to further bend the side wall at the shell opening outward to form a skirt surrounding the outer periphery of the shell 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 shell opening for sealing and combining with the cover plate, and ensuring the sealing reliability. Description of the Drawings

[0020] 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 of the present invention.

[0021] Figure 1 , 2 are respectively schematic three - dimensional structure diagrams of the button - type lithium - ion battery provided in the first embodiment of the present utility model;

[0022] Figure 3 , 4 are respectively schematic exploded structure diagrams of the housing of the button - type lithium - ion battery provided in the first embodiment of the present utility model.

[0023] 1: Steel shell; 13: Skirt; 2: Cover plate; 21: First through - hole;

[0024] 3: Annular insulating adhesive layer; 32: Second through - hole; 4: Metal end plate; 41: Boss. Detailed implementation manners

[0025] The present utility model will be described in detail below in conjunction with the drawings and specific embodiments. Here, the schematic embodiments of the present utility model and the descriptions are used to explain the present utility model, but not to limit the present utility model.

[0026] Examples of embodiments of the present invention are shown in the drawings below, where the same or similar reference numerals represent the same or similar elements or elements with the same or similar functions throughout.

[0027] The embodiments described below by referring to the attached 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.

[0028] In addition, the terms "first" and "second" are only used for descriptive purposes and cannot be construed as indicating or implying relative importance or implicitly indicating the quantity 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.

[0029] In the present invention, unless otherwise clearly defined and limited, terms such as "installation", "connection", "linkage", "fixation" shall be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral one; 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 of 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

[0030] See Figure 1-4 。

[0031] This embodiment provides a button-type lithium-ion battery, which includes a steel shell 1, a cover plate 2, and a battery cell 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 outward is also formed by stamping. The skirt 13 is bent outward to form a horizontal annular platform surrounding the shell opening.

[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. 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 combined together. Among them, it can be but is not limited to laser vertical welding to melt the facing metals at high temperature and hermetically combine them together to form an integrated hermetic connection.

[0033] The laminated battery cell body, filled with electrolyte, is sealed in the cavity formed by the cover plate 2 and the steel shell 1.

[0034] A through hole (denoted as the first through hole 21) is provided on the cover plate 2. The first through hole 21 can be but is not limited to a circular shape or other shapes. A metal end plate 4 is hermetically combined at the first through hole 21. The metal end plate 4 is hermetically combined at the through hole of the cover plate 2 through an annular insulating adhesive layer 3 with a second through hole 32 in the center that is narrower than the first through hole 21 of the cover plate 2, sealing the two through holes. And the metal end plate 4 is insulated from the cover plate 2 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 battery cell body, and the other surface is exposed outside the steel shell 1 to serve as the electrode end plate of the button-type lithium-ion battery.

[0035] One of the two electrodes of the laminated cell body is welded to the inner surface of the steel case 1 or the cover plate 2 to achieve electrical connection, and the steel case 1 and the cover plate 2 hermetically combined therewith 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, and the metal end plate 4 is used as the other pair of external electrodes of the button-type lithium-ion battery.

[0036] 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 of 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, the positive electrode is welded to the inward-facing surface of the metal end plate 4, and the metal end plate 4 is used as the positive electrode, and the negative electrode is welded to the inner surface of the steel case 1, and the steel case (such as the bottom of the case) is used as the negative electrode.

[0037] 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 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 being 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. By adopting the technical solution of this embodiment, after stamping the steel case 1 with the case opening being 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 13 surrounding the outer periphery of the case 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 case opening for hermetically combining with the cover plate 2 and ensuring the sealing reliability.

[0038] 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 sealing joint area between the cover plate 2 and the skirt 13 is the width of the skirt 13.

[0039] As an illustration of this embodiment, as shown in the figure, the metal end plate 4 can be disposed inside the cover plate 2. Specifically, a boss 41 narrower than the through holes of the cover plate 2 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 is closely attached to the inner surface of the cover plate 2, and the first through hole 21 and the second through hole 32 are aligned with each other. The second through hole 32 is located inside the first through hole 21. The metal end plate 4 is closely attached 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 steel shell 1 from inside the cover plate 2. When performing electrode welding, the positive electrode of the laminated 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 outward. Among them, the boss 41 is flush with the outer surface of the bottom of the shell or higher than the outer surface of the cover plate 2. 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 is closer to the cover plate 2 more tightly, 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.

[0040] In addition, the metal end plate 4 can be disposed outside the cover plate 2. One surface of the annular insulating adhesive layer 3 is closely attached to the outer surface of the cover plate 2. The second through hole 32 is located inside the first through hole 21. 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 shell from the second through hole 32. When performing electrode welding, the positive electrode is welded to the extended boss 41, and the metal end plate 4 located outside the cover plate 2 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 4 comes off, avoiding the problem that the battery explodes due to excessive internal pressure.

[0041] 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 the negative electrode of the lithium-ion battery are electrically connected to the positive electrode and the negative electrode of the driving circuit of the electronic product respectively, and this battery is used as the power supply for the driving circuit to drive the circuit of the electronic product.

[0042] As an illustration of this embodiment, it is possible but not limited to set power contacts opposite to the end plates of the button-type lithium-ion battery in the power accommodation space, and a spring is provided at the rear end of the power terminal. Through the elastic force, the power contacts of the driving circuit are respectively abutted 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.

[0043] As an illustration of this embodiment, the shape of the steel shell 1 in this embodiment can be flexibly designed according to the shape of the power accommodation space of the electronic product. For example, when the power accommodation space is a columnar space with a pentagonal cross-section, the bottom of the steel shell 1 can be designed to have a pentagonal cross-section accordingly. Similarly, when the power accommodation space is other irregular-shaped spaces, the bottom of the battery shell is designed to be a matching irregular shape, which is beneficial to making full use of the power accommodation space and maximizing the volume energy density of the button-type lithium-ion battery.

[0044] The above-described embodiments do not limit the protection scope of the technical solution. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principle of the above embodiments shall be included within the protection scope of the technical solution.

Claims

1. A button-type lithium-ion battery, characterized in that, including, a steel case, comprising: an open case mouth, a case bottom opposite to the case mouth, and a side wall surrounding the outer periphery of the case bottom. A skirt is formed at the end of the side wall and bends outwardly towards the outer periphery. a cover plate, the outer edge of the bottom surface of the cover plate is adhered to the top surface of the skirt and sealed together. A through hole is provided on the cover plate, 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 cover plate. One of the two surfaces of the metal end plate is exposed on the inner surface of the cover plate, and the other is exposed on the outer surface of the cover plate. a laminated battery cell body, filled with electrolyte, sealed in the cavity formed by the cover plate and the steel case. One of the two electrodes is electrically connected to the steel case or the cover plate, and the other is electrically connected to the metal end plate. The steel case 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 on the inner surface of the cover plate, a boss narrower than the through holes of the case 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 is closely attached to the inner surface of the cover plate, the metal end plate is closely attached to the other surface of the annular insulating adhesive layer, and the boss protrudes out of the cover plate from the through holes of the cover plate 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 cover plate.

5. The button-type lithium-ion battery according to claim 1, wherein the metal end plate is provided on the outer surface of the cover plate, a boss narrower than the through holes of the case 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 is closely attached to the outer surface of the cover plate, the metal end plate is closely attached to the other surface of the annular insulating adhesive layer, and the boss extends into the cavity from the through holes of the cover plate 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 same as the width of the skirt.

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

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

10. An electronic product, characterized in that, including a housing, an electronic module and the button-type lithium-ion battery according to any one of claims 1 to 9 are encapsulated in the housing, 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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