Button cell, electronic product and process for preparing button cell

Abstract

The present application relates to the field of lithium ion battery, disclose a kind of button cell and electronic product and the process for preparing button cell.The cover inner plate, cover outer plate between interval has first insulating layer;First metal sheet is insulated from cover outer plate, second metal sheet is connected in the bottom surface of cover outer plate, the end of first metal sheet, second metal sheet respectively exceeds the outer periphery of cover plate;Battery body, the first metal sheet of exceeding cover plate and the metal tab of each first pole piece are fixedly connected in stack, insulating cladding connection site, the second metal sheet of exceeding cover plate and the metal tab of each second pole piece are fixedly connected in stack;Battery body and embedded in battery body electrolyte are sealed in metal shell, cover plate is sealed in the opening of metal shell.The technical scheme is favorable to improve the assembly efficiency of button cell, improve the internal space utilization of button cell and then improve its electric capacity density.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of battery manufacturing, in particular to a button cell, an electronic product and a process for preparing the button cell. BACKGROUND

[0002] With the application of smart wearable products becoming more and more widespread, people's demand for small-size button secondary rechargeable batteries (referred to as button cells) is also increasing. Button lithium ion batteries are currently the most widely used. Button lithium ion batteries are increasingly used in smart wearable products, such as wireless Bluetooth earphones, etc. With the increasing application of button lithium ion batteries, such as earphones, the requirements for the batteries are also increasing. SUMMARY

[0003] One of the purposes of the embodiments of the present application is to provide a button cell, an electronic product and a process for preparing the button cell. The technical scheme is beneficial to improve the assembly efficiency of the button cell, improve the internal space utilization of the button cell and thus improve the capacity density thereof.

[0004] In a first aspect, the present embodiment provides a button cell, comprising:

[0005] a metal shell with an open end;

[0006] a battery body sealed in the metal shell, comprising a laminated core, the laminated core comprising a plurality of layers of first pole pieces, second pole pieces and separators spaced between any adjacent first pole pieces and second pole pieces, one of the first pole pieces and the second pole pieces being a positive pole piece and the other being a negative pole piece, each first pole piece having a first metal tab extending out of an outer edge of the laminated core and being laminated, and each second pole piece having a second metal tab extending out of another outer edge of the laminated core and being laminated;

[0007] a cover plate comprising a metal inner cover plate and a metal outer cover plate, an insulating layer being provided between the inner cover plate and the outer cover plate, a first metal sheet being connected to the bottom surface of the inner cover plate and being insulated from the outer cover plate, a second metal sheet being connected to the bottom surface of the outer cover plate, the ends of the first metal sheet and the second metal sheet respectively extending out of the outer periphery of the cover plate, the end of the first metal sheet extending out of the outer periphery of the cover plate being laminated and fixedly connected to each first metal tab, the connection part being covered with insulation, and the end of the second metal sheet extending out of the outer periphery of the cover plate being laminated and fixedly connected to each second metal tab, the seal being provided at the opening of the metal shell.

[0008] In a second aspect, the present embodiment provides an electronic product, the power supply being any of the button cells described above.

[0009] In a third aspect, the application provides a cover plate suitable for a button cell, comprising a cover inner plate made of metal, a cover outer plate, and an insulating layer between the cover inner plate and the cover outer plate,

[0010] A first metal sheet is insulated from the cover outer plate at the bottom surface of the cover inner plate, and a second metal sheet is connected to the bottom surface of the cover outer plate, and the ends of the first metal sheet and the second metal sheet respectively extend out of the outer periphery of the cover plate.

[0011] In a fourth aspect, the application provides a process for manufacturing a button cell, comprising:

[0012] The first metal sheet extending out of the outer periphery of the cover plate is tightly attached to the top surface of each first metal tab that is stacked together and extends out of the side surface of the stack body of the cell body, each first metal tab being a current collector foil of each first tab extending out of the side surface of the stack body, one end of the first metal sheet being connected to the bottom surface of the cover inner plate of the cover plate, and the other end extending out of the outer periphery of the cover plate, the first metal sheet being insulated from the cover outer plate,

[0013] After the first metal sheet and each first metal tab are stacked and fixedly connected, the length of the first metal sheet and the metal tab of each first tab extending out of the side surface of the stack body is cut short, and the first metal sheet and each first metal tab extending out of the side surface of the stack body and being stacked together are insulatively coated.

[0014] The second metal sheet extending out of the outer periphery of the cover plate is tightly attached to the top surface of each second metal tab that is stacked together and extends out of the side surface of the stack body, each second metal tab being a current collector foil of each second tab extending out of the side surface of the stack body, one end of the second metal sheet being connected to the bottom surface of the cover outer plate of the cover plate, and the other end extending out of the outer periphery of the cover plate,

[0015] After the second metal sheet and each second metal tab are stacked and fixedly connected, the length of the second metal sheet and the metal tab of each second tab extending out of the side surface of the stack body is cut short,

[0016] The cover plate comprises the cover inner plate made of metal and the cover outer plate, and a first insulating layer is spaced between the cover inner plate and the cover outer plate,

[0017] The cell body comprises the stack body, and the stack body comprises a plurality of layers of the first tabs, the second tabs, and the separators spaced between any adjacent first tabs and second tabs, one of the first tabs and the second tabs being a positive tab, and the other being a negative tab.

[0018] The battery body is placed in a metal shell, the cover plate seals the opening of the metal shell, and the battery body is sealed in the metal shell.

[0019] As can be seen from the above, by applying the technical scheme of the embodiment, since the embodiment adopts the technical scheme of pre-welding the first metal sheet and the second metal sheet on the cover plate, and stacking the two metal tabs together with the upper laminated sheet of the battery body during the electrode welding of the button cell, on one hand, the electrode connection of the button cell is facilitated, and on the other hand, since the technical scheme is adopted, the connection length of the electrode can be shortened after the electrode welding is completed, the occupation of the internal space of the metal shell by the electrode connection part is minimized, and the capacity density of the button cell is improved. BRIEF DESCRIPTION OF DRAWINGS

[0020] The accompanying drawings, which are included to provide a further understanding of the application and constitute a part of this application, illustrate embodiments of the application and together with the description serve to explain the application.

[0021] Figure 1 A top view structural schematic diagram of a cover plate suitable for a button cell is provided for the embodiment of the application;

[0022] Figure 2 A bottom view structural schematic diagram of the cover plate is shown in the figure; Figure 1

[0023] Figure 3 A perspective structural schematic diagram of the cover plate is shown in the figure; Figure 1

[0024] A top view structural schematic diagram of another cover plate suitable for a button cell provided by the embodiment of the application is shown in the figure, wherein the cover inner plate is provided with a liquid injection hole; Figure 4

[0025] A bottom view structural schematic diagram of the cover plate is shown in the figure; Figure 5 Figure 1

[0026] Figure 6 A perspective structural schematic diagram of the cover plate is shown in the figure; Figure 1

[0027] An assembly structural schematic diagram of the cover plate and the battery body before cutting is shown in the figure; Figure 7 Figure 4 An assembly structural schematic diagram of the cover plate and the battery body after cutting is shown in the figure.

[0028] Figure 8 Figure 7 A perspective structural schematic diagram of the cover plate is shown in the figure;

[0029] 21: cover outer plate; 22: cover inner plate;

[0030] ​​​​​23: first insulating adhesive layer;

[0031] 3: liquid injection hole;

[0032] 41: first metal sheet; 42: second metal sheet;

[0033] 51: first metal tab; 52: second metal tab. DETAILED DESCRIPTION

[0034] The present application will be described in detail below with reference to the accompanying drawings and specific embodiments. The schematic embodiments and descriptions of the present application are used to explain the present application, but are not intended to limit the present application. EMBODIMENT

[0035] Referring to Figures 1-8 .

[0036] The buckle type battery provided in the embodiment mainly comprises a battery body, a top-opened metal shell, and a cover plate arranged on the opening of the metal shell, and the battery body is sealed in the metal shell by the cover plate.

[0037] The battery body comprises a laminated body composed of a plurality of layers of first and second pole pieces and a separator interposed between any adjacent first and second pole pieces. One of the first and second pole pieces is a positive pole piece, and the other is a negative pole piece. The battery body can be, but is not limited to, a lithium ion battery body. The preparation process of the laminated body of the lithium ion battery body is described in the prior art.

[0038] The metal current collector foil of the first pole piece of each layer of the laminated body, which extends out of the side of the laminated body and is not coated with a polar material, is referred to as a first metal tab 51, and the upper and lower layers of the first metal tab 51 are stacked opposite to each other.

[0039] The metal current collector foil of the second pole piece of each layer of the laminated body, which extends out of the side of the laminated body and is not coated with a polar material, is referred to as a second metal tab 52, and the upper and lower layers of the second metal tab 52 are stacked opposite to each other.

[0040] The cover plate comprises a cover outer plate 21, a cover inner plate 22, and a first insulating adhesive layer 23 interposed therebetween.

[0041] As an illustration of the embodiment, the cover plate can have the following structure: the cover outer plate 21 and the first insulating adhesive layer 23 are arranged in a ring shape with a center through hole, the center through hole of the cover outer plate 21 is larger than the center through hole of the first insulating adhesive layer 23, when stacked, the inner edge of the first insulating adhesive layer 23 extends into the center through hole of the cover outer plate 21, and the cover inner plate 22 is arranged in the center through hole of the first insulating adhesive layer 23. The cover outer plate 21 and the cover inner plate 22 are respectively located on the two surfaces of the first insulating adhesive layer 23, and the adhesive on the two surfaces of the first insulating adhesive layer 23 is sealed and combined with the cover outer plate 21 and the cover inner plate 22 attached thereto to form an integrated body. For example, but not limited to, the adhesive on the two surfaces of the first insulating adhesive layer 23 is heated and melted to make the surfaces of the cover outer plate 21 and the cover inner plate 22 attached thereto fully contact and sealed and combined into an integrated body after cooling. Also, but not limited to, when the first insulating adhesive layer 23 is prepared by injection molding, the cover outer plate 21 and the cover inner plate 22 are placed in a predetermined mold, the hot-melt adhesive fully contacts the surfaces of the cover outer plate 21 and the cover inner plate 22 in the mold, and after cooling and setting, the first insulating adhesive layer 23 sealed and combined between the cover outer plate 21 and the cover inner plate 22 is obtained, that is, an integrated cover plate is obtained.

[0042] The bottom surface of the cover plate of the embodiment is respectively connected with independent first metal sheets 41 and second metal sheets 42, one end of the first metal sheet 41 is connected face-to-face to the bottom surface of the cover inner plate, and the other end extends outside the outer periphery of the cover outer plate 21. An insulating layer is arranged between the first metal sheet 41 and the bottom surface of the cover outer plate 21 to insulate and separate the first metal sheet 41 and the cover outer plate 21 to avoid short circuit.

[0043] One end of the second metal sheet 42 is connected face-to-face to the bottom surface of the cover outer plate 21, and the other end extends outside the outer periphery of the cover plate. As an illustration of the embodiment, the first metal sheet 41 and the second metal sheet 42 can respectively extend from the two sides of the cover outer plate 21, and the two metal sheets are completely not on the same side and completely staggered, which facilitates the welding connection of the metal sheets and avoids contact short circuit.

[0044] When preparing the cover plate, the length of the first metal sheet 41 and the second metal sheet 42 extending outside the outer periphery of the cover outer plate 21 is reserved to be relatively long, so as to be stacked and welded with the metal tab of the stacked body.

[0045] As an illustration of the embodiment, the cover plate is placed on the top surface of the stacked body of the battery body, the first metal sheet 41 is face-to-face attached to the top surface of the first metal tab 51 attached thereto, and the first metal sheet 41 and each first metal tab 51 form a stacked structure, and the stacked structure is tightly connected together, wherein the stacked structure can be, but not limited to, welded and connected.

[0046] Similarly, the second metal sheet 42 is tightly attached to the top surface of the second metal tabs 52 stacked together, and the first metal sheet 41 and the first metal tabs 51 are stacked together and tightly connected, and the stack is tightly connected together, which can be but not limited to welding connection.

[0047] As an example of the present embodiment, in the present embodiment, the first metal sheet 41 and the second metal sheet 42 provided on the cover plate are designed to extend oppositely from both sides of the cover plate, and correspondingly, the first metal tabs 51 and the second metal tabs 52 on the stack are oppositely extended on both sides of the stack. This technology is easier to position the electrode and facilitate the welding and assembly of the button cell.

[0048] The first metal sheet 41 and the first metal tabs 51 are cut and stacked together, and their connection is based on the tightness of the first metal sheet 41 and the first metal tabs 51, and the remaining small section is cut to shorten the extension length of the first metal sheet 41 and the first metal tabs 51 outside the stack. The remaining tightly connected first metal sheet 41 and first metal tabs 51 are coated with insulating material. As an example of the present embodiment, the tightly connected first metal sheet 41 and first metal tabs 51 (coated with insulating material) can be further bent downward on the side of the stack, and the tightly connected second metal sheet 42 and second metal tabs 52 (coated with insulating material) can be further bent downward on the side of the stack.

[0049] The battery body is placed into the cavity of the metal shell from the opening of the metal shell, and the cover plate seals the opening of the metal shell to seal the battery body in the metal shell.

[0050] In the present embodiment, the outer periphery of the cover outer plate 21 is the outer periphery of the cover plate, and the outer periphery of the cover outer plate 21 is sealingly connected to the opening of the metal shell, that is, the cover plate and the metal shell are sealingly connected. As an example of the present embodiment, the tightly connected end surface of the outer edge of the cover outer plate 21 and the metal of the end surface of the opening of the metal shell can be but not limited to sealingly connected together by laser welding under the action of high temperature, thereby achieving the sealing connection of the cover plate and the metal shell. In this way, the cover inner plate 22 on the cover plate serves as the first electrode of the button cell, and the cover outer plate 21 and the metal shell serve as the second electrode of the button cell, thereby providing an external power supply.

[0051] As an example of the present embodiment, when the electrolyte in the battery body of the present embodiment is an electrolyte, the electrolyte can be soaked into the stack before being placed into the metal shell, or the electrolyte can be filled from the opening of the metal shell before the cover plate is sealed.

[0052] Compared with the prior art of welding the metal tab of one polarity on the cover and the metal tab of the other polarity on the metal shell, the operation process of the prior art is more complex, and the prior art needs to design a long metal tab so that the metal tab of one polarity which is fixed together is bent from one side of the metal shell to the cover for welding, and the metal tab of the other polarity which is fixed together is bent from the other side of the metal shell to the bottom of the metal shell for welding, which needs to occupy a large internal space of the metal shell and is not conducive to improving the capacity density of the button cell.

[0053] According to the technical scheme of the embodiment, the first metal sheet 41 and the second metal sheet 42 are welded on the cover in advance, and the two metal tabs which are stacked together with the tab stack of the battery body are fixed together when the electrode of the button cell is welded, which facilitates the electrode connection of the button cell, and after the electrode welding is completed, the connection length of the electrode can be shortened, the internal space of the metal shell occupied by the electrode connection part is minimized, and the capacity density of the button cell is improved.

[0054] As an example of the embodiment, a liquid injection hole 3 can be arranged on the bottom cover of the metal shell or the inner cover plate 22 or the outer cover plate 21 of the cover, and after the cover is sealed, the electrolyte is injected through the liquid injection hole 3. The technical scheme of injecting after sealing is conducive to preventing the electrolyte from being contaminated on the metal shell or the cover and affecting the welding reliability of the metal shell and the sealing performance.

[0055] After the electrolyte injection is completed, the sealing pin seals the liquid injection hole 3. In order to improve the sealing effect of the sealing pin, laser welding is performed from the top surface of the sealing pin to form an annular welding track on the top surface of the sealing pin, and the liquid injection hole 3 is surrounded in the annular formed by the welding track and is at a certain distance from the welding track. At the position of the welding track, the bottom surface of the sealing pin is fused and sealed with the metal surface of the metal shell to which the sealing pin is attached to form an integrated body. The structure is conducive to reducing the influence of residual electrolyte on laser welding and ensuring the sealing effect of welding.

[0056] The above-described embodiments do not constitute a limitation on the protection scope of the technical scheme. Any modifications, equivalent replacements, and improvements made within the spirit and principles of the above-described embodiments shall be included in the protection scope of the technical scheme.

Claims

1. A button cell battery, characterized in that, include: A metal casing with an opening at one end; The battery body, sealed within the metal casing, includes a stacked plate body. The stacked plate body includes multiple layers of first electrode plates, second electrode plates, and a separator spaced between any adjacent first electrode plates and second electrode plates. One of the first electrode plates and the second electrode plate is a positive electrode plate, and the other is a negative electrode plate. The first metal tab of each first electrode plate extends out of one outer edge of the stacked plate body and is stacked with each other. The second metal tab of each second electrode plate extends out of the other outer edge of the stacked plate body and is stacked with each other. A cover plate, sealing the opening of the metal housing, includes an inner cover plate and an outer cover plate made of metal, with an insulating layer between the inner cover plate and the outer cover plate. One end of the first metal sheet is flatly welded to the bottom surface of the inner cover plate, and the other end extends out of the outer periphery of the cover plate. The end of the first metal sheet extending out of the outer periphery of the cover plate is tightly and fixedly connected to each of the stacked first metal tabs face to face. The ends of the first metal sheet and each of the first metal tabs along their length direction are cut-off end faces. The connection parts between the first metal sheet and each of the first metal tabs are insulated and covered. The first metal sheet is insulated and isolated from the outer cover plate. One end of the second metal sheet is flatly welded to the bottom surface of the outer cover plate, and the other end extends out of the outer periphery of the cover plate. The end of the second metal sheet extending out of the outer periphery of the cover plate is tightly connected to the metal tabs of each of the stacked second pole pieces face to face. The ends of the second metal sheets and each of the second metal tabs in the longitudinal direction of the stacked and welded together are cut end faces.

2. The button cell battery according to claim 1, characterized in that, The first metal sheet and the second metal sheet extend from opposite sides of the cover plate, respectively. The metal tabs of each first electrode and the metal tabs of each second electrode extend out from opposite sides of the battery body.

3. The button cell battery according to claim 1, characterized in that, The outer cover plate is provided with a through hole, the inner cover plate is sealed at the through hole, and the insulating layer is spaced between the inner cover plate and the outer cover plate; The outer cover plate is sealed to the end face of the opening of the metal shell.

4. The button cell battery according to claim 3, characterized in that, The bottom surface of the outer edge of the cover plate and the end face of the opening of the metal shell are fused together to form a single unit.

5. The button cell battery according to claim 1, characterized in that, The first metal sheets and each of the first metal tabs are stacked and welded together; The second metal sheets and each of the second metal tabs are stacked and welded together.

6. The button cell battery according to claim 1, characterized in that, The end of the first metal sheet is flush with the end of each of the first metal tabs; The end of the second metal sheet is flush with the end of each of the second metal tabs.

7. The button cell battery according to claim 1, characterized in that, Each of the first electrodes is a positive electrode, and each of the second electrodes is a negative electrode.

8. The button cell battery according to claim 1, characterized in that, The button cell battery is a lithium-ion battery.

9. The button cell battery according to claim 8, characterized in that, An injection hole for injecting electrolyte is provided on the metal casing, the inner plate of the cover, or the outer plate of the cover. A sealing pin is provided at the injection hole to seal the injection hole.

10. The button cell battery according to claim 1, characterized in that, Each of the first electrodes is a positive electrode, and each of the second electrodes is a negative electrode.

11. The button cell battery according to claim 1, characterized in that, The button cell battery is a lithium-ion battery.

12. The button cell according to claim 9, characterized in that, An injection hole for injecting electrolyte is provided on the metal casing, the inner plate of the cover, or the outer plate of the cover. A sealing pin is provided at the injection hole to seal the injection hole.

13. An electronic product characterized by, Its power source is a button cell battery as described in any one of claims 1 to 12.

14. A process for manufacturing coin cells, characterized in that, There is a cover plate, including, The cover has an inner and outer metal plate, with a first insulating layer separating the inner and outer plates. The first metal sheet has one end flatly welded to the bottom surface of the inner plate of the cover plate, and the other end protruding from the outer periphery of the cover plate. The first metal sheet is insulated from the outer plate of the cover plate. The second metal sheet has one end flatly welded to the bottom surface of the outer cover plate of the cover plate, and the other end protruding from the outer periphery of the cover plate; There is also a battery body, including a stacked body, which includes a plurality of stacked first electrode layers, a plurality of stacked second electrode layers, and a separator spaced between any adjacent first electrode layers and second electrode layers, wherein one of the first electrode layers and the other of the second electrode layer is a positive electrode layer and the other is a negative electrode layer. The process for preparing the coin cell includes: When the cover plate is placed on the top surface of the stacked body, the first metal sheet extending from the outer periphery of the cover plate is in close contact with the top surface of each first metal tab that extends from the side of the stacked body and is stacked together. Each first metal tab is a current collector foil of each first electrode sheet that extends beyond the side of the stacked body. The second metal sheet extending from the outer periphery of the cover plate is in close contact with the top surface of each second metal tab that extends from the side of the stacked body and is stacked together. Each second metal tab is a current collector foil that extends from the side of the stacked body of each second electrode sheet. The first metal sheets, which are placed face to face and closely attached, and the first metal tabs, which are stacked and connected together, are stacked and welded together. The second metal sheets, which are pressed together face to face, and the second metal tabs, which are stacked and connected together, are stacked and welded together. The length of the first metal sheet and the metal tabs of each of the first electrode sheets that are welded together and extend beyond the side of the stacked sheet body is shortened. The length of the second metal sheet welded together and the metal tabs of each of the second pole pieces extending out of the side of the stacked body is shortened; The first metal sheet and the connection parts of each of the first metal tabs, which are stacked and fixed together after being cut and extended from the side of the stacked body after being insulated and covered; The battery body, with the cover plate attached to its top, is placed inside a metal housing. The cover plate is then sealed to the opening of the metal housing, and the battery body is sealed inside the metal housing.

15. The process for preparing a coin cell according to claim 14, characterized in that, After sealing the cover plate at the opening of the metal housing, the system further includes: Electrolyte is injected into the metal casing through injection holes located on the metal casing, the inner plate of the cover, or the outer plate of the cover. A sealing pin covers the injection hole, sealing the injection hole.

16. The process for preparing a coin cell according to claim 14, characterized in that, After the first metal sheet and each of the first metal tabs, which are stacked and fixed together after being shortened and extended from the side of the laminated body, the following is also included: The first metal sheet and each of the first metal tabs are bent downwards along the root of the stacked sheet body and outwards from the side of the stacked sheet body. The second metal sheet and each of the second metal tabs are bent downwards along the root of the stacked body and outwards from the side of the stacked body.

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