阅读说明：本技术 一种具有焊接保护垫圈的微型锂离子电池 (Miniature lithium ion battery with welding protection washer ) 是由 王昉 于 2021-01-19 设计创作，主要内容包括：本发明公开并提供了一种能有效防止在焊接过程中烧熔电芯组成部分,且能提高电池容量的具有焊接保护垫圈的微型锂离子电池。本发明包括外壳、电芯、盖板；盖板上设有中心孔,中心孔内设置有中心导电体,中心导电体和中心孔之间设置有绝缘体,中心导电体通过绝缘体密封住中心孔,外壳的上端设有开口,盖板的外沿焊接在开口上,且盖板密封住开口,电芯被封装在外壳内,电芯的正极与中心导电体电连接,电芯的负极与外壳电连接,另外盖板的内侧、中心导电体的内侧和外壳的内侧均设置有绝缘胶带,其电芯的上端设置有焊接保护垫圈,焊接保护垫圈挡住盖板与开口之间的接缝处。本发明应用于微型锂离子电池的技术领域。(The invention discloses and provides a miniature lithium ion battery with a welding protection gasket, which can effectively prevent a battery core component from being fused in a welding process and can improve the battery capacity. The invention comprises a shell, a battery cell and a cover plate; the cover plate is provided with a center hole, a center conductor is arranged in the center hole, an insulator is arranged between the center conductor and the center hole, the center conductor seals the center hole through the insulator, the upper end of the shell is provided with an opening, the outer edge of the cover plate is welded on the opening, the cover plate seals the opening, the electric core is packaged in the shell, the anode of the electric core is electrically connected with the center conductor, the cathode of the electric core is electrically connected with the shell, the inner side of the cover plate, the inner side of the center conductor and the inner side of the shell are both provided with insulating adhesive tapes, the upper end of the electric core is provided with a welding protection washer. The invention is applied to the technical field of miniature lithium ion batteries.)

1. A miniature lithium ion battery with a welding protection washer comprises a shell (1), a battery cell (2) and a cover plate (3); the battery is characterized in that a center hole is formed in the cover plate (3), a center conductor (5) is arranged in the center hole, an insulator (6) is arranged between the center conductor (5) and the center hole, the center conductor (5) seals the center hole through the insulator (6), an opening (7) is formed in the upper end of the shell (1), the outer edge of the cover plate (3) is welded on the opening (7), the cover plate (3) seals the opening (7), the battery core (2) is packaged in the shell (1), the positive pole of the battery core (2) is electrically connected with the center conductor (5), the negative pole of the battery core (2) is electrically connected with the shell (1), and in addition, insulating adhesive tapes (8) are arranged on the inner side of the cover plate (3), the inner side of the center conductor (5) and the inner side of the shell (1), the method is characterized in that: the upper end of the battery cell (2) is provided with a welding protection washer (9), and the welding protection washer (9) blocks a seam (10) between the cover plate (3) and the opening (7).

2. The miniature lithium ion battery with a weld protection gasket of claim 1, wherein: the welding protection washer (9) comprises an annular ring (91), a convex ring (92) is arranged on the outer edge of the lower surface of the annular ring (91), and the welding protection washer (9) is sleeved on the shoulder part of the upper end of the battery cell (2).

3. The miniature lithium ion battery with a weld protection gasket of claim 1, wherein: the material of the central conductor (5) is aluminum, copper, iron, nickel, stainless steel or nickel-plated stainless steel.

4. The miniature lithium ion battery with a weld protection gasket of claim 1, wherein: the welding protection gasket (9) is made of high polymer plastic which can not be dissolved in lithium ion liquid, and can be PP, PE, PI, PET, PEEK or silicon rubber.

5. The miniature lithium ion battery with a weld protection gasket of claim 1, wherein: the outer diameter of the welding protection washer (9) is consistent with the inner diameter of the shell (1), the inner diameter of the welding protection washer (9) is 0.5-2 mm smaller than the outer diameter of the welding protection washer (9), and the thickness of the welding protection washer (9) is 0.3-2 mm.

6. The miniature lithium ion battery with a weld protection gasket of claim 1, wherein: the insulator (6) is made of high polymer plastic which can not be dissolved in lithium ion liquid, and can be PP, PE, PI, PET, PEEK or silicon rubber.

7. The miniature lithium ion battery with a weld protection gasket of claim 1, wherein: electrolyte is also injected into a sealed space formed by the cover plate (3) and the shell (1); the battery cell (2) is formed by winding a positive plate, a negative plate and a diaphragm, the insulating adhesive tape (8) is arranged outside the battery cell (2), and the diaphragm is arranged between the positive plate and the negative plate.

8. The miniature lithium ion battery with a weld protection gasket of claim 1, wherein: a plug (11) is arranged at the winding center of the battery cell (2).

9. The miniature lithium ion battery with a weld protection gasket of claim 1, wherein: the cover plate (3) and the shell (1) are connected and sealed through laser welding.

Technical Field

The invention relates to a lithium ion battery, in particular to a miniature lithium ion battery with a welding protection gasket.

Background

The miniature lithium ion rechargeable battery is widely applied at present, and particularly along with the promotion of a wireless Bluetooth headset, the miniature lithium ion rechargeable battery is required to be small in size, high in specific energy and good in safety.

Chinese patents CN102804473B and CN104332647B each disclose a structure for a micro lithium ion battery to meet the market demand, but the outer side wall has three layers, and the multiple layers of side walls are not good for improving the specific energy of the battery.

Chinese patent application publication No. CN109980155A, which discloses a cover plate assembly for a lithium ion battery. This apron subassembly includes: the cover plate comprises a cover plate body, wherein a through hole is formed in the middle of the cover plate body, the through hole extends to form a cylinder body, and the cylinder body protrudes out of at least one surface of the cover plate body; the middle of the through hole is sealed by a glass body, and when the cover plate assembly is used for a micro battery, laser welding is adopted between the cover plate and the shell. A certain distance must be left between the welding part and the pole piece and the diaphragm, particularly the positive lug, the position is too close to the welding point in the production process, when the electrode needs to be widened further to improve the battery capacity, the welding process is easily affected by the heat of laser, the inside is burnt and melted, and finally the battery fails in advance.

Chinese patent application publication No. CN212342761U, which discloses an explosion-proof cover plate for a double-rivet lithium battery, comprising: briquetting is riveted to anodal, negative pole, insulating seal, apron aluminum sheet, positive pole connection piece, negative pole connection piece, anodal rivet and negative pole rivet, insulating seal sets up the both ends at the apron aluminum sheet respectively, insulating seal includes: the aluminum sheet cover plate comprises an upper sealing surface, a lower sealing surface, a middle connecting column and a sealing reinforcing rib, wherein an anode riveting block and a cathode riveting block are respectively arranged on the upper sealing surface at two ends of the cover plate aluminum sheet, the anode rivet sequentially penetrates through an anode connecting sheet and an insulating sealing piece to be connected with the anode riveting block in a riveting mode, and the cathode rivet sequentially penetrates through a cathode connecting sheet and the insulating sealing piece to be connected with the cathode riveting block. If adopt laser welding between this two rivet lithium cell explosion-proof cover plate and the casing, the inside fusing that appears equally can appear, finally appears the problem that the battery became invalid in advance.

Chinese patent application No. CN2020210057721 discloses a button cell, which comprises an upper cover, an insulating support, a winding body and a lower cover, wherein the upper cover and the lower cover are made of conductive materials, an impression for preventing explosion is arranged on the upper cover, the lower cover and the upper cover are respectively connected with the periphery of the insulating support in a releasable sealing manner, a rubber ring and a cover are put in through a shell rolling groove, and then the button cell is fastened and sealed. Although the method can solve the problems generated in the welding process, the rolling hook and the closing-in occupy partial space of the outer ring of the battery, so that the effective space in the battery is reduced.

Chinese patent application No. CN2020115941681, which discloses a cover plate assembly for a lithium ion battery having a compact explosion-proof and non-channeling sealing design. The cover plate is provided with an inner conductive metal body and an outer conductive metal body, wherein the outer conductive metal body has a double-layer structure and is clamped by an insulator; when the cover plate assembly is used for a micro battery, laser welding is adopted between the cover plate and the shell. A certain distance must be left between the welding part and the pole piece and the diaphragm, particularly the positive lug, the position is too close to the welding point in the production process, when the electrode needs to be widened further to improve the battery capacity, the welding process is easily affected by the heat of laser, the inside is burnt and melted, and finally the battery fails in advance.

Summary of the invention

The invention aims to overcome the defects of the prior art and provide a miniature lithium ion battery with a welding protection gasket, which can effectively prevent the cell components from being fused in the welding process and can improve the battery capacity.

The technical scheme adopted by the invention is as follows: the invention comprises a shell, a battery cell and a cover plate; the improved battery cover is characterized in that a center hole is formed in the cover plate, a center conductor is arranged in the center hole, an insulator is arranged between the center conductor and the center hole, the center conductor passes through the insulator to seal the center hole, an opening is formed in the upper end of the shell, the outer edge of the cover plate is welded on the opening, the cover plate seals the opening, the battery core is packaged in the shell, the positive electrode of the battery core is electrically connected with the center conductor, the negative electrode of the battery core is electrically connected with the shell, in addition, the inner side of the cover plate, the inner side of the center conductor and the inner side of the shell are all provided with insulating adhesive tapes, a welding protection gasket is arranged at the upper end of the battery core, and the welding protection gasket blocks the joint between the.

Further, the welding protection washer comprises an annular ring, a convex ring is arranged on the outer edge of the lower surface of the annular ring, and the welding protection washer is sleeved on the shoulder at the upper end of the battery cell.

Further, the material of the central electric conductor is aluminum, copper, iron, nickel, stainless steel or nickel-plated stainless steel.

Further, the welding protection gasket is made of polymer plastic which can not be dissolved in lithium ion liquid, and can be PP, PE, PI, PET, PEEK or silicon rubber.

Further, the outer diameter of the welding protection washer is consistent with the inner diameter of the shell, the inner diameter of the welding protection washer is 0.5-2 mm smaller than the outer diameter of the welding protection washer, and the thickness of the welding protection washer is 0.3-2 mm.

Further, the insulator is a polymer plastic which is not dissolved in the lithium ion electrolyte, and can be PP, PE, PI, PET, PEEK or silicon rubber.

Furthermore, electrolyte is injected into a sealed space formed by the cover plate and the shell; the battery cell is formed by winding a positive plate, a negative plate and a diaphragm, the insulating tape is arranged outside the battery cell, and the diaphragm is arranged between the positive plate and the negative plate.

Further, a plug is arranged at the winding center of the battery cell.

Further, the cover plate and the housing are connected and sealed by laser welding.

The invention has the beneficial effects that: in the laser welding process, the welding protection washer can effectively isolate the influence of high temperature of laser on the pole piece and the diaphragm, and can further increase the width of the battery cell and increase the capacity of the battery.

Drawings

FIG. 1 is a cross-sectional view of the weld protector gasket;

FIG. 2 is a cross-sectional view of a first embodiment of the present invention;

FIG. 3 is a cross-sectional view of a second embodiment of the present invention;

FIG. 4 is a cross-sectional view of a third embodiment of the present invention;

fig. 5 is a cross-sectional view of the cell after widening.

Detailed Description

Example one

In this embodiment, as shown in fig. 1, the invention includes a housing 1, a battery cell 2, and a cover plate 3; the cover plate 3 is provided with a central hole, a central conductor 5 is arranged in the central hole, an insulator 6 is arranged between the central conductor 5 and the central hole, the central conductor 5 seals the central hole through the insulator 6, the upper end of the shell 1 is provided with an opening 7, the outer edge of the cover plate 3 is welded on the opening 7, and the cover plate 3 seals the opening 7, the battery core 2 is packaged in the shell 1, the positive electrode of the battery core 2 is electrically connected with the central conductor 5, the negative electrode of the battery core 2 is electrically connected with the shell 1, in addition, the inner side of the cover plate 3, the inner side of the central conductor 5 and the inner side of the shell 1 are all provided with insulating adhesive tapes 8, the upper end of the battery core 2 is provided with a welding protection gasket 9, and the welding protection gasket 9 blocks a seam 10 between the cover plate 3 and the opening 7. The welding protection washer 9 comprises an annular ring 91, a convex ring 92 is arranged on the outer edge of the lower surface of the annular ring 91, and the welding protection washer 9 is sleeved on the shoulder of the upper end of the battery cell 2. Electrolyte is also injected into a sealed space formed by the cover plate 3 and the shell 1; the battery cell 2 is formed by winding a positive plate, a negative plate and a diaphragm, the insulating adhesive tape 8 is arranged outside the battery cell 2, the diaphragm is arranged between the positive plate and the negative plate, and a plug 11 is arranged at the winding center of the battery cell 2. The cover plate 3 and the housing 1 are connected and sealed by laser welding.

In the present embodiment, the central conductor 5 is a metal cover, and the metal cover is connected to the cover 3 by a clamping seal.

Example two

The difference between the present embodiment and the first embodiment is: the central conductor 5 is a rivet, and the rivet is riveted on the cover plate 3.

EXAMPLE III

The difference between the present embodiment and the first embodiment is: the central conductor 5 is a metal cylinder, the insulator 6 is a glass body, and the metal cylinder is hermetically connected to the cover plate 3 through the glass body.

In the above embodiment, the protection washer is annular, the middle of the annular part is hollow, the annular surface can be provided with a bulge and is L-shaped, the outer diameter of the protection washer is consistent with the inner diameter of the shell, the protection washer can be placed into the shell, the inner diameter is smaller than 0.5-2 mm, the thickness is 0.3-2 mm, the protection washer is made of high polymer materials which can not be dissolved in lithium ion liquid, such as PP, PE, PI, PET or silicon rubber, and PP is selected. As shown in fig. 5, the width of the battery cell may be further increased, so as to increase the capacity of the battery.

In laser welding, this protection packing ring can effectual isolation laser high temperature to the influence of pole piece and diaphragm, and the protection packing ring does not absorb electrolyte in addition, can annotate the liquid back weld, effectively stops electrolyte and receives the gasification phenomenon that high temperature influences and take place, and this problem can lead to the battery to produce interior pressure in welding process, makes the hole appear in the splice, final battery weeping.

While the embodiments of the present invention have been described in terms of practical embodiments, they are not to be construed as limiting the meaning of the present invention, and modifications of the embodiments and combinations with other embodiments will be apparent to those skilled in the art in light of the present description.