CN212461837U

CN212461837U - Button cell positive electrode shell of pre-compaction circle

Info

Publication number: CN212461837U
Application number: CN202021565871.5U
Authority: CN
Inventors: 蒋长富; 伊良熺; 陈长辉; 谢道生
Original assignee: Shenzhen Jingfu Technology Co ltd
Current assignee: Shanghai Jingfu Technology Co.,Ltd.
Priority date: 2020-07-31
Filing date: 2020-07-31
Publication date: 2021-02-02
Anticipated expiration: 2030-07-31

Abstract

The utility model provides a button cell positive plate of pre-compaction circle, this positive plate are the open cylindrical structure in top only, thereby the bottom central point of positive plate puts and slightly inwards makes progress the arch and form a shallow slot in the bottom outside, and the outer border of this shallow slot and positive plate bottom outside along the external diameter =0.1 ~ 0.2 of distance/positive plate bottom between. The utility model discloses an anodal shell not only can not swell and warp to, it is outside ejecting also to avoid anodal shell when anodal ring discharge expansion, thereby avoids appearing battery internal resistance grow, influences discharge performance's phenomenon.

Description

Button cell positive electrode shell of pre-compaction circle

Technical Field

The utility model belongs to the technical field of lithium manganese button cell and specifically relates to a button cell positive plate shell of pre-compaction circle.

Background

The general structure of the existing lithium manganese button cell is as follows: the battery anode comprises an anode shell, wherein a press-formed anode ring (the anode ring is formed by pressing an anode material layer on the upper layer and a current collector on the lower layer together) is coaxially arranged at the center inside the anode shell, an inverted U-shaped diaphragm is coaxially arranged above the anode ring, and the upper part of the anode ring is inserted into the diaphragm. Generally, the bottom of the conventional positive electrode can has a flat plate structure. Because the positive polar ring of compression moulding can take place the inflation after having absorbed electrolyte, the positive polar ring after the inflation can outwards extrude positive pole shell downwards, and the bottom planar structure bearing pressure of positive pole shell is poor, leads to the phenomenon that the positive pole shell bottom appears bulging and warp easily.

Disclosure of Invention

An object of the utility model is to provide a button cell positive plate shell of pre-compaction circle, this positive plate shell not only can not swell and warp to, it is outside ejecting also to avoid the positive plate shell when positive polar ring discharge expansion, thereby avoids appearing the internal resistance grow of battery, influences discharge performance's phenomenon.

The positive pole shell of the pre-pressed round button battery is of a cylindrical structure with only an open top, the center of the bottom of the positive pole shell slightly protrudes inwards and upwards to form a shallow groove at the outer bottom, and the distance between the outer edge of the shallow groove and the outer edge of the bottom of the positive pole shell/the outer diameter of the bottom of the positive pole shell is = 0.1-0.2.

In the charge and discharge process of the button cell, the positive electrode ring placed in the positive electrode shell can expand, the deformation of the surface of the positive electrode ring in contact with the positive electrode shell is small in the expansion process, and the deformation of the surface of the positive electrode ring not in contact with the positive electrode shell is large, so that the expanded positive electrode ring is integrally bowl-shaped.

The utility model discloses a carry out "pre-compaction circle" to the bottom central point of positive pole shell, namely punch in the bottom central point of positive pole shell and form the shallow slot that slightly bulges inwards upwards, with the inflation deformation looks adaptation of anodal ring, simultaneously, also make the bottom anti-deformability of positive pole shell stronger; and, consider the inside space that positive plate shell inwards upwards protruding can compress positive plate shell to a certain extent, make the accommodation space of anodal ring diminish, therefore, the utility model discloses the outer border of injecing the shallow slot and the positive plate shell bottom outside along between the external diameter =0.1 ~ 0.2 of distance/positive plate shell bottom, make only in the central point department of being close to of positive plate shell bottom form the shallow slot, be close to the outer border position of bottom and still keep planar structure, the structure of this kind is compared with whole bottom formation shallow slot at positive plate shell, under the circumstances that the protruding height of shallow slot internal surface equals, the degree of compressing positive plate shell inside space will be some less, reserve bigger expansion space for the anodal ring, avoid the expansion of anodal ring to outwards ejecting positive plate shell, thereby guarantee to keep between anodal ring and the positive plate interior bottom surface, inseparable contact, reduce the internal resistance of battery by a large scale.

Preferably, the height of the protrusions on the inner surface of the shallow groove is 0.14-0.16 mm.

Drawings

Fig. 1 is a schematic axial sectional view of a positive electrode case of a pre-pressed round button battery according to any one of embodiments 1 to 3;

FIG. 2 is a schematic axial sectional view of a button cell according to any one of embodiments 1 to 3.

Detailed Description

The embodiments of the present invention will now be described in detail with reference to the accompanying drawings:

example 1

As shown in fig. 1, the positive electrode can of the button cell with the pre-pressed circle 10 has a cylindrical structure with only an open top, the bottom center of the positive electrode can 10 slightly protrudes inward and upward to form a shallow groove 11 at the outer bottom, the distance L between the outer edge of the shallow groove 11 and the outer edge of the bottom of the positive electrode can 10 is 2mm, the outer diameter D of the bottom of the positive electrode can 10 is 19.95mm, and the distance L between the outer edge of the shallow groove 11 and the outer edge of the bottom of the positive electrode can 10/the outer diameter D of the bottom of the positive electrode can 10 is approximately equal to 0.1; meanwhile, the height H of the projections of the inner surface of the shallow groove 11 is 0.15 mm.

As shown in figure 2, adopt the utility model discloses a CR2032 button cell is assembled into to the anodal shell of button cell of pre-compaction circle to test the internal resistance of battery.

Example 2

The utility model provides a button cell positive pole shell of pre-compaction circle which differs with embodiment 1 in that: the distance L between the outer edge of the shallow groove 11 and the outer edge of the bottom of the positive electrode shell 10 is 3mm, and the distance L between the outer edge of the shallow groove 11 and the outer edge of the bottom of the positive electrode shell 10/the outer diameter D of the bottom of the positive electrode shell 10 is approximately equal to 0.15; meanwhile, the height H of the projections of the inner surface of the shallow groove 11 is 0.14 mm.

The button cell positive electrode shell with the pre-pressed circle in the embodiment 2 is adopted to assemble a CR2032 button cell, and the internal resistance of the cell is tested.

Example 3

The utility model provides a button cell positive pole shell of pre-compaction circle which differs with embodiment 1 in that: the distance L between the outer edge of the shallow groove 11 and the outer edge of the bottom of the positive electrode shell 10 is 4mm, and the distance L between the outer edge of the shallow groove 11 and the outer edge of the bottom of the positive electrode shell 10/the outer diameter D of the bottom of the positive electrode shell 10 is approximately equal to 0.2; meanwhile, the height H of the projections of the inner surface of the shallow groove 11 is 0.16 mm.

The button cell positive electrode shell of the prepressed circle in the embodiment 3 is adopted to assemble a CR2032 button cell, and the internal resistance of the cell is tested.

Comparative example

The utility model provides a button cell positive pole shell of pre-compaction circle which differs with embodiment 1 in that: the distance L between the outer edge of the shallow groove 11 and the outer edge of the bottom of the positive electrode can 10 is 0.25mm (the thickness of the outer peripheral wall of the positive electrode can is 0.25 mm), namely, the whole bottom of the positive electrode can 10 is protruded inwards and upwards so as to form a shallow groove on the whole outer bottom; meanwhile, the height H of the projections of the inner surface of the shallow groove 11 is 0.15 mm.

And assembling the button cell positive electrode shell of the prepressed circle of the comparative example into a CR2032 button cell, and testing the internal resistance of the cell.

As shown in fig. 2, the button cell assembly structure is specifically as follows: the button cell comprises the positive electrode shell 10, wherein a positive electrode ring 30 which is formed by pressing is coaxially arranged in the center of the inside of the positive electrode shell 10, an inverted U-shaped diaphragm 40 is coaxially covered above the positive electrode ring 30, the upper part of the positive electrode ring 30 is inserted into the diaphragm 40, a negative electrode shell 20 is covered above the diaphragm 40, the negative electrode shell 20 is of a cylindrical structure with only an open bottom, a negative electrode piece 50 is clamped between the inner top wall of the negative electrode shell 20 and the diaphragm 40, and the upper opening and the lower opening of the negative electrode shell 20 and the positive electrode shell 10 are oppositely buckled to form a cylindrical button cell shell; a gap is left between the positive electrode can 10 and the negative electrode can 20, and an insulating seal ring 60 fills the gap to electrically isolate the positive electrode can 10 from the negative electrode can 20.

The utility model discloses an embodiment 1~3, comparative example and prior art's positive pole shell bottom are button cell's that the plane plate structure corresponds resistance data test result see below table 1:

TABLE 1

As can be seen from table 1: the utility model discloses a CR2032 button cell's that the positive shell equipment of button cell of pre-compaction circle formed internal resistance is minimum. The reason for this is that: the utility model discloses a bottom shape of positive polar shell 10 and positive polar ring 30's inflation deformation looks adaptation, simultaneously, anti deformability is also stronger to, positive polar ring 30 also can not be ejecting positive polar shell 10 outwards at the inflation of charge-discharge in-process, thereby guarantees to keep large tracts of land, inseparable contact between the interior bottom surface of positive polar ring 30 and positive polar shell 10, and then has effectively reduced the internal resistance of battery.

Claims

1. The utility model provides an anodal shell of button cell of pre-compaction circle, this anodal shell is the open cylindrical structure in only top, its characterized in that: the bottom center of the positive electrode shell slightly protrudes inwards and upwards to form a shallow groove at the outer bottom, and the distance between the outer edge of the shallow groove and the outer edge of the bottom of the positive electrode shell/the outer diameter of the bottom of the positive electrode shell is = 0.1-0.2.

2. The button cell positive electrode shell of pre-pressed circle of claim 1, wherein: the height of the protrusions on the inner surface of the shallow groove is 0.14-0.16 mm.