JPH0367459A - sealed battery - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed description of the invention] Industrial applications The present invention relates to a current collector for a sealed battery.

2. Description of the Related Art In general, in a sealed battery such as a nickel-cadmium storage battery, a positive electrode current collector consists of a current collecting part 51 welded to cover the edge of the electrode plate and a lead led out from the current collecting part 51, as shown in FIG. It consists of a section 52.

Problems to be Solved by the Invention However, in the conventional configuration described above, the internal resistance of the lead part is large because the width of the lead part cannot be made wide and the distance to the sealing plate is long. However, this method had the disadvantage that the lead portion was twisted, making it difficult to weld to the sealing plate.

The present invention solves the above-mentioned conventional problems, and aims to provide a sealed battery in which internal resistance of the battery is reduced and defects in welding to the sealing plate due to twisting of the lead portion are reduced.

Means for Solving the Problems In order to achieve this object, the sealed battery of the present invention has positive,
an electrode body consisting of a cathode plate and a separator inserted between these electrode plates; a battery exterior can housing this electrode body; a sealing plate installed in a grooved portion of the exterior can via insulating packing; A battery comprising: a current collector that electrically connects between an electrode body and a sealing plate, wherein the current collector is formed by cutting and raising a part of a disc toward the center; It has a lead part welded to the sealing plate and a current collecting part welded to the protruding edge of the electrode plate provided on one end surface of the electrode body, and the lead part is welded from the center of the inner diameter of the grooved part of the outer can. The distance e to the rising portion of the grooved portion is O≦l<2 with respect to the radius rl of the inner diameter of the grooved portion, and the width W of the lead portion in the front current collector is W<2φ−, 2g2. be.

Effect With this configuration, by raising the lead part from the center of the current collector, the distance r2 to the sealing plate is shortened, and the width W of the lead part is widened, thereby reducing the internal resistance of the sealed battery. It is possible to reduce sealing plate welding defects due to twisting of the lead portion.

EXAMPLES Hereinafter, examples of the present invention will be described with reference to the drawings. FIG. 1 is a drawing showing an example of a current collector used in the present invention, and this current collector includes a current collecting part 11 and a lead part 12.
It is equipped with FIG. 2 is a longitudinal cross-sectional view of a sealed battery using the current collector, and the electrode body 22 is composed of positive and negative electrode plates and a separator inserted between these electrode plates. The current collecting portion 11 of the current collector is welded to the edge of the electrode plate provided on one end surface of the body 22 and projecting upward. This electrode assembly 22 is housed in a battery outer can 23 , the outer can 23 is grooved 25 , the lead part 12 of the current collector is welded to the back surface of a sealing plate 21 , and sealed via an insulating packing 24 . It is closed by tightening the plate 21 with the outer can 23.

Figures 3a and 3b show the dimensions of the current collector of the present invention. e is the distance from the center of the inner diameter of the grooved part 25 of the outer can to the rising part of the lead part 12. rl is the radius of the inner diameter of the grooved part 25 of the outer can 23, and r2 is the lead part 12.
W is the distance from the rising portion to the tip, and W is the width of the lead portion 12. The dimensional relationship of each part of these current collectors is shown in FIG.

An example in which this current collector is applied to a nickel-cadmium storage battery will be described below.

The current collector of the present invention was applied to a SC size (r+=10 m) nickel cadmium storage battery with a nominal capacity of 1200 mAh. Table 1 shows the dimensions of each part of the current collector used here, the internal resistance of the battery made from each current collector, the discharge voltage at 12A discharge, and the number of welding defects. The internal resistance was measured after the battery was prepared and charged at 1200 mA for 1 hour and 30 minutes. After that, discharge was performed at 12A. The number of welding defects was determined by measuring the number of defects that occurred when 10,000 electrode bodies were welded.

As a result, it was found that the battery of the present invention, which has better characteristics than the conventional battery, has a current collector in which e is shorter than 5 rIII+ (=2).

Further, the width W of the lead is set to W<2$ from the dimensional relationship shown in FIG. When Wξ2Jr, 2 y2, that is, when the present invention battery F (W=19) in Table 1, the internal resistance is the minimum, but the current collector lead comes into contact with the grooved part of the outer can and short-circuits. A problem occurred.

Effects of the Invention As described above, the present invention provides a current collector for a sealed battery, in which the distance me from the center of the inner diameter of the grooved portion of the outer can to the rising portion of the lead portion is determined by the radius rl of the inner diameter of the grooved portion. , O≦l<r1/2, and the width W of the lead part of the current collector is W<2 m, so that the distance r2 from the rising part of the lead part to the sealing plate is shortened, and the lead part By widening the width W, it is possible to reduce the internal resistance of the battery and to reduce defects in sealing plate welding due to twisting of the lead portion.

[Brief explanation of drawings]

Figure 1 is a perspective view of a current collector in an embodiment of the present invention, Figure 2 is a perspective view of a current collector in an embodiment of the present invention;
The figure is a vertical cross-sectional view of a sealed battery using the current collector shown in Figure 1, Figures 3a, b and 4 are diagrams showing the dimensional relationship of each part of the current collector, and Figure 5 is a conventional FIG. 3 is a perspective view of a current collector. 11... Current collector part, 12... Lead part,
21... Sealing plate, 22... Electrode body, 2
3...Outer can, 24...Insulating packing, 25...Grooved portion.

Claims (1)

[Scope of Claims] An electrode body consisting of positive and negative electrode plates and a separator interposed between these plates, a battery exterior can housing the electrode body,
A battery comprising: a sealing plate installed in the grooved part of the outer can via an insulating packing; and a current collector electrically connecting between the electrode body and the sealing plate, the current collector is a lead part that is welded to the sealing plate, which is made by cutting a part of a disc toward the center, and a current collector part that is welded to the edge of the electrode plate provided on one end surface of the electrode body. and a distance l from the center of the inner diameter of the grooved part of the outer can to the rising part of the lead part satisfies 0≦l<(r_1)/2 with respect to the radius r_1 of the inner diameter of the grooved part. , and a width W of the lead portion of the current collector satisfies the following: w<2√(r_1^2-l^2).