JPS6065452A - Alkaline storage battery - Google Patents

Abstract

PURPOSE:To prevent any deformation of plates and current collectors and achieve a high-rate discharge characteristic by welding current collectors to end peripheries of given plates protruding from the upper and the lower end surfaces of an electrode body consisting of a positive, a negative plate and a separator interposed between these plates. CONSTITUTION:A spiral electrode body 9 is formed by interposing a separator 3 between a positive and a negative plate 1 and 2 and rolling the thus formed body into a spiral form. Parts of the cores of the positive and the negative plates 1 and 2 protrude from the upper and the lower end surfaces of the electrode body 9. After a current collector 5 having a central penetrating hole and a holeless current collector 6 having no central penetrating holes are placed over the exposed parts of the cores, the current collectors 5 and 6 are partially molten by laser (a). At the same time, heat conducted through the current collectors 5 and 6 melts the ends of the cores to connect them together. Seam welding is performed and orbits (b) formed on the current collectors 5 and 6 by the seam welding extend from the center of the spiral electrode body 9 in the directions of normals. By the means mentioned above, an alkaline storage battery having an excellent high-rate discharge characteristic and in which no deformation of plates and current collectors is caused is constituted.

Description

DETAILED DESCRIPTION OF THE INVENTION (a) Industrial application field
It relates to alkaline storage batteries such as silver-zinc.

The same prior art alkaline storage battery 1 For example, the positive and negative electrode plates used are generally punched metal plates.
Then, a wire mesh or the like is used as an electrode base, and the active material paste is applied.
It is created by drying, or by filling a porous body obtained by coating and sintering a slurry mainly composed of Nizukel powder with an active material. The positive and negative electrode plates can be wound to form a spiral electrode body by inserting a 1'-hibarator between them, or a flat electrode body can be formed by stacking the positive and negative electrode plates alternately with separators interposed between them. It is used as.

Soil. The method for conducting electricity from each plate of the electrode body to the upper battery exterior terminal is to use a U-pole base body with conductive core tabs provided at one to several locations in advance, and connect the conductive tabs to the exterior terminals. Conventionally, a method of fixing the conductive tab to the electrode base by resistance welding, etc. has been commonly used. However, in this conductive method, the conductive tab extends from the electrode stem, so there is a loss of plastic material when removing the electrode base. There were various drawbacks, such as the cutting and punching processes performed by preforming the four-way tabs were complicated, and the position of the TEPCO was biased toward a part of the electrode plate, making high rate discharge disadvantageous.

In order to solve this inconvenience, US patents 3 and 7
An improved method has been proposed in No. 32,124 and Japanese Publication No. 54-315'75 (2). This improved method provides a core exposed portion of a constant width at the widthwise end C of the positive and negative electrode plates, This yang occurs when the electrode plate is wound in a spiral.

The exposed core part of the cathode plate is made to protrude from the upper and lower end faces of the spiral electrode body, and a current collector is fixed to these end faces by resistance welding, and the conductive tab part of the post-dyed current body is attached to the outer terminal. It is to be welded. An example of the shape of the East IE body used here is shown in Figures 1 (A) to (Di).

(Bl is a disc-shaped flat plate with multiple bent parts, and (C) is a punched metal with countless convex parts.

For example, a metal lath plate is used, and (D) is a flat plate with 62 circular openings in the center and a cylindrical ridge around the circular openings.

Since these @electric bodies are all welded by resistance welding, it can be said to be an excellent conductive production method that eliminates the drawbacks of using the electrode core with conductive tabs described above, but this improved method also has some problems. It turned out that there was a point.

In other words, there are variations in welding quality, burnout due to invalid upstream, and deformation of the electrode plate due to the pressure C2 applied to the electrode during welding, and the fabrication of the assembly also has the disadvantage of requiring complicated processing. .

4. Purpose of the Invention In view of the above, the present invention provides an alkaline storage battery in which the current collector is easy to manufacture, does not require complicated processing, does not cause deformation of the electrode plates or the current collector, and has excellent high-rate discharge characteristics. This is what we aim to provide.

B) Structure of the Invention The alkaline storage battery of the present invention comprises an electrode body consisting of positive and negative electrode plates and a separator inserted between these electrode plates. The electric body is fixed by laser welding.

(e) Examples Embodiments of the present invention will be described below with reference to the drawings.

FIG. 2 is a sectional view of the alkaline storage battery of the present invention, FIG. 3 is an explanatory diagram showing an example of laser welding between the assembly according to the present invention C2 and the edge of the electrode plate, and FIG. 4 is the assembly according to the present invention. FIG. 2 is a perspective view of a spiral electrode body with a welded body.

In these drawings≦2, (9) is an electrode body wound spirally between an anode plate il+ and a cathode plate (2) with one false separator (3) in between, and the upper and lower end surfaces. The exposed core portions of the positive and negative electrode plates protrude, respectively. This electrode body (9
) The upper and lower ends of the two protruding core exposed parts.

Four non-porous current collectors (5) each having a through hole in the center and a non-porous current collector (6) without a central through hole are mounted, and as shown in FIG. The Xtm of the core is increased by partially melting and conducting heat through the assembly.
a. They are fused and connected to each other. Here.

The laser can be either a solid state radar or a gas laser, but YAG (eventrium, aluminum, garnet) radar, which has a relatively small heat loss, is suitable, and seam welding is used because spout welding with a Keida laser cannot weld well. is valid.

The locus fbl of the seam welded current collector t is preferably normal to the center of the spiral polarized body, as shown in Figure 4, to ensure welding between the collector and the electrode plate. Fu-2 is done.

Similarly, when welding the current collector, it is effective to make the seam welding trajectory perpendicular to the electrode plate. be.

It should be noted that no adverse effect on the active material in the electrode plate and the separator due to laser welding was observed.

The upper and lower end surfaces thus fabricated were welded together by seam welding. The r4 pole body (9) is then inserted into the outer case (4), and the conductive tab portions of the U body (5) (61) are welded to the sealing body (7) and the outer case (4), respectively. (4) is sealed with the sealing body (7) via the pavking (8+) to form a completed battery.

N Effects of the Invention As described above, the present invention is to weld the body to the upper and lower end faces of the electrode body (the two protruding edges of the electrode plate) by laser welding. In particular, since no pressure is required, there is no need for electrode plates or assemblies, and it is possible to use a non-porous current collector that is easy to manufacture and does not require complicated processing. Since it is connected so as to cover one end surface of the electrode body, it is possible to provide an alkaline storage battery capable of high rate discharge.

[Brief explanation of the drawing]

Is Figure 1 a conventional alkaline storage battery? Figures 2 to 4 are perspective views of current collectors used in the present invention.
Figure 2 is a cross-sectional view of a 1-lkaline storage battery, Figure 3 is an explanatory diagram showing an example of radar welding between the assembly and the edge of the electrode plate, and Figure 4 is an illustration of the assembly and the edge of the electrode plate. FIG. 3 is a perspective view of a welded spiral electrode body. (1)... Anode plate, (2)... Cathode plate, (3)...
・Separator. (4) Exterior y-s+ (51 (61... Current collector, (7)... Sealing body. (8)...; i King, (9)... 1 Sokoku body, (a
)···laser. (bl... Laser trajectory.

Claims (1)

[Claims] (1) An aggregate body is fixed by laser welding on the edge of a predetermined top plate that protrudes from each of the upper and lower end surfaces 62 of an electrode body consisting of positive and negative electrode plates and a separator inserted between these plates. alkaline storage battery.