JPH04264358A - Manufacture of battery plate - Google Patents

Abstract

PURPOSE:To prevent burning due to current concentration and the soil, etc., of a welding pole caused by a splash with an active material adhering, increase welding strength, and reduce necessity for grinding and exchanging the welding plate. CONSTITUTION:The end part of a positive plate of a nickel-cadmium battery is pressurized in a longitudinal direction to be made a terminal fitting part, and nickel hydroxide is packed in other than the fitting part to be dried and rolled in this invention. Then a slender belt-like metal thin plate is seam-welded with an A.C. roller welding pole to the fitting part, and is punched in a given shape after that. Successively a lead tab composed of a nickel plating steel plate is placed on the said metal thin plate, a plane welding pole and two point welding poles are abutted to fitted part and lead tab sides respectively, and welding current is flowed to fit the lead tab to the positive plate in this manufacture.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method of manufacturing an electrode plate in which a sealing member and an electrode plate of the same polarity are electrically connected by a strip-shaped lead tab.

0002

[Prior Art] Batteries used in portable electrical equipment, etc. include manganese batteries, alkaline manganese batteries, etc., in which active materials and terminals are electrically connected by carbon rods or current collector rods, lithium batteries, nickel batteries, etc. Like a cadmium battery, an electrode group consisting of a positive electrode, a negative electrode, and a separator is housed in a metal case, and the terminal and the electrode plate with the same polarity are electrically connected by a metal lead tab or a current collector plate with a lead. What has been done is known. Among these, metal lead tabs are those that are integrated with the substrate, such as sintered nickel-cadmium batteries, or those that have a blank area on a three-dimensional structure substrate, such as paste-type electrode plates, and spot the lead tab on the blank area. Welded ones, and furthermore, those in which band-shaped metal current collector strips are attached in the longitudinal direction of these substrates and lead tabs are attached to the current collector strips by welding or the like are known, and some of them have been put into practical use.

0003

[Problems to be Solved by the Invention] However, when a lead tab made of a thin metal plate is directly spot welded to the uncoated area of a three-dimensional network structure substrate, splashes and welding defects are likely to occur, and the welding electrode becomes dirty. There were problems such as low efficiency and the need for frequent polishing and replacement of the welding electrodes.

The present invention eliminates the above-mentioned conventional drawbacks, and aims to provide a highly reliable electrode plate that provides a reliable electrical connection to a battery, and to improve weldability.

[0005]

[Means for Solving the Problems] The present invention connects a terminal cap or a sealing body that also serves as a terminal to a high-density mounting portion of a substrate having a three-dimensional network structure of polar plates of the same polarity, or A method of manufacturing a battery electrode plate, in which a thin metal plate is connected to a high-density mounting portion of a three-dimensional network structure substrate in advance to a sealing body, and electrically connected thereon with a thin metal lead tab. A feature is that a substantially planar welding electrode is arranged on the plate side and a plurality of point welding electrodes are arranged on the lead tab side, and two or more points are welded by electric resistance welding.

[0006]

[Function] By adopting point welding poles on the lead tab side and flat welding on the 3D board high-density mounting part side, we avoid current concentration at the high-density mounting part and prevent splash and welding defects. , it is possible to provide a reliable connection between the electrode plate and the lead tab, minimize staining and wear of the welding electrode, and improve weldability.

[0007]

DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings, taking a paste-type positive electrode plate for a nickel-cadmium storage battery as an example. In FIG. 1, the substrate 1 at the end of the nickel positive electrode plate 5 having a three-dimensional network structure is pressurized in the longitudinal direction.
After forming the collector terminal attachment part 2 with a thickness of 5 mm, the parts other than the attachment part 2 were filled with an active material mainly composed of nickel hydroxide.
Dry and roll. Next, a thin metal plate 3 with a width of 2 mm and a thickness of 0.08 mm is seam-welded with roller welding electrodes using alternating current as shown in Figure 2, on the collector terminal attachment part 2 where the substrate 1 with almost no active material attached is exposed. and install it. Thereafter, as shown in FIG. 3, it was punched out into a predetermined shape to produce a positive electrode plate 5.

Next, a lead tab 6 made of a nickel-plated steel plate with a thickness of 0.1 mm and a width of 4 mm is attached to the strip metal thin plate 3 of the positive electrode plate 5 and the collector terminal mounting portion 2 where the substrate 1 has been made highly dense. A planar welding electrode 7a is placed on the mounting portion 2 as shown in FIG. 4a, and two point welding electrodes 7b and 7b' are placed on the lead tab 6 side,
Pressure is applied to the thin metal plate 3 from above, and the welding electrodes 7b, 7
A welding current was passed between the welding electrode 7a and the welding electrode 7a while applying a constant pressure to the lead tab 6 at the welding point 4, respectively. Here, as a comparative example, as shown in the following table, 100 pieces each were obtained when two-point spot welding was performed using a pair of point welding electrodes as shown in Figure 5a, and when series spot welding was performed as shown in Figure 5b. The tensile welding strength, its variation, and the degree of polishing of the welding electrode were investigated.

[0009]

[Table 1]

[0010] From the above results, it is clear that the embodiments according to the present invention can provide stable welding performance with less variation in welding strength than the spot welding of the comparative example. This is related to the contact area between the current collector terminal attachment part 2 made of a three-dimensional network structure board with high density and the abutting welding electrode 7a, and if the current is too concentrated on the current collector terminal attachment part 2, the In addition, if the surface of the board high-density mounting part 2 is slightly contaminated with active material powder, etc., splash may occur, which may cause the welding electrode to become burnt out. Polishing will be required. Furthermore, in series welding, the range in which stable welding is possible is very narrow, and when a large current is applied, the current collector terminal mounting portion 2 and the thin metal plate 3 may be burnt out.

On the other hand, the welding electrode 7a that comes into contact with the substrate high-density mounting portion 2 according to the present invention is a flat surface and contacts the substrate high-density mounting portion 2 over a relatively large area, so that welding is not possible. Current can be dispersed and splash can be avoided. In this example, a flat electrode as shown in FIG. 4a is used as the electrode that comes into contact with the substrate densification attachment part 2, but a welding electrode having a gently curved surface as shown in FIG. 4b may also be used. It was also found that good weldability was obtained when the lead tab was welded directly to the high-density mounting portion of the board. Furthermore, the target battery electrodes are not limited to paste-type electrode plates for nickel-cadmium storage batteries, but can also be applied to battery electrode plates using a substrate having a three-dimensional network structure.

0012

Effects of the Invention According to the present invention, as described above, a substantially flat welding electrode that contacts the high-density portion of the three-dimensional network structure substrate;
In addition, by employing direct welding using a point welding electrode that contacts the lead tab, it is possible to increase welding strength and reduce variations in welding, resulting in highly reliable battery electrode plates, as well as polishing of the welding electrode. It is possible to improve welding ability by reducing the need for replacement and replacement, and its industrial value is great.

[Brief explanation of the drawing]

FIG. 1 is an enlarged sectional view of a main part of a process of welding a lead tab to a mounting portion of a positive electrode plate in an embodiment of the present invention.

FIG. 2 is a plan view of a positive electrode plate in which a thin metal plate is seam-welded to a substrate of the present invention.

FIG. 3 is a plan view of a positive electrode plate manufactured according to the present invention.

FIG. 4a is a perspective view of a planar welding electrode;

FIG. 4b is a perspective view of a gently curved welding electrode.

FIG. 5a is an enlarged sectional view of a main part of a spot welding process in a comparative example.

FIG. 5b is an enlarged sectional view of a main part of a series welding process in a comparative example.

[Explanation of symbols]

1...Substrate 2...Mounting part 3...Thin metal plate 4...Welding point 5... Positive electrode plate 6...Lead tab 7a...Welding pole 7b...Welding pole 7b'...Welding pole

Claims (2)

[Claims] [Claim 1] A method for manufacturing a battery electrode plate in which a sealing body that also serves as a terminal and an electrode plate having a three-dimensional network structure are electrically connected by a thin metal lead tab, the method of manufacturing the electrode plate having a high density of the substrate. A method for manufacturing a battery electrode plate, characterized by contacting a substantially planar welding electrode on the mounting part side and a plurality of point welding electrodes on the lead tab side, and carrying out electric resistance welding at two or more points. 2. The method for manufacturing a battery electrode plate according to claim 1, characterized in that a thin metal plate is connected in advance to the high-density attachment portion of the substrate, and a lead tab is welded onto the thin plate. .