JPH11297315A - Manufacture of long electrode plate, and cylindrical secondary battery having the plate - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a manufacturing method for a long electrode plate which prevents burrs or protrusions from being generated in a cut end face of the plate, when an electrode original plate is prepared into a prescribed size without increasing the number of processes, and a cylindrical secondary battery provided with the plate. SOLUTION: In this manufacturing method, an electrode original plate 2 comprising a three-dimensional porous body filled with an active material is prepared, a pair of rotary bodies 1, 3 having acute included angles are arranged in an upper face and a reverse face of the original plate 2, and the pair of the rotary bodies 1, 3 are moved on the original plate 2 while they are rotated with a high speed to cut the original plate 2 into a prescribed size. This secondary battery of the present invention is a cylindrical secondary battery with a long electrode plate manufactured by the manufacturing method.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for manufacturing a long electrode plate and a cylindrical secondary battery provided with the electrode plate.

[0002]

2. Description of the Related Art Conventionally, a positive electrode plate of an alkaline secondary battery such as a nickel-cadmium secondary battery or a nickel-hydrogen secondary battery is filled with an active material paste in a three-dimensional metal porous body such as foamed nickel. A paste-type electrode plate that is dried, rolled, and cut into a predetermined size is used. Then, in order to form the paste type electrode plate into a predetermined size, the electrode base plate was cut using a slitter or a punching press.

Japanese Patent Application Laid-Open No. Hei 5-314966 discloses a continuous electrode plate in which an active material is adhered to a core made of a porous metal by continuously rubbing a pair of rotary blades. There is disclosed a technique for continuously manufacturing an electrode plate in which cutting burrs are formed in the same direction by cutting while cutting, or by continuously providing cuts at the time of cutting.

However, in any case, when cutting, burrs 6 and projections as shown in FIG. 4 are generated on the end face. When it is attempted to form an electrode group by laminating electrode plates having a polarity of, the burrs 6 and projections may penetrate the separator and cause a short circuit. In order to solve this problem, Japanese Patent Application Laid-Open No. 10-12229 discloses a method for manufacturing a positive electrode plate for an alkaline storage battery, which includes a step of polishing and removing a burr-generated end of a shear surface of a metal porous body. ing.

[0005]

However, in this manufacturing method, it is necessary to provide a polishing step of the end portion of the electrode plate in addition to the step of cutting the electrode plate, which causes a problem that the number of manufacturing steps is increased. there were. The present invention has been made in view of such problems, and without increasing the number of processes, when cutting an electrode plate into a predetermined size, burrs and projections do not occur on the cut surface of the electrode plate. It is an object of the present invention to provide a method for manufacturing a long electrode plate and a cylindrical secondary battery provided with the electrode plate.

[0006]

According to the present invention, in order to solve the above-mentioned problems, an electrode plate is prepared by filling a three-dimensional porous body with an active material, and a pair of upper and lower sharp edge angles are provided. A rotating body is disposed opposite to the rotating body, and the rotating body is rotated at a high speed and moved on the electrode base plate to cut the electrode base plate into a predetermined size. Further, the present invention provides a cylindrical secondary battery including a long electrode plate cut into a predetermined size as described above.

[0007]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will be described with reference to the drawings. The present invention is not limited to these embodiments.

The positive electrode plate, the negative electrode plate, the separator and the battery used had the following structures. Positive electrode plate substrate: A three-dimensional porous metal (foamed nickel) was used. Electrode plate: A paste is prepared by mixing a nickel hydroxide powder, a CoO powder, and an aqueous solution of carboxymethylcellulose with the above-described foamed nickel sheet, and the paste is filled in the foamed nickel and dried. This filler was immersed in a PTFE dispersion solution, dried, and then adjusted by roll rolling to produce an electrode base plate. Next, the electrode base plate was cut into a predetermined size to obtain a positive electrode plate.

Negative electrode plate Substrate: A punched metal having a plurality of openings formed in a houndstooth check pattern was prepared, and the surface of the punched metal plated with nickel was used.
The opening ratio of the punched metal sheet was 38%. Electrode plate: A hydrogen storage alloy having a predetermined composition was produced by an arc melting method, and the hydrogen storage alloy was pulverized into an alloy powder. Next, an alloy slurry composed of ion-exchanged water, the above-mentioned alloy powder, and carboxymethylcellulose was prepared, and then applied to a punched metal sheet, dried, and subsequently rolled to adjust the thickness. Further, this electrode plate was cut into a predetermined size to form a negative electrode plate.

Separator Nylon was used as the material of the separator. As the electrolyte, an alkaline electrolyte containing KOH as a main component was used.

Batteries The negative electrode plate and the positive electrode plate are wound with the separator interposed therebetween to form a spiral electrode group, and the electrode group is formed of nickel-plated stainless steel. The battery was housed in a cylindrical can, and the electrolytic solution having the above composition was poured into the cylindrical can, and a lid was provided to assemble an AA nickel-metal hydride battery having a rated capacity of 1200 mAh.

Example 1 A pair of diamond blades 1 and 3 each having a blade angle of 30 ° (see FIG. 1) are arranged facing the upper and lower surfaces of the electrode plate 2 and rotated at a high speed. A nickel-metal hydride battery provided with the positive electrode plate 4 cut by moving on the electrode base plate was manufactured. As a conventional example, a nickel-metal hydride battery provided with a positive electrode plate cut using a slitter was manufactured.

Example 2 A nickel-metal hydride battery provided with a positive electrode plate 4 cut in the same manner as described above except that the diamond blades 1 and 3 having a 45 ° edge angle shown in FIG. 1 were used.

[0014] In both the first embodiment and the second embodiment, FIG.
As compared with the cross section of the positive electrode plate 5 in the conventional example shown in FIG.
As shown in (1), an electrode plate having no burrs or protrusions of foamed nickel at the ends was obtained. When comparing the number of short circuits,
For 1000 electrode plates, 30 were generated in the conventional example, but only 2 were generated in each of Example-1 and Example-2, indicating that the cutting method according to the present invention is excellent. .

In the embodiment of the present invention, the cutting edge angle is 3
Although diamond blades of 0 ° and 45 ° were used, the point is that the cut surface of the electrode plate may be chamfered at an acute angle, and a diamond blade having an acute edge angle other than the aforementioned edge angle may be used. Good. Further, in the above-mentioned Example-1 and Example-2, an example in which cutting was performed using a diamond blade (two in the vertical direction) having the same angle in the vertical direction was described. It is also possible to cut using a diamond blade (two in the vertical direction) having different cutting edge angles (for example, when the upper side is 30 ° and the lower side is 45 °). Further, in the embodiments, a diamond blade is mentioned as an example of the rotating body, but the present invention is not particularly limited to this as long as the blade edge angle is acute.

A positive electrode plate manufactured by cutting an electrode plate into a predetermined size is formed by laminating a negative electrode plate with a separator interposed therebetween, and winding the wound negative electrode (the short side surface of the sheet-shaped electrode plate). ) May be chamfered, and if the number of cut positive electrode plates changes depending on the size of the electrode base plate, the long side surface of the electrode plate may be chamfered.

[0017]

As described above, according to the method for manufacturing a long electrode plate of the present invention, it is possible to produce an electrode plate free from burrs and projections generated when the electrode plate is cut. Therefore,
The production yield can be dramatically improved without going through the step of polishing and removing burrs and projections, and cost reduction can be achieved. In addition, by using such a long electrode plate, a secondary battery with extremely small number of short circuits and excellent performance can be realized.

[Brief description of the drawings]

FIG. 1 is a diagram showing a state in which an electrode plate is cut by a diamond blade.

2A and 2B are diagrams showing an electrode plate cut by the manufacturing method of the present invention, wherein FIG. 2A is a top view of the electrode plate, FIG. 2B is a front view of the electrode plate, and FIG. 2C is a perspective view of the electrode plate. It is.

3A and 3B are diagrams illustrating an electrode plate cut by a conventional manufacturing method, wherein FIG. 3A is a top view of the electrode plate, FIG. 3B is a front view of the electrode plate, and FIG. 3C is a perspective view of the electrode plate. is there.

FIG. 4 is an enlarged view of a main part of an electrode plate cut by a conventional manufacturing method.

[Explanation of symbols]

 REFERENCE SIGNS LIST 1 diamond blade 2 electrode base plate 3 diamond blade 4 electrode plate 5 electrode plate by conventional manufacturing method 6 burr generated on electrode plate by conventional cutting method

Claims (2)

[Claims] An electrode plate is prepared by filling a three-dimensional porous body with an active material, and a pair of rotating bodies having an acute edge angle are disposed on the upper and lower surfaces of the electrode plate so as to face each other. A method for producing a long electrode plate, comprising cutting the electrode plate into a predetermined size by moving the rotor on the electrode plate while rotating at a high speed. 2. A cylindrical secondary battery comprising a long electrode plate obtained by the production method according to claim 1.