JP2003007307A - Manufacturing method of grid for storage battery - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an expanded grid hardly broken by proceeding corrosion. SOLUTION: Several parallel slits are made zigzag a in the proceeding direction of an alloy sheet, a line portion formed by the adjacent slits in the width direction of the alloy sheet is plastic-deformed in convex alternatively in both directions front and back from the alloy sheet face, a plain area formed at a non-slit portion is made a node of the said convex line portion, and a mesh portion is formed by spreading this alloy sheet in the width direction. In a manufacturing method of the grill for a storage battery, the slit are made zigzag passing through the alloy sheet to a pair of rolls opposing rolls layered with a disc cutter including the convex processing portion projected in the same distance from the circumference. It is the manufacturing method of the grill for the storage battery using the disc cutter of which concaves are provided to a thickness direction alternatively to both sides of the disc cutter opposing to the said node in the said convex processing portion, and also the circumference portion of at least a non-convex processing portion on a circumferential face of the cutter is beveled to low for face with each concave.

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 storage battery grid.

[0002]

2. Description of the Related Art In recent years, in order to improve the productivity of storage batteries, in particular, in addition to the production by the casting method,
An expanding method in which slits are continuously formed on a sheet material such as a rolled alloy body to perform an expanding process has been widely used. At present, the rotary method is mainly used as a method for producing the expanded lattice. The manufacturing method can be divided into two steps as described below.

In the first step, a plurality of parallel slits are formed so as to form a zigzag shape along the traveling direction of the alloy sheet, and the line portion formed by the slits adjacent in the alloy sheet width direction is formed into an alloy sheet. This is a step (FIG. 1) of plastically deforming alternately from the surface in the front and back directions to form a convex shape so that a flat region formed by the non-slit portion becomes a knot portion of the convex line portion.

In order to form the flat area formed by the non-slit portion, concave portions are alternately provided in the thickness direction on both side walls of the disk-shaped cutter. Regarding the method of providing this recess, JP-A-10-223232 and JP-A-2000-1061
As described in No. 90, there is a method of forming a rectangular concave portion in addition to providing a rectangular inclined portion such that the cutter thickness continuously decreases from the side wall surface of the cutter toward the outer peripheral portion of the cutter. However, in the prior art, while cutting the sheet material by the outermost peripheral portion of the recessed portion of the cutter, while deforming the sheet material with the outermost peripheral portion as a fulcrum, the sheet material is placed at the outermost peripheral portion. There was an outermost peripheral surface of the cutter that was substantially parallel to the surface of the sheet material when passed.

The second step is a step of forming a mesh portion by expanding the alloy sheet having the line portion formed in the width direction. Usually, after the grid body is filled with the active material paste in the subsequent steps, it is cut into a predetermined size to form an electrode plate.

[0006]

In the above-described manufacturing process of the rotary type expanded lattice, the alloy sheet is formed by the recesses provided alternately on both side walls of the disk-shaped cutter in the first step described above. Forms a nodal portion of the line portion by forming a portion that is not slit by a cutter. This state is shown in FIG. As is clear from FIG. 3, at this time, in order to cut and slit adjacent knot portions, both ends of the knot portion in the cross-sectional direction are the blades of the cutter for slitting, that is, the cutter portion on the side where no recess is provided. Is cut up and down. With conventional cutters, the sheet nodules are cut while being pressed against the ridgeline of the recessed part on the outermost periphery of the cutter, so cracks occur at the nodules at this part, and corrosion progresses from these cracks. However, due to the breakage, the capacity of the storage battery and the life of the storage battery were shortened.

[0007]

According to a first aspect of the present invention, which has been made to solve the above-mentioned problems, a plurality of mutually parallel slits are formed in a zigzag pattern along the traveling direction of an alloy sheet to form an alloy sheet width. Direction, the linear portion formed by the slits adjacent to each other is plastically deformed alternately in the front and back directions from the alloy sheet surface in a convex shape, and the flat area formed by the non-slit portion becomes the nodal portion of the convex linear portion. To form a mesh portion by expanding this alloy sheet in the width direction, in the method of manufacturing a storage battery grid used as a grid, the staggered slits, etc. Formed by passing an alloy sheet through a pair of rolls, which are made by laminating rolls of disk-shaped cutters having convex processing portions protruding at intervals, and between the convex processing portions correspond to the knot portions. The recesses are alternately provided in the thickness direction on both side surfaces of the disk-shaped cutter, and at least the outer peripheral portion of the outer peripheral surface of the cutter, which is not the convex processed portion, is chamfered so as to become lower toward the recessed surface. It is a manufacturing method of a grid for a storage battery, which is characterized by using a disk-shaped cutter.

In a second aspect of the present invention, the chamfered disc-shaped cutter is chamfered between the outer peripheral surface thereof and the side face of the disc-shaped cutter forming a recess, and the chamfered portion is provided with a flat or curved portion. The method for manufacturing a storage battery grid according to claim 1, wherein the cutter is used.

A third aspect of the present invention is a storage battery including the storage battery grid manufactured by the method according to claim 1 or 2.

[0010]

BEST MODE FOR CARRYING OUT THE INVENTION The inventors of the present invention, as a method for suppressing the decrease in strength and local corrosion due to the occurrence of cracks in the above-mentioned nodal portions of the lattice, have at least a convex-shaped processing of a disk-shaped cutter. It has been found that the outer peripheral surface which is not a part is chamfered so as to be lowered in the direction of the recesses which are alternately provided on both side walls in the thickness direction. Further, it has been found that if chamfering is further provided on the ridge line portion between the lower side of the chamfered portion and the side surface of the cutter to provide a flat or curved portion, it is effective in improving strength by suppressing cracks and suppressing local corrosion. That is, on the outermost peripheral surface provided with the concave portion,
For the surface of the sheet material when passing the sheet material,
A certain inclination is provided on the outermost peripheral surface of the cutter so that the outermost peripheral surface that is substantially parallel to the sheet material is eliminated.
As is clear from the comparison between FIG. 3 and FIGS.
In the conventional method shown in FIG. 4, excessive stress is applied to the knot portion of the sheet material, whereas in the present invention shown in FIGS. 4 to 6, the stress applied to the knot portion of the sheet material is small.
Therefore, it has been found that if the above-mentioned shape is adopted, the strength of the knot portion is improved and the local corrosion is suppressed regardless of the shape of the other portion of the cutter.

[0011]

[Example] A method for manufacturing an expanded lattice will be described.

Plural parallel slits are formed intermittently along the longitudinal direction of the lead alloy sheet in a zigzag pattern (FIG. 1), and then expanded to a predetermined size in the width direction to form a mesh portion. Were formed (Fig. 2).

After filling the lead grid produced by the above method with an active material, it was aged and dried to obtain a positive electrode plate. A lead acid battery (55D23 type) for automobiles was produced by combining this positive electrode plate, a negative electrode plate by a conventional method and a separator mainly composed of microporous polyethylene. A battery was prepared by injecting dilute sulfuric acid of a predetermined specific gravity and a predetermined amount into this battery for chemical conversion.

This time, the angle θ (FIG. 4) formed by the outer peripheral surface of the disk-shaped cutter, which is not the convex processed portion, and the side wall is 90 to 60.
Regarding a battery using a grid produced by using a cutter that has been changed to up to 30 °, and a grid produced by using a cutter having various flat and curved surfaces by chamfering between the outer peripheral surface and the side wall provided with a recess , JIS standard (D5301) light load life test was conducted in the gas phase at 75 ° C. After the end of the life test, a battery disassembly study was conducted. In addition, the ratio of breakage points due to cracking at the knot was investigated (Table 1).

[0015]

[Table 1]

[0016]

From the results shown in Table 1, in the expanded lattice body using the disc-shaped cutter according to the present invention, the angle of the flat portion is the same as that of the conventional No. Compared with No. 1, the fracture rate of the knot was suppressed. Along with that, it was found that the 75 ° C SAE life performance was also improved by angling.

[0017]

[Brief description of drawings]

FIG. 1 is a diagram showing a general rotary-type expanding process.

FIG. 2 is a diagram showing a state in which slits are formed in an alloy sheet and an initial state of expansion in a width direction by a general rotary expanding process.

FIG. 3 is a schematic diagram showing a cross-sectional shape of a plane that passes through the center of a disk of a cutter and is perpendicular to a side surface when forming a knot portion on an alloy sheet with a conventional blade.

FIG. 4 is a schematic diagram showing a cross-sectional shape of a plane that passes through the center of a disk of a cutter and is perpendicular to a side surface when forming a knot on an alloy sheet with the blade of the present invention.

FIG. 5 is a schematic view showing a cross-sectional shape of a plane that passes through the center of a disk of a cutter and is perpendicular to a side surface when forming a knot portion on an alloy sheet with the blade of the present invention.

FIG. 6 is a schematic view showing a cross-sectional shape of a plane that passes through the center of a disk of a cutter and is perpendicular to a side surface when forming a knot on an alloy sheet with the blade of the present invention.

[Explanation of symbols]

1 disk-shaped cutter 2 alloy sheet 3 Side wall 4 recess 5 outer peripheral surface 6 Alloy sheet nodule 7 Crack occurrence area 8 Ridge line between the outer peripheral surface and the side surface forming the recess 9 Chamfered flat surface 10 curved surface 11 Convex processing part

Claims (3)

[Claims] 1. A plurality of parallel slits are formed so as to form a zigzag pattern along the traveling direction of the alloy sheet, and a line portion formed by the slits adjacent to each other in the alloy sheet width direction is provided in both front and back directions from the alloy sheet surface. Alternately plastically deformed into a convex shape, a flat area formed by a non-slit portion is formed so as to be a knot portion of the convex line portion, and a mesh portion is formed by expanding this alloy sheet in the width direction. In the method for manufacturing a storage battery grid body used as a grid body, the zigzag slit is a roll formed by laminating disk-shaped cutters having convex processing portions protruding at equal intervals from the circumference thereof. It is formed by passing an alloy sheet through a pair of rolls facing each other, and between the convex-shaped processing portions, concave portions are alternately provided in the thickness direction on both side surfaces of a disk-shaped cutter corresponding to the knot portion. In both cases, a disk-shaped cutter is used, which is characterized by using a disk-shaped cutter in which at least the outer peripheral portion of the outer peripheral surface of the cutter, which is not a convex processed portion, is chamfered so as to become lower toward the surface provided with the respective concave portions. Method. 2. A disk-shaped cutter having a chamfered portion between the outer peripheral surface of the chamfered disk-shaped cutter and the side surface of the disk-shaped cutter forming a recess, and the chamfered portion having a flat or curved surface is used. The method for manufacturing a grid body for a storage battery according to claim 1, wherein: 3. A storage battery provided with the storage battery grid manufactured by the method according to claim 1.