JPH10208753A - Electrode for battery and production thereof - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a production method of an electrode for a battery which is not deformed by pressure treatment in the production process. SOLUTION: Tabs 12 are fixed by welding in the side rims of a nickel foam substrate 11 having fine pores and an active material in slurry state is applied to the substrate 11, the pores of the substrate 11 are filled with the active material, and after drying process, the resultant electrode 10 for a battery is pressurized into a prescribed thickness. Notch parts 13 which reach the substrate 11 in the direction at right angles to the longitudinal direction are formed at a plurality of positions in the longitudinal direction in the tabs 12 of the electrode 10. Deformation of the electrode 10 is absorbed by the notch parts 13.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a battery electrode, and more particularly to a paste-type electrode for an alkaline storage battery and a method for producing the same.

[0002]

2. Description of the Related Art In a conventional battery electrode, as shown in FIGS. 6 and 7, an electrode 1 is made of nickel foam along a longitudinal side edge of a nickel foam substrate 2 having a large number of micropores. A tab 3 necessary for connecting the substrate 2 and the electrode terminal is fixed by continuous electric welding or spot electric welding. The tab 3 is made of a strip-shaped nickel plate or a nickel-plated steel plate. Then, the nickel foam substrate 2 is filled with an active material obtained by mixing nickel hydroxide and other powders with a dispersant (adhesive) into the micropores, dried, and then pressed to a predetermined thickness. Electrode 1 for battery by processing
Are formed.

[0003]

In the conventional battery electrode 1 described above, the tabs continuous in a strip shape are welded to the nickel foam substrate 2 before the active material is pressed onto the nickel foam substrate 2. The distortion at the time of pressurization due to the difference in elongation between the tab 3 and the nickel foam substrate 2 filled with the active material has a problem that the battery electrode 1 is deformed due to the constraint of the nickel foam substrate 2 by the tab 3. .

The present invention has been made to solve the above-mentioned problems, and an object of the present invention is to provide a battery electrode without deformation and a method for manufacturing the same.

[0005]

In order to solve the above-mentioned problems of the prior art, a battery electrode according to the present invention is characterized in that a strip-shaped thin plate tab is fixed to a side edge portion of a substrate having minute holes, and a slurry-like plate is formed on the substrate. In a battery electrode coated with an active material, filled and dried, and then pressure-treated to a predetermined thickness, the tabs reach the substrate in a direction orthogonal to the direction at a plurality of locations along a substrate side edge. A notch is formed. In addition, the fixed portion of the tab of the substrate may be a high-density portion by subjecting the substrate to a pressure treatment.

In a method of manufacturing a battery electrode, a tab of a thin strip is fixed to a side edge of a substrate having minute holes, and a plurality of tabs in a direction along the side edge of the substrate are orthogonal to the direction. After forming a notch reaching the substrate in the direction,
A slurry-like active material is applied to the substrate, filled, dried, and then subjected to pressure treatment to a predetermined thickness.

In this manufacturing method, a high-density portion corresponding to the length of a tab of a strip-shaped thin plate is formed under pressure on a side edge of a substrate, and the tab is fixed to the high-density portion. After forming notches reaching the substrate in a direction orthogonal to the direction at a plurality of positions in the direction, the substrate is coated with an active material in the form of slurry, and after drying, pressure treatment is performed to a predetermined thickness. You may.

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, a first embodiment of a battery electrode according to the present invention will be described with reference to a plan view of FIG. 1 and a partial side view of FIG.

The battery electrode 10 includes a nickel foam substrate 11 as a substrate and a tab 12. The nickel foam substrate 11 is rectangular and has a large number of minute holes.

The tab 12 is a strip-shaped thin plate made of a nickel plate or a nickel-plated steel plate, and is fixed to the longitudinal side edge of the nickel foam substrate 11 by continuous electric welding, spot electric welding, or any other fixing means. Have been. The tab 12 is formed with a U-shaped notch 13 that reaches the nickel foam substrate 11 in a direction orthogonal to the longitudinal direction at a plurality of positions in the longitudinal direction (three positions in FIG. 1, every 10 to 50 mm). ing. The nickel foam substrate 11 is coated with an active material in which a dispersing agent is mixed with a powder of nickel hydroxide so as to fill the micropores, and is subjected to a pressure treatment after drying.

Next, a method of manufacturing the battery electrode 10 will be described. First, a strip-shaped thin plate tab 12 is fixed to a longitudinal side edge of a nickel foam substrate 11 by continuous electric welding or spot electric welding. Thereafter, a U-shaped cutout 13 whose tip reaches the nickel foam substrate 11 in a direction orthogonal to the longitudinal direction is punched out at three places in the longitudinal direction of the tab 12 using a press. Then, a slurry-like active material in which a nickel hydroxide powder and a dispersant are mixed or another active material is applied to the nickel foam substrate 11, filled in the micropores, the active material is dried, and then the active material is dried. Is filled with the dried nickel foam substrate 11 using a press, for example, 0.8 mm.
To form a battery electrode 10. In this case, even if the nickel foam substrate 11 on which the tab 12 is fixed and filled with the active material is subjected to a pressure treatment, the nickel foam substrate 11 which is generated by a compressive force for pressing the nickel foam substrate 11 containing the active material and Since the strain energy due to the difference in elongation of the tab 12 is released from the notch 13 that makes the tab 12 discontinuous without being restrained by the tab 12, the tab 12 and the nickel foam substrate 11 filled with the active material are released. The elongation is the same, and the battery electrode 10 is not deformed. The actual battery electrode 10 is cut along the line DD in FIG. 1, and each is used as the battery electrode 10.

FIGS. 3 and 4 show a second embodiment of the battery electrode according to the present invention. The width of the nickel foam substrate 11 is larger than the width of the tab 12 at the side edges in the longitudinal direction. And a high-density portion 14 is formed in which the tissue is densified by pressurization and thinned. The tabs 12 are fixed to the recessed surface of the high-density portion 14 by welding in a reduced thickness, and the tabs 12 are formed at three locations in the longitudinal direction of the tab 12 in a direction perpendicular to the longitudinal direction beyond the high-density portion 14. A U-shaped notch 13 reaching the nickel foam substrate 11 is formed. Further, the nickel foam substrate 11 is filled with an active material obtained by mixing a dispersing agent with a powder of nickel hydroxide, and is dried,
Has been processed.

Next, a method of manufacturing the battery electrode 10 will be described. First, the high-density portion 14 having a width larger than the width of the tab 12 is provided on the side edge portion of the nickel foam substrate 11 in the longitudinal direction.
Is formed by pressing, and then the tab 1
2 is fixed by continuous electric welding or spot electric welding. In this case, since the structure of the high density portion 14 is dense, the weldability of the tab 12 to the nickel foam substrate 11 is improved.

Thereafter, the nickel foam substrate 11 is provided at three positions in the longitudinal direction of the tab 12 in a direction perpendicular to the longitudinal direction.
Is formed by punching a U-shaped notch 13 whose leading end reaches. Then, a slurry active material obtained by mixing nickel hydroxide powder and a dispersant is applied to the nickel foam substrate 11, filled, dried, and then subjected to a pressure treatment to a thickness of 0.8 mm using a press. Thus, the battery electrode 10 is formed.

In this case, since the elongation of the nickel foam substrate 11, the high density portion 14, and the tab 12 are different from each other,
The notch 13 must pass through the tab 12 and the high density portion 14 to reach the nickel foam substrate 11. Therefore, when the nickel foam substrate 11 to which the tabs 12 are fixed and the active material is applied and filled is subjected to a pressure treatment, the strain energy due to the compressive force is released from the notches 13 without being restricted by the tabs 12. The battery electrode 10 is not deformed. The battery electrode 10 is used after being cut along the line EE in FIG.

The nickel foam substrate 1 of the tab 12
The number of welding points for one or the high-density portion 14 may be two as shown in FIGS. 1 and 3, three rows as shown in FIG. 5, or one or more rows. The example of FIG. 5 shows a case where the tabs 12 are welded to the nickel foam substrate 11 in three rows, and the U-shaped and oval-shaped cutouts 13 are formed respectively. And the battery electrode 10 is an FF line,
It is cut by GG line and HH line before use.

[0017]

As described above, in the battery electrode of the present invention, the notch which reaches the substrate in the direction perpendicular to the longitudinal direction is formed in the substrate or the tab fixed to the high density portion formed in the substrate. In addition, the strain energy generated at the time of the pressure treatment is released from the cutout portion, and a battery electrode without deformation can be provided. Then, the method for manufacturing a battery electrode is to form a notch after fixing a tab to a substrate or a high-density portion formed on a side edge portion of the substrate, and then apply, fill and dry an active material. Since the pressure treatment is performed to a predetermined thickness, the strain energy due to the difference in the elongation of the tab and the substrate caused by the compressive force due to the pressure treatment is released from the notch and is not stored in the substrate. This produces effects such as manufacturing without deformation of the electrode.

[Brief description of the drawings]

FIG. 1 is a plan view showing a first embodiment of a battery electrode according to the present invention.

FIG. 2 is a partial side view as viewed from A in FIG. 1;

FIG. 3 is a plan view showing a second embodiment of the battery electrode of the present invention.

FIG. 4 is a partial side view as viewed from B in FIG. 3;

FIG. 5 is an explanatory view showing a welding portion of a tab of a battery electrode.

FIG. 6 is a plan view of a conventional battery electrode.

FIG. 7 is a side view as viewed from C in FIG. 6;

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 Battery electrode 11 Nickel foam board 12 Tab 13 Notch part 14 High density part

Claims (4)

[Claims] 1. A strip-shaped thin plate tab is fixed to a side edge portion of a substrate having fine holes, and a slurry-like active material is applied to the substrate.
In the battery electrode which has been filled and dried and then pressurized to a predetermined thickness, the tab has cutouts reaching the substrate in a direction perpendicular to the direction at a plurality of positions along the substrate side edge. An electrode for a battery, comprising: 2. The battery electrode according to claim 1, wherein the portion of the substrate to which the tab is fixed is a high-density portion obtained by subjecting the substrate to a pressure treatment. 3. A strip-shaped thin plate tab is fixed to a side edge of a substrate having minute holes, and a notch reaching the substrate in a direction orthogonal to the direction at a plurality of locations along the side edge of the substrate. A method for producing a battery electrode, comprising forming a portion, applying and filling a slurry-like active material onto the substrate, drying and pressing the substrate to a predetermined thickness. 4. A high-density portion corresponding to the length of a tab of a strip-shaped thin plate is formed under pressure on a side edge portion of a substrate having minute holes, and the tab is fixed to the high-density portion. After forming notches reaching the substrate in a direction orthogonal to the direction at a plurality of locations, applying a slurry-like active material to the substrate, filling, drying and pressing to a predetermined thickness. A method for producing a battery electrode.