JPH10106547A - Battery electrode plate and its manufacture - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an electrode plate of battery with prolonged lifetime and offer a method for manufacturing such electrode plate with which occurrence of electric shortcircuiting is prevented and the charging efficiency of the battery is enhanced by eliminating the risk of separation of an active material applied to the side face of the edge of each electrode plate. SOLUTION: An active material 22 in viscous liquid state is applied to an electricity collecting plate 21 of a matel material, followed by drying, press rolling, and cutting, and an adhesive substance 23 such as polyvinyl alcohol is applied for preventing separation of the active material 22 from the side face of the edge of each electrode plate where the bonding power is weak relatively because of cutting. Thereby the active material applied to the electrode plate is precluded from separation.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a battery electrode plate and a method of manufacturing the same, and more particularly, to a battery electrode having an adhesive layer so as to prevent the active material applied to the edge of the electrode plate from coming off. The present invention relates to an electrode plate and a method for manufacturing the same.

[0002]

2. Description of the Related Art Referring to FIG. 2, a general battery includes a cylindrical case 1, a charging element 2 provided inside the case 1, and a cap 3 for sealing the case 1.

The charging element 2 is interposed between the anode plate 2a coated with an anode active material, the cathode plate 2c coated with a cathode active material, and the anode plate 2a and the cathode plate 2c for mutual insulation. Including the partition plate 2b.

The anode plate 2a, the partition plate 2b and the cathode plate 2
After the layers c are sequentially stacked, they are wound into a roll and provided in the case 1, and the opening of the case 1 is sealed by the cap 3.

The anode plate 2a and the cathode plate 2c (hereinafter, collectively referred to as "electrodes"), which are components of the battery, are formed by applying a different kind of active material to a metal material.

The conventional electrode plate 10 shown in FIG. 3 includes a current collecting plate 11 made of a metal material and an active material layer 12 applied to the current collecting plate 11.

In the manufacturing process of the electrode plate 10 having such a structure, first, a current collector plate 11 made of a metal material having pores is immersed in an active material in a mucus state to form an active material layer 12, which is then dried and rolled. And electrode plate 1 of desired standard through cutting process
0 is produced.

The active material applied to the current collecting plate 11 includes an active material that contributes to charging and discharging of the battery, and an adhesive mixed to improve the adhesive force between the active materials.

Here, the charging efficiency increases as the mixing ratio of the active material that actually contributes to the electrical charging and discharging is relatively higher than the mixing ratio of the adhesive. The active material is a current collector plate 1
When it is applied to No. 1 and then extruded into a thin plate through a rolling process, its mixing ratio is determined within a range that does not separate from the current collecting plate 11.

However, in the process of cutting the electrode plate 10 into a desired size according to the size of the case, the cut surface and the active material near the cut surface are easily detached, and the adhesive strength of the active material to other parts is reduced. They tend to weaken relatively. Further, an anode plate 2a (FIG. 2) and a cathode plate 2 each coated with a different active material.
c, after cutting, the active material layer 12 applied to the electrode plate 10 is wound between the two electrode plates 10 with a partition plate 2b interposed between the two electrode plates 10 and rolled into a roll. A shear force is applied by the crimping force, and such a shear force is most remarkable on the edge side surface of the electrode plate 10. Therefore, there is a problem that the active material is easily detached from the edge cut surface of the bipolar plate 10 and the detached active material causes an electrical short circuit between the bipolar plates 10.

The electric short circuit caused by the detachment of the active material reduces the charging efficiency and shortens the life of the battery.

[0012]

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned conventional problems, and is intended to prevent the active material applied to the side surface of the edge portion of the electrode plate from coming off, thereby preventing the electric material from coming off. It is an object of the present invention to provide a battery electrode plate capable of preventing a short circuit, improving the charging efficiency of the battery, and extending the life, and a method for manufacturing the same.

[0013]

In order to achieve the above object, an electrode plate of a battery according to the present invention comprises a current collector plate made of a metal material having pores, and an active material layer applied to the current collector plate. And an adhesive layer applied to the side surface of the edge portion of the current collecting plate to prevent the active material from separating.

According to another aspect of the present invention, there is provided a method for manufacturing an electrode plate for a battery, comprising forming an active material layer by applying a viscous liquid active material to a current collector plate made of a metal material having pores. And d) drying the active material so that the active material is fixed to the current collecting plate; rolling the current collecting plate coated with the active material to a predetermined thickness; Cutting to a predetermined width and length, and applying an adhesive material on the active material layer applied to the edge side surface of the cut electrode plate to prevent the active material from separating. And winding the electrode plate to form a charging element.

[0015]

Preferred embodiments of the present invention will be described below with reference to the accompanying drawings.

Referring to FIG. 1, an electrode plate 20 of a battery according to the present invention includes a current collecting plate 21 made of a metal material having pores, an active material layer 22 coated on the current collecting plate 21, and a current collecting plate 21. Active material layer 2 applied on the side surface of the edge
2 includes an adhesive layer 23 applied thereon.

The adhesive layer 23 is applied to prevent the active material applied on the side surface of the edge of the current collector plate 21 from coming off, and is preferably a material having a strong adhesive force. In the present embodiment, polyvinyl alcohol (PVA: polyvinyl alcoho
l) was applied to the active material layer 22 to increase the adhesive strength of the active material.

The electrode plate 2 of the present invention having the above structure
In the manufacture of the battery 21, first, depending on the type of a battery such as a nickel-metal hydride battery or a nickel-metal halide battery, the current collecting plate 21 made of a metal material having pores is used.
To form

Next, an active material layer 22 is formed by applying a viscous active material containing water to the current collecting plate 21.

Next, a current collecting plate 2 coated with an active material
By passing 1 through a dryer, the moisture contained in the active material layer 22 is evaporated, and the active material is fixed to the current collecting plate 21 by the shrinkage force thereby.

Next, after the electrode plate 20 is rolled to a predetermined thickness by a press, the electrode plate 20 is cut into a predetermined size in consideration of the charging capacity.

Next, after the cut electrode plates 20 are stacked in parallel, an adhesive layer 23 such as polyvinyl alcohol is applied to the side surface of the edge of the electrode plate 20. Such an adhesive layer 23 is adsorbed by the active material layer 22 applied to the side surface of the edge of the electrode plate 20 to increase the mutual bonding force of the active material.

Next, the anode plate 2a with the partition plate 2b interposed
(See FIG. 2) and the cathode plate 2c are wound into a roll. At this time,
Although the shearing force is concentrated on the side surface of the edge of the electrode plate 20, the active material layer 22 is maintained by the adhesive layer 23 applied to the side surface of the electrode, thereby preventing the active material from being detached. Preferably, the charging element wound in a roll shape has a volume occupying about 95% of the internal space of the battery case.

[0024]

As described above, according to the present invention, the active material applied to the electrode plate is prevented from being separated in the winding step for winding the manufactured electrode plate into a roll shape, and the electric power of the battery is prevented. The short circuit is prevented, and thus, the charging efficiency of the battery is improved, and the life is extended.

[Brief description of the drawings]

FIG. 1 is a partially cutaway perspective view schematically illustrating an electrode plate of a battery according to an embodiment of the present invention.

FIG. 2 is a schematic exploded perspective view of a general battery.

FIG. 3 is a partially cutaway perspective view schematically illustrating a conventional electrode plate employed in the battery of FIG. 2;

[Explanation of symbols]

 Reference Signs List 20 Battery plate 21 Current collecting plate 22 Active material layer 23 Adhesive layer

Claims (4)

[Claims] A current collector plate made of a metal material having pores; an active material layer applied to the current collector plate; and an active material layer applied to an edge of the current collector plate. An electrode plate for a battery, comprising an adhesive layer which is applied to prevent the active material from separating. 2. The electrode plate according to claim 1, wherein the adhesive layer is made of polyvinyl alcohol. 3. A step of applying an active material in a mucus state to a current collector plate of a metal material having pores to form an active material layer, and drying the active material so that the active material is fixed to the current collector plate. Rolling the current collector plate coated with the active material to a predetermined thickness; cutting the current collector plate to a predetermined width and length; and the cut electrode plate Applying an adhesive material on the active material layer applied to the side surface of the edge to prevent detachment of the active material, and winding the electrode plate to form a charging element. A method of manufacturing a battery electrode plate. 4. The method of claim 3, wherein the adhesive is polyvinyl alcohol.