JPH0443569A - Lead storage battery - Google Patents

Abstract

PURPOSE:To maintain good contact between a plate and an electrolyte, and obtain a lead-acid battery of high capacity by arranging two electrolyte retaining bodies of different sizes in such a way as to bite both sides of the plate. CONSTITUTION:An expanded plate 11 of continuous sheet form filled with active material paste 5 and applied with a lower retainer 10 in such a way as to bite the lower surface thereof, is cut into the plates of the predetermined sizes with a cutting machine 6. Then, an upper retainer 9 larger than the size of a cutout expanded plate 8 is placed on the upper surface thereof, and pressed with a press roller 15, thereby applying the upper retainer 9 in such a way as to bite the upper surface of the plate 8. A sealed lead-acid battery is so constituted that the upper retainer 9 is laid between positive and negative plates 12 and 14, using a plate available from the aforesaid process. According to the aforesaid construction, there occurs no shortcircuit due to the swelling of the active material, and the feed of an electrolyte to each plate becomes easy, thereby obtaining the lead-acid battery of high capacity.

Description

[Detailed description of the invention] Industrial applications The present invention relates to improvements in lead-acid batteries.

Conventional technology Generally speaking, the expanded lattice used for the electrode plates of lead-acid batteries is more easily deformed than the conventional cast lattice body, and the active material is more likely to fall off after the lattice is filled with a paste-like active material. A protective paper is stuck to the surface of the electrode plate to prevent the active material from falling off.

Problems to be Solved by the Invention In lead-acid batteries assembled using the above-mentioned electrode plates, the protective paper consists mainly of valves, so the electrolyte gradually loosens its fibers during charging and discharging. Because of this, a separator is also used. The fibers of the protective paper loosened during charging and discharging remain between the electrode plates and the separator, increasing the internal resistance between the electrode plates, resulting in a problem in which the discharge performance of the lead-acid battery deteriorates.

For this reason, it has been proposed to use an electrolyte holder instead of the protective paper to prevent the active material from falling off the electrode plate after being filled with the active material.

However, if the electrolyte holder is used instead of the protective paper to prevent the active material from falling off, the dimensions of the electrolyte holder will become equal to the electrode plate dimensions as the electrode plate is cut. When a lead-acid battery is made by laminating a group of electrode plates, the active material swells during charge and discharge cycles, causing a short circuit between the positive and negative electrode plates, leading to the end of the battery's lifespan.

Means for Solving the Problems In order to solve the above-mentioned problems, the present invention uses an electrode plate in which two electrolyte holders of different sizes are arranged so as to bite into the front and back surfaces of the electrode plate. The electrolyte holder disposed on one surface of the electrode plate has the same dimensions as the electrode plate,
The electrolyte holder on the opposing surface is characterized in that it is larger than the electrode plate.

Since one of the electrolyte holders arranged on the working electrode plate surface is larger than the electrode plate size, an electrode plate group can be formed by simply overlapping the positive and negative electrode plates covered with the electrolyte holder, and During charge/discharge cycles of lead-acid batteries, short circuits due to swelling of the active material can be prevented. In addition, since the electrode plate and the electrolyte holder are in close contact with each other in a wedged state, contact with the electrolyte is improved, resulting in a high capacity.

Example An embodiment of the present invention will be described.

Using an apparatus for producing electrode plates for lead-acid batteries as shown in Figure 2,
A continuous sheet-like expanded lattice 3 is made from a lead sheet 2 using an expander 1, and a continuous sheet-like lower retainer 10 as an electrolyte holder is present between the expanded lattice 3 and the filling belt 7. The active material paste 5 is filled into the expanded grid 3 from the hopper 4.

Next, the active material paste 5 is filled into the lower retainer 10.
A continuous sheet-like expanded electrode plate 11 pasted with the electrodes biting in is cut into predetermined electrode plate dimensions by a cutting machine 6,
Next, from the dimensions of the cut expanded electrode plate 80, 1.
An upper retainer 9 serving as an electrolyte holder that is 0.5 times larger is placed on the upper surface of the expanded electrode plate 8, and a press roller 1 is placed on top of the expanded electrode plate 8.
5, the upper retainer 9 was attached to the expanded electrode plate 8 in a biting state.

A sealed lead-acid battery (4Ah, 2V) was made from the electrode plates made in this way, with the structure shown in Figure 1, in which the upper retainer 9 was placed between the positive electrode plate 12 and the negative electrode plate 4. . In the life evaluation test of product A of the present invention, discharge was IA for 2 hours; charge was 0.
．． 4A, 0.6h, and for comparison, conventional product B (using a cast lattice and the electrode plates and retainer are not in close contact with each other) was used as a sealed lead-acid battery of the same shape as the product of the present invention. Comparative product C (in which the retainer in the electrode plate group has the same size as the electrode plate size and is present in a biting state) was prepared and subjected to the same life evaluation test. the result,
As shown in FIG. 3, the product of the present invention had the longest life. Comparative product C, in which the retainer in the electrode plate group has the same size as the electrode plate size and the retainer is in a biting state, is the product A of the present invention.
Similarly, it had a high initial capacity, but the active material swelled during the cycle and short-circuited, leading to the end of its life.

Effect of the invention The effects of the present invention are as follows.

1) By using an electrolyte holder instead of a protective paper to prevent the active material from falling off, the electrolyte can be easily supplied to each electrode plate, resulting in a high capacity.

2) Short circuits caused by swelling of the active material during charge/discharge cycles can be prevented.

[Brief explanation of the drawing]

FIG. 1 is a sectional view of a sealed lead-acid battery according to an embodiment of the present invention, FIG. 2 is an explanatory diagram of an electrode plate manufacturing apparatus according to an embodiment of the present invention, and FIG. 3 is a diagram showing cycle characteristics. FIG. 1 is an expanding processing device, 2 is a lead sheet, 3 is an expanded grid, 4 is a hopper, 5 is an active material paste, 6 is a cutting machine, 7 is a filling belt, 8 is an expanded electrode plate, 9 is an upper retainer, IO is a lower retainer , 11 is a continuous sheet-like expanded electrode plate, 12 is a positive electrode plate, 13 is a battery case, 1
4 is a negative electrode plate, 15 is a press roller

Claims (3)

[Claims] (1) A lead-acid battery using an electrode plate in which two electrolyte holders of different sizes are placed on the front and back surfaces of the electrode plate, respectively, and are arranged on one side of the electrode plate. A lead-acid battery characterized in that the electrolyte holder has the same dimensions as the electrode plates, and the electrolyte holder on the opposing surface is larger than the electrode plates. (2) The lead-acid battery according to claim (1), wherein the electrolyte holder, which is larger in size than the electrode plates, is disposed between the different electrode plates. (3) The lead-acid battery according to claim (1), wherein the electrode plate is filled with an active material using an expanded lattice.