JPS6050862A - Positive plate for quick use type lead storage battery - Google Patents

Abstract

PURPOSE:To realize long term storing only through improvement of alloy composition of substrate by filling the lattice type substrate where aluminum of specified amount or more is contained into the Pb-Sb alloy with an active substance. CONSTITUTION:A substrate where 0.01wt% of aluminum is contained to the Pb- Sb alloy is filled with an active substance. For example, the lattice type substrate surface consisting of 2.5% Sb-0.2% Al-Pb alloy is filled with an unformed active substance. Thereafter, it is placed in a forming reservior. Thus, forming is carried out through charging and discharging. It is then washed by water and is dried up to form a pole plate. When aluminum is added to the Pb-Sb alloy, a crystal composition becomes fine and the interface of lattice type substrate and active substance becomes dense. But if amount of addition is under 0.01% aluminum cannot show its full performance. In case aluminum of 1% of more is added, a solid solution is not formed at the interface between Pb-Sb alloy, forming only mechanical mixing. Therefore, desired amount of addition of aluminum is about 0.2-0.8%.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an improvement of an anode plate for a ready-to-use lead-acid battery, by increasing the adhesion between the substrate and the active material, and by densifying the interface between the two. The purpose is to prevent the formation of a passive film during the storage period and improve the ready-to-use storage performance.

Conventional ready-to-use lead-acid battery anode plates have P on the lead alloy lattice substrate surface.
It is obtained by filling a wave-stripe unformed active material made by kneading bO with dilute sulfuric acid, and then chemically converting it, washing with water, and drying.

However, since the anode plate is porous, the sulfuric acid content present on the surface of the plate can be removed by washing with water, but the sulfuric acid content impregnated inside is difficult to remove, and the t- is present. . Therefore, if free sulfuric acid remains in the active material, a self-discharge reaction as shown in the equation below will proceed at the interface between the lead alloy lattice of the electrode plate and the active material, forming a passive film of PbSO4. This resulted in a decrease in ready-to-use storage properties.

PbO2+Pb+2H2SO4→2PbSO4+2H2
Therefore, there has been a demand for an electrode plate that can prevent the sulfuric acid of F-IJ- from penetrating into the interface between the lattice-like substrate and the active material, and can prevent the formation of a passive film at this interface.

As a result of extensive research in response to such demands, the present invention has been developed to increase the adhesion between the electrode plate and the active material, thereby making the interface between the two dense. That is, in the present invention, an active material is filled in a lattice-shaped substrate containing a pb-sb gold alloy At of 0.01 weight percent or more.

In the present invention, when A7 is added to the pb-sb gold alloy, the crystal structure becomes finer and the interface between the lattice-like substrate and the active material becomes denser. Although the amount added was limited to 0.01.1% or more, the above effect cannot be achieved if the amount is less than 0.01%. In addition, when more than 1% of Al is added, no solid solution is formed between the pb-sb gold alloys, and the result is merely mechanical mixing. Therefore, the amount of At added is preferably about 0.2 to 0.8%.

The reason why the substrate is mainly made of a pb-sb gold alloy is that it is used for the purpose of maintenance-free use in lead-acid batteries, and the content of sb is preferably 2.5 to 3.5% by weight.

Next, examples of the present invention will be described.

Example 2. After filling the surface of a lattice-shaped substrate made of 5b-0, 2th At-Pb alloy with an unformed active material, it was placed in a chemical conversion tank and charged and discharged to perform chemical conversion, and then washed with water. The electrode plate of the present invention was obtained by drying.

For comparison with the electrode plate of the present invention, a conventional electrode plate was obtained by chemically forming the surface of a lattice-shaped substrate made of 2.55b-Pb alloy in the same manner as in the example, followed by washing with water and drying.

The thus obtained electrode plate of the present invention and the conventional electrode plate each produced N54.
A 0Z lead-acid battery was assembled and stored at an environmental temperature of 40°C±2°C, and the voltage was measured at the 5th second. The results are shown in the drawings.

As is clear from the drawings, the electrode plate of the present invention could be used as a ready-to-use lead-acid battery with almost no deterioration in its ready-to-use performance even after being stored at 40° C. for 6 months. However, in the case of conventional electrode plates, their ready-to-use performance deteriorated significantly after being stored for six months, making it difficult to use them as ready-to-use lead-acid batteries.

As detailed above, the electrode plate of the present invention can withstand long-term storage simply by improving the alloy composition of the substrate, and is therefore extremely useful for use in ready-to-use lead-acid batteries.

[Brief explanation of the drawing]

The drawing shows a relationship curve diagram between the storage period and the voltage at the 5th second for the electrode plate of the present invention and the conventional electrode plate.

Claims (1)

[Claims] 1. An anode plate for a ready-to-use lead-acid battery, comprising a substrate containing 0.01% by weight or more of pb-sb gold alloy At and filled with an active material.