JPH10112324A - Lead-acid battery - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a lead-acid battery with efficient cycle life performance, by injecting specified amount of antimony ion into the surface layer of a grid made of lead-calcium alloy. SOLUTION: A lead-acid battery is produced using as a positive electrode a lead alloy grid which is made by injecting preferably antimony ion of 10<13> -10<15> per 1cm<2> onto the surface layer of the grid made of the lead-calcium alloy. Injecting antimony ion onto the grid surface causes the form or feature of the grid corrosion layer to change, forms passive state layer during discharge, and provides the lead-acid battery with efficient cycle life performance.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an improvement in a grid of a lead storage battery, and more particularly to an improvement in a charge / discharge cycle life performance.

[0002]

2. Description of the Related Art In recent years, there has been an increasing demand for maintenance-free lead-acid batteries, and lead-calcium alloy lattices have been studied instead of conventional lead-antimony alloy lattices.

[0003]

However, when the battery using the lead-calcium alloy lattice is repeatedly charged and discharged deeply, the capacity may be reduced at an early stage, and the early capacity decrease may be caused by the lead-calcium alloy lattice. This is one of the major factors that hinders the practical use of maintenance-free lead-acid storage batteries that use lead.

An object of the present invention is to solve the above problems and to obtain a lead storage battery having excellent cycle life performance.

[0005]

SUMMARY OF THE INVENTION The present invention eliminates the above-mentioned disadvantages when a lead-calcium alloy is used as a lattice, and the gist of the invention is that antimony is added to the surface layer of a lattice composed of a lead-calcium alloy. 10 ¹³ ions per cm ²
An object of the present invention is to provide a lead storage battery having excellent cycle life performance by injecting 10 ¹⁵ pieces.

[0006]

Lead-acid battery according to the embodiment of the present invention is a lead - using lead alloy grid antimony ions were implanted ² per 10 ^{13-10 15} 1cm in the surface layer of the grid consisting of calcium-based alloy. By doing so, early capacity reduction can be prevented, and charge / discharge cycle life performance can be improved.

[0007]

[Example] 1% on the surface layer of a lead-0.1% calcium alloy plate
cm ² per, A: 1 × 10 ¹² pieces, B: 1 × 10 ¹³ pieces, C:
After implanting 1 × 10 ¹⁴ , D: 1 × 10 ¹⁵ , and E: 1 × 10 ¹⁶ antimony ions using an ion implantation apparatus, expand processing is performed, and five kinds of lattices having different ion implantation amounts are obtained. Made a body. Further, for comparison, an expanded grid F without ion implantation was also manufactured, and a battery having a capacity of about 10 Ah was manufactured according to a conventional method using these grids as a positive grid.

The battery thus produced was subjected to a charge / discharge cycle test in which the battery was discharged at 2.5 A to 1.7 V / cell and charged at 120 A of the discharged amount at 1 A. FIG. 1 shows the results of the charge / discharge cycle test. By injecting antimony ions into the surface layer of the lattice as described above, the cycle life performance was improved, and a great effect was obtained particularly when the ion implantation amount was 1 × 10 ¹³ to 1 × 10 ¹⁵ .

The reason that the battery using the lead-calcium alloy is apt to cause early capacity reduction is that the corrosion product of the lattice is very dense and highly reactive, unlike the corrosion product of the lead-antimony alloy lattice. Therefore, it is considered that the corroded layer changes to a passivation layer of lead sulfate during the discharge and hinders the discharge of the active material.However, when antimony ions are implanted into the grid surface, the form of the grid corroded layer and It is considered that the properties were changed, the passivation layer was hardly formed at the time of discharge, and the cycle life performance was improved.

Further, the amount of injected antimony is extremely small as compared with the conventional one added to the lattice, and even if the injected antimony precipitates on the negative electrode, the reduction of the hydrogen overvoltage of the negative electrode does not occur. Absent.

In the embodiment, an example is described in which ions are implanted into the expanded lattice. However, similar effects can be obtained in the case of a cast lattice or a perforated plate lattice.

[0012]

As described above, the use of a lattice in which antimony ions are implanted in the surface layer of the lead-calcium alloy lattice can prevent the early capacity reduction peculiar to the battery using the lead-calcium alloy lattice, and thus the charge / discharge cycle. The industrial value is extremely large because the life performance can be improved.

[Brief description of the drawings]

FIG. 1 is a diagram showing a relationship between an antimony ion implantation amount and a charge / discharge cycle life.

Claims (1)

[Claims] 1. A surface layer of a lattice body made of a lead-calcium alloy is coated with antimony ions in an amount of 10 ¹³ to 10 ¹⁵ per cm ^2.
A lead-acid battery characterized by using a lead alloy grid injected into pieces.