JPH10199537A - Sealed lead storage battery - Google Patents

Abstract

PROBLEM TO BE SOLVED: To enable Pb-Sb based alloy to be used in the positive electrode lattice to eliminate early stage capacity drop of a lead storage battery, owing to such a result that even though Sb is eluated from the grid, it is occluded on positive pole active substance so that Sb eluated quantity into electrolytic liquid and Sb deposit it quantity on a negative electrode plate may be reduced by controlling the positive active material filling thickness in response to Sb quantity and the grid thickness in the positive electrode grid alloy. SOLUTION: When the thickness of a positive active material and a Sb quantity in a positive electrode grid are optimized by using a positive electrode plate in which Sb quantity in the positive electrode grid is in a range from 0.7 to 1.7%, and the total thickness of the positive electrode plate is 110% of the total grid thickness, Sb can be hardly detected on a negative electrode. Hereat, when Sb quantity is more than 1.7%, even if the thickness of active material is increased, the eluated Sb quantity of the negative electrode plate is much. This happens because even though fusing out Sb quantity from the lattice is much, and the thickness of active substance filling is increased, storage of Sb becomes hard. Meanwhile, when Sb quantity is less than 0.7%, the Sb quantity is too small, and water supply is impossible and a drop of the capacity takes place in an early stage, therefore, the Sb quantity is set within a range from 0.7 to 1.7%.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to the improvement of the life performance of a sealed lead-acid battery using a Pb-Sb-based alloy grid as a positive grid, and more particularly to an active material of an electrode plate corresponding to the amount of Sb in a grid alloy. The purpose of the present invention is to improve and stabilize the life performance of the sealed lead-acid battery by suppressing the elution of Sb by applying the thickness of the porous material.

[0002]

2. Description of the Related Art Most of sealed lead-acid batteries use a Pb-Ca-based alloy lattice for the positive electrode, and Pb-Sb-based alloys used in liquid batteries have never been used.

[0003] In a battery using a Pb-Ca alloy, the capacity may be rapidly reduced due to the deterioration of the positive electrode active material or the formation of a passive layer at the lattice / active material interface. In that case S
It is well known that the use of the b alloy for the positive electrode grid makes the above-mentioned early deterioration less likely to occur.

[0004]

However, in practice, it has been difficult to apply a Pb-Sb alloy to a positive electrode lattice. The reason is that when an Sb alloy is used for the positive electrode, Sb elutes into the electrolyte during use. The eluted Sb gradually deposits on the negative electrode plate, causing a reduction in the charging efficiency of the negative electrode plate and increasing the occurrence of gas (water decomposition), so that the amount of the electrolytic solution decreases during use of the battery. This is because the rechargeable battery is hardly affected by the liquid reduction by performing water replenishment, but the sealed battery cannot replenish water. Therefore, the use of the Sb grid causes a rapid decrease in capacity.

[0005]

Accordingly, the present invention provides a sealed lead-acid battery using a Pb-Sb-based alloy containing 0.7% or more and 1.7% or less of Sb in a positive electrode grid, wherein the total thickness of the positive electrode plate is reduced. By setting the thickness of the grid to 110% or more, it is intended to solve the problems in the previous term.

DESCRIPTION OF THE PREFERRED EMBODIMENTS An object of the present invention is to apply a Pb-Sb-based alloy lattice to the positive electrode plate of a sealed lead-acid battery to suppress the deterioration of the positive electrode plate and improve the battery life performance. .
We performed various tests and found that by controlling the thickness of the positive electrode active material filling according to the amount of Sb in the positive electrode grid alloy and the grid thickness, even if Sb elutes from the lattice, it is adsorbed on the positive electrode active material. By doing so, it is intended to reduce the elution of Sb into the electrolyte and the amount of Sb deposited on the negative electrode plate.

An embodiment will be described below.

[0007]

Example 1 Sb content was 0.3% (A), 0.7% (B), 1.2% (C),
1.7% (D), 2.2% (E) Pb-Sb-0.25% As-0.2% Sn alloy 2.0mm thick grid, the total thickness of the filled electrode plate is the original grid thickness 100%, 110%, 120%, and 130% of the positive electrode plates were filled with the active material, respectively.
Using a negative electrode plate having a thickness of 3 mm and a mat-shaped glass fiber separator made of fine glass fibers, about 60 Ah (3 hours)
R) A -12 V retainer-type sealed battery was manufactured according to a normal manufacturing method. A sealed battery using a conventional Pb-0.08% Ca-1% Sn lattice was also manufactured.

[0008] These batteries were first measured at 1/3 CA discharge capacity at 30 ° C, and then subjected to a life test of 200 cycles.
The life test was performed under the general conditions of discharging at a temperature of 50 ° C., 80% of the rated current at a 1/3 CA current, and then charging the battery by a constant current-constant voltage method (1/5 CA / 14.4 V × 8 h). The results are shown in FIGS.
Shown in

Although the 1/3 CA discharge capacity did not depend on the lattice alloy composition, it increased slightly as the thickness of the active material increased. With respect to the discharge capacity after the life test (200 cycles), particularly when the amount of Sb in the positive electrode grid according to the present invention is 0.7% or more and 1.7% or less, and the total thickness of the positive electrode plate is The discharge capacity of the battery using the positive electrode having a total thickness of 110% or more was remarkably superior to that of the battery using the conventional Ca alloy lattice. In addition, those with an Sb content as small as 0.3% or exceeding 1.7% had a remarkably small discharge capacity.

[0010] To investigate the cause, the battery was disassembled after the test and the amount of Sb deposited on the negative electrode active material was examined.
In the case where the total thickness of the positive electrode plate was 7% or more and 1.7% or less and the total thickness of the positive electrode plate was 110% or more of the total thickness of the lattice, almost no Sb was detected in the negative electrode. In other words, the long life can be achieved in the Sb lattice battery because the thickness of the positive electrode active material and the amount of Sb in the positive lattice are optimized as described above, so that the long life which could not be achieved until now is obtained. It has become possible to achieve this.

When the amount of Sb exceeds 1.7%, the amount of Sb deposited on the negative electrode plate is remarkably large even if the thickness of the filled active material is increased. This is presumably because the amount of Sb eluted from the lattice is too large, and even if the thickness of the active material is slightly increased, Sb cannot be completely absorbed. The reason why the capacity was reduced early when the lattice having the Sb content of 0.3% was used is considered to be that the Sb content was too small and the capacity of the positive electrode plate was reduced quickly due to the same reason as the conventional Ca battery. .

In this test, a test was conducted with a retainer battery, which is a form of a sealed lead battery. However, the same tendency was observed with a gel battery and a granular silica battery.

[0013]

As described above, according to the present invention, Pb-S
In a sealed lead-acid battery using a b-based alloy lattice, the amount of Sb (Sb%) is 0.7 to 1.7%, and the total thickness of the positive electrode plate is 110% or more of the total thickness of the lattice. In this way, Pb-S
The use of b-based alloys makes it possible to eliminate the early decline in capacity of sealed lead-acid batteries with a Pb-Ca-based alloy lattice, and its industrial value is extremely large.

[Brief description of the drawings]

FIG. 1 is a characteristic diagram showing a relationship between a positive electrode active material filling thickness, the amount of Sb in a lattice alloy, and an initial capacity.

FIG. 2 is a characteristic diagram showing a relationship between a positive electrode active material filling thickness, the amount of Sb in a lattice alloy, and a discharge capacity after a life test (200 cycles).

Claims (1)

[Claims] 1. The cathode lattice contains 0.7% or more and 1.7% or less of Sb.
A sealed lead-acid battery using a Pb-Sb-based alloy, wherein the total thickness of the positive electrode plate is at least 110% of the total thickness of the grid.