JPH10106576A - Sealed lead-acid battery - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prolong the cycle lifetime performance by adding a specified quantity of a strontium compound to the positive electrode active material. SOLUTION: Strontium at 0.001-2.0% in relation to the weight of the positive electrode active material is added to the positive electrode active material. 1/3 CA discharging capacity is nearly equal to the case of additive-free till the added variable of germanium oxide achieves 2%, but when added variable exceeds 2%, lowering of capacity is increased. In the case where a small quantity of Ca is contained in the positive electrode grid, the lifetime is prolonged by adding a large quantity of strontium to the active material. On the other hand, in the case where quantity of Ca contained in the positive electrode grid is increased, the lifetime characteristic is improved by adding a small quantity of strontium. As the strontium compound, strontium sulfate is used, but, sulfide, oxide, and hydride of strontium can be used in place of strontium sulfate, and the nearly the same effect can be obtained.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] The present invention relates to a Pb-C
This is related to the improvement of the life performance of sealed lead-acid batteries using a-based alloy lattices. In particular, the addition of a strontium compound to the cathode active material prevents the deterioration of the cathode active material, thereby improving and stabilizing the life performance of the sealed lead-acid battery. The purpose of this is to achieve the conversion.

[0002]

2. Description of the Related Art There are two types of sealed lead-acid batteries, the most widely used at present, a retainer type battery in which a fine glass mat separator is in contact with positive and negative electrodes, and an electrolytic type which has been used mainly in Europe since ancient times. A gel battery in which the liquid is gelled with colloidal silica, and a granule in which granular silica, which has been recently developed, is filled between the electrodes and around the electrode group, and the silica is impregnated with an electrolytic solution. There is a silica type battery.

[0003]

These sealed batteries often use a Pb-Ca based alloy lattice for the positive electrode. In this case, the cycle life of the conventional battery is a liquid type battery using an Sb alloy lattice for the conventional positive electrode. It is known to be considerably shorter than. One of the causes is deterioration (softening) of the positive electrode active material.
It is.

[0004]

DISCLOSURE OF THE INVENTION The present invention is to prevent the softening of the positive electrode active material of a sealed lead-acid battery and to improve the life performance of the battery.
The strontium compound is added to the positive electrode active material in an amount of 0.01% or more and 2.0% or less based on the weight of the positive electrode active material. More preferably, the strontium addition amount {S (%)-positive electrode active material weight ratio-} Calcium content in ｛C (%)-
A sealed lead-acid battery characterized by being controlled according to the following equation according to the weight ratio of the positive electrode grid alloy-合金.

[0005] -0.225C + 0.0235 <S <-3
7.5C + 4.25

DESCRIPTION OF THE PREFERRED EMBODIMENTS A sealed lead-acid battery according to the present invention
A strontium compound is added to the positive electrode active material of a sealed lead-acid battery using a Pb-Ca-based alloy in the positive electrode lattice at a fixed ratio with respect to the weight of the positive electrode active material. Is limited to a range that satisfies a certain formula according to the amount of calcium. By doing so, the deterioration (softening) of the positive electrode active material is prevented, and the life performance of the sealed lead-acid battery can be significantly improved.

[0006]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below based on an embodiment.

A positive grid made of a Pb-0.1% -1.5% Sn alloy, a positive grid made of a Pb-0.08% Ca-1.5% Sn alloy, and a Pb-0.06% Ca-1. 5
% Sn alloy, a total of three types of cathode grids,
0.001% (C), 0.01% (D), 0.1% by weight of strontium sulfate powder per active material weight during paste paste
(E), a positive electrode plate having a thickness of 2.4 mm filled with a paste containing 0.5% (F), 2% (G), and 5% (H) was produced. From 11 paste-type negative electrode plates having a thickness of 0.7 mm and a fine glass mat separator,
A retainer-type sealed battery of about 60 Ah (3 hR) -12 V was manufactured according to a normal manufacturing method.

A battery using a conventional standard electrode plate to which strontium was not added was also manufactured. These batteries were subjected to predetermined injection and charging according to a conventional method, and subjected to the following tests.

First, a 1/3 CA discharge capacity was measured at 30 ° C., and a life test was performed. Life test at 40 ° C, 1/3
After discharging 80% of the rated current with a CA current, the test was carried out under the general condition that 110% of the discharged amount was charged at a constant current. Relationship between strontium sulfate addition and initial capacity (30 ° C)
FIG. 1 shows the relationship between the amount of strontium sulfate added and the life performance.

The 1/3 CA discharge capacity was almost the same as the case where no strontium sulfate was added up to 2%, irrespective of the composition of the lattice alloy, but when the amount exceeded 2%, the decrease in capacity became large. As for the life performance, when the amount of Ca in the positive electrode lattice was small, the longer the strontium was added to the active material, the longer the life. Conversely, C in the positive grid
When the amount of a was increased, the life performance was improved when a small amount of strontium was added. Compared with the conventional battery without the addition of strontium, the life performance was improved because the amount of Ca (lattice weight ratio) in the positive electrode lattice alloy was C
(%), Amount of strontium in active material (weight ratio of active material)
Is S (%), a case where strontium sulfate in an amount calculated by the following formula was added to the positive electrode active material.

-0.225C + 0.0235 <S <-3
7.5C + 4.25 For some time, batteries using a grid in which strontium was added to the positive electrode have been used, but the amount is small, and even if this is dissolved in the active material, it is much smaller than the amount shown in the present invention. That is, the lattice is generally a lattice in which strontium is added to a lattice containing no Ca, and the effect as shown in the present invention has not yet been found.

In this example, strontium sulfate was used as the strontium compound, but as a result of the experiment, there was no significant difference in the effect even when sulfide, oxide or hydroxide was used as the strontium compound.

In this embodiment, a retainer type battery is used as a typical example of the sealed lead-acid battery. However, there is no difference in the effect between the granular silica type battery and the gel type battery.

[0014]

As described above, according to the present invention, Pb is added to the positive electrode.
By adding a strontium compound to the positive electrode active material of a sealed lead-acid battery using a Ca-based alloy lattice, the life performance of the sealed lead-acid battery is significantly improved, and from the viewpoint of practical use of the sealed lead-acid battery, Its industrial value is extremely large.

[Brief description of the drawings]

FIG. 1 is a characteristic diagram showing a relationship between an added amount of strontium sulfate and an initial capacity.

FIG. 2 is a characteristic diagram showing the relationship between the amount of strontium sulfate added and life performance.

Claims (2)

[Claims] 1. A sealed lead-acid battery using a Pb—Ca-based alloy for a positive electrode grid, wherein a strontium compound is used as a positive electrode active material in an amount of 0.001% or more and 2.0% or more per weight of the positive electrode active material.
A sealed lead-acid battery characterized by adding: 2. The amount of strontium added to the positive electrode active material {S (%)-positive electrode active material weight ratio-} depends on the amount of calcium in the positive electrode lattice {C (%)-positive electrode lattice alloy weight ratio-}. The sealed lead-acid battery according to claim 1, wherein the sealed lead-acid battery is controlled according to the following equation: −0.225C + 0.0235 <S <−37.5C +
4.25