JPH03127464A - Sealed type lead storage battery - Google Patents

Abstract

PURPOSE:To increase the capacity and to extend the service life by making the particle diameter of the filling powder larger in the upper part than in the lower part. CONSTITUTION:In a lead storage battery, a powder mainly of SiO2 is filled at the periphery of an electrode plate group and in the clearances between positive electrode plates and negative electrode plates, and in this case, the powder with the particle diameter 50 to 100mu is filled at the lower part and the powder with the particle diameter 200 to 400mu is filled at the upper part. As a result, the electrolyte can be prevented from forming a layer without reducing the discharge capacity, and thereby, a large size sealed type lead storage battery of a high capacity and a long service life can be obtained.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to an improvement in a sealed lead-acid battery for use in which charging and discharging are repeated.

Conventional technology and its issues Most of the sealed lead-acid batteries currently on the market are of the so-called retainer type, in which the positive and negative electrode plates and a separator mainly composed of fine glass fibers are impregnated and held with an electrolyte. It is something. Although this cage-type sealed lead-acid M battery is comparable in performance to conventional open-type lead-acid batteries, it has the problem of high cost. The reason for the high cost is the use of fine glass fiber separators (hereinafter referred to as glass separators) to impregnate and retain the electrolyte between the electrode plates.
This is because expensive separators with excellent liquid holding capacity such as In order to eliminate this high cost, S
Attempts have been made to use powders made of inorganic oxides such as i026. However, when using powders, battery performance is significantly affected by the particle size of the powder, and the performance The disadvantage is that it is inferior to the retainer type.

For example, if a powder with a small particle size is used, the porosity becomes smaller, which not only reduces the amount of electrolyte retained, but also narrows the passageway required for electrolyte diffusion, so the discharge performance is lower than that of a conventional retainer. This is significantly lower than the formula. In contrast,
If the particles of the powder used are made sufficiently large, the above disadvantages will disappear, but the electrolyte retention capacity will decrease, and repeated deep charging and discharging will cause a difference in the ratio jf5 in the vertical direction of the electrolyte, so-called stratification of the electrolyte. A phenomenon occurs. When a battery is used with a stratified electrolyte, lead sulfate concentrates and accumulates in the lower positive and negative electrode plates exposed to high concentration sulfuric acid, and this sulfur B3'a remains active even after charging. This causes a decrease in battery capacity. As described above, when the above-mentioned powder is used as an electrolyte holder instead of a glass separator, performance comparable to that of conventional retainer batteries could not be obtained.

Means for Solving the Problems The present invention is characterized in that the periphery of a group of electrode plates and the gap between the positive and negative electrode plates are filled with a defining/defining powder, and the positive and negative electrode plates and the powder are filled with an electrolytic solution. The above problem is solved by making the particle size of the powder in the lower part of the battery smaller than that in the upper part of the battery in a lead-acid battery having a structure that absorbs and retains .

Example A retainer type battery according to the present invention was manufactured and tested.

This will be explained in detail below.

OK, I made a group of electrode plates consisting of a paste-type positive electrode plate and a shank plate with a height of 260rr1m, and stored this in a battery case.
Ta. Next, powders containing SiO□ as a main component and having different particle sizes were filled into the eoog in two parts. That is, after filling the lower part of the battery with 300 g of powder having a particle size of 50 to 100 μm, 300 g of powder having a particle size of 200 to 400 μm was filled thereon. After that, a predetermined amount of S sulfuric acid is injected, a safety valve etc. are attached according to the usual method, and the
A retainer type battery A of V-200Ah was obtained. Also,
For comparison, battery B is filled only with powder with a particle size of 200 to 400 μm, battery C is filled with only powder with a particle size of 50 to 100 μm, and a conventional retainer type using a glass separator as an electrolyte holder. A battery was made. Table 1 shows the discharge capacities of these batteries. The values in the table are expressed as a ratio to the discharge field of a conventional retainer type battery.

Although the discharge capacity of battery A according to the present invention is inferior to battery B, which is filled only with powder having a large particle size, it is comparable in both high rate discharge and low rate discharge compared to conventional retainer type batteries. I understand that.

Table 1 On the other hand, regarding life performance, discharge at 10 HR current until the terminal voltage reaches 1.70V, then discharge at 2.35V for 2 hours.
It was evaluated by a charge/discharge cycle test in which the battery was charged at 411 times. Figure 1 shows the change in discharge capacity. From this figure, it can be seen that the capacity change of battery F3 filled only with powder having a large particle size is extremely poor. Discharge capacity is 75% of initial value
Table 2 shows the difference in specific gravity between the electrolyte at the top of the battery and the bottom of the battery at the time when the battery was turned off.The electrolyte was significantly stratified at the battery mouth, which is thought to be the reason for the decrease in life performance. On the other hand, in the battery according to the present invention, there is almost no stratification of the electrolyte, and the life performance is comparable to that of conventional retainer type batteries. Battery A″ according to the invention
C- The reason why the electrolytic solution does not become stratified is that the particle size of the powder that can prevent stratification varies depending on the height of the electrode plate, and if the height is 26OIIll'fi, the particle size of the powder It is necessary to set the height to 50 to 100 μm, but if the height is half that height, stratification of the electrolyte solution can be prevented with powder having a coarser particle size. In other words, powder with a large particle size has a weak ability to hold the electrolyte, but the shorter the battery, the less force the thick sulfuric acid produced during charging will have to flow down. It is thought that stratification can be prevented even with coarse powder depending on the height.

Table 2 Note that in this example, an oxide of I1 element was used as the powder, but even if the powder is an oxide of aluminum, titanium, magnesium, etc., or a mixture thereof,
The effect of the present invention is the same. In addition, in this example, the particle size of the powder filled in the lower part of the battery was 50 to 100 μm.
The particle size of the powder to be filled in the second cell was set to 200 to 400 JZ, but this particle size is determined by the size of the battery, the size of the battery, and the scale of the powder. Furthermore, in this example,
Powder was filled in two stages, but the number of times of filling (number of stages)
It goes without saying that by increasing the number of cells, a battery with higher capacity and longer life can be obtained.

Effects of the Invention As described above, the peripheral part of the electrode plate group and the gap between the positive and n electrode plates are filled with acid-resistant and 1 Ift oxidation powder, and the electrolyte is absorbed and retained by the positive and negative electrode plates and the powder. 3;1 with structure
In storage batteries, by increasing the particle size of the powder to be filled in the upper part of the battery, it is possible to reduce the discharge capacity and prevent the formation of electrolyte without stirring. A large, sealed storage battery with a long life of 3rE' can be obtained at low cost, and its industrial value is enormous.

[Brief explanation of the drawing]

Figure 1 shows Battery A according to the invention and other Battery B. The change in discharge capacity during the life test of D is not shown.

Claims (1)

[Claims] 1. Fill the periphery of the electrode plate group consisting of positive and negative electrode plates and porous separators and the gap between the positive and negative electrode plates with acid- and oxidation-resistant powder, and electrolyze the positive and negative electrode plates and the powder. A sealed lead acid battery having a structure for absorbing and retaining liquid, characterized in that the particle size of the powder in the lower part of the battery is smaller than that in the upper part of the battery.