JPH07142081A - Retainer type sealed lead-acid battery - Google Patents

Abstract

PURPOSE:To improve trickle service life performance by forming a foaming resin layer having an average hole diameter larger than the average hole diameter of a separator in the cover reverse space of a storage battery, and absorbing and holding water or dilute sulfuric acid having specific gravity not more than specific gravity of electrolyte in a charging condition. CONSTITUTION:Glass fiber having the average diameter of 1mum and porosity of about 94% and the thickness of 1.5mm under the load of 20kg/dm<2> is used as a separator. The separator is combined with a positive electrode plate and a negative electrode plate, and a 2V battery is manufactured. A foaming resin layer 2 having an average hole diameter larger than the average hole diameter of the separator is formed in the cover reverse space of an upper part. Next, after water or dilute sulfuric acid having specific gravity of 1.05(20 deg.C) is absorbed and held in the resin layer 2, dilute sulfuric acid having specific gravity of 1.32(20 deg.C) is injected into a plate group 3.

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 retainer type sealed lead acid battery.

[0002]

2. Description of the Related Art There are two types of sealed lead-acid batteries, a retainer type and a gel type, which use a so-called oxygen cycle in which oxygen gas generated during battery charging is absorbed by a negative electrode plate. The formula is used.

The retainer type is a mat-like separator (glass separator) made of fine glass fibers inserted between a positive electrode plate and a negative electrode plate, which holds a sulfuric acid electrolyte necessary for charging and discharging and separates both electrodes. Is a method of performing. The retainer type has the advantages of no maintenance, no leakage, position-free, etc., and in recent years it has been used for portable devices, cordless devices, backup power sources for computers, large stationary batteries, and for starting the engine of automobiles. Has become.

[0004]

However, in the sealed lead-acid battery, when the overcharge or the use atmosphere is 40 ° C. or higher, the water content of the electrolytic solution permeates as water vapor, so that the electrolytic solution is gradually removed. Decrease to. For this reason, there is a problem that the electrolytic solution in the separator decreases and the IR loss increases.
Therefore, especially at the time of high-rate discharge such as UPS application, the performance may be significantly reduced.

In order to prevent this problem, it is sufficient to make the electrolyte excessively exist from the beginning, but this will destroy the position-free characteristic of the retainer type sealed lead acid battery, and is not a sufficient solution. I'm sorry.

The present invention has been made to solve the above problems, and an object of the present invention is to reduce IR loss caused by electrolyte reduction due to overcharge or water vapor transmission, An object of the present invention is to provide a retainer-type sealed lead-acid battery excellent in high rate discharge performance at high temperature.

[0007]

Therefore, in the present invention, an open-cell body having an average pore size larger than the average pore size of the separator is arranged in the space behind the lid of the storage battery, and the diluted sulfuric acid having a specific gravity equal to or lower than the specific gravity of the electrolytic solution in a charged state. Alternatively, the container is a closed-type lead-acid battery of a closed type that absorbs and retains water, and in particular, the open-cell body is made of a foaming resin and the average pore size of the open-cell body is 20 to 100 μm.
By setting m, the conventional problems are solved.

[0008]

[Function] As the trickle life test progresses, water vapor permeates through the battery case wall to the outside due to water vapor permeation.
When an open-cell body with an average pore size larger than the average pore size of the separator is placed in the space behind the lid, and when dilute sulfuric acid or water with a specific gravity not higher than the specific gravity of the electrolyte in the charged state is absorbed and retained, the decrease in water content causes the foaming property. It occurs preferentially from the resin layer and is IR in the separator.
It seems that there is no loss and the life performance is improved.

[0009]

The present invention will be described in detail below. The separator has a glass fiber average diameter of about 1 μm and a porosity of about 94%.
The thickness of 1.5 mm under the load of 20 kg / dm ² was used. Combined positive electrode plate, negative electrode plate and separator 2V rated capacity 8
An Ah (20hR) battery was manufactured. 1.5m between pole plates
m.

A foamable resin layer having open cells having an average pore diameter of 1, 20, 50, and 100 μm was formed in the space behind the lid at the top. A schematic sectional view of this storage battery is shown in FIG. In the figure, 1 is a battery case, 2 is a foamable resin layer having open cells formed in the space behind the lid, and 3 is an electrode plate group.

Then, after the dilute sulfuric acid having a specific gravity of 1.05 (20 ° C.) is absorbed and held in the foamable resin layer having open cells, the dilute sulfuric acid having a specific gravity of 1.32 (20 ° C.) is applied to the battery electrode plate group. It was injected. The dilute sulfuric acid injection amount was the same as the electrolytic amount of the conventional product. The liquid volume absorbed and held in the foamable resin layer having open cells was about 11% of the volume of the injected electrolyte of the conventional product. Also, a similar product was manufactured except that water was absorbed and retained instead of dilute sulfuric acid having a specific gravity of 1.05 (20 ° C.).

The storage batteries were subjected to a trickle life test. The test conditions were a voltage of 2.3 V / in a constant temperature bath of 40 ° C.
Trickle charge was performed in the cell, and discharge was performed every 3 months by constant power discharge of 50 W until the final voltage reached 1.65 V / cell, and the discharge duration time was measured.

FIG. 2 shows the result when a foamable resin layer having an average pore diameter of 100 μm was formed. In this figure, the battery No. 1 is a conventional product, and battery No. 1 2 is water, battery No. No. 3 is a case of using dilute sulfuric acid having a specific gravity of 1.05 (20 ° C.).
Battery No. Both Nos. 2 and 3 were superior in trickle life performance to the conventional ones. This tendency is that the average pore size is 2
When the average pore diameter was 1 μm, which was smaller than the average pore diameter of the separator, no difference occurred.

The reason for this is that, as the trickle life test progresses, moisture permeates through the wall of the battery due to water vapor permeation to the outside, but in the space behind the lid, the open-cell body having an average pore size larger than the average pore size of the separator. Is placed, and when dilute sulfuric acid or water having a specific gravity not higher than the specific gravity of the electrolytic solution in a charged state is absorbed and retained, a decrease in water occurs preferentially from the foamable resin layer, and IR loss occurs in the separator. No, it seems that the life performance was excellent.

In this embodiment, the open-cell body made of the expandable resin layer is used, but the present invention is not limited to this, and a ceramic porous body or the like can be used.

[0016]

As described in detail above, according to the present invention, an open-cell body having an average pore size larger than the average pore size of the separator is disposed in the space behind the lid of the storage battery, and the diluted sulfuric acid having a specific gravity not higher than the specific gravity of the electrolyte in the charged state is provided. Alternatively, the present invention relates to a retainer-type sealed lead-acid battery characterized by absorbing and retaining water, in particular, the open-cell body is made of a foaming resin, and the average pore size of the open-cell body is 20 to 100 μm. is there. According to this, the decrease in water content during trickle charge / discharge occurs preferentially from the open-celled body portion, so that the IR loss in the separator portion due to insufficient electrolyte solution is reduced. Therefore, it is possible to provide a retainer-type sealed lead-acid battery having good trickle life performance.

[Brief description of drawings]

FIG. 1 is a schematic cross-sectional view of a main part of a sealed lead-acid battery of the present invention.

FIG. 2 is a 40 ° C. trickle life performance diagram.

[Explanation of symbols]

 1 Battery case 2 Foaming resin with open cells placed on the back of the lid 3 Electrode plate group

Claims (3)

[Claims] 1. An open-cell body having an average pore size larger than the average pore size of the separator is disposed in the space behind the lid of the storage battery to absorb and retain dilute sulfuric acid or water having a specific gravity not higher than the specific gravity of the electrolyte in a charged state. Retainer-type sealed lead acid battery characterized by. 2. The retainer type sealed lead-acid battery according to claim 1, wherein the open-cell body is made of a foamable resin. 3. The average pore diameter of the open-cell body is 20 to 100 μm.
The retainer-type sealed lead-acid battery according to claim 1 or 2, wherein m is m.