JPH0328785B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a sealed lead-acid battery having a structure in which an electrolyte is contained in a pine-like retainer made of extremely thin glass fibers.

In general, a retainer type lead-acid battery is constructed by assembling an anode plate and a cathode plate via a retainer so that electrolyte is not present anywhere other than in the electrode plates and the retainer, thereby preventing leakage and achieving airtight sealing. Therefore, in order to make a battery with a large capacity, it is necessary to increase the concentration of the electrolytic solution or increase the amount of the electrolyte. Increasing the concentration of sulfuric acid is not desirable in terms of longevity, so it is desirable to increase the amount of liquid.To do this, increase the porosity of the electrode plate so that more electrolyte can be retained in the plate. Otherwise, it is necessary to increase the thickness of the retainer. However, increasing the porosity of the electrode plate is undesirable, especially for the anode plate, since it shortens its life. Therefore, in order to increase the capacity, it is necessary to increase the thickness of the retainer to hold more electrolyte, but on the other hand, as the thickness increases, the discharge voltage characteristics deteriorate.

An object of the present invention is to provide a retainer type lead-acid battery that eliminates such drawbacks.

The present invention provides a cage type lead-acid battery having one anode plate and two cathode plates, in which one or more through holes are formed on both sides of the anode plate through a low resistance separator, a thin retainer, or a composite material combining these. The present invention is characterized by disposing a cathode plate provided with the above, and further disposing a retainer holding a sufficient amount of electrolyte on the outside of the cathode plate.

Since the amount of liquid in a retainer-type lead-acid battery is limited, the degree of contact between the retainer and the electrode plates has a large effect on the capacity and discharge voltage. For this reason, 15 to 25
It is inserted into the battery case with a load of Kg/dm ² applied. The group structure of the present invention also increases the contact between the electrode plate and the retainer by applying a pressure of about 20 kg/dm ² , and furthermore, the outer retainer of the cathode plate passes through the inner retainer, separator, etc. and the through hole of the cathode plate. Contact. Therefore, the electrolytic solution required during discharge can be sufficiently supplied from the outer retainer through this through hole, and the internal resistance is also small because the distance between the anode plate and the cathode plate is narrow.

Next, embodiments of the present invention will be described.

An electrode plate group is made up of one anode plate 1 with dimensions of 40 x 60 mm and a thickness of 3.5 mm, and two cathode plates 2 with a thickness of 1.4 mm, each having four through holes 3 of 5 x 10 mm on the entire surface. Configure. The cathode plate 2 is placed on both sides of the anode plate 1 via a composite material 4 made of a 0.5 mm thick retainer and a 0.2 mm thick low resistance separator with a specific resistance of 0.0008 Ωcm, and a 1.8 mm outer layer is placed between the composite material 4 and the anode plate 1. A prototype battery with a nominal capacity of 20 Ah was fabricated using a thick retainer 5. 6 is a battery case.

In order to compare the performance of the product of the present invention with conventional products, a battery was assembled using a 2.5 mm thick retainer with the same anode plate as the product of the present invention and a cathode plate with the same dimensions and active material content but without through holes. At the same time, we produced a prototype and conducted performance tests. FIG. 2 shows the voltage change over time between the product of the present invention and the conventional product when discharged with a current of 1.5A. Looking at the voltage 30 minutes after the start of discharge, it was confirmed that the product of the present invention had a higher voltage of 70 mV when discharged at 20°C and 120mV when discharged at 0°C.

As described above, the present invention has great industrial value in that it can supply electrolyte to the electrode plates without reducing battery life or increasing internal resistance, and can improve battery performance. It is a great thing.

[Brief explanation of drawings]

FIG. 1 is a cross-sectional view of essential parts showing one embodiment of the present invention;
FIG. 2 is a curve diagram showing the change in voltage over time when the product of the present invention and the conventional product were discharged at 1.5A. 1 is an anode plate, 2 is a cathode plate, 3 is a through hole, 4 is a composite material, and 5 is a retainer.

Claims (1)

[Claims] 1. In a cage-type lead-acid battery consisting of one anode plate and two cathode plates, one or more through holes are provided on both sides of the anode plate through a low-resistance separator, a thin retainer, or a composite material combining these. A retainer-type lead-acid battery characterized by having a cathode plate arranged with a cylindrical shape and a retainer arranged outside the cathode plate.