PURPOSE: To eliminate a charge control circuit, and to absorb the oxygen gas, which is generated at the last stage of charging, efficiently by using a separator, which is mainly made of glass fiber at a constant density, and a negative electrode having the active material in a sealed lead-acid battery.
CONSTITUTION: Power generated in a solar battery 1 is fed to a sealed lead-acid battery 2 through a reverse flow blocking diode 4 to charge the lead-acid battery 2. In the lead-acid battery 2, a separator, which is mainly made of glass fiber at 130-170g/l of apparent density, and a negative electrode having the active material at 3.4-4.1g/c.c. of apparent density and at 540g or more of weight per 1A of output current of the solar battery is used. The oxygen gas generated in a positive electrode at the time of charging is permeated through the separator and diffused in the negative electrode smoothly, and all of the oxygen gas is absorbed efficiently in the negative electrode, and the control of charging by a charge control circuit is unnecessary. Consequently, since the sealing property of the lead-acid battery 2 is not lowered, the life characteristic is improved and the structure is simplified.
ONODA YUKIHIRO
SUGIYAMA HIROSHI
