PURPOSE: To make it possible to decrease the thickness of base plate itself, by keeping a bottemed frame on which a solar battery base plate is fixed, inside the base body, on whose rear, storage space for a battery to be charged is formed, and by holding the frame, by means of a guard cover on which lens is formed, between the cover and the base body.

CONSTITUTION: In the center of the rear of a base body 1 made of synthetic resin, storage space to keep batterys 2a, 2b to be charged is formed. On the upper surface of a synthetic resin bottemed frame 4, a solar battery base plate 5, which is formed by growing amorphous semiconductor on a glass base plate, is fitted. Inside of base body 1, the frame 4 which the solar battery base plate 5 fits is kept, and the whole is covered with a guard cover 7 which has ring rib 9 fitting in space 8 between the frame 4 and the base body 1. On this guard cover 7, except a part of it's outer circumference, lens part 10, which has almost the same area as the solar battery base plate 5, is formed.