PURPOSE: To enable a battery to be preserved for a long period of time by filling a sealed case with electrolyte in such a manner that a space is left in the case, placing electrodes in the space, and making these electrodes to be immersed in the electolyte only in using the battery for making it to discharge.

CONSTITUTION: About two thirds of the entire space of a sealed case 1 made of glass or the like is filled with an electrolyte 2, and the other one third of that is left as a space 3. A positive electrode 4 made of lead peroxide and a negative electrode 5 made of lead, which are tightly fixed to the case 1, are placed in the space 3. A part of each of these electrodes 4 and 5 is made to protrude from the case 1 so that a miniature lamp or the like can be attached to these parts. In using such a battery, the case 1 is reversed so as to make the electrodes 4 and 5 to be immersed in the electrolyte 2 and to make discharge to be carried out, thereby making the miniature lamp or the like to light. Consequently, any self discharge can be prevented, and the battery can be preserved for a long period of time by preventing any contact between the electrodes 4, 5 and the electrolyte 5.