Patent attributes
A plurality of shock-absorbing ribs for protecting batteries are formed on an outer surface of the cover. The plurality of ribs are arranged parallel to each other. The plurality of ribs may be crossed in a lattice-like manner. Shock-absorbing projections each for abutting against a fixing member, engaged with the battery electrode, are formed on an inner surface of the cover. The projection has an annular shape, and a distal end portion of the electrode is received in the projection. A gap between the projection and the fixing member is smaller than a gap between the electrode and the cover. The plurality of ribs and the projections are disposed substantially symmetrically. The plurality of ribs are interconnected by bulge portions.