Patent ID: 7794867

Claim:
A battery apparatus comprising: a case having a width, a thickness, and a length, the case including a main body section and a bottom section, the bottom section including a first surface; a battery cell housed in an inside of the case; a terminal disposed at a corner located between the first surface and a second surface of the case and electrically connected to the battery cell; convex pieces formed projecting outwardly in the width direction at the first surface of both sides in the width direction, the convex pieces extending in the width direction a distance less than the width of the main body section of the case; guide grooves extending in the length direction formed by the convex pieces on both sides of the case in the width direction and opened to at least the second surface; and convex portions projecting outwardly from the side surfaces in the width direction provided in the guide grooves formed by the convex pieces, the convex portions extending in the width direction a distance less than the width of the main body section of the case.