Abstract: This invention is to disclose a structure of a battery set comprising a case, a battery body, a holder and a filling body. The case is formed like a clamp shape having an open space inside. The battery body disposed in the open space has a PCB adjacent to an open end of the holder. The holder is disposed on the open end thereof for holding the PCB. The filling body consists of one portion thereof filled in the open space to secure the battery body, and the remaining portions thereof respectively extending outwards to cover the outer side of the case. Therefore, the filling body both secures the holder and the protecting case and seals the open space.