A battery pack includes a bare cell including an electrode assembly arranged within a can having an opening that is sealed by a cap plate, a protective circuit module (PCM) arranged on the cap plate, a lead member connecting the PCM to the cap plate; a coupling member inserted into the cap plate and coupled to the lead member. The coupling member is made out of a different material than that of the cap plate, each of the coupling member and the lead member include nickel. By including such a coupling member, the strength and durability of the weld connecting the cap plate to the PCM is improved and the contact resistance is lowered.