Patent ID: 8802284

Claim:
A battery pack, comprising: a case; and a bare cell, wherein the battery pack further comprises a screw for combining the case and the bare cell to each other, wherein the screw comprises: a head portion having a screw groove formed in a first surface thereof; a body portion disposed on a second surface of the head portion and comprising a screw thread; and a connection portion disposed between the head portion and the body portion, wherein a thickness of the head portion is within 0.6 to less than 0.7 mm, wherein a ratio of a thickness of the head portion with respect to a height of the body portion is within 1:2.5 to 1:3.5, wherein a pitch of the screw thread is greater than 0.25 and less than or equal to 0.35 mm, and wherein an edge portion of the second surface of the head portion has a curvature radius within 0.05 to 0.1 mm.