Battery pack

A battery pack is provided that comprises a battery cell, a first case and a second case coupled to each other to receive the battery cell. The first case comprises a first base plate arranged adjacent a main surface of the battery cell and a first side wall arranged to protrude from the first base plate along an edge portion of the first base plate. The first side wall is arranged adjacent a first side of the battery cell and comprises at least one support portion comprising alternating first and second portions, wherein the first portions are thicker than the second portions.