BATTERY CASE AND SECONDARY BATTERY COMPRISING SAME

The present invention relates to a battery case having excellent durability and a secondary battery including the same, wherein the battery case according to the present invention includes a first polymer layer, a second polymer layer, and a gas barrier layer disposed between the first polymer layer and the second polymer layer, and includes at least one cup portion curved in one direction, wherein a K value according to Equation (1) is 63.0 or more. K=P/C+50DIn Equation (1),P is a thickness value of the battery case which is measured in µm,C is a depth value of the cup portion which is measured in mm, andD is a ratio of a thickness of the gas barrier layer to a total thickness of the first polymer layer and the second polymer layer.