Patent ID: 8263249

Claim:
A battery cartridge having at least two unit cells disposed therein, the battery cartridge comprising: a plurality of plate-shaped members; at least one rotation part connected to at least two of the plurality of plate-shaped members and disposed in a longitudinal direction of the battery cartridge or in a lateral direction of the battery cartridge, such that the battery cartridge is configured to be folded by a predetermined angle in the longitudinal direction of the battery cartridge or in the lateral direction of the battery cartridge, wherein an edge portion of each of inside surfaces and outside surfaces of the plurality of plate-shaped members protrudes in a direction substantially normal to the each of the inside surfaces and outside surfaces of the plurality of plate-shaped members, wherein middle portions of inside surfaces of the plurality of plate-shaped members are spaced apart from each other in a configuration wherein the battery cartridge is fully folded, wherein an inside portion of the at least one rotation part is protruded with respect to inside surfaces of the at least two of the plurality of plate-shaped members connected thereto and an outside portion of the at least one rotation part is depressed with respect to outside surfaces of the at least two of the plurality of plate-shaped members connected thereto when the battery cartridge is fully unfolded, and wherein the protruded inside portion and the depressed outside portion of the at least one rotation part correspond to each other such that battery cartridges are allowed to be stacked one on another when the battery cartridges are fully unfolded.