A battery pack assembly for an electric vehicle includes a plurality of battery modules, each of the plurality of battery modules including a plurality of tubes, each of the plurality of tubes including a plurality of individual battery cells therein, where the plurality of individual battery cells within each of the plurality of tubes are in series configuration; and a pair of end cap assemblies positioned at respective ends of the plurality of tubes, the pair of end cap assemblies securing the plurality of individual battery cells and the plurality of tubes in a tightened position by mechanical pressure; the pair of end cap assemblies including a respective electrical connector for connecting the plurality of individual battery cells to the electric vehicle when the battery pack assembly is in the tightened position.