Aspects relate to systems and methods for manufacture of a battery pack including a metal case circumscribing an inner volume circumscribed on all but one open side, where the case additionally includes a sealing rim positioned at least partially about the open side, a first component that includes at least two or more sides of the case, and a second component that includes at least one other side of the case, at least a battery module installed within the inner volume of the case, and an inner panel installed within the inner volume, between the case and the at least a battery module. In some aspects, sealing rim, first component, and second component are all joined together by welding.