Electric vehicles (EVs) face a significant cost barrier to increased sales and widespread adoption. The battery pack is the single most expensive component of an EV. This research focuses on the cell packaging scheme as an opportunity to decrease battery pack cost and improve performance. Traditional battery packs use welded metal tabs or wire bonding between individual cells to provide electrical connection from each cell to an electrical buss, which can be complex and labor intensive to implement. An alternative cell packaging scheme is proposed whereby small cylindrical lithium-ion cells are electrically interconnected without being bonded into one solid unit, offering potential benefits for assembly cost and thermal management. The new cell packaging method uses compressible conductive “interconnects” to form the electrical pathway between cells in a pack. Feasibility of the packaging concept is demonstrated for single cells. A multi-cell interconnect design is then demonstrated on pack of 9 cells. The research presents a thorough characterization of the interconnect material properties and recommendations for continued development of the cell packaging method. Results indicate that the packaging method should be feasible on a scaled-up model.
