Therefore technological innovation is necessary to achieve the target. In this proposal, with a focus on the cathode material of lithium ion battery, a 18650-type cylindrical battery using the lithium excess material which is one of the high capacity cathode material reported recently is designed. The energy density of the battery is calculated and the raw material cost of the battery is estimated. The proposal includes possibilities of energy density increase and raw material cost reduction, and technological challenges in the research of a lithium ion battery using the lithium excess material.