The development of innovative rechargeable batteries with high performance and low cost is necessary for the coming low carbon society. In order to realize all-solid-state batteries as an ultimate goal of energy storage systems, in this project, all-solid-state lithium secondary batteries with high power and high energy density will be developed by employing sulfide glass-based superionic materials as one of the most promising solid electrolytes. The structure and reaction of the solid/solid interface between electrolytes and electrodes will be studied and the processes to fabricate the most efficient interface in the batteries will be investigated.

We propose carbon-neutral (CN) energy cycle as the most practical energy circulation system. The CN cycle employs a Pt-free alkaline type fuel cell for selective oxidation of alcohols to acids. Aiming at materialization of this cycle, highly-selective base-metal catalysts will be developed. Fuels are regenerated by reduction of the waste acids in the system with photocatalytically-generated hydrogen or hydrogen produced in the waste heat utilization system, so that the CN cycle will be an environmental benign circulation system.

In this study, we will try to establish a basement for the development of “all solid-state alkaline fuel cells". These fuel cells can use any metal catalysts; however there are virtually no membranes available at present limiting their practical use. In this study, we will reconsider the traditional ion conduction mechanism, and expect to develop new high OH-ion conductive membranes for these fuel cells. Our goal is to build a global technology platform to accelerate the development of these innovative “all solid-state alkaline fuel cells". High efficiency, low cost due to the possibility of using metals other than platinum as catalyst as well as the prospect of using a variety of fuels will be the key advantages of this new technology.

Research for development of ultra-low loss power devices with novel concept is performed, giving an innovative effect on the reduction of carbon dioxide emission. Diamond semiconductor is taken up as the candidate because of its unique physical properties. Complementary research is performed, including understanding of its unique properties, establishment of device physics using its unique physical properties, and development of the material process and the device fabrication process. The novel ultra-low loss power device will be proposed and fabricated, from which the issues for wide utilization in society is clarified.