Theme 1: Research and development for oxide-based all-solid-state batteries

 

All-solid-state lithium-ion batteries (LIBs), using nonflammable inorganic solid Li-ion conductor as an electrolyte, is expected as one of the next generation energy storage devices, because its safety and reliability are much superior to present LIB with flammable organic carbonate liquid electrolyte. To realize high performance all solid-state LIBs, our group are developing oxide solid electrolytes with high ionic conductivity and chemical stability against electrode materials and the processing for solid-solid interface between electrode and solid electrolyte in solid state batteries. In addition, we are also working to improve the performance of materials for all-solid-state sodium-ion batteries, which are expected to reduce costs.

Theme 2: Research for advanced high-performance lithium-ion batteries

 

Lithium-ion batteries are being used more and more in the direction of larger size, but due to their high energy density, they may ignite or explode if a problem occurs, and battery safety has become a social problem. Focusing on environment-friendly and inexpensive electrode materials, we will clarify the correlation between the physicochemical properties of the materials and the operating conditions of the battery and the various reaction processes that occur in the battery. We are engaged in research to improve the performance of lithium-ion batteries by clarifying the battery reaction mechanism.

Theme 3: Research on post-lithium-ion batteries (calcium-ion batteries)

 

The development of next-generation secondary batteries (post-lithium-ion batteries) with high safety, low cost, and high energy density to replace lithium-ion batteries has been under consideration. Calcium-ion batteries that use calcium ions (Ca2 +) as charge carriers, which are high valence and have abundant reserves, have the potential to achieve high voltage and large capacity. We are engaged in basic research focusing on the search for electrode materials with high reversibility in charge and discharge reactions.