Following the 2015 COP21 Paris Agreement, the cabinet office decided that Japan will reduce greenhouse gas by 26% compared with 2013 level. In transport sector, 27.4% reduction is targeted against 225 million tons of the emitted CO₂. Therefore, global auto-industries have been finding solutions to solve the global warming. We have been researching on automotive powertrain components such as transmission, battery, motor and its system including engines. Figure below shows a lithium-ion battery modeling diagram to predict its charge/discharge performance. Active material diffusion, current, and overvoltage are generated by electrochemical reactions at electrode surfaces. These internal phenomena are cross-correlated between mechanical and electrochemical engineering. Through the modeling, we are working on efficient hybrid vehicles by optimizing batteries, motors, inverters, and engines. Electric vehicles are supposed to reduce CO₂ however it is increased. By looking at Japan as a whole, its current electrical power generation by thermal power plant increases due to the increase of power consumption by electric vehicles. To consider plug-in hybrid and electric vehicles as solutions to the global warming, the researches must be extended to the optimization in accordance with electrical energy sources. Our researches so far focused on ÅgTank-to-WheelÅh in which the energy source (from tank) is injected into cars and converted to power to rotate tires (wheels). From now on, the studies are extended to ÅgWell-to-TankÅh evaluation system which considers the processes from mining (well) to automobiles. From this viewpoint, we collaborate with researchers of Graduate School of Environment and Energy, for example, Professor Takao Nakagaki whose focuses are on carbon capture, use, and storage (CCS/CCUS) capable of regulating renewable energy in inexpensive coal power plants. He also studies treatment systems of hydrogen generated during Fukushima Daiichi nuclear power plant accident that prevents it from restarting operation. We are expanding researches on safe electric energy generation that suppresses CO₂. Professor Yosuke Nakanishi focuses on an optimal network of decentralized energy resources including renewable energies with consideration on environment and society. To cope with the social and energy demands, we conduct researches on prediction and optimization for uncertainty, planning, investment strategies, system control, and simulation technologies. As above, we will develop the collaborative researches that contribute to smart society through highly efficient plug-in hybrid and electric vehicles with various faculty members.

Li-ion battery performance modeling