Tsuyoshi Sasaki is a Research Domain Leader of Secondary Batteries at TOYOTA CENTRAL R&D LABS. He received Ph.D. of Materials Science and Engineering from Nagoya University in 2004. He has been working on fundamental research for Li-ion battery cells, electrodes, and materials, especially durability and safety analyses by using electrochemical impedance and in-situ methods, and recently focusing on reuse and recycling of Li-ion batteries. He had also been a guest scientist of the Electrochemistry Laboratory, Paul Scherrer Institute since 2009 to 2012. He has published more than 40 papers and filed more than 150 patents, including the discovery of the memory effect in LiFePO4.