A research group led by Naoki Fukata, a Leader of Nanostructured Semiconducting Materials Group at the International Center for Materials Nanoarchitectonics (MANA), NIMS, and a research group at the Georgia Institute of Technology jointly developed an anode material for lithium (Li)-ion rechargeable batteries by forming nanoparticles made of silicon (Si)-metal composites on metal substrates. The resulting anode material had high capacity—almost twice as high as conventional materials—and a long cycle life. These results will lead to the development of higher-capacity, longer-life anode materials for Li-ion rechargeable batteries this study as a new anode material for Li-ion rechargeable batteries.At present, carbon-based materials are used as anodes for Li-ion rechargeable batteries, and their capacities are up to 370 mAh/g. In theory, their capacities can be increased by more than 10 times to 4,200 mAh/g, provided that pure Si is used as an anode material.