Mesoporous Silicon-Based Anodes for High Capacity, High Performance Li-ion Batteries

A new high capacity anode composite based on mesoporous silicon is proposed. By virtue of a structure that resembles a pseudo one-dimensional phase, the active anode material will be able to accommodate significant volume changes expected upon alloying and de-alloying with lithium. The mesoporosity will be created without the aid of a surfactant template using a novel high volume synthetic process. The anode composite based on this material is designed to have a reversible Li-ion capacity exceeding 600 mAh/g or nearly twice that obtainable with graphite anodes; indeed much higher capacities could be practically attainable. Phase I successfully demonstrated the synthesis of this new meso-Si material as well as its high electrochemical activity and rechargeability. An expanded investigation on the development of mesoporous Si-based Li-ion anode is the principal objective in Phase II. The optimum anode will be evaluated in Li-ion cells containing 4V oxide cathodes.