SBIR Phase I: High Capacity Lithium Ion Batteries Using Sponge-like Porous Silicon Anodes

This Small Business Innovation Research Phase I research project will develop unique materials for High Capacity Lithium Ion Batteries Using Sponge-like Porous Silicon Anodes. At the present time, carbon-based materials are utilized as the anode material, which have a theoretical capacity limit for intercalation of Li of 372 mAh/g. The innovation is a breakthrough technology that will lead to an increase in electrical capacity of Li-ion batteries up to an order of magnitude greater than currently possible. An area of active research has been directed towards new materials. In particular, Si has been studied extensively because it has a large theoretical capacity of 4200 mAh/g. However, Si materials have poor performance because with charge-discharge cycling, large accompanying volume changes lead to rapid capacity fade due to loss of mechanical integrity and electronic conductivity. To solve the cycling problem, it is proposed to use a novel sponge-like porous Si, which has a unique morphology with high surface area (for good access of Li ions) and a large pore volume within individual particles (to accommodate the volume change). Increasing Li-ion battery capacity is of paramount importance to the success of a number of applications that affect society on a world-wide basis, such as electric vehicles (to increase mileage range), consumer electronics (compact cell phones and laptop computers), and military operations (lighter and more powerful devices). The worldwide yearly market for Li-ion batteries is expected to be on the order of $40 billion in the next few years.