Envia Systems, in partnership with Argonne National Laboratory, proposed to develop and scale-up high energy density lithium ion batteries using nano silicon-carbon composite anodes and high capacity manganese rish layered-layered composite cathodes. Silicon coated carbon nanotubes and fibers and silicon and porous silicon-carbon composite anodes were developed. The novel anode composites targeted a high specific capacity (>1000mAh/g), low irreversible capacity loss (<200mAh/g) and improved cycle life. Envia also developed cathodes with high specific capacity (>250mAh/g) and an irreversible capacity loss that is tailored to match the irreversible capacity loss of the anodes. Integration of both novel anode and cathodes electrodes will take place in the form of approximately 40Ah capacity commercial format pouch cells. Energy density of the commercial pouch cells is expected to be over 400Wh/Kg, which is almost doulbe the energy density of what is available commercially in laptop batteries and three times the energy density of automotive batteries, making widespread adoption of plug-in-hybrid electric vehicles and electric vehicles possible.
