Ultra-high Capacity Anode Materials for Lithium Ion Batteries
B.Z. Jang, A. Zhamu
Nanotek Instruments, Inc., US
Keywords: Anode materials, Nano graphene, nanocomposite, high-capacity
Abstract:Nanotek Instruments, Inc. is seeking partnership and investment opportunities to accelerate the commercialization of a breakthrough lithium-ion battery electrode technology. Through the support of US DOE SBIR Phase-I and Phase-II grants, Nanotek Instruments has developed a new class of electrode materials for the next generation Li-ion batteries. These new electrodes will have the power to extend the mileage range of hybrid electric vehicles (HEVs) and all electric vehicles (EVs) to a range competitive to current internal combustion engines. In addition, this new electrode technology will further enhance the acceptance of Li-ion batteries for electric vehicle use by dramatically improving charge/discharge rates. The DOE support enabled the development of a new class of nano materials now commonly referred to as nano graphene platelets (NGPs) and NGP nanocomposites. An NGP is a nanoscale platelet or sheet composed of one or several layers of graphene plane (or basal plane in a graphite crystal). A graphene plane is a single layer of carbon atoms occupying a 2D hexagonal lattice. Hence, NGPs may be viewed as an atomic-thickness ribbon- or fabric-like reinforcement. Surprisingly, the NGPs exhibit the highest intrinsic strength (130 GPa) and highest thermal conductivity (5,300 W/mK) among existing materials. During the course of this SBIR research, we have discovered that NGP composites containing other select particles exhibit an exceptionally high anode capacity for a long charge-discharge cycle life. We have demonstrated an anode specific capacity of typically > 1,200 mAh/g over 300 cycles, which is 3 times higher than the theoretical limit (372 mAh/g) of the current graphite-based anode material which has an actual capacity of typically 250-350 mAh/g. Several US patent applications have been filed to protect the invented NGP composite-based electrode technologies.