Advanced materials for next generation high energy and power nickel-metal hydride portable batteries

Nickel-metal hydride batteries are in high volume commercial production for mass market portable applications due to an excellent cost to performance ratio, application to a versatile product mix and environmental acceptability. Ovonic Battery Company Inc. (OBC) a subsidiary of Energy Conversion Devices Inc. (ECD) has established the dominant position in Ni-MH batteries by establishing a fundamental patent portfolio, a network of licensees and business affiliates, and continued product improvement based upon its atomic engineering approach. The largest opportunities for Ni-MH market growth are portable power tools, EV, HEV and fuel cell electric vehicles. These applications benefit from improvements in specific energy, cycle life, high temperature performance, activation/formation, and in particular specific power. Advances in materials technology have enabled performance improvements in specific energy (100 Wh/kg), specific power (1000 W/kg), high temperature operation, charge retention, cycle life and voltage stability. While electrode configuration and packaging are important factors in cell design, at the core of next generation Ni-MH technology are the continuing fundamental improvements to the metal hydride and nickel hydroxide active materials. In this paper, advances in performance, applications and cost reduction are discussed with particular emphasis on the improved proprietary metal hydride and nickel hydroxide materials that make such advances possible.