Advanced EV and HEV Batteries

Nickel metal hydride is the dominant battery chemistry for hybrid electric vehicles thanks to the success of Toyota's Prius. However, that same success has stimulated interest in both other types of vehicles ranging from micro-hybrids to plug-in hybrids to full electric vehicles, and other types of energy storage devices such as ultracapacitors, Pb-acid, and Li-ion batteries. Li-ion batteries in particular promise advantages over nickel metal hydride batteries in terms of energy and power density, but face challenges in terms of life, cost, abuse tolerance, and low-temperature performance. To address these challenges, a variety of lithium-ion chemistries and cell designs are under development. These developments are being accelerated by the application of computer-aided design tools for batteries that simulate performance, especially thermal behavior, and abuse.