Make that electrochemical energy storage - batteries. Nov. 2009 Talk at UC Berkeley from the Chemical Sciences and Materials Lab Director at GM. Very knowledgable and speaks well. bits from 1st half - * Li Ion are the major traction batteries currently * Increasing world population major driver to vehicle electrification * Electrified vehicles can use diverse sources of energy * 80% traction efficiency from battery to wheels in EV * note - GM build bus hybrid drive systems (utilized by Gillig in Hayward,Ca) * Cost a challenge in EV's - batteries & electronics are expensive * GM calls Volt and EREV because w/ range, ICE will not come on with flooring pedal * 10 million EREV's (Volts) would only impact grid by 0.9% * EREV40 requires 2.5x power over PHEV40 2nd half more technical with battery electrochemistry - * challenging to estimate battery SOC * using dual negative electrode materials to estimate system state * promising future using higher capacity electrode materials * currently using about 300 mAh/g electrode materials. * Silicon based materials could provide 1500 mAh/g, but challenges to overcome * chemical and mechanical degradation in Li Ion batteries due to solvent reduction and material surface cracking from expansion / contraction (charging/discharging) and a lot more.
