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Lithium ion batteries are superior to NiMH batteries in energy density, but have been excluded from the highest power density applications due to safety and cost limitations. The cathode materials in conventional lithium ion cells are based on metal oxide materials, typically containing nickel or cobalt. These nickel and cobalt based cathode materials are expensive and reactive with the electrolyte. Metal oxides are electronic insulators, which can limit the rate performance of lithium ion cells. The open circuit potential of conventional metal oxide electrodes is relatively high. This limits the charge acceptance rate, since the polarization under high rate charging (> 10C) can exceed the potential limit of the electrolyte. Similarly, the open circuit potential of conventional graphitic anode materials is close to the lithium plating potential which also limits high charge rate acceptance.