We have been studying the behavior of electrodes used in advanced secondary batteries and fuel cells currently under development for energy storage applications such as electric vehicles. We have also continued to investigate practical means for improving the performance and lifetimes of these batteries and fuel cells. Systems of current interest include nonaqueous-electrolyte cells with Li electrodes (Li/polymer, Li-ion); and fuel cells that utilize the direct electrooxidation of methanol. We study life-limiting and performance-limiting phenomena under realistic cell operating conditions.