| Plug-in hybrid electric vehicles (PHEVs) may become a substantial part of the transportation fleet in a decade or two. This dissertation investigates battery degradation, and how introducing PHEVs may influence the electricity grid, emissions, and petroleum use in the US. It examines the effects of combined driving and vehicle-to-grid (V2G) usage on lifetime performance of commercial Li-ion cells. The testing shows promising capacity fade performance: more than 95% of the original cell capacity remains after thousands of driving days. Statistical analyses indicate that rapid vehicle motive cycling degraded the cells more than slower, V2G galvanostatic cycling. These data are used to examine the potential economic implications of using vehicle batteries to store grid electricity generated at off-peak hours for off-vehicle use during peak hours. The maximum annual profit with perfect market information and no battery degradation cost ranged from ∼US... |