Y. Musa, O. Tantawi, K. Tantawi, L. Flatt, L. Potter
University of Tennessee at Chattanooga,
United States
Keywords: combustion engines, thermal efficiency, electric vehicles, energy density, lithium-ion batteries
Summary:
electric vehicles experience an all-time peak growth, Internal Combustion Engine (ICE) vehicles continue to make a strong case in range and performance, particularly in extreme low and high weather conditions. Their main drawbacks include their greenhouse effect and their low thermal efficiencies which are in the range 30-43%. Research suggests that electric vehicles excel in the compact and short range vehicle classes even without government subsidies. Their performance, however, decreases as vehicle size class and range increases, making them underperform ICE vehicles even with government subsidies in the large vehicle classes. The main challenge that faces electric vehicles is the extremely low specific energy of current battery technologies compared to that in hydrocarbon fuels, for instance current batteries can store up to 2.5 % of the energy stored in gasoline of similar weight. If current research succeeds in improving ICE efficiencies to the 60% range, they will likely dominate the roads for many decades to come. However, in order for them to completely eliminate any competition from electric vehicles, a revolutionary change in internal combustion engines that is not based on the Carnot cycle is needed, in order to advance their efficiencies to beyond the 80% limit.