Hybrid Energy Storage Systems for Electric Vehicles: Multi-Source Inverter Topologies

The global interest in Electric Vehicles (EVs) due to their superior performance over the traditional Internal Combustion Engine (ICE) cars is increasing daily and has motivated governments and car manufacturers to spend significant effort in replacing ICE cars with efficient EVs. Batteries as the expensive parts of EVs suffer from challenges such as short life span under high discharge/charge rates, efficiency drop in cold climates, high internal resistance, and low specific power. To mitigate these issues, a complimentary use of these batteries with Ultra-Capacitors (UC) has been highly recommended. This paper surveys the state-of-the-art for both the batteries and UC technologies as energy and power sources for EV applications. In addition, multi-source inverters as a new technology for combining these sources without using DC-DC converters are also reviewed.