Even though hybrid and plug-in hybrid vehicle do possess certain challenges, energy storage system are something, electric vehicles are facing trouble to be adapted. In conventional batteries, the behaviour of pulsed power and energy content are considered to be the best performance.
Two major issues identified in vehicle applications are life cycle and abuse tolerance. In the present scenario, in most of the HEVs, nickel metal hydride batteries are used and for PHEVs, lithium-ion batteries.
In some applications, ultra-capacitors are considered to be the major concern with the demand for power. The investigation of the flywheels is also important. The current energy storage is with the limitations of unsatisfied power density and energy density. The life cycles are limited with high cost and potential safety issues.
In my opinion, the future is not just about the metal design bodies but the main fuel or the energy storage system. The vehicle with an efficient and healthy environmental energy storage system with a long-lasting capability to be operable till the long run is something need to be invented or discovered.
Sources:- Hybrid electric vehicles (Principles and applications with practical perspectives) by Chris Mi, M.Abul Masrur and David Wenzhong Gao.