Critical Review on Powertrain Technologies for Electric Vehicles: Classification, Broadly Adopted Topologies, and Future Challenges

The shift toward electric vehicles (EVs) is inspired by the commitment to mitigate emissions and reliance on fossil fuels, with drive systems at the core of the transformation. EVs replace the traditionally internal combustion engines (ICE) by adopting electric motors powered by batteries. However, there are major issues that may complicate the adoption of EVs including battery limitations, energy density, charging speed, insufficient charging stations, cost, and reliance on critical materials for instance, lithium and cobalt. This paper provides a holistic review about powertrain technologies for EVs discussing the key elements to be considered to ensure efficient charging system, high output power to increase the charging speed, etc. These can be achieved by incorporating cutting-edge technologies in switching power electronic devices (i.e., utilizing silicon-carbide and gallium-nitride), broadly efficient power topologies, leveraging solid-state and silicon anode batteries, thermal management, etc. It also explores several critical technological challenges that impede the performance of EVs, including battery degradation, charging infrastructure, and other related issues along with solutions to address these challenges, such as advancements in battery chemistry, the development of higher energy-density materials, and the implementation of advanced thermal management systems to enhance overall efficiency and longevity. In top of that, this review clearly highlights the classification of the recently adopted power train technologies, broadly adopted converters, as well as future trends on breakthroughs in next-generation solid-state batteries with higher energy density and faster charging, and charging station accessibility improvement. It also offers a constructive insight on integrating some renewable energy sources to enhance EV accessibility and sustainability. Overall, while challenges remain, innovations in batteries, electronics, and infrastructure are paving the way for broader EV adoption.