The effect of pollution on the planet earth and the rapid use of fossil fuels provides a strong impulse for the growth and evolution of electric vehicles (EVs). The advancements in Hybrid electric vehicles (HEV) proving the best quick fix towards the severity of the problem on the planet. HEVs not only reduce the emissions but also decreases the fuel cost for the consumer with their improved driving range and dynamic characteristics satisfying environmental regulations. For the extension of the driving range in EVs, multiple energy sources like ultra-capacitor, fuel cells, solar PV are to be interfaced with a battery. This in turn reduces the charging time, which is a significant drawback of EVs. To handle the multiple sources with distinct V–I characteristics, an efficient power electronic circuitry is needed, which can able to provide an efficient power transfer capability between sources and load for the vehicle propulsion. In handling the energy from multiple sources stabilizing at DC bus, the DC-DC converter plays a crucial role. Due to this, in the recent past, the transformation of DC-DC converters from a single input to a multi-input (MIC) has been noticed. The several combinations of integrating sources let on to the new topologies and even more complicated with the configurations. The topology selection imposes more challenges in choosing the best fit for the specific applications. This paper produces a detailed review of the types of EVs, their architectures, merits and demerits. MIC topologies used in EVs with a detailed comparison. A comprehensive study on design rules of MICs, structures and selection procedures of MICs for various applications in detail. This study categorizes MICs based on their characteristics. The significant findings, merits and demerits are also discussed in detail with their suitability.