*3.4. Plug-In Hybrid Electric Vehicles (PHEVs)*

Plug-in hybrid EVs (PHEVs) have relatively smaller rechargeable batteries than those of BEVs. The idea behind plug-in hybrids is to make short journeys powered by battery capacity. PHEVs are now becoming increasingly common. PHEVs are charged by either plugging into such an electric connection, or by using onboard energy generation. These

vehicles have a limited selection in electric-only mode, and can operate at maximum throttle. PHEVs provide important fuel versatility. Although PHEVs contain a larger battery and a more robust motor compared to HEVs, the overall variety is still quite limited [21]. A plug-in hybrid, from a technical perspective, is basically a large hybrid with extra technology. The main distinction between a full hybrid and a plug-in hybrid (PHEV) is that the full hybrid EV battery is charged entirely by using internal combustion, whereas the plug-in hybrid's expanded traction battery is also charged by using a charging station. This means that these plug-in hybrids can only go about 100 km on battery without any internal combustion engine ignition. In particular for tiny towns and short round-trip commutes, this is a significant advantage. This version also permits the lowest potential CO2 emissions between different hybrid systems. The Chevy Volt, Hyundai Ioniq PH EV, and VW Golf GTE are some examples of PHEVs. Figure 6 shows the architectural diagram of plug-in hybrid electric vehicles.

**Figure 6.** Architectural diagram of plug-in hybrid electric vehicles (PHEVs).

### *3.5. Range Extender Hybrid Electric Vehicles (REHEVs)*

Range extender hybrid EVs are much like hybrid plug-in EVs; however, they are distinct in technology. REHEVs are most often regarded as PHEVs; however, REHEVs are often more powerful than PHEVs. The Chevy Volt is the most excellent example of a REHEV. This is arguably the appropriate choice for those who have experience in the EV market because it has a high all-battery portfolio and is driven by a combustion engine with which people are familiar. Figure 7 shows the architectural diagram of range extender hybrid electric vehicles.

**Figure 7.** Architectural diagram of range extender hybrid electric vehicles (REHEVs).
