Using only a battery as opposed to an Internal Combustion Engine (ICE), these vehicles don’t require assistance from an alternative source of power.
Plug-In Vehicles (PEVs), are simply a sub-set of BEVs but are most commonly referred to as Plug-In Hybrid Vehicles (PHEVs) which are an advanced version of the standard hybrid. They host an ICE engine alongside a chargeable electric motor and can travel further on electric power than that of a regular hybrid vehicle.
It completely depends on your business' electric fleet management requirements. One business may be prepared to take on a full transition to BEVs, whereas another may not be as keen or ready to move from ICE vehicles, so a PHEV fleet would be a better fit in that case.
Ideally, businesses should aim to have an entirely electric vehicle fleet as they are the most sustainable option due to the lack of tailpipe emissions, with a small caveat that BEV production can still cause some emissions, namely from battery production.
Despite this, BEVs are far and away the right choice for businesses looking for a near 100% sustainable fleet.
Alternatively, PHEVs still host an ICE engine, so regardless of their electric capabilities there will always be a considerable amount of tailpipe emissions, but it’s still a more eco-friendly option than a regular ICE vehicle and a great transitional choice for businesses trying electric.
Mild Hybrid Electric Vehicles (MHEV) aren’t too dissimilar to PHEVs or normal hybrids, the only difference being the size of the battery that powers the electric motor; it’s considerably smaller than a PHEV and it doesn't require a plug to charge.
The battery won't interfere with the ICE engine as much, but it can work independently to power less essential vehicle features such as air-conditioning and heating.