Difference Between MHEV, HEV, and PHEV: Hybrid Types Explained

MHEVs pair a conventional combustion engine with a small 48V battery and belt-driven starter-generator.

• Electric Driving: CANNOT propel the wheels using electricity alone. The electric unit only assists the petrol/diesel engine during ignition and acceleration.
• Charging: No external plug; recaptures slight kinetic energy only when coasting or braking.
• Battery Capacity: 0.4 to 0.9 kWh.
• Benefit: Smooth start-stop operation and modest 5-10% fuel economy improvement.

HEVs (such as the classic Toyota Prius) integrate an electric motor with an internal combustion engine through a power-split gearbox.

• Electric Driving: Can drive purely on electricity for short bursts (1 to 2 km) at low urban speeds.
• Charging: CANNOT be plugged in. The battery recharges exclusively via regenerative braking and excess engine torque.
• Battery Capacity: 0.9 to 1.8 kWh.
• Benefit: Excellent stop-and-go urban fuel savings without needing a home charger.

PHEVs combine a full-sized electric vehicle powertrain with a petrol or diesel engine in one platform.

• Electric Driving: Offers 50 to 140+ km of genuine zero-emission electric range at full highway speeds (up to 135–140 km/h).
• Charging: Features an external socket (Type 2 AC and increasingly DC CCS2 rapid charging) to connect to domestic wallboxes or public stations.
• Battery Capacity: 15 to 35 kWh high-voltage lithium pack.
• Benefit: Complete zero-emission commuting for daily errands, backed by combustion engine freedom for long road trips with no charging delays. Qualifies for significant European fleet tax breaks (UK BiK, German 0.5% Dienstwagen).