Mitsubishi Falls Behind: Study Reveals the Fastest-Aging Plug-In Hybrids

Germany’s largest automobile club, ADAC, has released a study showing that plug-in hybrid batteries don’t all age the same — their lifespan depends heavily on the manufacturer and how the car is used. Working together with the Austrian company Aviloo, the researchers analyzed more than 28,500 battery health (SoH) readings across vehicles from six major brands.

Mercedes-Benz models came out on top, showing the slowest loss of capacity over time. Volkswagen and BMW hybrids performed within expected limits, though there were a few outliers. Ford’s plug-in hybrids tend to lose capacity more quickly at first, but the process levels off as the car ages. Mitsubishi, however, ranked last — its batteries showed signs of wear much earlier than competitors’.

ADAC advises anyone buying a used plug-in hybrid to check the battery’s condition before making a deal. For vehicles with around 31,000 miles (50,000 km) on the odometer, the state of health (SoH) should be at least 92%, while cars with 124,000 miles (200,000 km) should still maintain 80% or higher. The club also recommends avoiding full charges — keeping the battery between 20% and 80% can significantly extend its life.

According to ADAC experts, those who frequently drive in electric mode might be better off with a modern all-electric vehicle, which requires fewer charging cycles and generally offers a longer service life.