Plug-in hybrid battery capacity deployed jumps by 38%
Driven by the popularity of range extender vehicles, the average PHEV battery now also sports 40% more kWh than three years ago.
During the first half of 2025, 470.2 GWh of battery capacity was deployed onto roads globally in all newly sold passenger EVs combined, 29% more than the same period last year.
Plug-in hybrids surged ahead, with their combined battery capacity up 38% to 82.8 GWh from January to June. Full electric passenger vehicles followed with a solid 28% increase, reaching 382.6 GWh, while conventional hybrids grew at a steadier 15%, totaling 4.8 GWh.
At the start of 2025, two of the most significant trends in the global EV industry – larger batteries and faster adoption of PHEVs over BEVs – were evening out. BEV and PHEV shipments are now growing at similar rates, with BEVs up 32% (6.1 million units) and PHEVs up 34% (3.4 million units) year-over-year in the first half of 2025. However, while the bulking up of BEV batteries has leveled off, PHEV buyers continue to opt for more onboard kWh. Â
The blistering pace of electrification set by PHEVs was aided by this growth in average battery size, which increased to 24.1 kWh per vehicle, up 3% year on year. In contrast, battery electric vehicles saw a 2% decrease, averaging 62.3 kWh. Conventional hybrids experienced a slight uptick, with a sales-weighted average battery size of 1.3 kWh.
The trend of larger batteries in plug-in hybrids began in earnest in 2022, when their average battery capacity was 17.2 kWh. Today, PHEV batteries are 40% larger, averaging 24.1 kWh. In comparison, BEV batteries have grown by 16%, and HEV batteries by 12% over the same period. As a result, PHEVs now account for 18% of the total battery capacity in newly sold vehicles in the first half of 2025, up from 16% during the same period last year.
The popularity of extended-range EVs or EREVs, in which the combustion engine acts as a charger for the battery only, played a massive role in the bulking up of PHEV batteries.
Shipments of EREVs have doubled annually from 2020 to 2024 and are on track to surpass last year’s 1.4 million registrations in 2025. This year, one in five plug-in hybrid buyers chose an EREV model.
Across the board, EREVs came in at an average of 39.3 kWh over the first six months of 2025, larger than most compact electric vehicles. Removing EREVs from the plug-in category reduces the average battery size of a PHEV to 20.3 kWh.
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