Breakneck pace of range-extender EV growth falls sharply

Under pressure from automakers trying to overcome a major obstacle of car buyers thinking of going electric – range anxiety – battery manufacturers have made rapid strides in packing more punch per kilogram and per liter.

Novel chemistries, fine-tuning tried and tested cathodes and innovation at pack level have all contributed to upping the kWh at the disposal of EV drivers.

Or, all else being equal, by just increasing the overall size.

This trend, steady growth in the battery capacity of the average EV, now seems to have leveled off for full electric vehicles, even going into decline in the final months of 2025. For their plug-in hybrid models, automakers continue to make batteries larger, albeit at much reduced rates than in previous years.

The battery bulge across EV types, which kicked off in earnest in 2022 and accelerated in 2023, was in large part driven by plug-in hybrids (PHEVs) and, more specifically, extended-range EVs (EREVs), in which the combustion engine serves only as a battery charger. 

EREV batteries averaged 39.8 kWh for the first 11 months of last year, larger than most compact vehicles, and a testament to the popularity of EREVs in the large SUV and MPV segment. Strip out EREVs from the plug-in category, and the average battery size of a PHEV falls to 20.7 kWh. Non-range extender plug-ins have also grown rapidly in size. In 2022, PHEVs excluding EREVs had an average battery capacity of just 15.2 kWh.

EREV slowdown

Going into 2026, EREV encroachment on traditional plug-in territory appears to be pulling back.

Sales growth of range extenders (+13% to 1.4 million) are falling behind others in the PHEV segment where sales were up 22% to 5.4 million from January through November 2025 compared to the same period in 2024.

From less than 10% of overall sales in 2022, last year 20% of PHEVs leaving showrooms were propelled by electric motors only, but the share represented a near percentage point drop from 2024.

EREV contribution to battery capacity deployed is also drifting lower. In 2025, EREVs constituted less than 33% of the 166.4 GWh that hit global roads in PHEVs for the first time, down from 37% in 2024.

While average PHEV battery capacity continues to grow year on year, as expected, rates have come down dramatically, declining to 4% through November, narrowing the gap to EREVs, which sported, on average, batteries that are 1% larger than the year before.

BEV comeback

Although much less extreme than the changes in PHEV packs which on average came equipped with 43% larger batteries in 2025 than in 2022, full electric passenger vehicle and minimally electrified conventional hybrids have also been adding capacity.

The battery capacity of BEVs sold in 2025 were 10% bigger than in 2022 while HEV packs grew 11% in size over the same period. 

In 2025, however average BEV cell packs shrank 2% year on year while HEV batteries have settled at the 1.3 kWh mark.

Average battery capacity for all EV types have also risen dramatically since 2022, with a clear uptrend since the start of 2025. For the first 11 months of last year, the average EV battery added more than 1kWh in capacity or 4% to 36.5 kWh.

This is a function of a changing sales mix. Following years of slower growth, BEV sales are now rising faster than those of PHEVs. Compounding the effect, the relative contribution of HEVs is also on a declining path.

Globally, over the first 11 months of 2025 BEV sales were up by 28% year on year to 26.2 million units, compared to a 20% rise for PHEVs to 6.8 million and 11% for HEVs to 6.7 million. Unlike previous years EREVs were a drag on PHEV sales. Non-EREV PHEVs found 22% more buyers versus sales growth of 13% for EREVs.  

Over the first 11 months of 2025, 959.0 GWh of battery capacity was deployed onto roads globally in all newly sold passenger EVs combined, 24% more than the same period last year.

BEVs accounted for 82% of the total, or 783.8 GWh, while the share of PHEVs was 17%, at 166.4 GWh with both types growing at 25% year on year.

Breaking down PHEVs further shows non-EREV total battery capacity deployed jumping by 30% versus a much more sedate pace for range extenders of 14% from January through November 2025 compared to the year before.

That compares to average annual growth rates for EREVs between 2021 and 2024 of more than 115% for both sales and battery capacity deployed.

The share of conventional hybrids remained at 1% thanks to sales weighted average battery sizes that seldom exceed 2 kWh. HEVs recorded 11% year-to-November growth compared to 2024, another reason the average battery size across all EV types is rising.

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