One in 85 UK electric vehicles shows battery cell imbalance that may cut range and charging performance

Diagnostic tests of more than 10,000 used EVs by London battery specialist Generational found approximately one in 85 cars have a cell imbalance exceeding 50 millivolts, with one in 200 showing serious imbalance above 100 millivolts. The median imbalance across the sample was just eight millivolts. With over two million EVs on UK roads, the findings suggest more than 25,000 vehicles could be affected by faults that reduce range, slow charging or trigger battery management limits.

Why it matters: Fleet operators and charge point operators need to anticipate that a small but significant share of the UK EV parc may exhibit degraded charging behaviour or reduced utilisation, potentially affecting session duration and site throughput. Early battery diagnostics could become a procurement criterion for second hand fleet acquisitions and inform warranty or maintenance contracts.