Quantifying the impact of cell-to-cell inconsistency on electric vehicle battery degradation and utilization

Journal article, 2026

Enhancing utilization rates of battery systems in electric vehicles (EVs) substantially benefits economic efficiency and environmental sustainability. However, cell-to-cell inconsistency remains a critical barrier to fully realizing these advantages, and its system-level impact under real-world EV operation is still poorly quantified. Here we present a dataset containing 116 passenger cars and 17 buses, encompassing operational data spanning more than 3 years and up to 300,000 km per vehicle. Using practical measurements, we estimate individual cell capacity and resistance and construct a diagnostic framework of six metrics capturing variability in cell health, pack capacity retention, lifetime degradation, state-of-charge utilization, power capability and energy utilization. Our analysis reveals substantial performance degradation, including battery health reductions of 6.2% for passenger cars and 7.5% for buses, lifetime shortening by 17.7% and 22.8% and power capability decreases of 12.9% and 15.1%, respectively. Consequently, energy-resource utilization is limited to 80.7% for cars and 72.9% for buses over their operational lifespans. These findings underscore the necessity of consistency control for advancing EV battery technologies.