Quantifying the Impact of Battery Degradation in Electric Vehicle Driving through Key Performance Indicators

Abstract

As the Electric Vehicle market grows, understanding the implications of battery degradation on the driving experience is key to fostering trust among users and improving End of Life estimations. This study analyses various road types, charging behaviours and Electric Vehicle models to evaluate the impact of degradation on the performance. Key indicators related to the speed, acceleration, driving times and regenerative capabilities are obtained for different degradation levels to quantify the performance decay. Results show that the impact is highly dependent on the road type and nominal battery capacity. Vehicles with long and medium ranges show a robust performance for common driving conditions. Short-range vehicles perform adequately in urban and rural road conditions, but on highways, speed and acceleration reductions of up to 6.7 km/h and 3.96 (km/h)/s have been observed. The results of this study suggest that degradation should not be a concern for standard driving conditions and mid- and long-range vehicles currently dominate the market. In addition, the results are used to define a functional End of Life criterion based on performance loss, beyond the oversimplified 70–80% State-of-Health threshold, which does not consider individual requirements.

A Method for Assessing the Technical Condition of Traction Batteries Using the Metalog Family of Probability Distributions

“…Scientists are currently working on new methods for balancing battery packs, which are intended to significantly increase the number of fully charged and discharged battery packs. This, of course, reduces the aging process of the batteries and extends their proper operation time in the vehicle [46,47]. Scientists have developed, and engineers have already implemented, in industrial practice, a large number of algorithms and techniques that allow the health of individual cells or entire battery packs to be determined [48].…”