Cascade Use or Recycle? Secondary Life Planning for Electric Vehicle Batteries in China

China's electric vehicle (EV) industry has experienced rapid growth in recent years, becoming a significant driver of economic and technological advancements.Lifecycle management of EV batteries is now a pressing issue due to environmental concerns.This paper investigates this problem, focusing on the dual strategy of recycling and cascade utilization.Using extensive real-world data, models are estimated to predict EV batteries' performance and lifespan under practical conditions.These capacity degradation models are then applied to forecast the future growth of EV and non-electric vehicle (non-EV) battery volumes and the capacity structure of the battery population.Furthermore, a mathematical model is formulated to describe the flow of batteries in the EV and non-EV population, capturing EV battery transitions through cascade utilization to non-EV uses and to recycling.An optimization problem is then proposed to maximize social utility and to guide decisions on cascade utilization.