From wastes to resources: the future of residential EV batteries in China through cascade utilization, recycling, and energy storage.

The rapid adoption of residential electric vehicles (EVs) in China presents significant challenges for the sustainable management of end-of-life (EOL) traction batteries. This study developed a scenario-based, province-level model to forecast the temporal and spatial distribution of retired EV batteries, evaluated their second-life energy storage potential, and quantified the economic benefits of recycling under varying electrification rates and regional policy supports. The analysis explicitly incorporated evolving battery chemistries by modeling the shifting shares of high-nickel, lithium iron phosphate (LFP), and emerging solid-state batteries in the EV fleet, and examined their implications for future material composition and recycling value chains. Results indicated that annual battery retirements would peak at 4.25 million tons by 2038, with substantial disparities across provinces. Under rapid electrification and strong policy incentives, regions such as Guangdong and Jiangsu could achieve cumulative economic benefits from battery reuse and recycling exceeding $34 trillion by 2050, representing a 24% increase compared to scenarios with slower EV adoption. Conversely, scenarios featuring slower EV growth but targeted local policies yielded up to 161% higher adaptation rates for second-life batteries in energy storage than uniform national strategies. The increasing dominance of LFP and solid-state chemistries was projected to lower the average material recovery value but enhanced overall safety and sustainability. These findings provided robust quantitative evidence to guide differentiated policy design and infrastructure investment, supporting the development of a circular battery economy critical for China's long-term decarbonization and energy security.