Automotive Second-Life Batteries: Challenges and Opportunities

Abstract: (Please note: this webinar will be in Portuguese and is sponsored by PELS TC 7.) The growth of electric vehicles (EVs) is driving an unprecedented increase in lithium-ion battery production, raising concerns regarding sustainability, resource availability, and end-of-life management. Automotive second-life batteries, defined as batteries retired from vehicular use but still retaining significant residual capacity, have emerged as a promising solution to extend battery lifetime and reduce environmental impacts. Typically, EV batteries are considered unsuitable for traction applications when their state of health (SoH) falls below approximately 70–80%, although they may remain viable for less demanding stationary energy storage applications. Notwithstanding their potential, second-life battery deployment faces several technical, economic, and regulatory challenges. Key technical challenges include heterogeneous aging profiles, cell imbalance, uncertain remaining useful life (RUL), safety concerns, and the lack of standardized battery designs. Accurate diagnostics and prognostics, particularly the estimation of state of health, are critical to ensure reliability and safety. From an economic point of view, the costs associated with testing, disassembly, reconfiguration, and certification can significantly affect the competitiveness of second-life solutions when compared to declining prices of new batteries. Conversely, second-life batteries offer opportunities in stationary energy storage applications such as grid support, renewable energy integration, peak shaving, backup power, and microgrids. These applications typically impose lower power and cycling demands, making them well suited to repurposed batteries. When properly managed, second-life systems can reduce total battery lifecycle costs, delay recycling, and contribute to a more circular battery economy. Practical case studies from industries such as mining, oil and gas, and large-scale process plants will provide real-world insight into commissioning challenges, motor-drive integration, fault-handling strategies, and lessons learned from field operation. The session aims to give engineers, researchers, and industry professionals a comprehensive overview of the technological advances that enable safer and more reliable medium-voltage variable-speed drive systems.