Second Life EV Batteries: Technical Evaluation, Design Framework, and Case Analysis

As the global adoption of Electric Vehicles (EVs) surges, efficient management of retired EV batteries is becoming vital. Second-life Batteries (SLBs), repurposed from retired EV batteries, offer a sustainable energy solution. This paper provides a step-by-step technical assessment, covering battery removal from cars, assessment, and integration into second life applications, focusing on the Nissan Leaf Generation 1. The assessment includes comprehensive testing and presents the results of each test. It outlines the repurposing process, calculating capacity for second life application which was a solar-powered streetlight in this experiment. Economic aspects are explored, with a formula for retired battery purchasing price and the repurposing cost related. The paper also examines State of Health (SOH) degradation in the second life application, showing a decline from an initial 49.17% to 44.75% after 100 days and further to 29.25% after 350 days in the second life application. Factors affecting the degradation such as remaining capacity and internal resistance and their inter-relation were investigated. Challenges in SLB implementation are discussed, along with future recommendations. This study underscores the significance of SLBs in promoting sustainable energy systems amid growing EV usage.