Techno-economic feasibility of retired electric-vehicle batteries repurpose/reuse in second-life applications: A systematic review

In line with the global target in decarbonising the transportation sector and the noticeable increase of new electric vehicles (EV) owners, concerns are raised regarding the expected quantity of Retired EV Batteries (REVB) exposed to the environment when they reach 70–80% of their original capacity. However, there is significant potential for REVB, after deinstallation, to deliver energy for alternative applications such as storing surplus. This systematic review evaluates state-of-art modelling/experimental studies focused on repurposing REVB in second-life applications. Technical and economic viability of REVB repurposing has been confirmed to solve the unreliability of cleaner energy technologies and mitigate the high investment of new storage systems. 40% of included studies considered hybrid systems with PV being a dominant technology where REVB was evaluated to be small-scaled and large storage systems. Additionally, successful attempts were conducted to evaluate REVB performance in providing grid services. It has however, been discovered intensive grid services applications like frequency regulation, was technically challenging due to demanding working requirements. Reviewed studies considered different prices for REVB due to lack of market regulation on REVB resale; similarly, technical parameters, including initial State of Health (SoH) and State of Charge (SoC) constraints were inconsistent due to lack of standardisation.