Comparative life cycle assessment of second- and third-life repurposing versus recycling of electric vehicle batteries.

Rapid electric vehicle uptake has elevated the importance of end-of-life (EoL) management of electric vehicle batteries (EVBs). Due to the high environmental burden of EVB production, the focus should shift from EVB production to EoL management over time. Existing life cycle assessment (LCA) studies on EoL management of EVBs typically treat repurposing and preparation for repurposing as a single generic unit process, limit repurposing to one second-life application, and adopt "ready-to-repurpose" assumptions that overlook inhomogeneity among EVB packs and the performance variability of lithium-ion battery (LIB) modules. These simplifications introduce substantial uncertainty into environmental results and may compromise the technical reliability of repurposed EVBs. To address these gaps, this study develops a system-wide Preparation for Repurposing (P4REP) approach that integrates quality screening, performance compatibility, and module-level disassembly within a consequential LCA of EoL strategies for NMC 622 EVBs. Three scenarios-hydrometallurgical recycling, second-life repurposing in an energy storage system (ESS), and combined second- and third-life repurposing in ESS and uninterruptible power supply (UPS) units-are compared using the basket-of-products/functions approach within an expanded multifunctional system boundary. Sensitivity analyses cover the LIB module conversion rate (80-100%) and the 2023-2050 marginal energy transition. The results indicate that any scenario that applies the P4REP approach for at least one additional life has a consistently lower environmental impact than the recycling scenario. Moreover, the scenario combined second- and third-life repurposing reduced the global warming potential relative to the recycling scenario from 13.85 kg CO2 eq.kWh-1 to -6.83 kg CO2 eq.kWh-1. This lower total GWP impact is mainly associated with the reduced contribution of newly manufactured ESS and UPS provision within the expanded multifunctional system boundary, and is conditional on the basket-of-functions construction, a relatively high LIB modules conversion rate, and the projected 2050 European marginal electricity and heat mixes.