Second-Life Electric Vehicle Batteries for Stationary Energy Storage Applications

Abstract

The rapid growth of electric vehicles (EVs) is accelerating the retirement of lithium-ion batteries, which typically exit mobility use at 70–80% state of health. Although no longer suitable for traction, these packs retain significant capacity for stationary storage, offering both a challenge and an opportunity for sustainable energy systems. This study evaluates the technical, economic, and environmental feasibility of second-life batteries (SLBs) for stationary energy storage in the UK. A mixed-method approach was applied across four objectives: (O1) mapping UK supply channels and developing a metadata intake template; (O2) designing a Python-based diagnostic dashboard to classify and compare batteries; (O3) assessing financial viability using Net Present Value (NPV) and levelized Cost of Storage (LCOS); and (O4) quantifying avoided greenhouse gas (GHG) emissions and material retention against new-battery baselines. Results demonstrate that structured intake improves traceability and safety, while the diagnostic dashboard enables reliable classification of batteries into Good, Marginal, and Bad categories. Techno-economic analysis showed Good-health batteries achieving LCOS values as low as £0.11/kWh and positive NPVs, whereas Bad-health units remained uneconomic. Environmental analysis confirmed significant carbon and material savings, supporting SDGs 7, 9, 12, and 13. This research contributes an integrated framework linking diagnostics, techno-economic modelling, and life cycle assessment, offering stakeholders a practical decision-support tool for scaling SLBs in the UK. This study is among the first to integrate diagnostics, techno-economic modelling, and life cycle assessment into a unified dashboard framework, tailored to the UK context of second-life EV batteries.