Life cycle assessment of lithium-ion batteries and vanadium redox flow batteries-based renewable energy storage systems

Renewable energy has become an important alternative to fossil energy, as it is associated with lower greenhouse gas emissions. However, the intermittent characteristic of renewables urges for energy storage systems, which play an important role in matching the supply and demand of renewable-based electricity. The life cycle of these storage systems results in environmental burdens, which are investigated in this study, focusing on lithium-ion and vanadium flow batteries for renewable energy (solar and wind) storage for grid applications. The impacts are assessed through a life cycle assessment covering the batteries supply phase, their use and end-of-life, with experimental data from test set-ups. The battery composition is investigated in detail as a factor for the final impacts, by comparing two types of cathodes for the lithium-ion battery and the use of recycled electrolyte for the vanadium flow battery. Results indicate that the vanadium-based storage system results in overall lower impacts when manufactured with 100% fresh raw materials, but the impacts are significantly lowered if 50% recycled electrolyte is used, with up to 45.2% lower acidification and 11.1% lower global warming potential. The new lithium-ion battery cathode chemistry results in overall higher impacts, with 41.7% more particulate matter and 52.2% more acidification.