Life cycle assessment of lithium nickel cobalt manganese oxide (NCM) batteries for electric passenger vehicles

Abstract

This study evaluated and quantified the life cycle environmental impacts of lithium-ion power batteries (LIBs) for passenger electric vehicles to identify key stages that contribute to the overall environmental burden and to find ways to reduce this burden effectively. Primary data for the assessment were collected onsite from the two Chinese leading LIB suppliers, two leading cathode material producers and two battery recycling corporations from 2017 to 2019. Six environmental impact categories, including primary energy demand (PED), global warming potential (GWP), acidification potential (AP), photochemical oxidant creation potential (POCP), eutrophication potential (EP) and human toxicity potential (HTP), were considered in accordance with the ISO 14040/14044 standards. The results indicate that material preparation stage is the largest contributor to the LIB’s life cycle PED, GWP, AP, POCP, EP and HTP, with the cathode active material, wrought aluminum and electrolytes as the predominant contributors. In the production stage, vacuum drying and coating and drying are the two main processes for all the six impact categories. In the end-of-life stage, waste LIBs recycling could largely reduce the life cycle POCP and HTP. Sensitivity analysis results depict that replacing NCM 622 by NCM 811 as the cathode active material could increase all the six environmental impacts. We hope this study is helpful to reduce the uncertainties associated with the life cycle assessment of LIBs in existing literatures and to identify opportunities to improve the environmental performance of LIBs within the whole life cycle.