Environmental feasibility of secondary use of electric vehicle lithium-ion batteries in communication base stations

Repurposing spent batteries in communication base stations (CBSs) is a promising option to dispose massive spent lithium-ion batteries (LIBs) from electric vehicles (EVs), yet the environmental feasibility of this practice remains unknown. Life cycle assessment (LCA) is used in this study to compare the environmental impacts of repurposed EV LIBs and lead-acid batteries (LABs) used in conventional energy storage systems (ESSs) of CBSs. The economic-based allocation method is used in the multi-functional system. The LCA results suggest that the manufacturing and reusing stages are the dominant contributors to the environmental impacts of repurposed LIBs, whereas battery recycling can reduce environmental impacts. In addition, the secondary use of EV LIBs results in less environmental impact than the use of LABs in all selected categories, except for metal depletion, which is attributed to the large lead consumption and low energy density of LABs. A sensitivity analysis is conducted to measure the influences of two alternative allocation methods (i.e., cut-off allocation and 50/50 allocation), the cycle life, and the electricity sources on the results. It is found that repurposing spent LIBs with 50/50 allocation method has the poorest environmental performance and is not sufficiently advantageous over using LABs. Moreover, extending the cycle life of repurposed LIBs and using a cleaner energy mix significantly reduce environmental impacts. This study offers implications to mitigate the end-of-life management problem of EV LIBs, including a life cycle management platform, an effective integration of the supply chain, and references for the ongoing green transition of the communication industry.