Reuse of Lithium Iron Phosphate (LiFePO4) Batteries from a Life Cycle Assessment Perspective: The Second-Life Case Study

Abstract

As of 2035, the European Union has ratified the obligation to register only zero-emission cars, including ultra-low-emission vehicles (ULEVs). In this context, electric mobility fits in, which, however, presents the critical issue of the over-exploitation of critical raw materials (CRMs). An interesting solution to reduce this burden could be the so-called second life, in which batteries that are no longer able to guarantee high performance in vehicles are used for other applications that do not require high performance, such as so-called stationary systems, effectively avoiding new over-exploitation of resources. In this study, therefore, the environmental impacts of second-life lithium iron phosphate (LiFePO4) batteries are verified using a life cycle perspective, taking a second life project as a case study. The results show how, through the second life, GWP could be reduced by ‒5.06 × 101 kg CO2 eq/kWh, TEC by ‒3.79 × 100 kg 1.4 DCB eq/kWh, HNCT by ‒3.46 × 100 kg 1.4 DCB eq/kWh, ‒3.88 × 100 m2a crop eq/kWh, and ‒1.12 × 101 kg oil eq/kWh. It is further shown how second life is potentially preferable to other forms of recycling, such as hydrometallurgical and pyrometallurgical recycling, as it shows lower environmental impacts in all impact categories, with environmental benefits of, for example, ‒1.19 × 101 kg CO2 eq/kWh (compared to hydrometallurgical recycling) and ‒1.50 × 101 kg CO2 eq/kWh (pyrometallurgical recycling), ‒3.33 × 102 kg 1.4 DCB eq/kWh (hydrometallurgical), and ‒3.26 × 102 kg 1.4 DCB eq/kWh (pyrometallurgical), or ‒3.71 × 100 kg oil eq/kWh (hydrometallurgical) and ‒4.56 × 100 kg oil eq/kWh (pyrometallurgical). By extending the service life of spent batteries, it may therefore be possible to extract additional value while minimizing emissions and the over-exploitation of resources.