Environmental assessment of secondary materials from battery recycling process chains: the influence of recycling processes and modelling choices

Abstract

The environmental assessment of lithium-ion batteries and the circularity of their materials is a highly discussed field. The new EU Battery directive demands OEMs to quantify the environmental footprint of their products. Further, the Directive sets goals for the use of secondary materials, for which OEMs request the environmental footprint. Therefore, a comparative life cycle assessment of secondary materials recovered in different recycling process chains becomes necessary. A literature review was performed to identify how comparative life cycle assessments of recycling processes are structured regarding goal and scope definition and modelling choices. The process focus in these assessments makes the identified best practices only to a limited extent applicable for the quantification of the environmental footprint of secondary materials. In this paper, influencing factors of a life cycle assessment in recycling are analysed and discussed. Special focus lies on the appropriate allocation of environmental impacts to secondary materials and process steps in a recycling process chain. The challenges are exemplified with a closer look to a recycling process combining pyro, hydro and mechanical treatment to recover various materials.