MO.3.C || Circularity and Life Cycle Aspects of Recycling Technologies

Popien, Jan-Linus; Thies, Christian; Spengler, Thomas S.

Due to the increasing demand for traction batteries and related raw materials, recycling of waste batteries and returning secondary raw materials play a major role to reduce the risk of shortages and ensure economic success, especially in resource-dependent regions such as Europe. Besides, recycling of waste batteries could reduce the environmental and socio-economic impact of a battery pack by avoiding primary raw material extraction. However, it must be demonstrated that possible recycling routes and the return of secondary materials are beneficial in terms of their environmental and socio-economic impacts, which can be assessed with the Life Cycle Sustainability Assessment (LCSA) approach. The integration of recycling leads to different co-products, which brings the challenge of allocating recycling impacts to the different products. For this, different allocation rules such as the cut-off, the end-of-life, or the 50/50 approach can be used. These allocation rules are mainly used for environmental assessment, whereas the use of allocation rules within economic and social assessments is not well researched. It is unclear whether these allocation rules are easily transferable to economic and social assessments and how the use of different allocation rules within an LCSA affects the results and the system definition. This paper aims to provide a better understanding of allocation rules in an LCSA in the context of battery supply chains. For this purpose, different allocation rules are specified and an example implemented in the Brightway2 framework is used to show how the allocation rules can influence the results and the system definition. First results show that the choice of allocation rules affects all impact indicators and potentially biases the conclusions regarding the advantageousness of individual recycling routes. This underlines that the choice of allocation rules has to be made with caution and a detailed analysis of allocation rules is necessary.