Life cycle assessment (LCA) is a methodology used to evaluate the inputs, outputs, and the environmental impacts of products and systems in all stages of the life cycle, and it has been widely used for analyzing impacts of lithium-ion batteries. Although large amount of information is available on the environmental impacts of batteries in numerous LCA studies, the results from different studies can vary significantly. Moreover, LCA alone is not enough to assess all the necessary aspects for circular economy of batteries. Numerous indicators have been developed for evaluating circularity, which aim to recognize aspects related to e.g. durability, repairability, usage intensity and resource efficiency in general. The scope and purpose of different indicators varies, therefore relevant indicators need to be chosen case by case.

This paper presents the results of a study evaluating the circularity and environmental impacts of lithium-ion batteries, defining the best available complementary methods to LCA for evaluating the sustainability of batteries. Systematic literature review of recent LCA studies on lithium-ion batteries is carried out as well as review of most important circularity indicators and their applicability for batteries. Demands coming from the EU Battery Regulation and standardization are also considered. The aim is to define what kind of data is needed for the assessment, where most significant impacts arise, what are the reasons behind the variety in results, where are the main data gaps and what are the shortcomings of current methods. As part of the study, a case investigation of the NMC811 battery for electric vehicles is presented including generic LCA study based on databases and literature. In addition, selected circularity indicators are tested for the case battery to evaluate their potential to complement LCA for more holistic assessment of batteries.