Lithium-ion batteries (LIBs) will play a crucial role in achieving decarbonization and reducing greenhouse gases. If the EU wants to be competitive in the global market of LIBs, it has to ensure a sustainable and secure supply of the raw materials needed for the manufacturing of these batteries. Limited understanding of how the battery material cycles are linked with raw materials supply chains may hinder policy measures targeting the set-up of a domestic supply chain in the EU since no precise information on where to intervene will be available. The novelty of this work lies in a multilayer system approach developed to reveal interlinkages between the flows of five raw materials contained in LIBs (cobalt, lithium, manganese, natural graphite, and nickel) in the EU.This was achieved by aligning material system analysis datasets of raw materials contained in LIBs with datasets on stocks and flows of this type of batteries in the EU. The results demonstrate the EU's strong import dependency on LIBs and battery raw materials. The EU recycling of lithium and natural graphite is low/nonexistent hindering the sustainable supply of these materials. The results also show that the majority of battery materials are increasingly accumulated in use or hoarding stocks. The proposed approach is designed to help identify bottlenecks and possible solutions to increase the efficiency of the EU LIB system, which could go unnoticed if each material supply chain were examined individually. This study also highlights how the lessons learned can support EU resource-management policies.

A comprehensive data inventory of the current materials cycle in industry and society is crucial for an informed discussion and for decision‐making on the supply of raw materials. Particularly, it is key to understand how these materials are functionally and nonfunctionally recycled, and enable the assessment of recycling indicators needed for the monitoring of circular economy. In this context, a material system analysis (MSA) of cobalt for the European Union (EU) from 2012 to 2016 is presented and discussed. Detailed results are provided for the year 2016, and the evolution of the flows over time is presented from 2012 to 2016. In addition, six indicators are calculated to characterize the cobalt cycle. In 2016, the EU28 embedded around 24,000 metric tons (t) of cobalt in manufactured products, and 33,700 t were put into use. The main losses of the system are due to nonselective collection of postconsumer waste (disposed), and nonfunctional recycling of old scrap. From the years analyzed, it was possible to detect a shift in the imports; the import of primary material decreased more than 99% between 2012 and 2016, and the import of semiprocessed and processed materials increased around 31% in the same period. This indicates that after 2012, the EU became more dependent on imports in downstream stages of the supply chain. One way to decrease this dependency is to establish higher collection targets, and to establish recycling targets based on the recovery of single materials, in order to decrease the amount dissipated through nonfunctional recycling.