(119e) Tracking Embodied Co, Li, Mn, and Ni Material Flows in the US through Economic Input-Output-Based Network Analysis

The transition toward cleaner energy and electric vehicles (EVs) is creating unprecedented demand for mineral resources on which these technologies rely. For many of these minerals, the US is currently significantly dependent on imports (between 50 – 100%), often from countries that are geopolitically sensitive. Securing the supply of these so-called ‘critical materials’ is therefore crucial for a successful transition to cleaner energy and EVs. An essential step in securing the supply of critical materials is tracking their flows within the economy and understanding their usage to elucidate opportunities for efficiency, substitution and recycling. Established methods for material flow tracking depend heavily on empirical data that are resource intensive to procure, thereby limiting the reproducibility of many material flow analyses and their application to supply chain modeling. This study presents an economic input-output (IO)-based framework for characterizing the national trade structure of embodied critical materials. We generate national IO models for select lithium-ion battery materials using annual industry consumption data and the US national IO accounts at the detailed sector level. The focus in this study is on characterizing cobalt, lithium, manganese, and nickel flows to demonstrate the use of the modeling framework, which could then be applied to other materials for which annual industry consumption data are available. To uncover competing uses and potential secondary sources for these materials, we further use network analysis to identify significant sectors in the domestic metals supply chains. Initial estimates of the potential recoverable secondary supply of cobalt, lithium, manganese, and nickel from the sectors highlighted by the network analysis using multiple metrics are presented as a precursor to more detailed analyses of the sector-specific uses of these materials in future work.