Structure and Resilience of Lithium and Cobalt Supply Chains: A Multilayer Complex Networks Approach

Growing demand for personal electronics and electric vehicles necessitates an increasing demand for lithium-ion batteries (LIBs). The capacity to extract, refine, and transport lithium and cobalt commodities will determine the global ability to meet this demand. Production of these commodities has already resulted in negative social and environmental impacts, and the supply chain has faced considerable risk. To study the structural characteristics of the supply chains and assess its dynamics under shock, two multi-layer complex network models were constructed. Both networks were built using production and trade data to quantify the flow of lithium and cobalt through the global economy. Commodities were categorized as either upstream, midstream, or downstream, according to the level of processing required for production. The lithium supply network is analyzed according to its topological features and vertex characteristics to better understand its structure and key actors. An agent-based model is being developed to study the dynamics of risk propagation through the network under different scenarios involving a supply-side shock. On-going work seeks to extend this analysis to the cobalt supply chain and further develop the risk-propagation model.