From Source to Sink: A Route-Based Approach to Supply Chain Stability

Modern global trade networks are characterized by complex interdependencies, making supply chain stability for critical commodities a key concern. Expanding the range of trade partners may seem like a straightforward way to enhance resilience, but it can still leave countries exposed if partners rely on the same upstream suppliers. This highlights the need for a more comprehensive approach that traces commodities from their sources to final consumption.We adapt the power tracing technique from electrical grid analysis [1] to address this issue. Originally designed to quantify dependencies between generators and consumers by analyzing electricity flows, we apply this concept to trace commodity pathways in global trade. Using a Markov chain model, our framework simulates the flow of goods and reconstructs observed trade distributions, revealing risks and structural dependencies. We further develop a multilayer framework linking commodity flows across stages of production.We demonstrate the framework's utility through its application to Lithium-Ion Batteries (LIBs) for electric vehicles (EVs). By tracing materials like lithium from mining to final consumption, we identify supply chains balancing route diversity with environmental and human rights standards. This perspective reveals key vulnerabilities and offers strategic guidance for resilient trade portfolios. At the global level, it pinpoints critical hubs and potential failure points that could disrupt supply chains. Incorporating raw materials, intermediate goods, and final products, our method provides a unified framework for analyzing interdependencies and their impacts.