Cobalt is a cornerstone material for lithium-ion batteries and electric vehicles, yet its global supply chain is increasingly exposed to systemic risks that go far beyond isolated supply disruptions. This study reveals how shocks originating in one country or production stage can cascade across borders and life-cycle stages, triggering widespread failures throughout the global cobalt supply chain network. By integrating material flow analysis with a multilayer shock propagation model, the research demonstrates that systemic risks concentrate upstream but accumulate most severely at refining and manufacturing bottlenecks. Alternating horizontal/vertical and direct/indirect shock propagation pathways lengthen cascades, expose multistage knock-ons, and produce abrupt, nonlinear breakdowns, highlighting that conventional, country-level risk assessments underestimate the true vulnerability of the cobalt supply system and that system-level coordination is essential for resilience.
As electric vehicles and energy storage systems expand worldwide, demand for cobalt has surged, intensifying concerns over supply security, geopolitical concentration, and environmental and social risks. Traditional assessments of critical minerals often evaluate countries, materials, or trade flows in isolation, overlooking the dense upstream–downstream interdependencies that characterize modern supply chains. Recent disruptions—from export restrictions and trade tensions to pandemic-related shocks—have shown that even localized disturbances can ripple through global production systems. However, existing analytical frameworks struggle to capture how risks propagate across multiple production stages and economies simultaneously. Based on these challenges, it is necessary to conduct in-depth research on cobalt supply chain risks from a systemic, network-based perspective.
In a study (DOI: 10.1016/j.ese.2025.100654) accepted in Environmental Science and Ecotechnology and published online in late 2025, researchers from institutions including the Chinese Academy of Sciences, Peking University, and the University of Southern Denmark analyzed global cobalt flows from 1998 to 2019. Using a multilayer supply chain network and an iterative shock propagation model, the team examined how disruptions spread horizontally across countries and vertically across six life-cycle stages, from mining and refining to manufacturing, use, and recycling. Their findings offer one of the most comprehensive assessments to date of systemic risk in the global cobalt supply chain.
The researchers constructed a global cobalt supply chain network linking 230 countries across six interconnected production stages, combining trade-linked material flow analysis with a dynamic shock-propagation model. This approach allowed them to simulate how supply shortages or demand reductions in one node could trigger cascading failures throughout the system. The results show that shocks propagate through alternating direct and indirect pathways, often traveling across both trade relationships and domestic production chains. While mining disruptions—particularly in highly concentrated upstream regions—are frequent risk sources, the most severe systemic impacts accumulate at refining and manufacturing "bridges", where dense vertical and horizontal connections amplify failures.
The analysis reveals that the resulting "avalanche network" of potential failures is roughly four times denser than the physical trade network itself, indicating extensive hidden interdependencies. Countries such as China and the United States exhibit high systemic fragility, meaning disruptions originating there can trigger widespread collapses. Conversely, several countries with relatively small production volumes but high exposure rates are particularly vulnerable to common random disruptions and lack resilience or effective response. Overall, the study finds that global cobalt supply risks have followed a volatile yet rising trend over the past two decades, driven by increasing concentration and misalignment between supply and demand.
The authors emphasize that the cobalt supply chain displays a "robust-yet-fragile" structure: it can absorb random, small-scale disruptions, yet remains highly vulnerable to targeted shocks at critical nodes. They note that interventions such as national stockpiling or reshoring may reduce risks for individual countries but can unintentionally shift vulnerabilities elsewhere in the system. According to the research team, improving resilience requires coordinated, stage-aware strategies that recognize upstream–downstream coupling rather than isolated national responses. Without such system-level thinking, efforts to secure critical minerals for the energy transition may exacerbate, rather than alleviate, global supply instability.
The findings carry important implications for energy policy, critical mineral governance, and industrial strategy. By revealing where risks originate, accumulate, and propagate, the framework can support early-warning systems for supply disruptions and guide more effective international cooperation. Policymakers can use these insights to design joint stockpiling mechanisms, diversify refining and manufacturing capacity, and evaluate the systemic consequences of trade restrictions or decoupling strategies. Beyond cobalt, the approach can be applied to other critical materials essential for batteries and clean energy technologies. Ultimately, the study suggests that ensuring a stable low-carbon transition depends not only on securing resources, but on managing the complex networks that connect them.
