Supply Chain Risks of Critical Metals: Sources, Propagation, and Responses

In the era of globalization, critical metals industries are organized through the global supply chain. However, the global supply chains have been disrupted since 2020 by the outbreak of Covid-19 and a serious of geopolitical crises. To better address the supply chain challenges of critical metals, a review is needed about the risk sources, propagation of risks, and responses to the supply chain risks. Firstly, this review provides an overview about the research progress in identifying the risk sources and assessing the risks, and then proposes a new supply chain framework for risk analysis of critical metals. This supply chain risk framework categorizes relevant risk factors into upstream risks, middle-stream risks, downstream risks, and general risks. Secondly, this review offers a comprehensive understanding about how the risks propagate horizontally and vertically. Finally, responses such as supply diversification, stockpiling, material substitution, recycling and circular economy strategy, price volatility hedging, and supply chain traceability are reviewed. This review features in the supply chain perspective and overview on the network-based studies. The review results affirm the urgency and need for further studies on the supply chain risks and resilience, which are strongly connected to a smooth clean energy transition.