China's lithium supply chains: Network evolution and resilience assessment

As the world's largest consumer of lithium resources, China faces a substantial demand-supply gap and challenges in securing its lithium supply chain. This study aims to examine the evolution of China's lithium supply chain networks from 2017 to 2021 and employs an attack model to reveal network resilience. A lithium supply chain network is constructed across the entire industry, offering a novel perspective for examining the resilience of lithium resource trade networks. Simulated disturbances are executed via attack models, analysing not only trade nodes but also specific trade relationships while differentiating between import and export subnetworks, thus providing an in-depth examination of structural evolution and resilience characteristics. Our findings highlight the rapid decrease in total lithium throughflows and stable network efficiency from 2017 to 2021. A decline is also observed regarding the network's resilience. Among the different forms of simulated disruptions, node attacks exert the most substantial impact on resilience. The effects of node and edge attacks are notably less severe in China's export subnetwork than in its import subnetwork. In the import subnetwork, the influence of Asian and European nodes diminishes, while South America and Oceania show an increasing influence trend. For exports, the Asian node remains influential, followed by Europe, with Eastern Europe surpassing Western Europe. Upon closer examination of specific products' trade impacts under edge attacks, the results indicate that most trade relationships have minimal impacts on network resilience. There is a persistent increase in the influence of key upstream products in the import sector. Similarly, the influence of key downstream products in the export sector is also on the rise, underscoring China's global leadership in both mid- and downstream products and illustrating its expanding production capacity. The structural changes of complex networks and simultaneous targeted attacks provide new insights for enhancing resilience given the different disruptions of nodes and edges, and outline important policy implications for China's lithium supply security.