Prospective environmental and resource sustainability assessment of advanced matching technologies for sodium-ion and lithium-ion batteries

Current life cycle assessment (LCA) studies of batteries focus on single chemistry systems or single-dimensional evaluations, with limited consideration of the resource and environmental sustainability impacts of hybrid chemistry systems incorporating next-generation batteries. Environmental impacts and supply risks of 9 single chemistry and 12 hybrid chemistry system batteries are quantitatively compared based on LCA in this study. Patterns of environmental and resource performance in hybrid systems as the matching ratio varies are investigated and methodology for comprehensive assessment of the environmental-resource sustainability in batteries is proposed. Results indicate that sodium-ion batteries (SIBs) (excluding vanadium-based) avoid the use of nickel and cobalt, which are scarce and associated with high supply risks. They exhibit lower environmental impacts, and supply risk can be reduced by more than 70% compared to lithium-ion batteries (LIBs). Environmental impact and supply risk of hybrid chemistry systems are fundamentally determined by the regulation of matching ratios and the selection of specific chemistry combinations. Incorporating low-risk SIBs while controlling the proportion of LIBs can minimize resource and environmental burdens. Iron-based SIBs demonstrate the best resource-environmental performance. Hybrid system combining them with a small proportion (e.g., 25%) of high-nickel LIBs can enhance energy density while maintaining a low comprehensive score (<0.5). This represents an ideal strategy for balancing performance and sustainability. This study provides valuable insights for policymakers and industries to optimize the production of current and future batteries and identify optimal battery matching technology. It holds significant importance for building more resilient and sustainable supply chains.