The impact of solid-state batteries on greenhouse gas emissions of batteries from the life cycle perspective

The greenhouse gas (GHG) emissions from lithium-ion batteries (LIBs) have attracted widespread attention. Currently, the characteristics and reduction strategies of batteries GHG emissions under the influence of solid-state batteries (SSBs) remain unclear. Therefore, this study combines material flow analysis with the emission factor methods to construct a systematic GHG emissions accounting model for the coexistence of SSB and liquid batteries. It will reveal the GHG emission characteristics of five typical battery chemistries (LFP, LCO, LMO, NCM, and NCA). In addition, this study examines the evolution and the reduction strategies of GHG emissions under the influence of SSB and energy transition through scenario analysis. The results show that the LFP battery had the highest life-cycle GHG emissions among the five batteries in 2023 in China. If no measures are taken, the total emissions are expected to increase by 350% by 2035. It is worth noting that SSB substitution scenarios have not achieved net emissions reductions in the short term. It is difficult to achieve carbon reduction solely through material changes such as SSB. Material changes require the cooperation of green power and energy transition to achieve a 49% reduction in emissions. The standardized waste management and green power scenarios can achieve significant reductions in emissions. It is important to note that the deployment of green power in specific regions should align with enterprises' geographical locations to ensure synergy between carbon reduction and economic benefits. Although cascading utilization extends battery lifespan, its potential for reducing emissions is not as significant as expected. The study has identified key strategies for the battery industry to reduce life-cycle emissions, providing a scientific basis for policy formulation.