Advancements and Perspectives on Nonaqueous Electrolyte Engineering for Graphite Anode in Potassium-Ion Battery

Potassium-ion batteries (KIBs) have emerged as a promising alternative to lithium-ion batteries due to the abundance and low cost of potassium resources. Coupled with commercial graphite anode, KIBs have great potential for the next-generation large-scale electrochemical energy storage devices. However, graphite anode in KIBs suffers from rapid capacity decay in commercial "potassium hexafluorophosphate (KPF6) + ethylene carbonate (EC)" electrolytes. These issues can be addressed through electrolyte engineering, which has been proven effective in improving graphite performance. This review explores the underlying mechanisms of K+ storage in graphite, the challenges of electrolyte design, and the recent advancements in electrolyte engineering for graphite anode optimization in KIBs.