Potassium-ion batteries (KIBs) are important alternatives to lithium- and sodium-ion batteries. Herein, microsized a Bi electrode delivers exceptional potassium storage capacity, stability, and rate capability by the formation of an elastic and adhesive oligomer-containing solid electrolyte interface with the assistance of diglyme electrolytes. The kinetics-controlled K–Bi phase transitions are unraveled combining electrochemical profiles, in situ X-ray diffraction and density functional theory calculations. Reversible, stepwise Bi–KBi 2–K 3Bi 2–K 3Bi transitions govern the electrochemical processes after the initial continuous surface potassiation. The Bi electrode outperforms the other anode counterparts considering both capacity and potential. This work provides critical insights into the rational design of high-performance anode materials for KIBs.
- phase transitions
- potassium-ion batteries
ASJC Scopus subject areas
- Renewable Energy, Sustainability and the Environment
- General Materials Science