Potassium-ion batteries (KIB) are a promising complementary technology to lithium-ion batteries because of the comparative abundance and affordability of potassium. Current KIB chemistry lacks an electrolyte which is consistently stable at the the required high operating potential, and this is a critical hurdle to overcome.
This paper, published in Chemistry of Materials, explains how the researchers combined a KMF cathode and a graphite anode with a KFSI ionic liquid electrolyte for the first time, gaining unprecedented performance. A high through-put technique was used to optimize the KMF morphology for operation in this electrolyte system.
In the same ionic liquid electrolyte, the graphite showed excellent electrochemical perofrmance, and the authors demonstrate reversible cycling by operando X-ray diffraction.
These results are a significant and essential step toward viable potassium-ion batteries.