As a typical polyanionic cathode material,potassium vanadium fluorophosphate(KVPO4F,KVPF)has the advantages of high theoretical capacity,high working voltage,and good thermal stability,and thus holds broad application prospects in the field of potassium-ion batteries.However,KVPF is confronted with issues such as poor cycling and rate performance caused by its low electronic conductivity and unstable electrolyte/electrode interface,which severely restricts its practical application in potassium-ion batteries.In response to the above problems,this paper adopts the sol-gel and high temperature calcination method to prepare the KVPF cathode material and investigates the influence mechanism of the calcination temperature on the structure and electrochemical properties of the cathode material.The results show that the KVPF cathode material calcined at 650 ℃ has a more uniform distribution and smaller grain size,exhibiting more excellent electrochemical properties.In the voltage range of 2.0-4.8 V,the KVPF can deliver a capacity of 96.8 mA·h·g-1 at 0.1 C,and the capacity retention rate is 63％after 30 cycles.
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