Ultrafast charging of LiFePO4 with gaseous oxidants under ambient conditions

Abstract

Lithium iron phosphate is a lithium-ion battery positive electrode material with widespread use, as well as, unusually complex redox chemistry. Here we report on the discovery of a direct gas–solid delithiation reaction. Unique to this reaction, in addition to the lack of solvent, is remarkably fast kinetics. In situ X-ray diffraction, corroborated by elemental analysis, shows for the first time that LiFePO₄ bulk diffusion supports nearly complete delithiation/charging of carbon coated LiFePO₄ micropowder at ambient temperature in less than 60 seconds.