The rate characteristics of lithium iron sulfide

The electrochemical rate properties of Li2FeS2 synthesized via a low cost solid state method have been investigated. Apparent diffusion coefficients calculated from EVS and GITT measurements show rate limitations upon charge with distinct differences between the iron redox and sulfur redox regions. These differences between the iron and sulfur redox reactions are not mimicked upon discharge. The apparent diffusion coefficients are greater upon discharge than charge and this is reflected in the rate capabilities as measured by galvanostatic discharge and charge measurements.