Determination of the Lithium Ion Diffusion Coefficient in Graphite

A complex impedance model for spherical particles was used to determine the lithium ion diffusion coefficient in graphite as a function of the state of charge (SOC) and temperature. The values obtained range from of to at 25°C for 0 and 30% SOC, respectively, and for 0% SOC, the value at 55°C was . The conventional potentiostatic intermittent titration technique (PITT) and Waburg impedance approaches were also evaluated, and the advantages and disadvantages of these techniques were exposed. © 1999 The Electrochemical Society. All rights reserved.