Evaluation of electrochemical interface area and lithium diffusion coefficient for a composite graphite anode

A structural model to calculate the electrochemical interface area for a composite graphite electrode is described. A new equation using the model predicted area to calculated chemical diffusion coefficient (D_Li+) eliminates the effects from fabrication such as active mass (m_B) and geometric area (S_Geo). The chemical diffusion coefficient values calculated for graphite electrodes of different thicknesses and porosities using the new equation are almost the same as expected. The values of D_Li+ in the graphite vary between 10^-11.9 and 10_-9.9 cm ₂/s over the course of the lithium deintercalation in the graphite samples.