Electronic and Ionic Wirings Versus the Insertion Reaction Contributions to the Polarization in LiFePO4 Composite Electrodes

electrode are experimentally discriminated in this work. The electrodetotal resistance is dominated at high rate by the contribution of the electronic and the ionic wires, the former being more importantin the case of electrodes with low compaction, while the latter being more important in the case of electrodes with highcompaction. A porosity in the 35%–40% range allows to minimize the electrode polarization. At low rate, the electrode resistanceis dominated by the resistance to lithium insertion into the active mass and follows the predictions of M. Gaberscek and J. Jamnik