Carbon nanofibers improve both the electronic and ionic contributions of the electrochemical performance of composite electrodes

► Carbon nanofibers as conductive additive for LiFePO4-based composite electrode for lithium battery. ► A new method is used that allows discriminating between the electronic and the ionic wirings contributions to the electrochemical performance. ► Carbon nanofibers improve both the electronic conductivity and the ionic conductivity of the composite electrode.