The Role of Modified Graphene in Cathode Formulations for Lithium-Ion Batteries

Abstract

We explored the effect of reduced graphene oxide (RGO) on LiNi 0.5 Mn 1.5 O 4 (LNMO) and on 0.6LiMnPO 4 -0.4Li 3 V 2 (PO 4 ) 3 (LMVP) composite cathodes with carbon black (C65). We demonstrated that the effect of RGO depends on the cathode active material. Indeed, RGO improves cycling stability of LNMO cathodes by improving electrode/electrolyte interface stability at high potentials. On the contrary, RGO worsens the performance of LMVP/C65 and it has no effect on LMVP electrodes when it is produced in situ during LMVP synthesis in presence of graphene oxide. Our study indicates that at least 10 wt. % of C65 is necessary for good performance of the poor conductive LMVP.