High Performance of a Polydopamine-Coated Graphite Anode with a Stable SEI Layer

Abstract

In this work, we uniformly coated polydopamine (PD) on the surface of graphite particles, thereby enhancing both the rate capability and cyclability of the graphite anode. The wet-based coating method enabled the formation of a uniform PD layer on the graphite surface. We investigated two different coating methods: electrode-scale and powder-scale coating methods. We studied the battery performance of the graphite anode with various PD coating times. PD worked as an artificial solid electrolyte interphase (SEI) layer, thus preventing direct contact between the electrolyte and the graphite surface, while forming an ion-conducting path for Li ions. Thus, the PD-coated graphite electrode showed higher capacity retention and lower resistance compared to graphite because of the high stability of PD as an artificial SEI layer.