Preparation of Si-graphite dual-ion batteries by tailoring the voltage window of pretreated Si-anodes

Abstract

As a promising energy storage system, silicon-graphite dual-ion batteries, which are based on the alloying/dealloying of lithium ions in silicon anode, are proposed for the first time. The recent demonstration of anion interaction in graphite layers exhibits the valuable prospects of graphite as an alternative to traditional cathode materials. Dual-ion batteries have demonstrated the characteristics of low cost and high safety and have environmental benefits over other Li-ion batteries. Dual-ion batteries have previously been established, but they require more stable electrolytes under high voltage range. Because most solvents easily decompose at a voltage above 5.2 V, herein, the voltage window of the silicon anode (SA) has been rationally tailored to match that of the graphite cathode (GC). In addition, cycling stability in the full cell was obtained in the commonly used electrolyte of SL:EMC with LiPF6. This design strategy shows great potential and value for applications in dual-ion batteries when compared to traditional Li-ion batteries.