SnO2 as an alloy anode for Li-based dual-ion battery with enhanced performance

Dual-ion batteries are emerging energy storage devices with dual-ion-involved charge storage mechanisms. In this work, we have proposed SnO2 as an anode for dual-ion battery (DIB) applications with a restricted potential window (<1 V vs. Li/Li+). More importantly, the choice of electrolyte will be ethylene carbonate-free solvents, known for their film-forming abilities. Unfortunately, it hinders the anion intercalation into graphitic structures. Fluoroethylene carbonate (FEC) has been used as an additive, which allows both the anions and cations involved in the electrochemical reaction. Accordingly, DIB was assembled with an alloying-type SnO2 anode and recovered graphite from spent lithium-ion batteries as a cathode exhibiting an excellent energy density of ∼110.3 Wh kg–1.