Co-solvent electrolyte-induced zinc anode surface reconstruction for high performance zinc ion batteries

The progress of rechargeable zinc (Zn) ion batteries (RZBs) has been significantly impeded by the occurrence of side reactions and dendritic issues on Zn anodes, which are attributed to the intricate reaction kinetics observed in aqueous electrolytes. Herein, we propose a co-solvent electrolyte comprising a combination of N, N-dimethylformamide (DMF) and Dimethyl sulfoxide (DMSO). This electrolyte reconstructs the surface of the Zn anode and generates a dense and robust solid electrolyte interface (SEI), which promotes uniform Zn 2+ deposition and enhances Zn 2+ transport kinetics. The DFT further shows that the electrolyte has a unique solvated structure which enables uniform Zn 2+ deposition and the creation of stable SEI. By utilizing these advantages, the co-solvent electrolyte is capable of enduring uninterrupted cycling for more than 4000 h at a current density of 1 mA cm −2 , and for over 2000 h at a current density of 5 mA cm −2 . Furthermore, the Zn||NH 4 V 4 O 10 full cell demonstrated exceptional electrochemical performance with regard to charge/discharge capacity and cycle stability. This study showcases the effectiveness of non-aqueous electrolytes, which will enable the progress of secure and high-capacity RZBs.