Zn-Ion Transporting, In Situ Formed Robust Solid Electrolyte Interphase for Stable Zinc Metal Anodes over a Wide Temperature Range

Abstract

Hydrogen evolution, corrosion, and dendrite formation in the Zn anodes limit their practical applications in aqueous Zn metal batteries. Herein, we propose an interfacial chemistry regulation strategy that uses hybrid electrolytes of water and a polar aprotic N,N-dimethylformamide to modify the Zn 2+solvation structure and in situ form a robust and Zn 2+ -conducting Zn 5 (CO 3 ) 2 (OH) 6 solid electrolyte interphase (SEI) on the Zn surface to achieve stable and dendrite-free Zn plating/stripping over a wide temperature range. As confirmed by 67 Zn nuclear magnetic resonance relaxometry, electrochemical characterizations, and molecular dynamics simulation, the electrochemically and thermally stable Zn 5 (OH) 6 (CO 3 ) 2 -contained SEI achieved a high ionic conductivity of 0.04 to 1.27 mS cm −1 from −30 to 70 °C and a thermally activated fast Zn 2+ migration through the [010] plane. Consequently, extremely stable Zn-ion hybrid capacitors in hybrid electrolytes are demonstrated with high capacity retentions and Coulombic efficiencies over 14,000, 10,000, and 600 cycles at 25, −20, and 70 °C, respectively.

Dual Pre-Insertion Strategy to Achieve High-Performance Vanadium Oxide toward Advanced Cylindrical Zinc Ion Batteries

“…The Ragone plot of ZnVO·1.2H 2 O is shown in Figure S9. Compared with those of recently reported cathode materials for the AZIB, ,,,− the ZnVO·1.2H 2 O//Zn exhibits higher energy density and power density (252.5 Wh kg –1 at 173.0 W kg –1 ).”…”

Designing multidimensional hydration inhibitor towards the long cycling performance of zinc powder anode

“…2g, there are two peaks at 532.5 eV and 531.4 eV when the Zn powder/PG anode was cycled in the electrolyte without CAVImBr, which are assigned to S–O and Zn–O. 41,42 The existence of Zn–O was ascribed to the by-product caused by the corrosion of the anode by H 2 O molecule in the pure aqueous electrolyte. 43 In comparison, the Zn–O peak was not observed in the XPS spectrum of Zn powder/PG anode after cycling with the CAVImBr-modified electrolyte, which is attributed to the fact that CAVImBr effectively prevented the contact of water molecules in the electrolyte with the electrode.…”

Charge-Transfer Complex-Based Artificial Layers for Stable and Efficient Zn Metal Anodes

“…This reflects the desolvation ability of hydrate Zn 2+ , which is one of the most important processes in the electrodeposition and affects the interfacial redox kinetics of the Zn-metal anode. 47,48 As displayed in Figure S21 and Table S1, after fitting the Nyquist plots of the Zn||Zn cells in different electrolytes at the temperature range from 30 to 80 °C, a very low R ct is obtained in TCNQ-based electrolyte at each corresponding temperature, implying an improved capability of the TCNQ-derived interphase for Zn 2+ transfer. Moreover, Zn(TCNQ) 2 features a good bulk ionic conductivity (∼2.1 × 10 −4 S cm −1 , Figure S22), which facilitates the Zn 2+ diffusion through this interfacial layer.…”