Authors: Rongyu Deng, Ashok S. Menon, Marc Walker, Louis F. J. Piper, Alex W. Robertson, Feixiang Wu
Published: 2025-03-23
Source: Full article
AbstractThe development of aqueous Zn/LiCoO2 hybrid batteries faces challenges such as poor reversibility, rapid capacity degradation, and severe side reactions in base electrolytes. Herein, this study proposes Al2O3 nanoparticles as a bifunctional additive in the base electrolyte, leading to a novel electrolyte that enhances the interfacial stability between electrolyte and electrode and improves the electrochemical performance. Al2O3 reduces water molecules activity, inhibits the interfacial side reactions, and enhances the reversibility and stability of redox reactions. Molecular dynamics (MD) simulations reveal that Al2O3 modifies the solvation structures of both Li+ and Zn2+, lowers their de‐solvation energies, thereby improving ionic diffusion coefficients and reaction kinetics. Consequently, symmetric cells achieve a prolonged cycle life with uniform zinc deposition. Zn/LiCoO2 hybrid cells exhibit excellent rate performance, maintaining 81 mAh g−1 at 0.8 A g−1 and stable cycling over 300 cycles at 0.4 A g−1 within a broadened voltage range of 1.5–2.15 V versus Zn/Zn2+. Additionally, these cells demonstrate ultrahigh capacity retention of 98.2% at 0 °C and 87% at a high mass loading of 5 mg cm−2 at 0.4 A g−1. This study presents a promising additive strategy for enhancing the stability and performance of high‐voltage aqueous hybrid batteries, paving the way for their practical application.