Arginine Cations Inhibiting Charge Accumulation of Dendrites and Boosting Zn Metal Reversibility in Aqueous Rechargeable Batteries
Zehai Chen, Hongzhan Chen, Youcai Che, Cheng Luo, Hao Zhang, Jian Chen, Fangyan Xie, Nan Wang, Yanshuo Jin, Hui Meng
Abstract
Aqueous zinc-ion batteries are regarded as one of the new promising rechargeable batteries. However, serious Zn dendrite growth causes short-circuit issues in the batteries. Herein, we report that arginine (Arg), a cationic surfactant electrolyte additive, can inhibit irregular and nonplanar dendrite growth and induce uniform Zn deposition. It shows a long cycle life (515 h) of Zn/Zn cells in the electrolyte containing Arg, which is ∼10 times longer than that of the electrolyte with no additive. The hydrolysis of Arg produces arginine cations (Arg+), which will be preferentially adsorbed on Zn dendrites due to the tip charge accumulation effect during the Zn plating process. Arg+ increases the overpotential for the nucleation of Zn dendrites and results in uniform Zn deposition. After about 350 cycles, the MnO2/Zn cell shows 84.59% capacity retention and 99.85% average Coulomb efficiency in the electrolyte with the additive. The low-cost and nontoxic electrolyte additive identified in this work provides a new pathway toward inducing regular Zn deposition morphology.