A Dual‐Functional Organic Electrolyte Additive with Regulating Suitable Overpotential for Building Highly Reversible Aqueous Zinc Ion Batteries

Abstract

Aqueous zinc ion batteries (AZIBs) with high safety, low cost, and eco‐friendliness advantages show great potential in large‐scale energy storage systems. However, their practical application is hindered by low Columbic efficiency and unstable zinc anode resulting from the side reactions and deterioration of zinc dendrites. Herein, tripropylene glycol (TG) is chosen as a dual‐functional organic electrolyte additive to improve the reversibility of AZIBs significantly. Importantly, ab initio molecular dynamics theoretical simulations and experiments such as in situ electrochemical impedance spectroscopy, and synchrotron radiation‐based in situ Fourier transform infrared spectroscopy confirm that TG participates in the solvation sheath of Zn2+, regulating overpotential and inhibiting side reactions; meanwhile, TG inhibits the deterioration of dendrites and modifies the direction of zinc deposition by constructing an adsorbed layer on the zinc anode. Consequently, a Zn‐MnO2 full cell with TG electrolyte exhibited a specific capacity of 124.48 mAh g‐1 after 1000 cycles at a current density of 4 A g‐1. This quantitative regulation for suitable solvation sheath and adsorbed layer on zinc anode, and its easy scalability of the process can be of immediate benefit for the dendrite‐free, high‐performance, and low‐cost energy storage systems.

Engineering an electrostatic field layer for high-rate and dendrite-free Zn metal anodes

“…19 Amongst these, use of an electrolyte additive is considered as a practically promising method because it avoids complex preparation, high manufacturing cost, and excessive mass. [20][21][22][23][24][25][26][27][28][29][30] Chen et al used saccharin as an electrolyte additive to induce homogeneous Zn deposition through electrical double-layer regulation and ionic diffusion constraint. 23 Wang et al used dimethyl sulfoxide instead of water molecules in a Zn 2+ solvation sheath that suppressed the solvated water molecule splitting.…”

Interface regulation of the Zn anode by using a low concentration electrolyte additive for aqueous Zn batteries

“…1j and Table S1,† we summarize and compare the cycling stability of Zn anodes with representative electrolyte additives. 24–32 A low additive content of 0.1 m ASA (1.7 wt% relative to H 2 O) presents superior effects on Zn under various testing conditions.…”

Fluorinated Interface Engineering toward Controllable Zinc Deposition and Rapid Cation Migration of Aqueous Zn‐Ion Batteries

“…To tackle the above challenges and ameliorate the reversibility of Zn anode in aqueous electrolytes, tremendous efforts have been exerted. In recent years, various additives such as tripropylene glycol (TG), [11] polydiallyl dimethylammonium chloride (PDD), [12] and aromatic molecules [13] have been studied to get stable Zn anode. Besides, using gel electrolyte, such as polyvinyl alcohol-based water-organic hybrid gel electrolyte, [14] poly(vinyl alcohol)/zinc trifluoromethanesulfonate (PVA/Zn(CF 3 SO 3 ) 2 ) hydrogel electrolyte, [15] and amphoteric cellulose-based double-network, [16] is also an effective solution to the dendrite growth and hydrogen evolution problems.…”