Affiliation:
1. Key Laboratory of Advanced Materials Technologies International (HongKong Macao and Taiwan) Joint Laboratory on Advanced Materials Technologies College of Materials Science and Engineering Fuzhou University Fuzhou 350108 P. R. China
2. Engineering Research Center of Polymer Green Recycling of Ministry of Education College of Environmental and Resource Sciences Fujian Normal University Fuzhou Fujian 350007 P. R. China
3. Key Laboratory of Organic Optoelectronics & Molecular Engineering Ministry of Education Department of Chemistry Tsinghua University Beijing 100084 P. R. China
4. Fujian Science & Technology Innovation Laboratory for Optoelectronic Information of China Fuzhou Fujian 350108 P. R. China
5. National Laboratory of Solid State Microstructures Department of Physics Nanjing University Nanjing 210093 P. R. China
Abstract
AbstractOwing to zinc dendrites and parasitic reactions, aqueous Zn‐metal batteries often suffer from poor reversibility and cyclability. Electrolyte additives present a promising strategy to improve Zn anode stability. However, the ever‐evolving perspectives and mechanisms, paradoxically, complicate battery design, causing a scenario where any electrolyte additive seems to be effective. Herein, it is taken ionic liquid (IL) additives as an example and detailed explored the impact of three typical IL anions, namely OTF−, TFA−, and BF4−. It is identified that the primary determinant of electrolyte additives as their electrical double layer (EDL) structures and their subsequent solid‐electrolyte interface (SEI) composition. An advantageous EDL structure, akin to an ion‐shield, can reduce the absorption of H2O molecules, which further enrich the SEI with zincophilic and hydrophobic components, thereby mitigating parasitic reactions and Zn dendrite formation. As a result, the Zn||Zn cell with optimal [EMIM]OTF additives demonstrates an exceptional cycling life under challenging conditions, its cumulative plated capacity surpasses most previously reported results by utilizing different IL additives. This work extends beyond performance enhancements, representing a valuable exploration of key criteria for electrolyte additives is believed. These insights are expected to offer fundamental guidance for future research and electrolyte design.
Funder
National Natural Science Foundation of China
National Key Laboratory of Aerodynamic Design and Research
Natural Science Foundation of Fujian Province
Fujian Science and Technology Innovation Laboratory for Optoelectronic Information of China
Subject
Electrochemistry,Condensed Matter Physics,Biomaterials,Electronic, Optical and Magnetic Materials