Scalable high-voltage Zn||MnO2 batteries achieved by mild amphiphilic hydrogel electrolytes

• 成果类型: Article
• 署名作者: Li, Chuan; Liang, Bochun; Chen, Ze; Zhang, Rong; Cui, Huilin; Wang, Yanbo; Li, Qing; Peng, Chao; Fan, Jun; Pei, Zengxia; Zhi, Chunyi
• 署名单位: City University of Hong Kong; Chinese Academy of Sciences; Shenzhen Institute of Advanced Technology, CAS; University of Sydney; City University of Hong Kong; City University of Hong Kong; University of Hong Kong
• 刊物名称: PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA
• ISSN/ISSBN: 0027-14983
• DOI: 10.1073/pnas.2501935122
• 发表日期: 2025-08-15
• 关键词: water; DYNAMICS; coatings; ion

摘要

The practical applications of aqueous Zn vertical bar vertical bar MnO2 batteries are limited by their small areal capacity, low discharging plateau, and clumsy packing device. Currently, the high potential MnO2/Mn2+ redox conversion can only be well activated in electrolytes with a very low pH value, which is not friendly to the Zn metal anode. To overcome these limitations, we have designed mild amphiphilic hydrogel electrolytes (AHEs) with a wide electrochemical stability window (ESW) and high ionic activity. The design is based on the mechanism that trace amounts of hydrophobic moieties enhance the hydrogen bonding between hydrophilic groups and water molecules in the hydrogel electrolytes. The developed AHE possesses an ESW up to similar to 3.0 V even at a high water content of similar to 76 wt%. The assembled Zn vertical bar vertical bar MnO2 pouch cells using the hydrogel electrolytes demonstrated a large areal capacity of similar to 5 mAh cm(-2) at 1 mA cm(-2) and a high-voltage and flat discharging plateau of similar to 1.9 V. Furthermore, a pouch cell with an area of 40 cm(2) was fabricated, exhibiting a capacity of similar to 125 mAh at 2 mA cm(-2). Two pouch cells (25 cm(2)) in series were used to drive a 3.7 V-powerable electric fan. This work highlights the rational design of wide-ESW AHEs with high ionic activity as a promising approach to achieving portable and scalable applications of aqueous high-voltage Zn vertical bar vertical bar MnO2 batteries.