Stable Conversion Chemistry‐Based Lithium Metal Batteries Enabled by Hierarchical Multifunctional Polymer Electrolytes with Near‐Single Ion Conduction

• Published in: Angewandte Chemie International Edition Vol. 58; no. 18; pp. 6001 - 6006
• Main Authors: Zhou, Dong, Tkacheva, Anastasia, Tang, Xiao, Sun, Bing, Shanmukaraj, Devaraj, Li, Peng, Zhang, Fan, Armand, Michel, Wang, Guoxiu
• Format: Journal Article
• Language: English
• Published: Germany Wiley Subscription Services, Inc 23.04.2019
• Edition: International ed. in English
• Subjects: Batteries; Conduction; Copolymerization; Dendrites; Dendritic structure; Electrolytes; Glass fibers; hierarchical structure; Iodine; iodine cathode; Ion currents; Ions; Lithium; Lithium batteries; lithium metal battery; Mechanical properties; Monomers; near-single ion conduction; Organic chemistry; polymer electrolyte; Polymers; iodine cathode; lithium metal battery; hierarchical structure; polymer electrolyte; near-single ion conduction
• ISSN: 1433-7851; 1521-3773; 1521-3773
• DOI: 10.1002/anie.201901582

The low Coulombic efficiency and serious safety issues resulting from uncontrollable dendrite growth have severely impeded the practical applications of lithium (Li) metal anodes. Herein we report a stable quasi‐solid‐state Li metal battery by employing a hierarchical multifunctional polymer electrolyte (HMPE). This hybrid electrolyte was fabricated via in situ copolymerizing lithium 1‐[3‐(methacryloyloxy)propylsulfonyl]‐1‐(trifluoromethanesulfonyl)imide (LiMTFSI) and pentaerythritol tetraacrylate (PETEA) monomers in traditional liquid electrolyte, which is absorbed in a poly(3,3‐dimethylacrylic acid lithium) (PDAALi)‐coated glass fiber membrane. The well‐designed HMPE simultaneously exhibits high ionic conductivity (2.24×10−3 S cm−1 at 25 °C), near‐single ion conducting behavior (Li ion transference number of 0.75), good mechanical strength and remarkable suppression for Li dendrite growth. More intriguingly, the cation permselective HMPE efficiently prevents the migration of negatively charged iodine (I) species, which provides the as‐developed Li‐I batteries with high capacity and long cycling stability. A novel hierarchical multifunctional polymer electrolyte shows near‐single ion conduction for lithium metal batteries. This electrolyte was in situ fabricated by integrating (LiMTFSI‐PETEA)‐based crosslinking gel polymer electrolyte with PDDALi‐coated glass fiber membrane. The as‐prepared multifunctional electrolyte exhibits high ionic conductivity, enhanced safety, suppression on dendrite growth, and stable cycling in lithium‐iodine batteries.