Open AccessBoosting the Oxidative Potential of Polyethylene Glycol‐Based Polymer Electrolyte to 4.36 V by Spatially Restricting Hydroxyl Groups for High‐Voltage Flexible Lithium‐Ion Battery Applications
Author(s) -
Fang Zhenhan,
Luo Yufeng,
Liu Haitao,
Hong Zixin,
Wu Hengcai,
Zhao Fei,
Liu Peng,
Li Qunqing,
Fan Shoushan,
Duan Wenhui,
Wang Jiaping
Publication year - 2021
Publication title -
advanced science
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 5.388
H-Index - 100
ISSN - 2198-3844
DOI - 10.1002/advs.202100736
Subject(s) - electrolyte , polyethylene glycol , electrochemistry , materials science , cyclic voltammetry , polymer , lithium (medication) , diglycidyl ether , lithium ion battery , chemical engineering , chemistry , polymer chemistry , epoxy , battery (electricity) , electrode , organic chemistry , composite material , medicine , power (physics) , physics , quantum mechanics , engineering , endocrinology , bisphenol a
Cross‐linked polyethylene glycol‐based resin (c‐PEGR) is constructed by a ring‐opening reaction of polyethylene glycol diglycidyl ether (PEGDE) with epoxy groups and polyether amine (PEA) with amino groups. By confining the hydroxyl groups with inferior oxidative stability to the c‐PEGR backbone, the oxidation potential of the PEG‐based polymer material with reduced reactivity is boosted to 4.36 V. The c‐PEGR based gel electrolyte shows excellent flexibility, lithium‐ion transport, lithium compatibility, and enhanced oxidation stability, and is successfully applied to a 4.35 V lithium cobaltate (LCO)||lithium (Li) battery system. A quasi‐static linear scanning voltammetry (QS‐LSV) method is proposed for the first time to accurately measure the oxidation potential and electrochemical stability window of materials with low conductivities such as polymers, which possesses the advantages of high accuracy and short test time. This work provides new insights and research techniques for selecting polymer electrolytes for high‐voltage flexible lithium‐ion batteries (LIBs).