Premium
Suppression of Water Absorption by Molecular Design of Ionic Liquid Electrolyte for Li–Air Battery
Author(s) -
Thomas Morgan L.,
Oda Yoshiki,
Tatara Ryoichi,
Kwon HoiMin,
Ueno Kazuhide,
Dokko Kaoru,
Watanabe Masayoshi
Publication year - 2017
Publication title -
advanced energy materials
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 10.08
H-Index - 220
eISSN - 1614-6840
pISSN - 1614-6832
DOI - 10.1002/aenm.201601753
Subject(s) - electrolyte , materials science , ionic liquid , moisture , battery (electricity) , relative humidity , oxygen , electrochemistry , chemical engineering , inorganic chemistry , oxygen evolution , absorption (acoustics) , electrode , chemistry , organic chemistry , catalysis , composite material , thermodynamics , power (physics) , physics , engineering
In this study, the effect of water on the oxygen reduction reaction is initially investigated in aprotic ionic liquids by cyclic voltammetry, revealing that the presence of water significantly deteriorates the reversibility of the oxygen reduction reaction and oxygen evolution reaction, which will be detrimental to performance of a practical lithium–air battery. In order to prevent moisture intrusion from ambient air, a hydrophobic electrolyte is then designed and the moisture content in the electrolyte exposed to ambient air is greatly suppressed, to less than 1 wt% at 30 °C and 90% RH (relative humidity). Charge and discharge tests using the hydrophobic electrolyte are reversible for several cycles even in O 2 with a RH of 28%. This approach for enhancing the hydrophobicity of the electrolyte, and thus the inherent equilibrium moisture content, for the Li–air battery demonstrates the possibility for improved stability to ambient moisture.