Systematic Study of Quaternary Ammonium Cations for Bromine Sequestering Application in High Energy Density Electrolytes for Hydrogen Bromine Redox Flow Batteries

被引：19

作者：

Kuttinger, Michael ^{[1
,2
]}

Loichet Torres, Paulette A. ^{[1
]}

Meyer, Emeline ^{[1
]}

Fischer, Peter ^{[1
]}

Tuebke, Jens ^{[1
,2
]}

机构：

[1] Fraunhofer Inst Chem Technol, Appl Electrochem, Joseph von Fraunhofer Str 7, D-76327 Pfinztal, Germany

[2] Karlsruhe Inst Technol, Inst Mech Proc Engn & Mech, Str Forum 8, D-76131 Karlsruhe, Germany

来源：

MOLECULES | 2021年 / 26卷 / 09期

关键词：

electrochemistry; bromine; quaternary ammonium salts; sequestration; hydrogen bromine redox flow battery; electrolyte; liquid; liquid phase equilibrium; TEMPERATURE IONIC LIQUID; RAMAN-SPECTRA; VIBRATIONAL-SPECTRA; COMPLEXING AGENTS; ADDITIVES; PHASE; PYRROLIDINIUM; MONOANIONS; CONSTANTS; EXISTENCE;

D O I：

10.3390/molecules26092721

中图分类号：

Q5 [生物化学]; Q7 [分子生物学];

学科分类号：

071010 ; 081704 ;

摘要：

Bromine complexing agents (BCAs) are used to reduce the vapor pressure of bromine in the aqueous electrolytes of bromine flow batteries. BCAs bind hazardous, volatile bromine by forming a second, heavy liquid fused salt. The properties of BCAs in a strongly acidic bromine electrolyte are largely unexplored. A total of 38 different quaternary ammonium halides are investigated ex situ regarding their properties and applicability in bromine electrolytes as BCAs. The focus is on the development of safe and performant HBr/Br-2/H2O electrolytes with a theoretical capacity of 180 Ah L-1 for hydrogen bromine redox flow batteries (H-2/Br-2-RFB). Stable liquid fused salts, moderate bromine complexation, large conductivities and large redox potentials in the aqueous phase of the electrolytes are investigated in order to determine the most applicable BCA for this kind of electrolyte. A detailed study on the properties of BCA cations in these parameters is provided for the first time, as well as for electrolyte mixtures at different states of charge of the electrolyte. 1-ethylpyridin-1-ium bromide [C2Py]Br is selected from 38 BCAs based on its properties as a BCA that should be focused on for application in electrolytes for H-2/Br-2-RFB in the future.

引用

页数：26