Vanadium Electrolyte for All-Vanadium Redox-Flow Batteries: The Effect of the Counter Ion

被引：50

作者：

Roznyatovskaya, Nataliya ^{[1
,2
]}

Noack, Jens ^{[1
,2
]}

Mild, Heiko ^{[1
]}

Fuehl, Matthias ^{[1
]}

Fischer, Peter ^{[1
,2
]}

Pinkwart, Karsten ^{[1
,2
]}

Tuebke, Jens ^{[1
,2
]}

Skyllas-Kazacos, Maria ^{[2
,3
]}

机构：

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

[2] UNSW, Mech & Mfg Engn, German Australian Alliance Electrochem Technol St, UNSW Sydney, Sydney, NSW 2052, Australia

[3] UNSW, Mech & Mfg Engn, UNSW Sydney, Sydney, NSW 2052, Australia

来源：

BATTERIES-BASEL | 2019年 / 5卷 / 01期

关键词：

vanadium redox-flow battery; electrolyte; vanadium redox reactions; electrolyte stability; POSITIVE HALF-CELL; DENSITY; V(III);

D O I：

10.3390/batteries5010013

中图分类号：

O646 [电化学、电解、磁化学];

学科分类号：

081704 ;

摘要：

In this study, 1.6 M vanadium electrolytes in the oxidation forms V(III) and V(V) were prepared from V(IV) in sulfuric (4.7 M total sulphate), V(IV) in hydrochloric (6.1 M total chloride) acids, as well as from 1:1 mol mixture of V(III) and V(IV) (denoted as V3.5+) in hydrochloric (7.6 M total chloride) acid. These electrolyte solutions were investigated in terms of performance in vanadium redox flow battery (VRFB). The half-wave potentials of the V(III)/V(II) and V(V)/V(IV) couples, determined by cyclic voltammetry, and the electronic spectra of V(III) and V(IV) electrolyte samples, are discussed to reveal the effect of electrolyte matrix on charge-discharge behavior of a 40 cm(2) cell operated with 1.6 M V3.5+ electrolytes in sulfuric and hydrochloric acids. Provided that the total vanadium concentration and the conductivity of electrolytes are comparable for both acids, respective energy efficiencies of 77% and 72-75% were attained at a current density of 50 mA center dot cm(-2). All electrolytes in the oxidation state V(V) were examined for chemical stability at room temperature and +45 degrees C by titrimetric determination of the molar ratio V(V):V(IV) and total vanadium concentration.

引用

页数：16

共 27 条

[1]

[Anonymous], 1998, ACS SYM SER, DOI [DOI 10.1021/BK-1998-0711.CH001, 10.1021/bk-1998-0711.ch001]

[2] The Electronic Structure of the Vanadyl Ion [J].