Abstract
Physico-chemical properties of NaOH and KOH electrolytes are studied as possible state of charge indicators for the alkaline zinc-air redox flow battery. In order to predict the available energy of the battery and to prevent degradation as the result of unsuitable operating conditions, its state of charge has to be known. The state of charge is directly related to the composition of the negative electrolyte. A battery charging operation is simulated by electrodepositing zinc on a rotating cylinder electrode from NaOH electrolyte, while the simulation of a discharging operation is accomplished by dissolving ZnO in KOH electrolyte. The refractive index, conductivity, and density of NaOH- and KOH-electrolytes as well as the rest potential of the zinc electrode in these media are measured for different zincate and alkali concentrations at several temperatures. The electrolyte density and electrolyte conductivity are both linearly correlated with the zincate concentration. A linear correlation is found also between the rest potential and the logarithmic concentration term in the Nernst equation for the zinc half-cell reaction. These indicators permit a simple and straightforward monitoring of the state of charge of alkaline zinc-air redox flow batteries.
| Original language | English |
|---|---|
| Pages (from-to) | 76-81 |
| Number of pages | 6 |
| Journal | Journal of power sources |
| Volume | 424 |
| DOIs | |
| Publication status | Published - 1 Jun 2019 |
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Keywords
- Conductivity
- Density
- Redox flow battery
- Rest potential
- State of charge
- Zincate electrolyte
ASJC Scopus subject areas
- Renewable Energy, Sustainability and the Environment
- Energy Engineering and Power Technology
- Physical and Theoretical Chemistry
- Electrical and Electronic Engineering
Fields of Expertise
- Advanced Materials Science
Treatment code (Nähere Zuordnung)
- Experimental
Cite this
State of charge indicators for alkaline zinc-air redox flow batteries. / Zelger, Christian; Süßenbacher, Michael; Laskos, Andreas; Gollas, Bernhard.
In: Journal of power sources, Vol. 424, 01.06.2019, p. 76-81.Research output: Contribution to journal › Article › Research › peer-review
}
TY - JOUR
T1 - State of charge indicators for alkaline zinc-air redox flow batteries
AU - Zelger, Christian
AU - Süßenbacher, Michael
AU - Laskos, Andreas
AU - Gollas, Bernhard
PY - 2019/6/1
Y1 - 2019/6/1
N2 - Physico-chemical properties of NaOH and KOH electrolytes are studied as possible state of charge indicators for the alkaline zinc-air redox flow battery. In order to predict the available energy of the battery and to prevent degradation as the result of unsuitable operating conditions, its state of charge has to be known. The state of charge is directly related to the composition of the negative electrolyte. A battery charging operation is simulated by electrodepositing zinc on a rotating cylinder electrode from NaOH electrolyte, while the simulation of a discharging operation is accomplished by dissolving ZnO in KOH electrolyte. The refractive index, conductivity, and density of NaOH- and KOH-electrolytes as well as the rest potential of the zinc electrode in these media are measured for different zincate and alkali concentrations at several temperatures. The electrolyte density and electrolyte conductivity are both linearly correlated with the zincate concentration. A linear correlation is found also between the rest potential and the logarithmic concentration term in the Nernst equation for the zinc half-cell reaction. These indicators permit a simple and straightforward monitoring of the state of charge of alkaline zinc-air redox flow batteries.
AB - Physico-chemical properties of NaOH and KOH electrolytes are studied as possible state of charge indicators for the alkaline zinc-air redox flow battery. In order to predict the available energy of the battery and to prevent degradation as the result of unsuitable operating conditions, its state of charge has to be known. The state of charge is directly related to the composition of the negative electrolyte. A battery charging operation is simulated by electrodepositing zinc on a rotating cylinder electrode from NaOH electrolyte, while the simulation of a discharging operation is accomplished by dissolving ZnO in KOH electrolyte. The refractive index, conductivity, and density of NaOH- and KOH-electrolytes as well as the rest potential of the zinc electrode in these media are measured for different zincate and alkali concentrations at several temperatures. The electrolyte density and electrolyte conductivity are both linearly correlated with the zincate concentration. A linear correlation is found also between the rest potential and the logarithmic concentration term in the Nernst equation for the zinc half-cell reaction. These indicators permit a simple and straightforward monitoring of the state of charge of alkaline zinc-air redox flow batteries.
KW - Conductivity
KW - Density
KW - Redox flow battery
KW - Rest potential
KW - State of charge
KW - Zincate electrolyte
UR - http://www.scopus.com/inward/record.url?scp=85063489681&partnerID=8YFLogxK
U2 - 10.1016/j.jpowsour.2019.03.099
DO - 10.1016/j.jpowsour.2019.03.099
M3 - Article
VL - 424
SP - 76
EP - 81
JO - Journal of power sources
JF - Journal of power sources
SN - 0378-7753
ER -