Discharge Performance of Zinc-Air Flow Batteries Under the Effects of Sodium Dodecyl Sulfate and Pluronic F-127

Abstract

Zinc-air batteries are a promising technology for large-scale electricity storage. However, their practical deployment has been hindered by some issues related to corrosion and passivation of the zinc anode in an alkaline electrolyte. In this work, anionic surfactant sodium dodecyl sulfate (SDS) and nonionic surfactant Pluronic F-127 (P127) are examined their applicability to enhance the battery performances. Pristine zinc granules in 7 M KOH, pristine zinc granules in 0–8 mM SDS/7 M KOH, pristine zinc granules in 0–1000 ppm P127/7 M KOH, and SDS coated zinc granules in 7 M KOH were examined. Cyclic voltammograms, potentiodynamic polarization, and electrochemical impedance spectroscopy confirmed that using 0.2 mM SDS or 100 ppm P127 effectively suppressed the anode corrosion and passivation. Nevertheless, direct coating SDS on the zinc anode showed adverse effects because the thick layer of SDS coating acted as a passivating film and blocked the removal of the anode oxidation product from the zinc surface. Furthermore, the performances of the zinc-air flow batteries were studied. Galvanostatic discharge results indicated that the improvement of discharge capacity and energy density could be sought by the introduction of the surfactants to the KOH electrolyte. The enhancement of specific discharge capacity for 30% and 24% was observed in the electrolyte containing 100 ppm P127 and 0.2 mM SDS, respectively.

Three-Dimensional Fibrous Iron as Anode Current Collector for Rechargeable Zinc–Air Batteries

“…The formation of ZnO, on the forward scan, was followed by its precipitation on the electrode surface, thus forming a passive layer which reduced the active area of the electrode. However, the Zn ions which did not oxidize in the forward scan tended to oxidize in the reverse scan, due to the breakdown of the passive layer at the very oxidation potential range [32]. The Zn/IF electrode exhibited a smaller oxidation peak in reverse scan that slightly shifted to negative potentials, suggesting that the passivation film was more stable and less soluble in the presence of the fibrous iron electrode.…”

“…According to CV analysis, the Zn/IF electrode revealed a comparable mechanism of Zn dissolution/deposition with the Zn/NF electrode. Although the surface of Zn/IF is susceptible to corrosion via hydrogen evolution, the impact can be diminished when using additives to the electrolyte solution [32]. Furthermore, the IF electrode displayed a noticeably low charge transfer resistance and, hence, proved to be a preferable substitute to the conventional NF in the synthesis of the porous anode.…”

Silver Decorated Reduced Graphene Oxide as Electrocatalyst for Zinc–Air Batteries

“…As regards air cathode polarization, the zinc-air battery was fabricated using the 0.3 M AgNP/rGO catalyst with different ratios of AgNP/rGO to carbon black: namely, 9:0, 7:2, 5:4 and 3:6. The air-cathode made of MnO 2 to carbon black of 2:7, which is generally used as ORR electrocatalyst [42,43], was also included, as a reference, to compare the performance of the synthesized electrocatalysts. Figure 5a shows the overpotential of the air cathodes.…”

Discharge performance of Zn‐air fuel cells under the influence of Carbopol 940 thickener

“…This problem was partially solved by using a complete gel electrolyte like anionic surfactant sodium dodecyl sulfate (SDS) or nonionic surfactant Pluronic F‐127 that might effectively suppress the anode corrosion and passivation. Galvanostatic discharge results indicated that the improvement of discharge capacity can be achieved by using surfactants to the KOH electrolyte . Implementation of a circulating electrolyte flow system will result in the removal of spent Zn anode, and in the meantime, the Zn fuel can also be continually added to the reaction tank via the flowing electrolyte.…”

“…Galvanostatic discharge results indicated that the improvement of discharge capacity can be achieved by using surfactants to the KOH electrolyte. 7 Implementation of a circulating electrolyte flow system will result in the removal of spent Zn anode, and in the meantime, the Zn fuel can also be continually added to the reaction tank via the flowing electrolyte. The reactant elimination can still be resupplied smoothly without using a mechanical exchange.…”