In:
Batteries & Supercaps, Wiley, Vol. 4, No. 12 ( 2021-12), p. 1830-1842
Abstract:
The influence of ethylenediaminetetraacetic acid (EDTA) electrolyte additive on the performance of Zn−air batteries with near‐neutral chloride‐based electrolytes was examined for primary and secondary batteries. The electrochemical measurements indicated that Zn is not completely active in neat 2 M NaCl, but still could be discharged up to 1 mA cm −2 around −1.0 V Ag/AgCl . The characterization of the Zn surfaces revealed the existence of a passive film consisting of Simonkolleite, Zn(OH) 2 , and/or ZnO. The EDTA additive enhanced the discharge voltages by 200 mV to −1.2 V Ag/AgCl indicating an active Zn surface. The effect of EDTA is explained by its chelation abilities with Zn 2+ before formation of hydroxide or oxide species. The Zn−air cells with EDTA were operated up to 930 h with specific energies up to 840 Wh kg Zn −1 . The cells could also be cycled up to 70 cycles while providing enhanced discharge voltages at 1.15 V over 50 cycles. The positive effect of EDTA is dependent on the amount of free EDTA molecules. Nevertheless, the Zn−air cells showed better performance in terms of higher discharge voltage, discharge energies, and lower overpotentials in presence of EDTA.
Type of Medium:
Online Resource
ISSN:
2566-6223
,
2566-6223
DOI:
10.1002/batt.202100116
Language:
English
Publisher:
Wiley
Publication Date:
2021
detail.hit.zdb_id:
2897248-X