Effect of Stannum Ion on the Enhancement of the Charge Retention of Single-Flow Zinc-Nickel Battery

• Published in: Journal of the Electrochemical Society 2019, Vol.166 (10), p.A1813-A1818
• Main Authors: Shou-guang, Yao, Yong, Chen, Jie, Cheng, Ya-ju, Shen, Da-pei, Ding
• Format: Article
• Language: English
• ISSN: 0013-4651; 1945-7111
• DOI: 10.1149/2.0311910jes

This study aims to discuss the effect of stannum ion (potassium stannate) in alkaline zincate solution on the deposition/dissolution behavior of zinc anode for single-flow zinc-nickel battery (SFZNB). Physical analysis is conducted using scanning electron microscopy and energy dispersive X-ray spectroscopy (EDS) technologies. The electrochemical performance of the battery is tested using cyclic voltammetry and galvanostatic techniques. Results show that adding potassium stannate in alkaline solution promotes crystal seed formation and grain growth and substantially improves the charge retention of the battery. The battery is charged to 18.75 mAh·cm−2 (based on the area of the electrode) at current density of 10 mA·cm−2 and set aside for 12 h. Then, the battery using electrolyte with 0.1 mol·L−1 potassium stannate has a discharge capacity of 15.20 mAh·cm−2 (coulomb efficiency of 81.1%). Moreover, the control sample has a discharge capacity of 11.25 mAh·cm−2 (coulomb efficiency of 60.0%). Thus, the present work provides a simple approach to restrain the SFZNB from self-discharge.