Development and Characterization of an Electrically Rechargeable Zinc-Air Battery Stack

Energies

Hongyun Ma²  Baoguo Wang¹  Yongsheng Fan²  Weichen Hong² 

[1] Department of Chemical Engineering, Tsinghua University, Beijing 100084, China;

关键词: electrically rechargeable zinc-air battery stack;    oxygen reduction reaction;    oxygen evolution reaction;    polarization;    charge-discharge cycles;   

DOI  :  10.3390/en7106549

来源: mdpi

【 摘 要 】

An electrically rechargeable zinc-air battery stack consisting of three single cells in series was designed using a novel structured bipolar plate with air-breathing holes. Alpha-MnO₂ and LaNiO₃ severed as the catalysts for the oxygen reduction reaction (ORR) and oxygen evolution reaction (OER). The anodic and cathodic polarization and individual cell voltages were measured at constant charge-discharge (C-D) current densities indicating a uniform voltage profile for each single cell. One hundred C-D cycles were carried out for the stack. The results showed that, over the initial 10 cycles, the average C-D voltage gap was about 0.94 V and the average energy efficiency reached 89.28% with current density charging at 15 mA·cm⁻² and discharging at 25 mA·cm⁻². The total increase in charging voltage over the 100 C-D cycles was ~1.56% demonstrating excellent stability performance. The stack performance degradation was analyzed by galvanostatic electrochemical impedance spectroscopy. The charge transfer resistance of ORR increased from 1.57 to 2.21 Ω and that of Zn/Zn²⁺ reaction increased from 0.21 to 0.34 Ω after 100 C-D cycles. The quantitative analysis guided the potential for the optimization of both positive and negative electrodes to improve the cycle life of the cell stack.

【 授权许可】

CC BY   
© 2014 by the authors; licensee MDPI, Basel, Switzerland.