Improving zinc porous electrode for secondary alkaline batteries: Toward a simple design of optimized 3D conductive network current collector

JOURNAL OF POWER SOURCES

卷:450

Article

Caldeira, Vincent^1,2  Thiel, Julien²  Lacoste, Francois Rene²  Dubau, Laetitia¹  Chatenet, Marian¹ 

[1] Univ Grenoble Alpes, Univ Savoie Mt Blanc, Grenoble INP, LEPMI,CNRS,Inst Engn, F-38000 Grenoble, France

[2] EASYL SA, 712 Ave Faucigny, F-74130 Bonneville, France

关键词: Zinc-Nickel (Zn / Ni) batteries;    Multilayer current collector;    Migration control;    Core-shell mechanism;   

DOI  :  10.1016/j.jpowsour.2019.227668

来源: Elsevier

【 摘 要 】

The internal migration of zinc within the thickness of porous composite negative electrodes for rechargeable zinc batteries causes detrimental shape change of the zinc electrode. It depends on various parameters linked to the electron conduction in the electrode: electronic percolation, conductive additives, primary current collector. This study highlights a simple solution, that drastically enhances the electrochemical performance of thick and porous zinc electrodes, by rethinking their architecture. Using a multiplicity of thin current collectors enables to create a 3D network of electronic percolation and a better repartition of the current lines within the electrode; as a result, the formation of multiple active zinc cores in the electrode volume is better controlled. This strategy allows to improve the management of zinc migration within the electrode structure, leading to minimal densification of each zinc core, and overall enables higher reversibility of zinc oxidation/reduction upon discharge/charge. It finally mitigates the initial drastic capacity fading observed on standard type calcium zincate negative electrode.

【 授权许可】

Free