Aqueous Mg-Ion Battery Based on Polyimide Anode and Prussian Blue Cathode

• Published in: ACS energy letters Vol. 2; no. 5; pp. 1115 - 1121
• Main Authors: Chen, L, Bao, J. L, Dong, X, Truhlar, D. G, Wang, Y, Wang, C, Xia, Y
• Format: Journal Article
• Language: English
• Published: United States American Chemical Society 12.05.2017; American Chemical Society (ACS)
• Subjects: Chemistry; Electrochemistry; Energy & Fuels; Materials Science; Science & Technology - Other Topics
• ISSN: 2380-8195; 2380-8195
• DOI: 10.1021/acsenergylett.7b00040

The magnesium-metal battery, which consists of a cathode, a Mg-metal anode, and a nonaqueous electrolyte, is a safer and less expensive alternative to the popular Li-ion battery. However, the performance of Mg batteries is greatly limited by the low electrochemical oxidative stability of nonaqueous electrolytes, the slow Mg2+ diffusion into the cathode, and the irreversibility of Mg striping and plating on the Mg metal anode. Here, we report the first Mg-ion battery using a Mg2+ aqueous electrolyte, nickel hexacyanoferrate cathode, and polyimide anode. The operation depends on Mg2+ intercalation–deintercalation at the cathode and reversible enolization at the anode, accompanied by Mg2+ transport between cathode and anode. The cell exhibits a maximum cell voltage of 1.5 V and a supercapacitor-like high power, and it can be cycled 5000 times. This system points the way to improved Mg-based rechargeable batteries.