A High-Energy-Density Potassium Battery with a Polymer-Gel Electrolyte and a Polyaniline Cathode

作者：Gao, Hongcai; Xue, Leigang; Xin, Sen; Goodenough, John B.^*

来源：Angewandte Chemie - International Edition, 2018, 57(19): 5449-5453.

DOI：10.1002/anie.201802248

• cathode materials
• polyaniline
• polymer electrolytes
• potassium batteries
• potassium metal anodes

A safe, rechargeable potassium battery of high energy density and excellent cycling stability has been developed. The anion component of the electrolyte salt is inserted into a polyaniline cathode upon charging and extracted from it during discharging while the K+ ion of the KPF6 salt is plated/stripped on the potassium-metal anode. The use of a p-type polymer cathode increases the cell voltage. By replacing the organic-liquid electrolyte in a glass-fiber separator with a polymer-gel electrolyte of cross-linked poly(methyl methacrylate), a dendrite-free potassium anode can be plated/stripped, and the electrode/electrolyte interface is stabilized. The potassium anode wets the polymer, and the cross-linked architecture provides small pores of adjustable sizes to stabilize a solid-electrolyte interphase formed at the anode/electrolyte interface. This alternative electrolyte/cathode strategy offers a promising new approach to low-cost potassium batteries for the stationary storage of electric power.

• 出版日期2018-5-4