A flexible supercapacitor with high capacitance retention at an ultra-low temperature of -65.0°C. (20th August 2022)

• Record Type: Journal Article
• Authors: Zheng, Hengyu; Guan, Ruihua; Liu, Qingxiao; Ou, KangTai; Li, Dian-sen; Fang, Jiang; Fu, Qiang; Sun, Youyi
• Is Part Of: Electrochimica acta. Volume 424(2022)
• Publication Date: 2022-08-20
• Subjects: PANI nanofiber -- Anti-freezing organo-hydrogel -- Supercapacitors -- Ultra-low temperatures -- Capacitance retention; Electrochemistry -- Periodicals; Electrochemistry, Industrial -- Periodicals; 541.37
• DOI: 10.1016/j.electacta.2022.140644
• Languages: English
• ISSNs: 0013-4686

Abstract

Abstract: A novel anti-freezing organo-hydrogel electrolyte is developed to improve capacitance retention of flexible supercapacitor at the ultra-low temperature. The electrolyte is composed of graphene/polyvinyl alcohol matrix and methyl sulfoxide/water/sulfuric acid mixture. It simultaneously possesses a high tensile strength of ca.2.58 MPa and a high ionic conductivity of ca.3.9 S/m. Furthermore, the electrolyte can still maintain high flexibility and high ionic conductivity (ca.1.0S/m) at -65℃. In addition, a flexible supercapacitor with sandwich structure was assembled from the organo-hydrogel electrolyte and two polyaniline fiber/carbon cloth electrodes. The supercapacitor exhibits a high specific capacitance of 252.0F/g and excellent capacitance retention of 93% at -65℃. The excellent capacitance retention is attributed to the synergistic effect of methyl sulfoxide, concentrated sulfuric acid and graphene nanosheets. This study provides a new way to design and prepare anti-freezing electrolyte with high-performance for application in the flexible solid-state electrochemical energy storage at ultra-low temperatures.