Ultrahigh-Strength Ultrahigh Molecular Weight Polyethylene (UHMWPE)-Based Fiber Electrode for High Performance Flexible Supercapacitors

Flexible fiber-based supercapacitor (FSC) with excellent electrochemical performance and high tensile strength and modulus is strongly desired for some special circumstances, such as load-bearing, abrasion resistant, and anticutting fabrics. Here, a series of ultrahigh-strength fiber electrodes are prepared for flexible FSCs based on ultrahigh molecular weight polyethylene fibers, on which the polydopamine, Ag, and poly (3,4-ethylene dioxythiophene): poly(styrenesulfonate) are deposited in sequence. The modified fiber-based electrode exhibits superhigh strength up to 3.72 GPa, which is the highest among fiber-based electrodes reported to date. In addition, FSCs fabricated with the optimized fiber electrode shows a specific areal capacity as high as 563 mF cm(-2) at 0.17 mA cm(-2), which corresponds to a high areal energy density of approximate to 50.1 mu Wh cm(-2) at a power density of approximate to 124 mu W cm(-2). The specific areal capacity only decrease 8% after 1000 times bending test, indicating the outstanding bending performance of this composite fiber electrode. Furthermore, several FSCs can be connected in series or in parallel to get higher working voltage or higher capacity respectively, which demonstrates its potential for broad applications in flexible devices.