Ultrafast All‐Solid‐State Coaxial Asymmetric Fiber Supercapacitors with a High Volumetric Energy Density

• DOI: 10.1002/aenm.201702946
• Publication Date: 2018-01-29T21:12:51Z
• Authors: Zhenghui Pan; Jun Zhong; Qichong Zhang; Jie Yang; Yongcai Qiu; Xiaoyu Ding; Kaiqi Nie; Hua Yuan; Kun Feng; Xianshu Wang; Guoguang Xu; Wanfei Li; Yagang Yao; Qinwen Li; Meinan Liu; Yuegang Zhang
• Keywords: Coaxial; Power density

Abstract Fiber‐supercapacitors (FSCs) are promising energy storage devices that can complement or even replace microbatteries in miniaturized portable and wearable electronics. Currently, a major challenge for FSCs is achieving ultrahigh volumetric power densities simultaneously, especially when the charge/discharge rates exceed 1 V s −1 . Herein, an Au‐nanoparticle‐doped‐MnO x @CoNi‐alloy@carbon‐nanotube (Au–MnO @CoNi@CNT) core/shell nanocomposite fiber electrode designed, aiming to boost its rate by taking advantage of superconductive CoNi alloy network greatly enhanced conductivity Au doped MnO active materials. An all‐solid‐state coaxial asymmetric FSC (CAFSC) prototype device made wrapping this with holey graphene paper (HGP) exhibits excellent performance at up 10 , which highest charge demonstrated so far based on pseudocapacitive Furthermore, our fully packaged CAFSC delivers density ≈15.1 mW h cm −3 while simultaneously maintaining high 7.28 W as well long cycle life (90% retention after 000 cycles). This value among all reported FSCs, better than typical 4 V/500 µA thin‐film lithium battery.