Novel Graphitic Sheets with Ultralong Cycling, Ultrafast Rate, and High Capacity for Sodium Storage
Jiale Wan, Sicheng Fan, Jiakang Qu, Pin Du, Jinxia Wang, Qiushi Song, Zhiqiang Ning, Kai Yu, Huayi Yin, Hongwei Xie
Abstract
Achieving fast energy storage at high power levels from sodium-ion batteries (SIBs) is essential for terawatt-hour (TWh) supply/storage. Designing and preparing electrode materials to meet ultrafast rates is a necessity. Herein, we design and synthesize a graphitic sheet (GS) anode material with abundant structural defects and mesopores by a low-temperature, simple, and short-flow method using calcium carbide (CaC 2 ) and CCl 4 feedstocks. The GSs are of 20–130 nm in thickness and several micrometers in width, which support a fast charge transfer rate for [Na-diglyme] + and a high storage capacity. After annealing, the treated GSsH500 exhibits a fast rate performance (23 s), a long cycle stability (40 000 cycles), and a high Coulomb efficiency (99.95%) by pseudocapacitive process. These findings provide new highlights for designing high-capacity, long-life graphite anode materials of SIBs for grid-scale energy storage.