21 Dec 2019, our work "Real-Time Observation of Anion Reaction in High Performance Al Ion Batteries" has been accepted on ACS Applied Materials & Interfaces
Tien-Sheng Lee,1# Shivaraj B. Patil,1# Yu-Ting Kao,1# Ji-Yao An,1 Yi-Cheng Lee,1 Ying-Huang Lai,1 Chung-Kai Chang,2 Yu-Song Cheng,2 Yu-Chun Chuang,2 Hwo-Shuenn Sheu,2 Chun-Hsing Wu,3 Chang-Chung Yang,3 Ruey-Hwa Cheng,4 Chung-Yu Lee,4 Po-Yang Peng,4 Liang-Hsun Lai,4 Hsin-Hung Lee,4 Di-Yan Wang1*
Recently, aluminum ion batteries (AIBs) have attracted great attention across the globe by virtue of its massive gravimetric and volumetric capacities in addition to its high abundance. Though carbon derivatives are excellent cathodes for AIBs, there is much room for further development. In this study, flexuous graphite (FG) was synthesized by a simple thermal shock treatment and, for the first time, an Al/FG battery was applied as a cathode for AIBs to reveal the real-time intercalation of AlCl4- into FG with high flexibility using in situ scanning electron microscope (SEM) measurements exclusively. Similarly, in situ X-ray diffraction (XRD) and in situ Raman techniques have been used to understand the anomalous electrochemical behavior of FG. It was found that FG adopts a unique integrated intercalation–adsorption mechanism where it follows an intercalation mechanism potential above 1.5 V and an adsorption mechanism potential below 1.5 V. This unique integrated intercalation–adsorption mechanism allows FG to exhibit superior properties, like high capacity (≥140 mAh/g), remarkable long-term stability (over 8000 cycles), excellent rate retention (93 mAh/g at 7.5 A/g) and extremely rapid charging and slow discharging.