Advanced rechargeable aluminium ion battery with a high-quality natural graphite cathode

• Published in: Nature communications Vol. 8; no. 1; p. 14283
• Main Authors: Wang, Di-Yan, Wei, Chuan-Yu, Lin, Meng-Chang, Pan, Chun-Jern, Chou, Hung-Lung, Chen, Hsin-An, Gong, Ming, Wu, Yingpeng, Yuan, Chunze, Angell, Michael, Hsieh, Yu-Ju, Chen, Yu-Hsun, Wen, Cheng-Yen, Chen, Chun-Wei, Hwang, Bing-Joe, Chen, Chia-Chun, Dai, Hongjie
• Format: Journal Article
• Language: English
• Published: London Nature Publishing Group UK 13-02-2017; Nature Publishing Group; Nature Portfolio
• Subjects: 119/118; 140/133; 639/301/299/891; 639/638/675; Batteries; Chemistry; Electrodes; Electrolytes; energy; ENERGY STORAGE; Graphite; Humanities and Social Sciences; MATERIALS SCIENCE; multidisciplinary; Science; Science (multidisciplinary); Taiwan
• ISSN: 2041-1723; 2041-1723
• DOI: 10.1038/ncomms14283

Recently, interest in aluminium ion batteries with aluminium anodes, graphite cathodes and ionic liquid electrolytes has increased; however, much remains to be done to increase the cathode capacity and to understand details of the anion–graphite intercalation mechanism. Here, an aluminium ion battery cell made using pristine natural graphite flakes achieves a specific capacity of ∼110 mAh g
−1
with Coulombic efficiency ∼98%, at a current density of 99 mA g
−1
(0.9 C) with clear discharge voltage plateaus (2.25–2.0 V and 1.9–1.5 V). The cell has a capacity of 60 mAh g
−1
at 6 C, over 6,000 cycles with Coulombic efficiency ∼ 99%. Raman spectroscopy shows two different intercalation processes involving chloroaluminate anions at the two discharging plateaus, while C–Cl bonding on the surface, or edges of natural graphite, is found using X-ray absorption spectroscopy. Finally, theoretical calculations are employed to investigate the intercalation behaviour of choloraluminate anions in the graphite electrode.
Rechargeable aluminium ion batteries are an emerging class of energy storage device. Here the authors reveal high-quality natural graphite as a promising cathode for Al-ion batteries, also identifying chloroaluminate anion intercalation in graphite by Raman spectroscopy.