A long cycle-life Na-Mg hybrid battery with a chlorine-free electrolyte based on Mg(TFSI)2. (10th September 2018)

• Record Type: Journal Article
• Authors: Zeng, Jing; Cao, Zulai; Yang, Yang; Wang, Yunhui; Peng, Yueying; Zhang, Yiyong; Wang, Jing; Zhao, Jinbao
• Is Part Of: Electrochimica acta. Volume 284(2018)
• Page Start: 1
• Page End: 9
• Publication Date: 2018-09-10
• Subjects: Na-Mg hybrid batteries -- Mg(TFSI)2 -- Chlorine-free -- Excellent electrochemical performance; Electrochemistry -- Periodicals; Electrochemistry, Industrial -- Periodicals; 541.37
• DOI: 10.1016/j.electacta.2018.07.111
• Languages: English
• ISSNs: 0013-4686

Abstract

Abstract: The commercial applications of rechargeable magnesium batteries (RMBs) are hindered by the slow diffusion kinetic of Mg 2+ ions in cathode materials. To overcome this problem, we design a new Na-Mg hybrid battery with the NaTi2 (PO4 )3 @Carbon (NTP@C) nanoparticles as a cathode material, the Mg metal as an anode and the Mg(TFSI)2 + NaBH4 - triglyme/1, 2-Dimethoxyethane (DME) as a hybrid electrolyte. For the first time, the Mg(TFSI)2 is applied as a Mg 2+ ions source in the chlorine-free Na-Mg hybrid electrolyte with NaBH4 as both Na + ions source and moisture scavenger. The NTP@C/Mg hybrid battery shows excellent electrochemical performance. The corresponding average capacity decay after 1000 cycles is only 0.004% and 0.008% per cycle at 2 C and 10 C, respectively. Even at 20 C, about 60 mAh g −1 can be obtained after 26000 cycles. The impressive capacity retention of 93.7% and 90.2% can be obtained at 5 and 10 C, respectively. The excellent electrochemical performance of the hybrid battery confirms the feasibility using Mg(TFSI)2 in the chlorine-free hybrid electrolyte for long term cycle. The developed NTP@C/Mg hybrid battery possesses the advantages of excellent electrochemical performances, good safety and low cost, making it promising for the commercial applications, especially for the large-scale energy storages. Graphical abstract: Image 1 Highlights: A new chlorine-free Na-Mg hybrid electrolyte based on Mg(TFSI)2 has been developed for the first time. The NTP@C/Mg hybrid battery shows excellent cycling stability and rate ability. The NTP@C/Mg hybrid battery exhibits a long cycle life of 26000 cycles at 20 C.