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

作者：Zeng, Jing; Cao, Zulai; Yang, Yang; Wang, Yunhui; Peng, Yueying; Zhang, Yiyong; Wang, Jing^*; Zhao, Jinbao^*

来源：Electrochimica Acta, 2018, 284: 1-9.

DOI：10.1016/j.electacta.2018.07.111

• Na-Mg hybrid batteries
• Mg(TFSI)(2)
• Chlorine-free
• Excellent electrochemical performance

The commercial applications of rechargeable magnesium batteries (RMBs) are hindered by the slow diffusion kinetic of Mg2+ 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 Mg2+ ions source in the chlorine-free Na-Mg hybrid electrolyte with NaBH4 as both Na thorn 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.

• 出版日期2018-9-10
• 单位厦门大学