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Corresponding Author

Li-zhen WANG(wlz@zzuli.edu.cn)

Abstract

In this work, with an aim to improve the performance of spinel lithium manganese and to reduce the safety concern of Li-ion battery system, the effects of N-methyl-N-butylpyrrolidinium bis (trifluoromethylsulfonyl) imide (PyR14TFSI) on performance of electrolyte and spinel lithium manganes are studied by using differential scanning calorimetry (DSC), BTS battery test system, electrochemical work station, X-ray diffraction (XRD), scanning electron microscopy (SEM) and energy dispersive spectroscopy (EDS). The results indicate that the ionic conductivity of electrolyte is increased with the increase of PyR14TFSI concentration. When the concentration of PyR14TFSI is 2.5% (by mass), the DSC curves of the PyR14TFSI containing electrolyte are changed from three strong endothermic peaks (89.3 oC, 201 oC, 224 oC) to two strong endothermic peaks (116.6 oC, 244.3 oC). At 50 oC, the rate capability is enhanced, the discharge capacity is increased by 16 mAh·g-1, and the capacity retention is 88.3% (increased by 2.2%) after cycled for 100 times. PyR14TFSI is beneficial to the stability of the electrode structure.

Graphical Abstract

Keywords

ionic liquids, spinel lithium manganese, PyR14TFSI, safety

Publication Date

2014-02-25

Online Available Date

2014-02-24

Revised Date

2013-03-25

Received Date

2013-01-10

References

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