Li_3V_2(PO_4)_3/碳纳米纤维复合材料的制备及其电化学性能研究

Electrospun Li_3V_2(PO_4)_3/Carbon Nanofiber as Cathode Materials for the High-performance Lithium-ion Batteries

通过静电纺丝的方法,制备了磷酸钒锂/碳纳米纤维复合物（LVP/CNF）,经不同温度的高温热处理后,样品形貌虽然发生变化,但仍保持了有序纤维状,且纤维直径随温度升高逐渐变小.通过XRD表征发现600,700,800,900℃下得到样品的结晶度不同,在600℃时没有成相,800℃和900℃时结晶性较好.在3.0~4.3 V的电压范围下,800℃和900℃煅烧得到的LVP样品的首次放电容量为134 m Ah/g和135 m Ah/g,达到了Li_3V_2（PO_4）_3的理论容量133 m Ah/g.在高倍率充放电条件下,LVP/CNF材料仍然显示出优良的电化学性能.

In this paper, a series of Li_3V_2（PO_4）_3/C composite nanofibers is prepared by a facile and environmental-ly friendly electrospinning method and calcined under different temperatures. The LVP nanofiber calcined under900 ℃ exhibits the best electrochemical performance. The bicontinuous morphologies of LVP/CNF are the fibersshrunk and the LVP crystals simultaneously grown. At the range of 3.0~4.3 V, LVP/CNF obtained under 900 ℃delivers the initial capacity of 135 m Ah/g, close to the theoretical capacity of LVP. Even at high current density,the sample of LVP/CNF still presents good electrochemical performance.