电池材料LiNi_(0.7)Mn_(0.3)O_2在熔盐中的生长与电化学性能

以NaCl为熔剂,采用熔盐法制备了锂离子正极材料LiNi_(0.7)Mn_(0.3)O_2,通过X射线衍射光谱法(XRD)、扫描电子显微镜法(SEM)及充放电曲线测试对材料结构、形貌以及对应的电化学性能进行了表征。结果表明:在熔盐与产物摩尔比例为4,温度850℃下保温8 h时,可得到晶格发育较好、阳离子混排度低的正极材料,该材料在2.75~4.2 V电压范围内0.2 C充放电,首次放电比容量达180 m Ah/g左右,循环50次后,比容量约保持在160 m Ah/g。而850℃下保温6 h合成的材料晶粒较小但不均匀,具有最大的首次放电比容量,其放电平台较窄,应用受限。

Research of growth and characterization of powder LiNi0.7Mn0.3O2 in molten salt

The compound LiNi0.7Mn0.3O2 was successfully prepared by molten salt synthesis route using NaCI.They were characterized by X-ray diffraction,SEM,and the charge-discharge cycling.The results show that the sample synthesizing at 850 ℃ for 8 h,the lattice of the sample developed more complete,and the cationic mixed degree was low,so it still had the good electrochemical performance.In initial charge-discharge,the discharge specific capacity could be up to about 180 mAh/g in 2.75 V to 4.2 V voltage range in 0.2 C current and contained 160 mAh/g after 50 cycle times.But for 6 h in the molten salt R=4 at 850 ℃ had the greatest discharge specific capacity,but the platform was narrow and limited application.