摘要
对水热法合成的无定形Li-Mn-Me-O前驱体(Me=0、Co或Co-Ti)进行热处理,制备了Co掺杂及Co-Ti复合掺杂的尖晶石型LiMn_2O_4正极材料。通过XRD、SEM对Co-Ti复合掺杂的LiMn_2O_4的结构和微观形貌进行分析与表征,并测试了其电化学性能。研究结果表明:所制备的粉体材料具有良好的立方尖晶石结构,无杂相峰存在;Co-Ti复合掺杂使LiMn_2O_4颗粒变小;其在3.0~4.3 V电压范围内,0.5C倍率条件下,首次放电比容量为116.5 m Ah/g,循环100圈后容量保持率为93.5%;与不掺杂样品相比,其初始容量提高,100次循环的容量保持率提高,且高倍率循环性能也明显得到改善。
Spinel LiMn_2O_4 cathode materials doped with Co and Co-Ti was prepared from the amorphous Li-Mn-MeO precursor(Me = 0、Co or Co-Ti) which was obtained by a hydrodrothermal process with heat treatment.Its structure and morphology were studied by X-ray diffraction(XRD) and the scanning electron microscope(SEM)analysis and the electrochemical performance of the LiMn_2O_4 doped with Co-Ti was studied.The test results indicate that the LiMn_2O_4 doped with Co-Ti is pure spinel phase.Spinel LiMn_2O_4 cathode materials doped with of Co-Ti made its particle size smaller.Electrochemical test results indicate that the LiMn_2O_4 doped with Co-Ti had a capacity of 116.5 m Ah/g over 3.0 V to 4.3 V at 0.5C,reaching a 93.5% capacity retention after 100 cycles.Compared with the pristine material,the LiMn_2O_4 doped with Co-Ti had a higher initial capacity.The high rate capacity and the capacity retention after 100 cycles had been improved.
出处
《中国锰业》
2017年第1期93-96,共4页
China Manganese Industry
基金
广西八桂学者计划(NO.2011A025)
教育部西部之光访问学者计划
关键词
锂离子电池
锰酸锂
Co-Ti复合掺杂
水热处理
Lithium ion batteries
LiMn2O4
complex doping with Co-Ti
Hydrodrothermal process with heat treatment
