葡萄糖对溶胶凝胶法制备Li_(1.2)Ni_(0.13)Co_(0.13)Mn_(0.54)O_2正极材料性能的影响  

Effect of Glucose on the Performance of Li_(1.2)Ni_(0.13)Co_(0.13)Mn_(0.54)O_2 Synthesized by Sol-Gel Method

作　　者：王力臻[1,2] 徐勇[1] 方华[1] 高海丽[1] 

机构地区：[1]郑州轻工业学院,郑州450002 [2]河南省表界面重点实验室,郑州450002

出　　处：《无机化学学报》2015年第5期873-879,共7页Chinese Journal of Inorganic Chemistry

基　　金：国家自然科学基金面上项目(No.21471135);河南省基础与前沿技术研究重点项目(No.112300413216)资助

摘　　要：利用XRD、SEM、EDS、BET、激光粒度、循环伏安、恒流充放电、交流阻抗方法研究了葡萄糖为碳源对溶胶凝胶法制备Li1.2Ni0.13Co0.13Mn0.54O2正极材料的结构、形貌以及电化学性能的影响。结果表明:与前驱体中未加入葡萄糖所制备的材料相比,掺葡萄糖后样品颗粒分布相对均匀,粒径变小,D50从11.56减小至9.94μm,比表面积增加近1倍。经0.05C充放电活化后,未掺葡萄糖和掺葡萄糖样品0.2C放电比容量分别为183.4、211.6 m Ah·g-1,2C容量分别为其0.2C的62.2%、77.6%。1C循环50次后放电比容量分别为133.3、173.6 m Ah·g-1,容量保持率分别为95.1%、100%。掺葡萄糖可降低首次不可逆容量损失,提高材料的倍率性能与循环稳定性,减少电荷传递阻抗、Warburg阻抗以及双电层弥散效应,但不改变材料的晶型结构。The cathode material Li1.2Ni0.13Co0.13Mn0.54O2 was synthesized by sol-gel method modified by glucose as carbon source. The structure, morphology and electrochemical performances of the as-prepared sample was studied by methods of XRD, SEM, EDS, BET, Laser Particle Size Analysis, cyclic voltammetry, galvanostatic charge-discharge and AC impedance. Test results showed that the distribution of particles became uniform and the sizes became smaller for the modification by glucose. The D50 decreased from 11.56 to 9.94 μm. The specific surface area nearly doubled. The initial discharge specific capacity at 0.2C reached 183.4 m Ah·g^-1 and 211.6m Ah·g^-1after been activated by 0.05 C for blank and compared groups, respectively. The capacity at 2C retained62.2% and 77.6% of that at 0.2C for the two samples, respectively. After 50 cycles at 1C, the discharge specific capacities retained 133.3 m Ah·g^-1 and 173.6 m Ah·g^-1, and the capacity retention rates were 95.1% and 100% for the two samples, respectively. The initial irreversible capacity loss was reduced for the modification by glucose.The rate performance and cycle stability were obviously improved. The impedance of charge transfer and Warburg, and dispersion effect of the electric double layer were decreased. The crystal structure of the sample stayed unchanged.

关 键 词：锂离子电池 Li1.2Ni0.13Co0.13Mn0.54O2 溶胶凝胶法 葡萄糖 

分 类 号：TM911[电气工程—电力电子与电力传动]