Synthesis and electrochemical performance evaluations of polyhedra spinel LiAlxMn2-xO4 (x≤0.20) cathode materials prepared by a solution combustion technique

JOURNAL OF ALLOYS AND COMPOUNDS

卷:728

Article

Liu, Jintao^1,2,3  Li, Gang^1,2,3  Yu, Yue^1,2,3  Bai, Hongli^1,2,3  Shao, Miaomiao^1,2,3  Guo, Junming^1,2,3  Su, Changwei^1,2,3  Liu, Xiaofang^1,2,3  Bai, Wei^1,2,3 

[1] Yunnan Minzu Univ, Key Lab Comprehens Utilizat Mineral Resources Eth, Kunming 650500, Yunnan, Peoples R China

[2] Yunnan Minzu Univ, Educ Dept Yunnan, Key Lab Resource Clean Convers Ethn Reg, Kunming 650500, Yunnan, Peoples R China

[3] Yunnan Minzu Univ, Joint Res Ctr Int Cross Border Ethn Reg Biomass C, Kunming 650500, Yunnan, Peoples R China

关键词: Lithium-ion batteries;    Solution combustion technique;    Al-doping;    Spinel LiMn2O4;    Cathode material;    Polyhedra;   

DOI  :  10.1016/j.jallcom.2017.09.098

来源: Elsevier

【 摘 要 】

A series of single-crystal polyhedra spinel LiAlxMn2-xO4 (x = 0, 0.05, 0.10, 0.15 and 0.20) cathode materials have been rapidly prepared by a solution combustion technique using HNO3 solution as an auxiliary oxidant. The crystal structure and phase identification of as-prepared samples were characterized through X-ray diffraction (XRD), which shows that all samples present the characteristic diffraction peaks of spinel LiMn2O4. The morphology and particle size of as-prepared samples were observed by field emission scanning electron microscope (FESEM) and transmission electron microscope (TEM), which indicate that all samples have single-crystal polyhedra morphology and good crystallinity. The cycling performances of as-prepared samples were evaluated by galvanostatic charge/discharge cycling performance tests, which demonstrate that LiAl0.10Mn1.90O4 exhibits the optimal cycling and rate properties. It delivers a capacity retention rate of 60.7% after 2000 cycles with an initial discharge specific capacity of 99.5 mAh g(-1) at 10 C (1 C = 148 mAh g(-1)) and 25 degrees C, while the capacity retention rate of pristine LiMn2O4 is only 9.6% with an initial discharge specific capacity of 81 mAh g(-1) at the same conditions. The Al-doped samples show better elevated temperature cycling stability than pristine LiMn2O4. LiAl0.10Mn1.90O4 sample shows a capacity retention rate of 81.5% with a discharge specific capacity of 91.3 mAh g(-1) after 500 cycles at 1 C and 55 degrees C, which is much superior compared with the capacity retention rate of 18.5% for pristine LiMn2O4. Cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS) tests certify that LiAl0.10Mn1.90O4 presents the better electrode reversibility, more rapidly charge-transfer and Li+ diffusion kinetics processes. (C) 2017 The Authors. Published by Elsevier B.V.

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