Effect of precipitators on the morphologies and electrochemical properties of Li_1.2Mn_0.54Ni_0.13Co_0.13O₂ via rapid nucleation and post-solvothermal method

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• 作者：Wenchao Yan^a ; ^b ; Jicheng Jiang^a ; ^b ; Wei Liu^a ; Deye Sun^a ; Erqing Zhao^a ; Yongcheng Jin^a ; ^{jinyc@qibebt.ac.cn} ; Kiyoshi Kanamura^c ; ^{kanamura@tmu.ac.jp}
• 关键词：Rapid nucleation ; Precipitator ; Solvothermal method ; Spherical particles ; Li-ion batteries
• 刊名：Electrochimica Acta
• 出版年：2017
• 出版时间：10 January 2017
• 年：2017
• 卷：224
• 期：Complete
• 页码：161-170
• 全文大小：3595 K
• 卷排序：224

文摘

Different morphologies of Li-rich layered oxides, Li1.2Mn0.54Co0.13Ni0.13O2 (LMNCO), were synthesised using a rapid nucleation and post-solvothermal method followed by calcination. After the process of rapid nucleation, the as-prepared mixture of M(OH)2 using NaOH as the precipitator showed nanoplate aggregation, while the mixture of MCO3 using (NH4)2CO3 as the precipitator presented a spherical morphology. After subsequent solvothermal processing and calcination, Li1.2Mn0.54Co0.13Ni0.13O2 samples with uniform nanoplate particles (LMNCO-P) and spherical particles (LMNCO-S) were obtained. The as-prepared LMNCO-P and LMNCO-S samples exhibited excellent electrochemical performance and delivered high initial discharge capacities of 282 and 278 mA h g−1, respectively, at 0.1C with a cut-off voltage in the range 2.0–4.8 V. The LMNCO-S cathode material exhibited outstanding cycling performance with capacity retention ratios of 88%, 89%, and 92% at 1, 2, and 5C, respectively, after 100 cycles. Furthermore, after a stepped pre-cycling treatment, the capacity retention of the LMNCO-S cathode material reached 79% after 500 cycles at 5C. The superior cycling performance can be ascribed to the spherical morphology with a small surface area, which decreased side reactions with the electrolyte and enhanced the crystal structure stability after the pre-cycling treatment.