Acta Chimica Sinica ›› 2021, Vol. 79 ›› Issue (5): 678-684.DOI: 10.6023/A21010019 Previous Articles    



李童心1, 李东林1,*(), 张清波1, 高建行1, 孔祥泽1, 樊小勇1, 苟蕾1   

  1. 1 长安大学 材料科学与工程学院 能源材料与器件研究所 西安 710061
  • 投稿日期:2021-01-21 发布日期:2021-03-31
  • 通讯作者: 李东林
  • 基金资助:

Preparation and Electrochemical Performance of Macroporous Ni-rich LiNi0.8Co0.1Mn0.1O2 Cathode Material

Tongxin Li1, Donglin Li1,*(), Qingbo Zhang1, Jianhang Gao1, Xiangze Kong1, Xiaoyong Fan1, Lei Gou1   

  1. 1 Institute of Energy Materials and Device, School of Materials Science and Engineering, Chang’an University, Xi’an 710061, China
  • Received:2021-01-21 Published:2021-03-31
  • Contact: Donglin Li
  • About author:
    *E-mail: Tel.: 029-82337340
  • Supported by:
    National Natural Science Foundation of China(21473014)

High-performance rechargeable lithium-ion batteries (LIBs) have been widely applied in electrochemical energy storage fields. In recent years, Ni-rich ternary cathode materials have received considerable attention due to their low cost and high theoretical specific capacity, and they are regarded as promising candidates for the next-generation lithium-ion batteries. In this paper, macroporous Ni-rich LiNi0.8Co0.1Mn0.1O2(NCM811) cathode material has been successfully prepared by using a poly(methyl methacrylate) (PMMA) colloidal crystal template and sol-gel method. The typical experimental procedure for the synthesis of macroporous LiNi0.8Co0.1Mn0.1O2 is as follows: Firstly, a stoichiometric mixture of LiNO3, (CH3COO)2Mn∙4H2O, (CH3COO)2Co∙4H2O, and (CH3COO)2Ni∙4H2O were dissolved together in ethanol for 1 h. Acetylacetone was then drop by drop into the prepared solution under continuous stirring for 1.5 h (a molar ratio of acetylacetone to transition metal ions was 1∶1). Then, the LiNi0.8Co0.1Mn0.1O2sol was infiltrated completely into PMMA template under vacuum. After that, the as-prepared product was filtrated and dried at 50 ℃, followed by a heat treatment at 450 ℃ for 2 h for removing the PMMA template, and then calcined at 700 ℃ under a flowing oxygen atmosphere. These results suggest that the macroporous architecture stacked by the 100 nm particles is obtained by using the pore-forming agent PMMA, and this structure is beneficial to improve the rate capability and cycling stability of the Ni-rich cathode materials. Specifically, macroporous NCM811 delivers an initial discharge capacity of 190.3 mAh∙g-1 between 2.7 V and 4.3 V at 0.1C rate. The discharge specific capacity of the nanoparticle NCM811 is only 129.3 mAh∙g-1 at 2C rate, whereas the macroporous NCM811 is 149.8 mAh∙g-1 at the same rate. In addition, macroporous NCM811 can still delivers a high discharge specific capacity of 111.7 mAh∙g-1 at 10C rate. Macroporous NCM811 also exhibits superior capacity retention of 83.02% after 400 cycles at 0.5C rate, surpassing the 38.59% of nanoparticle NCM811 obviously. The macroporous architecture is conducive to shorten the transport distance of lithium ions and electrons, suppress the phase transition and structural deterioration resulting from the frequent Li+ insertion/deinsertion, reduce polarization, and thus improving the electrochemical performances, which provides new insights for the development of high-energy-density lithium-ion batteries.

Key words: lithium-ion batteries, cathode material, colloidal crystal template, macroporous, LiNi0.8Co0.1Mn0.1O2