Journal of Inorganic Materials ›› 2018, Vol. 33 ›› Issue (3): 320-324.doi: 10.15541/jim20170192

• Orginal Article • Previous Articles     Next Articles

LiNixCoyMn1-x-yO2 Cathode Material Synthesized through Construction of E-pH Diagram and Its Electrochemical Performance

Ling LI1,2(), Yun-Jiao LI1,2(), Bin XU3, Wei-Sheng LU2, Qian-Ye SU1,2, Yong-Xiang CHEN1,2, Lin LI1   

  1. 1.School of Metallurgy and Environment, Central South University, Changsha 410083, China
    2. Citic Dameng Mining Industries Limited, Nanning 530028, China
    3. Qinghai Quick Donkey Hi Tech Co., Ltd., Xining 810000, China;
  • Received:2017-04-20 Revised:2017-09-06 Online:2018-03-20 Published:2018-03-12
  • About author:LI Ling. E-mail: 928012218@qq.com
  • Supported by:
    Glorious Laurel Scholar Program(2011A025);The major Science & Technology ([2017]11)

Abstract:

The thermodynamic data of various species in Li-Ni-Co-Mn-H2O system is obtained by thermodynamics calculation, and E-pH diagrams for Li-Ni-Co-Mn-H2O system with activity 1.00 at 25℃ and 200℃ were constructed. From E-pH diagrams, it shows that there is no predominant region of the LiNixCoyMn1-x-yO2 composite oxide in pH range of 3~13 at 25℃. However, the stability region of various species expands towards the low pH and low potential zones as the temperature increases. When pH is between 9.7~13.0 at 200℃, synthesis of LiNixCoyMn1-x-yO2 via aqueous process is thermodynamically possible, and high temperature is favorable. Experimental results showed that the composite precursor (LNCM) with α-NaFeO2 structure was successfully prepared in aqueous solution by using (Ni0.5Co0.2Mn0.3)(OH)2 as precursor and LiOH·H2O as raw material. LiNi0.5Co0.2Mn0.3O2 cathode materials were then obtained by post heat treatment and following tests exhibited excellent cycling performance. These experimental results are in consistent with the information given in E-pH diagram of the Li-Ni-Co-Mn-H2O system, and the as-prepared LiNi0.5Co0.2Mn0.3O2 cathode materials show excellent cycling performance.

Key words: E-pH diagram, Li-Ni-Co-Mn-H2O system, lithium ion battery, cathode material

CLC Number: 

  • TM912