Effects of synthesis conditions on layered Li[Ni1/3Co1/3Mn1/3]O2 positive-electrode via hydroxide co-precipitation method for
lithium-ion batteries
lithium-ion batteries
(1. State Key Laboratory of Powder Metallurgy, Central South University, Changsha 410083, China;
2. Department of Chemistry and Materials Science, Hunan Institute of Humanities, Science and Technology,
Loudi 417000, China)
2. Department of Chemistry and Materials Science, Hunan Institute of Humanities, Science and Technology,
Loudi 417000, China)
Abstract: Layered Li[Ni1/3Co1/3Mn1/3]O2 was synthesized with complex metal hydroxide precursors that were prepared by a co-precipitation method. The influence of coordination between ammonia and transition-metal cations on the structural and electrochemical properties of the Li[Ni1/3Co1/3Mn1/3]O2 materials was studied. It is found that when the molar ratio of ammonia to total transition-metal cations is 2.7:1, uniform particle size distribution of the complex metal hydroxide is observed via scanning electron microscopy. The average particle size of Li[Ni1/3Co1/3Mn1/3]O2 materials was measured to be about 500 nm, and the tap-density was measured to be approximately 2.37 g/cm3, which is comparable with that of commercialized LiCoO2. XRD analysis indicates that the presently synthesized Li[Ni1/3Co1/3Mn1/3]O2 has a hexagonal layered-structure. The initial discharge capacity of the Li[Ni1/3Co1/3Mn1/3]O2 positive-electrode material is determined to be 181.5 mA∙h/g using a Li/Li[Ni1/3Co1/3Mn1/3]O2 cell operated at 0.1C in the voltage range of 2.8−4.5 V. The discharge capacity at the 50th cycle at 0.5C is 170.6 mA∙h/g.
Key words: layered structure; coordination effect; hydroxide co-precipitation; cathode material; lithium ion batteries