Preparation of Precursor of Lini0.5mn1.5o4 with High Density

The precursor of LiNi0.5Mn1.5O4 cathode material with high density was synthesized by two-dryness co-precipitation method. The optimized parameters were found out by studying the relationship between the density of precursor and the concentration of reactants, the manner of adding agglomerating agent, the remaining water in filter cake and the manner of dryness. The highest density (1.74 g/cm(3)) of precursor can be achieved under optimized condition: NiSO4 0.375 mol/L, coagulation agent added with little amount but many times, 28% of water in filter cake and two-step dryness, which is much better than that made by other methods. Our experiment provides a significant reference for the synthesis of excellent-performance cathode materials of lithium-ion battery. LiNi0.5Mn1.5O4 has a good cycle performance, a higher discharge capacity and a discharge platform of 4.7v, so it has become a research focus of 5-voltage cathode materials in the field of lithium ion battery recently.([1-4]) However, LiNi0.5Mn1.5O4 prepared by common methods usually has a lower tap volume capacity.([5-9]) HiroyuKi Ito([6]) reported a continuous fabricated high-density cobalt-manganese-doped nickel hydroxide method with which the density of product was between 1.5-1.91g/cm(3), however the used ammonia as a complexation agent in the preparation process not only increased the cost of the preparation, but also led to environmental pollution. Research results show that the cathode material synthesized using high-density precursor has a higher tap density, a larger volume capacity and a good electrochemical performance.([10]) In this paper, we find out the optimized parameters of preparation of precursor of LiNi0.5Mn1.5O4 by studying the relationship between the density of precursor and concentration of reactants, the manner of adding agglomerating agent, the remaining water in filter cake and the manner of dryness.