共沉淀法合成(Ni1/3Co1/3Mn1/3)(OH)2热力学分析

通过对共沉淀Me2+ (Me = Ni, Co, Mn)－NH3－OH-－H2O体系进行热力学分析，拟合出lgMe]－pH关系曲线。以氢氧化钠为共沉淀剂，氨水为络合剂，采用共沉淀法进行锂离子电池(LIB)正极材料LiNi1/3Co1/3Mn1/3O2前驱体(Ni1/3Co1/3Mn1/3)(OH)2的合成研究。热力学分析结果表明：共沉淀体系的最佳pH值为11，合适的氨水浓度N]为0.1～0.5 mol/L，此时各种金属阳离子(Me2+)的损失最小。基于以上最佳合成反应条件，在不加其它还原剂和絮凝剂时，所得前驱体材料的振实密度达到1.32 g/cm3。

Thermodynamic analysis of the synthesis of precursor (Ni1/3Co1/3Mn1/3)(OH)2 by a co-precipitation method

Thermodynamic analysis of the Me2+ (Me = Ni, Co, Mn)－NH3－OH-－H2O co-precipitation system was carried out at first, and then the relationship between lgMe] and pH value was simulated. Based on this, the precursors (Ni1/3Co1/3Mn1/3)(OH)2 for cathode material LiNi1/3Co1/3Mn1/3O2 were synthesized by a co-precipitation method using sodium hydroxide (NaOH) as a precipitation agent and ammonia (NH3•H2O) as a complexing agent. The results of thermodynamic analysis for this co-precipitation system showed that the optimum pH value and ammonia concentration range for the precursor synthesis were 11 and 0.1～0.5 mol/L, respectively. Meanwhile, the least metal cation (Me2+) loss was obtained. Under the optimum reaction condition mentioned above with neither other reducing agent nor flocculation agent, the tap density of the precursor powder synthesized reaches 1.32 g/cm3.