摘要
为改进传统固相法制备锂离子电池正极材料原料混合均匀性较低的缺点,将原料粉体磨细成粒度<1μm的超细粉体,以提高原料混合的均匀度,再进行焙烧合成,是一种新的制备方法。但超细粉体由于比表面积大,在制备、后处理和应用过程中极易发生团聚长大,影响后续制备过程和产品性能。添加适当的分散剂可以改善超细粉体分散稳定性能,防止团聚,同时有利于浆料磨制过程的进行。研究了柠檬酸铵、四甲基氢氧化铵、聚乙烯吡咯烷酮、一缩二乙二醇、三乙醇胺、马来酸-丙烯酸共聚物等6种不同分散剂对制备锂镍钴锰氧化物的原料在水中分散特性的影响。采用分散相的沉降实验、浆料流变行为和分散后颗粒的粒度分布实验等方法评价了分散效果。结果表明,在所研究的几种分散剂中,锂镍钴锰氧化物前驱物在水介质中最有效的分散剂是马来酸-丙烯酸共聚物。
Pulverizing the raw material powder into ultra-fine powder within less than 1 /~m particle size, and then calcining was a new method to prepare lithium-ion battery cathode materials, which overcomes the short coming of traditional solid-phase method that the mixing uniformity of raw materials was relatively low. Never theless, due to the large specific surface area, ultra-fine powders tend to agglomerate during the synthesis, pro- cessing and application, which could affect subsequent process and product performance. Appending the appro- priate dispersant can improve the stability of the suspension to lessen agglomerate, and shorten the grinding process of the aqueous suspension as well. In this article, dispersing abilities of six kinds of dispersants for raw material particles of Li Ni-Co-Mn ox ide suspension in aqueous media are discussed. These dispersants are ammonium citrate, tetramethylammonium hydroxide, polyvinylpyrrolidone, diethylene glycol, trolamine, and poly （acrylic acid-co-maleic acid）. Sediment experiments, rheology characterization and the size distribution of the dispersed particles in aqueous solution were employed to characterize the particle dispersion. Experimental results show that the most effective disper sant for raw material particles of Li-Ni-Co-Mn oxide in aqueous media was poly （acrylic acid-co-maleic acid）.
出处
《功能材料》
EI
CAS
CSCD
北大核心
2013年第B12期298-300,共3页
Journal of Functional Materials
基金
国家高技术研究发展计划(863计划)资助项目(2012AA052201)
关键词
超细粉体
分散剂
锂镍钴锰氧化物
团聚
ultrafine particles
dispersant
Li-Ni-Co-Mn oxide
agglomeration
