摘要
以Ni1-xCox(OH)2和LiOH.H2O为原料,采用软化学法在空气气氛中于700℃煅烧16h合成出层状LiNi1-xCoxO2正极材料,研究了不同掺钴量对材料的结构和电化学性能的影响,并用XRD及电性能测试考察了所得材料的结构与电化学性能。结果表明:低掺钴量(x≤0.1)时易生成无电化学活性的Li2Ni8O10化合物,高掺钴量(0.2≤x≤0.4)可促进LiNi1-xCoxO2层状结构的生成,有效减少阳离子混排及非化学计量产物的生成。电性能测试结果表明,掺钴量为0.3时的样品LiNi0.7Co0.3O2表现出最好的电化学性能,首次放电容量为172.5mAh/g,40次循环容量保持率达95%,显示较好的循环稳定性。
The layered LiCoxNi1-xO2 cathode materials for lithium ion batteries were prepared from Ni1-xCox （OH）2 and LiOH · H2O by a soft chemical Method in air atmosphere at 700℃ for 16h directly. The influence on the structure and electrochemical properties of the materials LiCoxNi1-xO2 （x=0,0. 1, 0. 2, 0.3, 0. 4） caused by different content of Co was investigated. XRD analysis and electrochemical tests were used to study the physical and the electrochemical performances of the materials. The results indicated that the products of Li2Ni8O10 is easy to be obtained with low content of Co （x≤0. 1）when synthesized at air atmosphere, while the high Co content （0. 2≤x≤0. 4） cathode materials have a much reduced degree of cation-mixing. The sample LiCo0. 3 Ni0. 7O2 has the best electrochemical properties. It has an initial charge capacity of 172. 5 mAh/g. After 40 cycles, this sample preserves 95% of the initial discharge capacity, showing perfect cyclic stability.
出处
《化工新型材料》
CAS
CSCD
北大核心
2006年第7期20-23,共4页
New Chemical Materials
基金
国家中小企业创新基金资助(04026215100776)
