熔融盐法合成高密度锂离子电池正极材料LiNi0.8Co0.2-xTixO2

Preparation of High Density LiNi_(0.8)Co_(0.2-x)Ti_xO_2 as Cathode Material for Lithium Ion Battery by a Molten Salt Method

利用具有低共熔组成的LiOH-LiNO3混合锂盐体系,与高密度前驱体掺杂Co的Ni(OH)2,TiO2粉末混合,经3阶段温度烧结制备出高密度Co-Ti共掺杂的锂离子电池正极材料LiNi0.8Co0.2-xTixO2(0≤x≤0.1)。XRD分析表明,合成的LiNi0.8Co0.2-xTixO2具有规整的层状α-NaFeO2结构。LiNi0.8Co0.2-xTixO2颗粒均匀,平均粒度为1～5μm,随掺Ti量的增加而减小,LiNi0.8Co0.15Ti0.05O2的振实密度达3.17g·cm-3。电性能测试表明,在0.2C放电倍率和3.0～4.3V的电压范围内,LiNi0.8Co0.15Ti0.05O2首次放电比容量达169mAh·g-1,且具有良好的循环性能和高倍率放电性能。

Co-Ti co-doped cathode material LiNi(0.8)Co(0.2-x)TixO(2) (0 <= x <= 0.1) with a high tamping-density for Li ion battery was prepared by a molten-salt synthesis method using eutectic molten salt 0.62LiNO(3)-0.38LiOH, high-density precursor Co-doped Ni(OH)(2) and TiO2 powder. X-ray diffraction analysis shows that the synthesized material has a well-developed layered alpha-NaFeO2 structure. LiNi0.8Co0.2-xTiO2 has homogeneous particles with average sizes of 1-5 mu m and the particles become smaller with Ti content increasing. The tamping-density of LiNi0.8Co0.15Ti0.05O2 reaches to 3.17 g.cm(-3). Charge-discharge tests show that LiNi0.8Co0.15Ti0.05O2 has an initial discharge capacity as high as 169 mAh.g(-1) and excellent capacity retention in the range 3.0-4.3 Vat a specific current of 0.2 C.