摘要
采用共沉淀法合成Ni_(0.6)Co_(0.2)Mn_(0.2)(OH)_(2)前驱体,利用Photoshop软件和Matlab软件对前驱体颗粒的扫描电子显微镜法(SEM)图像进行了处理和分形维数值的计算,探究了分形维数值与球形度的对应关系,选择分形维数较高的前驱体高温烧结制备出正极材料并进行高倍率下的电化学性能检测,结果表明256 dpi×256 dpi的SEM图像分辨率条件下,前驱体颗粒的分形维数值在0.975~0.995,分形维数值与反应体系pH值之间存在线性对应关系。在3 C电流密度下,截止电压为4.3、4.4和4.5 V时,首次放电比容量为160.3、173.7和179.7 mAh/g,首次效率为72.93%、83.08%和74.19%,循环250次后,容量保持率为74.55%、77.03%和76.46%。
The precursor Ni_(0.6)Co_(0.2)Mn_(0.2)(OH)_(2) precursor was synthesized by coprecipitation method.Photoshop and Matlab software was used to process the SEM image of the precursor particles and calculate the fractal dimension value.The corresponding relationship between the fractal dimension value and the sphericity was explored.The precursor with higher fractal dimension was selected and sintered at high temperature to prepare cathode material,and the electrochemical performance was tested at high rate.The results show that the fractal dimension of the precursor particles ranges from 0.975 to 0.995 under the SEM image resolution of 256 dpi×256 dpi,and there is a linear relationship between the fractal dimension value and the pH value of the reaction system.At the current density of 3 C,the initial discharge specific capacity is 160.3,173.7 and 179.7 mAh/g at the cut-off voltage of 4.3,4.4 and 4.5 V,and the initial efficiency is 72.93%,83.08%and 74.19%.After 250 cycles,the capacity retention is 74.55%,77.03%and 76.46%.
作者
吴浩
郑江峰
张晨
高琦
罗敏
WU Hao;ZHENG Jiangfeng;ZHANG Chen;GAO Qi;LUO Min(R&D Center of Guangdong Jiana Energy Technology Co.,Ltd.,Qingyuan Guangdong 513056,China)
出处
《电源技术》
CAS
北大核心
2021年第4期440-442,527,共4页
Chinese Journal of Power Sources
基金
清远市科技计划项目(2019年清科函[2019]126号300)
广东省重点实验室专项(2020年粤财科教[2020]53号)。
关键词
共沉淀法
分形维数
正极材料
高倍率循环
coprecipitation method
fractal dimension
cathode material
high rate cycling
