(中南大學 冶金科學與工程學院,長沙 410083)
摘 要: 采用快速共沉淀法制備Ni0.8Co0.1Mn0.1(OH)2前驅體,利用前驅體與LiOH·H2O的高溫固相反應得到鋰離子電池層狀正極材料LiNi0.8Co0.1Mn0.1O2,探討pH值對材料結構和電化學性能的影響。通過X射線衍射(XRD)、掃描電鏡(SEM)和電化學測試對合成樣品進行表征。結果表明,pH值為11.00~12.00時,合成的Ni0.8Co0.1Mn0.1(OH)2前驅體均無雜相;pH值為11.50時,合成的前驅體制備出的正極材料具有良好的電化學性能,0.1C倍率下首次放電比容量為192.4 mA·h/g;經過40次循環(huán),容量保持率為91.56%。
關鍵字: 鋰離子電池;正極材料;LiNi0.8Co0.1Mn0.1O2;共沉淀法;pH值
(School of Metallurgical Science and Engineering, Central South University, Changsha 410083, China)
Abstract:Ni0.8Co0.1Mn0.1(OH)2 precursors were synthesized by fast co-precipitation method and highly ordered layered LiNi0.8Co0.1Mn0.1O2 was prepared by heat-treatment of Ni0.8Co0.1Mn0.1(OH)2 precursors and LiOH·H2O. The effect of pH value on the structure and electrochemical properties of samples was studied. The prepared samples were characterized by X-ray powder diffractometry(XRD), scanning electron microscopy(SEM) and electrochemical tests. The results show that no impurities exist in the Ni0.8Co0.1Mn0.1(OH)2 synthesized at pH value ranging from 11.00 to 12.00. LiNi0.8Co0.1Mn0.1O2 prepared from Ni0.8Co0.1Mn0.1(OH)2 precursor synthesized under solution pH value of 11.50 shows excellent electrochemical performance. The initial discharge capacity is 192.4 mA·h/g at 0.1C, and the capacity remains 91.56% after 40 cycles.
Key words: lithium ion battery; cathode materials; LiNi0.8Co0.1Mn0.1O2; co-precipitation; pH value


