High-rate capability of spinel LiNi0.05Mn1.95O4 cathode for
Li-ion batteries prepared via coprecipitated precursor
Li-ion batteries prepared via coprecipitated precursor
(1. College of Materials Science and Engineering, South China University of Technology, Guangzhou 510640, China;
2. Guangzhou Hongsen Material Co. Ltd., Guangzhou 510760, China)
2. Guangzhou Hongsen Material Co. Ltd., Guangzhou 510760, China)
Abstract: Spinel LiNi0.05Mn1.95O4 cathode material for lithium ion batteries was synthesized by solid-state reaction from coprecipitated Ni-Mn hydroxide precursors and characterized by X-ray diffraction(XRD), scanning electron microscopy(SEM) and galvanostatic charge-discharge tests. It is found that LiNi0.05Mn1.95O4 powder has an ordered cubic spinel phase (space group and exhibits superior rate capability. After 450 cycles, the LiNi0.05Mn1.95O4/carbonaceous mesophase spheres(CMS) Li-ion batteries can retain 96.0% and 93.3% capacity at 5C and 10C charge/discharge rate, respectively, compared with 85.3% (5C) and 80.5% (10C) retention for LiMn2O4 batteries. However, the initial discharge capacity of LiNi0.05Mn1.95O4/CMS batteries at 1C charge/discharge rate (96.20 mA∙h/g) is slightly lower than that of the LiMn2O4 batteries (100.98 mA∙h/g) due to the increased average oxidation state of Mn in LiNi0.05Mn1.95O4.
Key words: Li-ion battery; rate capability; Ni-doped Mn spinel; coprecipitation