Structural and Electrochemical Properties of Layered-Layered-Spinel Composite Cathode Materials LixMn4/6Ni1/6Co1/6O(1.75+0.5x) (1.1 < x < 1.3) for Lithium-Ion Batteries

摘要

The cathode materials LixMn4/6Ni1/6Co1/6O(1.75+0.5x) (x=l. 1, 1.2, 1.3) with different content of lithium have been synthesized by two step temperature co-precipitation in this paper. X-ray diffraction patterns confirm that there are spinel structure and layer structure in prepared composite. SEM images show that the same diameters of the assembled microspheres are at about 4 um in LixMn4/6Ni1/6Co1/6O(1.75+0.5x) composite. The measurement of electrochemical properties indicates that, with content of lithium varying from 1.1 to 1.3, content of spinel component declines, which induce to the increase of discharge capacity and decrease of capacity retention. Li1.1Mn4/6Ni1/6Co1/6O2.30 composite delivers best rate capability, because there is more spinel component in Li1.1Mn4/6Ni1/6Co1/6O2.30.