Lithium‐Rich Nanoscale Li1.2Mn0.54Ni0.13Co0.13O2 Cathode Material Prepared by Co‐Precipitation Combined Freeze Drying (CP–FD) for Lithium‐Ion Batteries

Nanoscale Li-rich Li1.2Mn0.54Ni0.13Co0.13O2 material is synthesized by a co-precipitation combined freeze drying (CP–FD) method, and compared with a conventional co-precipitation method combined vacuum drying (CP–VD). With the combination of X-ray diffraction (XRD) and scanning electron microscopy (SEM), it is found that the sample from CP–FD method consists of a pure phase with good crystallinity and small, homogenous particles (100-300 nm) with uniform particle size distribution. Inductively coupled plasma spectroscopy (ICP) shows that the sample has a stoichiometric ratio of n(Li):n(Mn):n(Ni):n(Co)=9:4:1:1; and its Brunauer–Emmett–Teller (BET) specific surface area is 5.749 m2 g−1. This sample achieves excellent electrochemical properties: its initial discharge capacities are 298.9 mAh g−1 at 0.1C (20 mA g−1), 246.1 mAh g−1 at 0.5C, 215.8 mAh g−1 at 1C, and 154.2 mAh g−1 at 5C (5C charge and 5C discharge), as well as good cycling performance. In addition, the Li+ chemical diffusion coefficient of Li1.2Mn0.54Ni0.13Co0.13O2 material prepared by the CP–FD method is 4.59×10−11 cm2 s−1, which is higher than that of the Li1.2Mn0.54Ni0.13Co0.13O2 material prepared by CP–VD. This phenomenon illustrates the potential for Li1.2Mn0.54Ni0.13Co0.13O2 with good rate performance synthesized by CP–FD method.