Advances in Sustain Stable Voltage of Cr-Doped Li-Rich Layered Cathodes for Lithium Ion Batteries

A series of Cr doped Li-rich cathodes has been synthesized using a carbonate-assisted coprecipitation method. Structural characterization based on X-ray diffraction (XRD) data and electron dispersive X-ray spectroscopy (EDX) mapping confirms the incorporation of Cr into crystal lattice. The doped cathode can initially deliver discharge a capacity of 219 mAh·g −1 with average voltage at 3.56 V and 170 mAh·g −1 with 3.36 V after 133 cycles at 0.2 C. Most importantly, the incorporation of Cr into the Li-rich cathodes is found to be capable of sustaining average voltage to a certain extent, which is believed to be associated with fewer amounts of spinel-domains generated upon deep cycling. The extents of electrochemical and structural evolution as a function of various doping levels are systematically investigated by battery cycling and high-resolution transmission electron microscope (HRTEM).