Nb-doping in LiNi0.8Co0.1Mn0.1O2 cathode material: Effect on the cycling stability and voltage decay at high rates

Layered structure nickel-rich LiNi0.8Co0.1Mn0.1O2 possesses the superiority of high discharge capacity and voltage platform. However, the cycling instability and seriously voltage decay limited its cosmically commercial. Herein, Nb-doped Li(Ni0.8Co0.1Mn0.1)O-2 cathode materials are synthesized by urea hydrothermal method assisted high temperature solid state process aimed at improving the cycle stability and inhibiting the voltage decay. The analysis results show that the Nb-doped samples reveal a silkworm shape with loosely aggregated surface, stable structure and enlarged diffusion coefficient of Li-ion. The electrochemical data indicates that Nb-doping not only enhance the rate and cycle performance at a high cut-off voltage of 4.6 V, but also inhibit the voltage decay at high rates. Between 2.8V and 4.6 V, after 100 cycles, the capacity retention of 1% Nb-doped sample is 10.7% and 17% higher than that of the pristine sample at 1 C and 5 C, respectively. (C) 2019 Taiwan Institute of Chemical Engineers. Published by Elsevier B.V. All rights reserved.