Enhanced electrochemical performance of LiNi0.83Co0.12Mn0.05O2 cathodes with a fast-ion conductor Li0.33La0.56TiO3 coating layer

Ni-rich layered cathode materials LiNi x Co y Mn (1-x–y) O 2 (x ≥ 0.8) suffer from capacity decay due to structural deterioration during electrochemical cycling. To overcome these problems, the fast-ion conductor Li 0.33 La 0.56 TiO 3 (LLTO) is coated on the surface of LiNi 0.83 Co 0.12 Mn 0.05 O 2 (NCM83) cathodes through the sol–gel method, which can stabilize the electrode/electrolyte interface of cathode materials and facilitate Li + transport and charge transfer. As a result, the LLTO-coated NCM83 exhibits better cycle stability and higher rate performance. The NCM83 modified by 5 wt% LLTO has the discharge capacity of 185.9 mAh g −1 at 1C rate after 100 cycles and with higher capacity retention of 92.9% than the pristine NCM83 of 86.2%, and as well as the 5 wt% LLTO-coated NCM83 has a higher Li + -insert diffusion coefficient of 1.143 × 10 −11 cm 2  s −1 than the pristine NCM83 of 8.757 × 10 −12 cm 2  s −1 . Therefore, the fast-ion conductor LLTO coating strategy shows great potential in improving the performance of Ni-rich layered cathode materials.