Li ₂ MnO ₃ stabilized LiNi _1/3 Co _1/3 Mn _1/3 O ₂ cathode with improved performance for lithium ion batteries

Li ₂ MnO ₃ stabilized LiNi _1/3 Co _1/3 Mn _1/3 O ₂ cathode materials are discussed by xLi ₂ MnO ₃ ·(1 - x)LiNi _1/3 Co _1/3 Mn _1/3 O ₂ (x = 0.3 and 0.7) solid solutions. The solid solutions were synthesized by annealing the mixing LiNO ₃ , Mn(NO ₃ ) ₂ and LiNi _1/3 Co _1/3 Mn _1/3 O ₂ powder at 900 C for 12 h, and it was found that the cathode particle size increased from 200-300 to 300-500 nm. The pristine LiNi _1/3 Co _1/3 Mn _1/3 O ₂ showed the 30th discharge capacity of 174.5 mAh g ^-1 . Our results indicated that the introduction of Li ₂ MnO ₃ in the cathode could increase performance. 0.3Li ₂ MnO ₃ ·0.7LiNi _1/3 Co _1/3 Mn _1/3 O ₂ cathode shows higher discharge of 182.0 mAh g ^-1 in the 30th cycle. And the discharge capacity of 214.1 mAh g ^-1 was obtained when the Li ₂ MnO ₃ content increased to 0.7. Moreover, the cyclic performance at 55 C was also increased by Li ₂ MnO ₃ . For instance, the discharge capacities were 191.2 mAh g ^-1 (x = 0.3) and 229.3 mAh g ^-1 (x = 0.7) and the capacity retentions are 94.9% and 91.4% after 40 cycles, respectively. The DFT calculations show that stable Li ₂ MnO ₃ -enriched layer is as a result of enhanced performance.