Variations in the electrochemical properties of metallic elements-substituted LiNiO2 cathodes with preparation and cathode fabrication conditions

Variations in the electrochemical properties of LiNiO 2 with preparation and cathode fabrication conditions were studied. The LiNiO 2 cathode fabricated with a weight ratio of LiNiO 2 : acetylene black: binder = 85:10:5, after wet Spex milling for 60 min and drying in a shaking incubator showed the best cycling performance, with a discharge capacity degradation rate of 1.06 mAh/g/cycle between the first cycle and the 20 th cycle and a discharge capacity at n = 20 of 143.5 mAh/g at 0.1 C rate. LiNi 1− y M y O 2 cathodes with active material compositions of LiNiO 2 , LiNi 0.975 Ga 0.025 O 2 , LiNi 0.975 Al 0.025 O 2 , LiNi 0.995 Ti 0.005 O 2 , and LiNi 0.990 Al 0.005 Ti 0.005 O 2 were fabricated under these conditions. Among all the samples, LiNi 0.990 Al 0.005 Ti 0.005 O 2 had the highest first discharge capacities at 0.1 C rate (196.3 mAh/g) and 0.5 C rate (147.3 mAh/g). This sample had the smallest R-factor value, indicating that it had the lowest degree of cation mixing. At 0.1 C rate LiNiO 2 had the best cycling performance. At 0.5 C rate LiNi 0.975 Al 0.025 O 2 had the best cycling performance and its discharge capacity degradation rate was 1.28 mAh/g/cycle between the first cycle and the 20 th cycle.