Improved electrochemical performance of bagasse and starch-modified LiNi0.5Mn0.3Co0.2O2 materials for lithium-ion batteries

Organic carbon-coated LiNi 0.5 Mn 0.3 Co 0.2 O 2 materials are prepared by mixing 2 or 5% starch or bagasse evenly with the synthesized LiNi 0.5 Mn 0.3 Co 0.2 O 2 material and calcining for 10 h at 750 °C. The microstructures and electrochemical performance are investigated by X-ray diffraction, scanning electron microscopy, carbon/sulfur analysis, transmission electron microscopy and electrochemical testing. The results indicate that the organic carbon coated on the surface of LiNi 0.5 Mn 0.3 Co 0.2 O 2 material does not change the surface morphology and crystal structure, but greatly improves the conductivity, rate and cycle performance of the LiNi 0.5 Mn 0.3 Co 0.2 O 2 cathode in a Li-ion battery. The initial discharge capacity of the synthesized LiNi 0.5 Mn 0.3 Co 0.2 O 2 material is 147.8 mAh g −1 , which increases to 152.4 and 153.3 mAh g −1 for 2% starch and bagasse, respectively. After 100 cycles, the capacity retention rates are 70.7% (uncoated), 83.3% (coated with 2% starch), 90.1% (coated with 2% bagasse), 83.1% (coated with 5% starch) and 91.1% (coated with 5% bagasse). The influence of the percentage of coated carbon and its dispersion uniformity on the performance of the battery is analyzed. A small coating capacity and uniform carbon film can achieve better performance. Rational organic carbon coating technology is an effective way to improve the electrochemical performance of LiNi 1− x − y Mn x Co y O 2 -based material.