Synthesizing LiNi_0.8Co_0.1Mn_0.1O₂ with novel shell-pore structure for enhanced rate performance

LiNi_0.8Co_0.1Mn_0.1O₂ with unique shell-pore structures is synthesized by a modified co-precipitation method. SEM images show that the synthesized materials are consisted of large particle (10–15 μm) with pores dispersed in the shell structure. Ex-situ SEM and ex-situ XRD analyses imply that the shell-pore may help to relieve the microstress generated during the long cycles, thus suppressing the formation of microcracks, alleviating the corrosion from electrolyte since less fresh interface exposed, and finally maintaining the layered structure. In addition, the shell-pore structure may also help improving the wettability of electrolyte and accelerating the Li ions transport. Accordingly, the samples with shell-pore structure own better cycle stability and rate performance. Specifically, they exhibit capacity retention of 90.33% after 100 cycles at 1C rate with the capacity of 169.7 mAh/g. It also improves the rate performance with the capacity of 157.3 mAh/g at 2C rate and 144.1 mAh/g at 5C rate respectively. Moreover, the modified co-precipitation method helps improving the compacted density of the as-prepared material.