| 초록 |
To investigate the synergistic effect of different types of conductive additives on the cathode performance of lithium-ion batteries, various types of cathode materials (LiCoO2, LiFePO4, LiNi0.6Co0.2Mn0.2O2) containing different ratios of vapor-grown carbon fibers (VGCFs) and carbon black (Super-P) are investigated. Pillar-like morphology of the VGCF enabled them to efficiently connect to the active materials and hence, these achieve the highest electrical conductivity for LiCoO2and LiFePO4 (both of which are composed of primary particles). On the other hand, for LiNi0.6Co0.2Mn0.2O2, composed of micro-sized secondary particles embedded with nano-sized primary particles, a mixture of VGCF and Super-P shows synergistically improved electrical conductivity. Well-dispersed Super-P helps electron transfer over constituent primary particles. The cathode with higher electrical conductivity shows improved results for both cycle performance and rate capability. |
