Composite cathode active materials serve as remarkable lithium-ion reservoirs to achieve high energy density, high power, and cyclic durability in lithium-ion batteries (LIBs). In this study, the cycling stability of LIBs was investigated using composite cathodes fabricated by mixing LiCoO2 and LiMn0.6Fe0.4PO4 at different active material mass ratios. For composite cathodes with a LiCoO2 content > 40, the corresponding LIBs exhibited excellent cycle stability and high average working potential. In particular, for the composite cathode containing a balanced mass ratio of LiCoO2 and LiMn0.6Fe0.4PO4 (i.e., 40:40) the corresponding LIB achieved 81% specific energy retention (~ 200 Wh kg− 1), even after 500 charge–discharge cycles under high-current-density conditions (i.e., 8 C cycling). This was attributed to the modulation of the lithium-ion deintercalation/intercalation depth in LiCoO2 upon mixing with LiMn0.6Fe0.4PO4, thereby limiting the process to a shallower depth, and suppressing LiCoO2 degradation in the composite cathode. The combination of the high working potential of LiCoO2 and the ~ 4.1 V-class working potential derived from the manganese oxidation–reduction of LiMn0.6Fe0.4PO4 led to a sustained high cell voltage, contributing to a high specific energy in the corresponding LIB. Overall, these results reveal that a blend strategy is effective in the development of high-power LIBs with enhanced cycling stability. • Composite cathodes were prepared for lithium-ion batteries using LiCoO2 and LiMn0.6Fe0.4PO4• Batteries with LiCoO2-rich composite cathodes exhibited excellent cycling stability• An LiCoO2 content >40 provided composite cathodes with a high working potential• Balancing the LiCoO2-to-LiMn0.6Fe0.4PO4 mass ratio effectively alleviated LiCoO2 performance degradation• A remarkably high energy retention of 81% was exhibited in the battery based on a 40:40 LiCoO2/LiMn0.6Fe0.4PO4 cathode over 500 cycles at 8C
Abe et al. (Sat,) studied this question.