Hydrothermal synthesize of bi-functional interface structure modified LiMnPO4@LiFePO4/C nanorods as cathode materials for lithium-ion batteries

Olivine-structured LiMnPO 4 -based cathodes have generated enormous development prospects due to their high energy density , good structural stability , and low cost. However, their scale of application is limited by high electronic and ionic insulativity. In this study, we designed and synthesized a bi-functional interfacial modified composite, 0.9LiMnPO 4 @0.1LiFePO 4 /C ( [email protected] /C ), using mechanochemical activation-assisted hydrothermal technology. The innovative Li-storage structure consists of a high-energy density LiMnPO 4 (LMP) core, a uniformly coated LiFePO 4 (LFP) layer with improved ionic conductivity as the secondary outer shell, and an in-situ coated carbon film with high conductivity as the outermost functional skin. As anticipated, the [email protected] /C composite exhibits outstanding Li-storage properties, demonstrating discharge capacities as high as 157.1 mAh g −1 and 146.7 mAh g −1 at 0.1 C and 1 C rates, respectively. Moreover, it exhibits an ultrahigh capacity retention of 92.5 % after 500 charge and discharge cycles.