Nano-sized LiFePO4/C composite with core-shell structure as cathode material for lithium ion battery

Nano-sized composite with LiFePO4-core and carbon-shell was synthesized via a facile route followed by heat treatment at 650 degrees C. X-ray diffraction (XRD) shows that the core is well crystallized LiFePO4. The electron microscopy (SEM and TEM) observations show that the core-shell structured LiFePO4/C composite coating with whole carbon shell layer of similar to 2.8 nm, possesses a specific surface area of 51 m(2) g(-1). As cathode material for lithium ion battery, the core-shell LiFePO4/C composite exhibits high initial capacity of 161 mAh g(-1) at 0.1 C, excellent high-rate discharge capacity of 135 mAh g(-1) at 5 C and perfect cycling retention of 99.6% at 100th cycle. All these promising results should be contributed to the core-shell nanostructure which prevents collapse of the particle structure in the long-term charge and discharge cycles, as well as the large surface area of the nano-sized LiFePO4/C composite which enhances the electronic conductivity and shortens the distance of lithium ion diffusion. (C) 2015 Elsevier Ltd. All rights reserved.