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LiFe_(1–x)CexPO_4/C cathode materials were synthesized by solid-state reaction method. The effects of various Ce-doping amounts on the microstructure and electrochemical performance of LiFePO_4/C cathode material were intensively investigated. The samples were characterized by X-ray diffraction(XRD), scanning electron microscope(SEM), galvanostatic charge-discharge measurements and electrochemical impedance spectroscopy(EIS). The results indicated that Ce-doping did not destroy the lattice structure of LiFePO_4/C, while enlarged the lattice volume tailored the particle size, decreased charge transfer resistance, increased electrical conductivity and Li-ion diffusion rate of LiFePO_4/C, and thus markedly enhanced the electrochemical performance of the LiFePO_4/C. Electrochemical test results showed that the LiFe_(0.9)Ce_(0.1)PO_4/C sample exhibited the best electrochemical performance with initial specific capacity of 155.4 m Ah/g at 0.2 C, the capacity retention ratios of 99.6% at 100 cycles at 1 C and delivered a discharge capacity of 160.1(0.1 C), 156.6(0.2 C), 151.2(0.5 C), 147.6(1 C), 140.7(2 C) and 136.7 m Ah/g(5 C), respectively, presented the best rate capacity among all the samples. EIS results demonstrated that the transfer resistance of the sample decreased greatly by doping an appropriate amount of Ce.
LiFe_ (1-x) CexPO_4 / C cathode materials were synthesized by solid-state reaction method. The effects of various Ce-doping amounts on the microstructure and electrochemical performance of LiFePO_4 / C cathode materials were intensively investigated. -ray diffraction (XRD), scanning electron microscope (SEM), galvanostatic charge-discharge measurements and electrochemical impedance spectroscopy (EIS). The results indicated that Ce-doping did not destroy the lattice structure of LiFePO 4 / C while in the enlarged the lattice volume tailored the particle size, decreased charge transfer resistance, increased electrical conductivity and Li-ion diffusion rate of LiFePO 4 / C, and thus markedly enhanced the electrochemical performance of the LiFePO 4 / C. Electrochemical test results showed that the LiFe_ (0.9) Ce 0.1 ) PO_4 / C sample exhibited the best electrochemical performance with initial specific capacity of 155.4 m Ah / g at 0.2 C, the capacity retention ratios of 99.6% at 10 0 cycles at 1 C and delivered a discharge capacity of 160.1 (0.1 C), 156.6 (0.2 C), 151.2 (0.5 C), 147.6 (1 C), 140.7 (2 C) and 136.7 m Ah / g , respectively, presented the best rate capacity among all the samples. EIS results of that the transfer resistance of the sample decreased greatly doping an appropriate amount of Ce.