A series of treated samples prepared by using the as-prepared Li_1.3Ni_0.14Mn_0.68Co_0.07O₂ and sodium fluoride solution with various concentration. X-ray powder diffraction, scanning electron microscopy, infrared spectrum, Electrochemical impedance, cyclic voltammograms and charge-discharge tests were employed to investigate the structure and electrochemical performance of the treated samples. The results show that the treated optimal sample exhibits the best electrochemical performance among all samples while the molar ratio of Li_1.3Ni_0.14Mn_0.68Co_0.07O₂ to sodium fluoride is 1: 1.5. In the voltage range of 2.5 to 4.6V and 1C rate, the discharge capacity of the untreated and treated optimal sample exhibits the 1st cycle capacity of 71 and 128.6 mAh/g, respectively; and the 30th cycle capacity of 173.9 and 193.3 mAh/g. The charge-transfer resistance and polarization of the optimal sample significantly decreased, and the Ni-O，Co-O and Mn-O bond on the surface of the treated optimal sample enhanced, thereby the electrochemical performance of the sample improved.