摘要
Surface deterioration occurs more easily in nickel-rich cathode materials with the increase of nickel content.To simultaneously pre-vent deterioration of active cathode materials and improve the electrochemical performance of the nickel-rich cathode material,the surface of nickel-rich LiNi_(0.6)Co_(0.2)Mn_(0.2)O_(2)cathode material is decorated with the stable structure and conductive Li_(3)PO_(4)by a facile method.The LiNi_(0.6)Co_(0.2)Mn_(0.2)O_(2)-1wt%,2wt%,3wt%Li_(3)PO_(4)samples deliver a high-capacity retention of more than 85%after 100 cycles at 1 C under a high voltage of 4.5 V.The effect of different coating amounts(0-5wt%)for the LiNi_(0.6)Co_(0.2)Mn_(0.2)O_(2)cathode is analyzed in detail.Results show that 2wt%coating of Li_(3)PO_(4)gives better performance compared to other coating concentrations.Detailed analysis of the structure of the samples during the charge−discharge process is performed by in-situ X-ray diffraction.It is indicated that the modification for LiNi_(0.6)Co_(0.2)Mn_(0.2)O_(2)cathode could protect the well-layered structure under high voltages.In consequence,the electrochemical performance of modified samples is greatly improved.
基金
This work was financially supported by the Guangdong Key Laboratory of Battery Safety(No.2019B121203008)
the National Natural Science Foundation of China(No.52072036),NSAF(No.U1930113)
the Beijing Natural Science Foundation(No.L182022)
the 13th Five-Year Plan of Advance Research and Sharing Techniques by Equipment Department(No.41421040202)
the China Postdoctoral Science Foundation(No.2021TQ0034).
