Lithium-rich manganese-based oxides have the advantages of high discharge specific capacity, so they are potential candidates for advanced lithium battery cathode materials. However, they also have drawbacks to be sol...Lithium-rich manganese-based oxides have the advantages of high discharge specific capacity, so they are potential candidates for advanced lithium battery cathode materials. However, they also have drawbacks to be solved such as serious irreversible loss of capacity and voltage decay in the cycling process. Surface coating method was used in this paper to modify the lithium-rich manganese-based oxide(LRMO,Li_(1.2)Mn_(0.54)Ni_(0.13)Co_(0.13)O_(2)) to improve its electrochemical properties. Zirconium-based compounds coated LRMO materials(ZBC@LRMO) were obtained via the reaction of lithium hydroxide with zirconium n-butanol and subsequent thermal treatment at different temperatures. The results of X-ray diffraction and transmission electron microscopy confirm that the crystal structure and composition of the ZBC coating layer vary with the calcination temperature. The coating layer obtained at 600 ℃ is composed of tetragonal ZrO_(2) and Li_(2)ZrO_(3). The ZBC@LRMO sample with tetragonal ZrO =2 and Li_(2)ZrO_(3) composite exhibits the best electrochemical performance: the discharge capacity of ZBC@LRMO can reach 296 mAh g^(-1) at 0.1 C and 120 mAh g^(-1) at high rate of 5 C.展开更多
基金supported by the National Natural Science Foundation of China(No.21776051)the Research Fund Program of Key Laboratory of Fuel Cell Technology of Guangdong Province。
文摘Lithium-rich manganese-based oxides have the advantages of high discharge specific capacity, so they are potential candidates for advanced lithium battery cathode materials. However, they also have drawbacks to be solved such as serious irreversible loss of capacity and voltage decay in the cycling process. Surface coating method was used in this paper to modify the lithium-rich manganese-based oxide(LRMO,Li_(1.2)Mn_(0.54)Ni_(0.13)Co_(0.13)O_(2)) to improve its electrochemical properties. Zirconium-based compounds coated LRMO materials(ZBC@LRMO) were obtained via the reaction of lithium hydroxide with zirconium n-butanol and subsequent thermal treatment at different temperatures. The results of X-ray diffraction and transmission electron microscopy confirm that the crystal structure and composition of the ZBC coating layer vary with the calcination temperature. The coating layer obtained at 600 ℃ is composed of tetragonal ZrO_(2) and Li_(2)ZrO_(3). The ZBC@LRMO sample with tetragonal ZrO =2 and Li_(2)ZrO_(3) composite exhibits the best electrochemical performance: the discharge capacity of ZBC@LRMO can reach 296 mAh g^(-1) at 0.1 C and 120 mAh g^(-1) at high rate of 5 C.
