LiCo1/3Ni1/3Mn1/3O2 was coated by a layer of 1.0 wt% CeO2 via sol-gel method. The bared and coated LiMn1/3Co1/3Ni1/3O2 was characterized by X-ray diffraction (XRD),scanning electron microscopy (SEM),cyclic voltammogra...LiCo1/3Ni1/3Mn1/3O2 was coated by a layer of 1.0 wt% CeO2 via sol-gel method. The bared and coated LiMn1/3Co1/3Ni1/3O2 was characterized by X-ray diffraction (XRD),scanning electron microscopy (SEM),cyclic voltammogram (CV) and galvanotactic charge-discharge test. The results show that the coating layer has no effect on the crystal structure,only coating on the surface; the 1.0 wt% CeO2-coated LiCo1/3Ni1/3Mn1/3O2 exhibits better discharge capacity and cycling performance than the bared LiCo1/3Ni1/3Mn1/3O2. The discharge capacity of 1.0 wt% CeO2-coated cathode is 182.5 mAh.g-1 at a current density of 20 mA.g-1,in contrast to 165.8 mAh.g-1of the bared sample. The discharge capacity retention of 1.0 wt% CeO2-coated sample after 12 cycles reaches 93.2%,in comparison with 86.6% of the bared sample. CV results show that the CeO2 coating could suppress phase transitions and prevent the surface of cathode material from direct contact with the electrolyte,thus enhance the electro-chemical performance of the coated material.展开更多
镍钴锰酸锂Li(Ni_(1/3)Co_(1/3)Mn_(1/3))O_2与磷酸铁锂按照一定的质量比球磨混合制得复合材料,电化学测试结果表明,电池的循环性能随着Li(Ni_(1/3)Co_(1/3)Mn_(1/3))O_2的增加而不断提升,当Li(Ni_(1/3)Co_(1/3)Mn_(1/3))O_2与LiFePO_4...镍钴锰酸锂Li(Ni_(1/3)Co_(1/3)Mn_(1/3))O_2与磷酸铁锂按照一定的质量比球磨混合制得复合材料,电化学测试结果表明,电池的循环性能随着Li(Ni_(1/3)Co_(1/3)Mn_(1/3))O_2的增加而不断提升,当Li(Ni_(1/3)Co_(1/3)Mn_(1/3))O_2与LiFePO_4的质量比为7∶3时性能达到最佳,初始放电比容量为150.7 m Ah/g,循环60次后的放电比容量为147.6 m Ah/g,容量保持率高达97.96%;同时复合材料的平均工作电压为3.72 V(vs.Li+/Li),显著高于LiFePO_4的3.40 V(vs.Li+/Li)的放电电压平台,表现出更好的循环性能和更高的比容量。展开更多
Layered cathode material LiCo1/3Ni1/3Mn1/3O2 was synthesized by Pechini process, and investigated using X-ray diffraction (XRD), scanning electron microscopy (SEM) and galvanostatic charge/discharge cycling. The sampl...Layered cathode material LiCo1/3Ni1/3Mn1/3O2 was synthesized by Pechini process, and investigated using X-ray diffraction (XRD), scanning electron microscopy (SEM) and galvanostatic charge/discharge cycling. The sample is well-crystallized and has a phase-pure a-NaFeO2 structure. The particle sizes are uniform, and distributed in the range of 20-200 nm. The initial discharge capacity of the Li/LiCo1/3Ni1/3Mn1/3O2 cell was about 149 mAh·g-1 when it was cycled at a voltage range of 4.5-2.3 V with a specific current of 0.25 mA. The result is better in comparison with solid-state solution method. The synthetic procedure was discussed. Three major reactions: chelation, esterification, and polymerization successively occurred.展开更多
文摘LiCo1/3Ni1/3Mn1/3O2 was coated by a layer of 1.0 wt% CeO2 via sol-gel method. The bared and coated LiMn1/3Co1/3Ni1/3O2 was characterized by X-ray diffraction (XRD),scanning electron microscopy (SEM),cyclic voltammogram (CV) and galvanotactic charge-discharge test. The results show that the coating layer has no effect on the crystal structure,only coating on the surface; the 1.0 wt% CeO2-coated LiCo1/3Ni1/3Mn1/3O2 exhibits better discharge capacity and cycling performance than the bared LiCo1/3Ni1/3Mn1/3O2. The discharge capacity of 1.0 wt% CeO2-coated cathode is 182.5 mAh.g-1 at a current density of 20 mA.g-1,in contrast to 165.8 mAh.g-1of the bared sample. The discharge capacity retention of 1.0 wt% CeO2-coated sample after 12 cycles reaches 93.2%,in comparison with 86.6% of the bared sample. CV results show that the CeO2 coating could suppress phase transitions and prevent the surface of cathode material from direct contact with the electrolyte,thus enhance the electro-chemical performance of the coated material.
文摘镍钴锰酸锂Li(Ni_(1/3)Co_(1/3)Mn_(1/3))O_2与磷酸铁锂按照一定的质量比球磨混合制得复合材料,电化学测试结果表明,电池的循环性能随着Li(Ni_(1/3)Co_(1/3)Mn_(1/3))O_2的增加而不断提升,当Li(Ni_(1/3)Co_(1/3)Mn_(1/3))O_2与LiFePO_4的质量比为7∶3时性能达到最佳,初始放电比容量为150.7 m Ah/g,循环60次后的放电比容量为147.6 m Ah/g,容量保持率高达97.96%;同时复合材料的平均工作电压为3.72 V(vs.Li+/Li),显著高于LiFePO_4的3.40 V(vs.Li+/Li)的放电电压平台,表现出更好的循环性能和更高的比容量。
文摘Layered cathode material LiCo1/3Ni1/3Mn1/3O2 was synthesized by Pechini process, and investigated using X-ray diffraction (XRD), scanning electron microscopy (SEM) and galvanostatic charge/discharge cycling. The sample is well-crystallized and has a phase-pure a-NaFeO2 structure. The particle sizes are uniform, and distributed in the range of 20-200 nm. The initial discharge capacity of the Li/LiCo1/3Ni1/3Mn1/3O2 cell was about 149 mAh·g-1 when it was cycled at a voltage range of 4.5-2.3 V with a specific current of 0.25 mA. The result is better in comparison with solid-state solution method. The synthetic procedure was discussed. Three major reactions: chelation, esterification, and polymerization successively occurred.
