采用高温固相法烧结制备得到正极材料Li Ni0.5Co0.2Mn0.3O2,通过X射线衍射(XRD)、扫描电镜(SEM)以及循环伏安(CV)、交流阻抗(EIS)等电化学性能测试手段,探讨高温烧结工艺中不同锂源对材料结构、形貌及电化学性能的影响,结果表明,采用Li...采用高温固相法烧结制备得到正极材料Li Ni0.5Co0.2Mn0.3O2,通过X射线衍射(XRD)、扫描电镜(SEM)以及循环伏安(CV)、交流阻抗(EIS)等电化学性能测试手段,探讨高温烧结工艺中不同锂源对材料结构、形貌及电化学性能的影响,结果表明,采用Li OH作为锂源合成的材料与采用其他锂源相比,具有较好的层状结构和电化学性能.该材料在0.1C倍率下的首次充放电容量和库伦效率较高(172.7 m Ah/g,89.08%),在0.5C、1C倍率下循环50次后,材料的放电容量仍保持在144.5 m Ah/g和136.2 m Ah/g.展开更多
采用化学共沉淀法预先合成球形前驱体Ni0.5Co0.2Mn0.3（OH）2,再与锂源共混后高温煅烧合成高容量正极材料Li Ni0.5Co0.3Mn0.2O2。探讨了不同烧结制度对材料结构性能的影响。X射线衍射（XRD）结果表明,产物结构为α-Na Fe O2型层状结构...采用化学共沉淀法预先合成球形前驱体Ni0.5Co0.2Mn0.3（OH）2,再与锂源共混后高温煅烧合成高容量正极材料Li Ni0.5Co0.3Mn0.2O2。探讨了不同烧结制度对材料结构性能的影响。X射线衍射（XRD）结果表明,产物结构为α-Na Fe O2型层状结构。扫描电子显微镜（SEM）显示材料具有良好的球形形貌。测试材料的电化学性能,在2.75~4.20 V和2.75~4.35 V充放电截止电压,0.5 C充放电电流下,首次放电比容量分别为162.2和172.6 m Ah/g,循环3周后容量保持率分别为96.73%和94.62%。材料还表现出良好的倍率性能。展开更多
Layered Li(Ni0.5Mn0.5)1-xMxO2 (M=Ti, Al; x=0, 0.02) cathode materials for lithium-ion batteries were synthesized by one step solid-state method using Ni(OH)2, MnCO3, Li2CO3, TiO2 and Al(OH)3 as starting materials. The...Layered Li(Ni0.5Mn0.5)1-xMxO2 (M=Ti, Al; x=0, 0.02) cathode materials for lithium-ion batteries were synthesized by one step solid-state method using Ni(OH)2, MnCO3, Li2CO3, TiO2 and Al(OH)3 as starting materials. The effect of Ti and Al doping on the structure and electrochemical performance of Li(Ni0.5Mn0.5)1-xMxO2 (M=Ti, Al; x=0, 0.02) has been investigated. LiNi0.5Mn0.5O2, Li(Ni0.5Mn0.5)0.98Ti0.02O2 and Li(Ni0.5Mn0.5)0.98Al0.02O2 delivered 149 mAh·g-1, 160 mAh·g-1, 164 mAh·g-1, respectively, at a current of 20 mA·g-1 between 2.5 V and 4.3 V at room temperature, and remained 86%, 91%, 91% of the initial discharge capacity respectively after 30 cycles. AC impedance studies show that Ti and Al doping in Li(Ni0.5Mn0.5)1-xMxO2 (M=Ti, Al; x=0, 0.02) decreased the resistance of charge transfer Rct of cathode materials.展开更多
文摘采用高温固相法烧结制备得到正极材料Li Ni0.5Co0.2Mn0.3O2,通过X射线衍射(XRD)、扫描电镜(SEM)以及循环伏安(CV)、交流阻抗(EIS)等电化学性能测试手段,探讨高温烧结工艺中不同锂源对材料结构、形貌及电化学性能的影响,结果表明,采用Li OH作为锂源合成的材料与采用其他锂源相比,具有较好的层状结构和电化学性能.该材料在0.1C倍率下的首次充放电容量和库伦效率较高(172.7 m Ah/g,89.08%),在0.5C、1C倍率下循环50次后,材料的放电容量仍保持在144.5 m Ah/g和136.2 m Ah/g.
文摘采用化学共沉淀法预先合成球形前驱体Ni0.5Co0.2Mn0.3（OH）2,再与锂源共混后高温煅烧合成高容量正极材料Li Ni0.5Co0.3Mn0.2O2。探讨了不同烧结制度对材料结构性能的影响。X射线衍射（XRD）结果表明,产物结构为α-Na Fe O2型层状结构。扫描电子显微镜（SEM）显示材料具有良好的球形形貌。测试材料的电化学性能,在2.75~4.20 V和2.75~4.35 V充放电截止电压,0.5 C充放电电流下,首次放电比容量分别为162.2和172.6 m Ah/g,循环3周后容量保持率分别为96.73%和94.62%。材料还表现出良好的倍率性能。
文摘Layered Li(Ni0.5Mn0.5)1-xMxO2 (M=Ti, Al; x=0, 0.02) cathode materials for lithium-ion batteries were synthesized by one step solid-state method using Ni(OH)2, MnCO3, Li2CO3, TiO2 and Al(OH)3 as starting materials. The effect of Ti and Al doping on the structure and electrochemical performance of Li(Ni0.5Mn0.5)1-xMxO2 (M=Ti, Al; x=0, 0.02) has been investigated. LiNi0.5Mn0.5O2, Li(Ni0.5Mn0.5)0.98Ti0.02O2 and Li(Ni0.5Mn0.5)0.98Al0.02O2 delivered 149 mAh·g-1, 160 mAh·g-1, 164 mAh·g-1, respectively, at a current of 20 mA·g-1 between 2.5 V and 4.3 V at room temperature, and remained 86%, 91%, 91% of the initial discharge capacity respectively after 30 cycles. AC impedance studies show that Ti and Al doping in Li(Ni0.5Mn0.5)1-xMxO2 (M=Ti, Al; x=0, 0.02) decreased the resistance of charge transfer Rct of cathode materials.
