采用氧化石墨烯(Graphene oxide,GO)与固相法制备的Li_2Ru_(0.6)Mn_(0.4)O_3复合得到Li_2Ru_(0.6)Mn_(0.4)O_3/GO复合电极材料,并利用X射线衍射(X-ray diffraction,XRD)、扫描电子显微镜(Scanning electron microscope,SEM)、透射电子...采用氧化石墨烯(Graphene oxide,GO)与固相法制备的Li_2Ru_(0.6)Mn_(0.4)O_3复合得到Li_2Ru_(0.6)Mn_(0.4)O_3/GO复合电极材料,并利用X射线衍射(X-ray diffraction,XRD)、扫描电子显微镜(Scanning electron microscope,SEM)、透射电子显微镜(Transmission electron microscope,TEM)和能谱仪(Energy dispersive spectrometer,EDS)分别对其晶体结构、形貌进行了表征。氧化石墨烯不仅可以改善Li_2Ru_(0.6)Mn_(0.4)O_3的导电性,而且可减小其在电解液中因溶解而发生的副反应。电化学测试表明:复合后电极材料的循环性能和倍率性能得到了明显的改善,200圈以后容量依然为初始容量的87.5%;5C大倍率的充放电后,电流密度回到0.1C时,容量保持在初始容量的95%以上。展开更多
LiNi1-xCoxO2 with x=0.1, 0.2, 0.3, 0.5 and 1 were prepared by co-precipitation of mixed solution of Ni- and Co-salt in NaOH. The structure of LiNi1-xCoxO2 was analyzed by XRD. The results show that the unit cell const...LiNi1-xCoxO2 with x=0.1, 0.2, 0.3, 0.5 and 1 were prepared by co-precipitation of mixed solution of Ni- and Co-salt in NaOH. The structure of LiNi1-xCoxO2 was analyzed by XRD. The results show that the unit cell constants a and c decrease as the Co content increases. Although the change of unit cell constants can reflect the substitution of Co ions with Ni ions in the lab, the splits of the pairs of (006), (102) and (108), (110) in the XRD pattern can not reflect the presence of Ni2+ in the lithium site.展开更多
利用超细旋转盘式砂磨机细化颗粒固相烧结法,合成锂离子电池正极材料Li Ni0.80Co0.15Al0.05O2。原料经过砂磨后,混合均匀,粒径达到纳米级。根据塔曼定理,混合均匀的微小粒径可以在相同的烧结温度下,提高烧结的强度。SEM、XRD分别表征NC...利用超细旋转盘式砂磨机细化颗粒固相烧结法,合成锂离子电池正极材料Li Ni0.80Co0.15Al0.05O2。原料经过砂磨后,混合均匀,粒径达到纳米级。根据塔曼定理,混合均匀的微小粒径可以在相同的烧结温度下,提高烧结的强度。SEM、XRD分别表征NCA材料的颗粒形貌和晶形结构。结果显示,通过细化颗粒烧结后的样品具有良好的形貌和层状结构。CV法测试样品的氧化还原性能,电池测试系统测试样品的电化学性能。测试结果显示,经过细化颗粒,在720℃合成的NCA材料具有良好的层状结构,018/110峰分裂明显。样品的电化学性能优良,0.2C下,首次放电容量达到182 m Ah?g?1,30次循环后容量保持率99.9%。1C下,首次放电容量153 m Ah?g?1,100次循环后容量保持率92.6%。展开更多
文摘采用氧化石墨烯(Graphene oxide,GO)与固相法制备的Li_2Ru_(0.6)Mn_(0.4)O_3复合得到Li_2Ru_(0.6)Mn_(0.4)O_3/GO复合电极材料,并利用X射线衍射(X-ray diffraction,XRD)、扫描电子显微镜(Scanning electron microscope,SEM)、透射电子显微镜(Transmission electron microscope,TEM)和能谱仪(Energy dispersive spectrometer,EDS)分别对其晶体结构、形貌进行了表征。氧化石墨烯不仅可以改善Li_2Ru_(0.6)Mn_(0.4)O_3的导电性,而且可减小其在电解液中因溶解而发生的副反应。电化学测试表明:复合后电极材料的循环性能和倍率性能得到了明显的改善,200圈以后容量依然为初始容量的87.5%;5C大倍率的充放电后,电流密度回到0.1C时,容量保持在初始容量的95%以上。
文摘LiNi1-xCoxO2 with x=0.1, 0.2, 0.3, 0.5 and 1 were prepared by co-precipitation of mixed solution of Ni- and Co-salt in NaOH. The structure of LiNi1-xCoxO2 was analyzed by XRD. The results show that the unit cell constants a and c decrease as the Co content increases. Although the change of unit cell constants can reflect the substitution of Co ions with Ni ions in the lab, the splits of the pairs of (006), (102) and (108), (110) in the XRD pattern can not reflect the presence of Ni2+ in the lithium site.
文摘利用超细旋转盘式砂磨机细化颗粒固相烧结法,合成锂离子电池正极材料Li Ni0.80Co0.15Al0.05O2。原料经过砂磨后,混合均匀,粒径达到纳米级。根据塔曼定理,混合均匀的微小粒径可以在相同的烧结温度下,提高烧结的强度。SEM、XRD分别表征NCA材料的颗粒形貌和晶形结构。结果显示,通过细化颗粒烧结后的样品具有良好的形貌和层状结构。CV法测试样品的氧化还原性能,电池测试系统测试样品的电化学性能。测试结果显示,经过细化颗粒,在720℃合成的NCA材料具有良好的层状结构,018/110峰分裂明显。样品的电化学性能优良,0.2C下,首次放电容量达到182 m Ah?g?1,30次循环后容量保持率99.9%。1C下,首次放电容量153 m Ah?g?1,100次循环后容量保持率92.6%。