Li4Ti5O12（LTO）/carbon nanotubes（CNTs） composite material is synthesized based on a solid-state method by sand-milling, spray-drying and calcining at 850 8C under N2 flow. The LTO/CNTs samples with1 wt% and 3 wt% w...Li4Ti5O12（LTO）/carbon nanotubes（CNTs） composite material is synthesized based on a solid-state method by sand-milling, spray-drying and calcining at 850 8C under N2 flow. The LTO/CNTs samples with1 wt% and 3 wt% weight ratio of CNTs addition and the pristine LTO sample are prepared. The rate performance and the thermal stability of these samples are investigated based on Li Mn2O4（LMO）/LTO full-cell. The results show that the weight ratio of CNTs addition has distinct effect on LTO performances.The composite materials of LTO composited CNTs have better performance at high-rate due to the intercalation enhancement by conductive network of CNTs. At second, the overcharging temperature response of the cell＇s surface with 1 wt% CNTs addition is the lowest. The particle size distribution is measured and the most uniform particles are obtained with 1 wt% CNTs addition. This trend could explain that the medium quantity of CNTs is optimal to improve the heat and mass transfer and prevent the problems of crystallite growing interference and aggregation during the calcination process.展开更多
The effect of nanoparticle aggregation on the thermal conductivity of nanocomposites or nanofluids is typically nonnegligible. A universal model（Maxwell model） including nanoparticle aggregation is modified in order...The effect of nanoparticle aggregation on the thermal conductivity of nanocomposites or nanofluids is typically nonnegligible. A universal model（Maxwell model） including nanoparticle aggregation is modified in order to predict the thermal conductivity of nanocomposites more accurately. The predicted thermal conductivities of silica and titania nanoparticle powders are compared first with that measured by a hot-wire method and then with those in previous experimental works.The results show that there is good agreement between our model and experiments, and that nanoparticle aggregation in a nanocomposite enhances the thermal conductivity greatly and should not be ignored. Because it considers the effect of aggregation, our model is expected to yield precise predictions of the thermal conductivity of composites.展开更多
基金supported by the National Major Scientific Equipment R&D Project(No.ZDYZ2010-2)the National Natural Science Foundation of China(No.51307165)
文摘Li4Ti5O12（LTO）/carbon nanotubes（CNTs） composite material is synthesized based on a solid-state method by sand-milling, spray-drying and calcining at 850 8C under N2 flow. The LTO/CNTs samples with1 wt% and 3 wt% weight ratio of CNTs addition and the pristine LTO sample are prepared. The rate performance and the thermal stability of these samples are investigated based on Li Mn2O4（LMO）/LTO full-cell. The results show that the weight ratio of CNTs addition has distinct effect on LTO performances.The composite materials of LTO composited CNTs have better performance at high-rate due to the intercalation enhancement by conductive network of CNTs. At second, the overcharging temperature response of the cell＇s surface with 1 wt% CNTs addition is the lowest. The particle size distribution is measured and the most uniform particles are obtained with 1 wt% CNTs addition. This trend could explain that the medium quantity of CNTs is optimal to improve the heat and mass transfer and prevent the problems of crystallite growing interference and aggregation during the calcination process.
基金Project supported by the Fundamental Research Funds for the Central Universities of China(Grant No.2015XKMS062)
文摘The effect of nanoparticle aggregation on the thermal conductivity of nanocomposites or nanofluids is typically nonnegligible. A universal model（Maxwell model） including nanoparticle aggregation is modified in order to predict the thermal conductivity of nanocomposites more accurately. The predicted thermal conductivities of silica and titania nanoparticle powders are compared first with that measured by a hot-wire method and then with those in previous experimental works.The results show that there is good agreement between our model and experiments, and that nanoparticle aggregation in a nanocomposite enhances the thermal conductivity greatly and should not be ignored. Because it considers the effect of aggregation, our model is expected to yield precise predictions of the thermal conductivity of composites.
