Hierarchical porous LiNi1/3Co1/3Mn1/3O2 with yolk–shell-like architecture as stable cathode material for lithium-ion batteries

Jung

ACS Appl. Mater. Interfaces

et al. 2021

Nickel-rich lithium metal oxide cathode materials have recently be en highlighted as next-generation cathodes for lithium-ion batteries. Nevertheless, their relatively high surface reactivity must be controlled, as fading of the cycling retention occurs rapidly in the cells. This paper proposes functionalized nickel-rich lithium metal oxide cathode materials by a multipurpose nanosized inorganic materialtitanium silicon oxidevia a simple thermal treatment process. We examined the topologies of the nano-titanium silicate-functionalized nickel-rich lithium metal oxide cathodes with scanning electron microscopy and quantitatively analyzed their improved mechanical properties using microindentation. The cell containing nickel-rich lithium metal oxide cathodes suffered from poor cycling behavior as the electrolytes persistently decomposed; however, this behavior was effectively inhibited in the cell by nano-titanium silicate-functionalized nickel-rich lithium metal oxide cathodes. Further ex situ analyses indicated that the particle hardness of the nano-titanium silicate-functionalized nickel-rich lithium metal oxide cathode materials was maintained, and decomposition of the electrolyte by the dissolution of transition metals was thoroughly inhibited even after 100 cycles. Based on these results, we concluded that the use of nano-titanium silicate as a coating material for nickel-rich lithium metal oxide cathode materials is an effective way to enhance the cycling performance of lithium-ion batteries.

Section: Resultssupporting

confidence: 86%

Interface-Stabilized Layered Lithium Ni-Rich Oxide Cathode via Surface Functionalization with Titanium Silicate

Jung

ACS Appl. Mater. Interfaces

et al. 2021

Advances in Materials Science and Engineering

“…Professor P. O. Fanger of Denmark proposed a comprehensive comfort index based on the following: the parameters that determine the comfort state of the human body have nothing to do with the environment, but only with the human body. Fanger believes that what a person feels is not the temperature of the surrounding air, but the temperature of his own skin [22]. On the basis of theory, Fanger conducted experiments with subjects and then used regression analysis to determine the relationship between the average human skin temperature, sweat evaporation heat loss, and metabolic rate:…”

Section: Fanger Heat Balance Equationmentioning

confidence: 99%

Building Thermal Comfort Research Based on Energy-Saving Concept

Xue

Zhao

2021

Under the trend of building green and comfortable development, effective control of building energy consumption has become one of the problems that countries are actively facing to solve. People’s demand for residential buildings has changed from the past survival type to a comfortable and livable type. The high level of heating energy consumption is worthy of in-depth study. In order to reduce energy consumption, realize the mapping of energy-saving concepts in buildings, and understand the energy consumption of different building materials and the influence of external factors on human thermal comfort, this book has conducted research on building thermal comfort based on energy-saving concepts. First of all, this article introduces the concept and application mode of energy-saving concepts in buildings and the concept of thermal comfort and the SET index of standard effective temperature, including the two-node model and the algorithm involved in the Fanger heat balance equation. In the experimental part, a model based on the concept of energy saving was designed to predict and analyze the energy consumption and thermal comfort effects of the building. In the analysis part, a comprehensive analysis of the effects of temperature, humidity, wind speed, and gender on thermal comfort, methods to improve thermal comfort, cumulative load changes with the heat transfer coefficient of windows, and the effects of windows of different materials on energy consumption was performed. At the same temperature, the wind speed is different, and the degree of heat sensation is also different. When the wind speed is 0.18 m/s and the temperature is 28°C, the thermal sensation is 0.32, and the human sensation is close to neutral. When the wind speed increases to 0.72 m/s, the heat sensation drops to −0.45, and the human body feels neutral and cool. It can be seen that the increase in wind speed has a certain compensation effect on the thermal sensation of the human body. When the wind speed does not change, increase the air temperature. For example, when the wind speed is 0.72 m/s, the temperature is 28°C, and the thermal sensation is −0.45, and when the temperature is increased to 29°C, the thermal sensation is 0.08, which shows that the temperature is improving the thermal sensation of the human body which has a certain offsetting effect. By studying the thermal comfort of buildings based on energy-saving concepts, it is possible to obtain the effect of external factors on thermal comfort, thereby optimizing building materials and using building materials with lower heat transfer coefficients to reduce heating energy consumption.

“…Yolk-shell could be a useful architecture in dealing with these problems, as electrochemically active yolk material can expand and shrink without being contact with the aggressive electrolyte under the protection of the inert shell. [341] Even if the yolk pulverises, the active materials will still be confined in the space provided by the shell, ensuring good electrical contact. [342] Transition metal oxides with yolk-shell nanostructure have been synthesised as well, which can accommodate large volume variation during cycles.…”

Section: Unique Nanostructuresmentioning

confidence: 99%

“…The situation may become even worse when the devices are operated at high current densities. Yolk‐shell could be a useful architecture in dealing with these problems, as electrochemically active yolk material can expand and shrink without being contact with the aggressive electrolyte under the protection of the inert shell . Even if the yolk pulverises, the active materials will still be confined in the space provided by the shell, ensuring good electrical contact .…”

Section: Acceleration Of Electrochemical Kinetics By Nanotechnologymentioning

confidence: 99%

Recent Developments of Nanomaterials and Nanostructures for High‐Rate Lithium Ion Batteries

Zhou

et al. 2020

ChemSusChem

techniques, based on either electrochemical or radiology methodologies, are covered as well. In addition, state-of-the-art research findings are provided to illustrate the effect of nanomaterials and nanostructures in promoting the rate performance of lithium ion batteries. Finally, several challenges and shortcomings of applying nanotechnology in fabricating highrate lithium ion batteries are summarised.