Li has garnered enormous attention for next-generation Limetal batteries owing to its remarkable theoretical capacity.Unfortunately,as an anode,Li suffers from serious safety issues and fast capacity fading due to the...Li has garnered enormous attention for next-generation Limetal batteries owing to its remarkable theoretical capacity.Unfortunately,as an anode,Li suffers from serious safety issues and fast capacity fading due to the formation of Li dendrites,which hinders the practical application of Li anode.Herein,a LiAlO_(2)-PVDF composite modification layer is fabricated on the surface of Li metal to enhance its stability and electrochemical performance.Benefitting fromthe synergetic effects of high Li+conductivity,high Li+transference number,excellent mechanical properties,superior chemical durability,and compactness of the modification layer,the LiAlO_(2)-PVDF@Li electrode delivers an ultra-long lifespan and a high capacity retention rate in the LiAlO2-PVDF@Li│LiFePO_(4) full cell.The proposed strategy provides a new alternative anode for Li metal batteries with high performance and scalable production.展开更多
The transition location of a boundary layer depends on the amplitude and characteristic of initial disturbances. The larger the amplitude and the amplification rate of the initial disturbances are,the more upstream th...The transition location of a boundary layer depends on the amplitude and characteristic of initial disturbances. The larger the amplitude and the amplification rate of the initial disturbances are,the more upstream the transition location is. However,the environment surrounding the flying vehicle is variable,so the amplitude and characteristic of the disturbances triggered in the boundary layer through receptivity are also variable. In this paper,how the transition location varies in response to the variation of the initial disturbance amplitudes is studied by using direct numerical simulation. The results show that if the initial disturbance amplitudes become smaller,the transition location moves downstream correspondingly,but there is a time delay compared to the time of arrival of the disturbances with reduced amplitudes. Moreover,the speed of moving downstream is appreciably lower than the propagation speed of the disturbances. On the other hand,if the amplitudes of the initial disturbances recover their original value,the transition would immediately take place whenever the disturbances reach the former transition location,but the laminar flow between the new and old transition locations would not become turbulent immediately. Theoretical explanations are provided based on the transition mechanism found by our group.展开更多
基金National Key Research and Development Program of China,Grant/Award Number:2017YFA0701001Fundamental Research Founds for the CentralUniversities,Grant/Award Number:ZYGX2019J024National Natural Science Foundation of China,Grant/Award Number:52002052。
文摘Li has garnered enormous attention for next-generation Limetal batteries owing to its remarkable theoretical capacity.Unfortunately,as an anode,Li suffers from serious safety issues and fast capacity fading due to the formation of Li dendrites,which hinders the practical application of Li anode.Herein,a LiAlO_(2)-PVDF composite modification layer is fabricated on the surface of Li metal to enhance its stability and electrochemical performance.Benefitting fromthe synergetic effects of high Li+conductivity,high Li+transference number,excellent mechanical properties,superior chemical durability,and compactness of the modification layer,the LiAlO_(2)-PVDF@Li electrode delivers an ultra-long lifespan and a high capacity retention rate in the LiAlO2-PVDF@Li│LiFePO_(4) full cell.The proposed strategy provides a new alternative anode for Li metal batteries with high performance and scalable production.
基金was supported by the National Natural Science Foundation of China (Grant Nos. 10632050 and 90716007)the National Basic Research Program of China (Grant No. 2009CB724103)the Specialized Research Fund for the Doctoral Program of Higher Education
文摘The transition location of a boundary layer depends on the amplitude and characteristic of initial disturbances. The larger the amplitude and the amplification rate of the initial disturbances are,the more upstream the transition location is. However,the environment surrounding the flying vehicle is variable,so the amplitude and characteristic of the disturbances triggered in the boundary layer through receptivity are also variable. In this paper,how the transition location varies in response to the variation of the initial disturbance amplitudes is studied by using direct numerical simulation. The results show that if the initial disturbance amplitudes become smaller,the transition location moves downstream correspondingly,but there is a time delay compared to the time of arrival of the disturbances with reduced amplitudes. Moreover,the speed of moving downstream is appreciably lower than the propagation speed of the disturbances. On the other hand,if the amplitudes of the initial disturbances recover their original value,the transition would immediately take place whenever the disturbances reach the former transition location,but the laminar flow between the new and old transition locations would not become turbulent immediately. Theoretical explanations are provided based on the transition mechanism found by our group.
