The potentiostatic intermittent titration technique(PITT)is widely used to determine the diffusion coefficient of ions in electrode materials for rechargeable batteries such as lithium-ion or sodium-ion batteries,pred...The potentiostatic intermittent titration technique(PITT)is widely used to determine the diffusion coefficient of ions in electrode materials for rechargeable batteries such as lithium-ion or sodium-ion batteries,predicated on the assumption that the insertion/extraction of ions in the host materials is governed by diffusion.However,in practical scenarios,the electrochemical process might be dominated by interfacial reaction kinetics rather than diffusion.The present work derives analytical equations for electric current by considering the finite interfacial reaction kinetics and small overpotentials during PITT measurements and further studies the chemical stress field induced by the interfacial reaction-controlled ion insertion.The exchange current density(j_(0))can be ascertained using the analytical equation,which dictates the magnitude and decay rate of the electric current during a PITT process.The electric current decays more rapidly,and consequently,the lithium concentration reaches equilibrium faster for larger values of j_(0).The magnitude of the chemical stress is independent of j_(0) but depends on the overpotential.展开更多
To help the forecast of cold weather activity, the cold weather process in the North China from October 20 to 23, 2020 was analyzed by the methods of utilizing statistical analysis, such as composite, differential ana...To help the forecast of cold weather activity, the cold weather process in the North China from October 20 to 23, 2020 was analyzed by the methods of utilizing statistical analysis, such as composite, differential analysis and correlation analysis, and by using the data from the National Meteorological Information Center of China, the National Climate Center of China and the NECP data from NOAA Physical Sciences Laboratory. The results show that: 1) the cold air started from Siberia, took the east path to move southward, and finally affected most part of North China. 2) Almost no obvious weather occurred during the process. 3) The cold air mainly moved along with the form and development of the trough and ended when the trough got weaken.展开更多
基金supported by the National Natural Science Foundation of China(No.12374003)the Guangdong Basic and Applied Basic Research Foundation(No.2024A1515030256)the Shenzhen Science and Technology Program(Grant Nos.JCYJ20220531095208019 and GXWD20231129103124001).
文摘The potentiostatic intermittent titration technique(PITT)is widely used to determine the diffusion coefficient of ions in electrode materials for rechargeable batteries such as lithium-ion or sodium-ion batteries,predicated on the assumption that the insertion/extraction of ions in the host materials is governed by diffusion.However,in practical scenarios,the electrochemical process might be dominated by interfacial reaction kinetics rather than diffusion.The present work derives analytical equations for electric current by considering the finite interfacial reaction kinetics and small overpotentials during PITT measurements and further studies the chemical stress field induced by the interfacial reaction-controlled ion insertion.The exchange current density(j_(0))can be ascertained using the analytical equation,which dictates the magnitude and decay rate of the electric current during a PITT process.The electric current decays more rapidly,and consequently,the lithium concentration reaches equilibrium faster for larger values of j_(0).The magnitude of the chemical stress is independent of j_(0) but depends on the overpotential.
文摘To help the forecast of cold weather activity, the cold weather process in the North China from October 20 to 23, 2020 was analyzed by the methods of utilizing statistical analysis, such as composite, differential analysis and correlation analysis, and by using the data from the National Meteorological Information Center of China, the National Climate Center of China and the NECP data from NOAA Physical Sciences Laboratory. The results show that: 1) the cold air started from Siberia, took the east path to move southward, and finally affected most part of North China. 2) Almost no obvious weather occurred during the process. 3) The cold air mainly moved along with the form and development of the trough and ended when the trough got weaken.
