Search

Your search keyword '"Feng, Huihua"' showing total 258 results
Start Over Author "Feng, Huihua"
258 results on '"Feng, Huihua"'

2. Li-ion solvation structure at electrified solid–liquid interface: Understanding solvation structure dynamics and its role in electrochemical energy storage through binary ethylene carbonate and dimethyl carbonate solvent.

Author

Hamza, Muhammad, Mei, Bing-Ang, Liao, Ridong, Feng, Huihua, Zuo, Zhengxing, and Xiong, Rui

Subjects
NEGATIVE electrode, ENERGY storage, LITHIUM ions, ETHYLENE carbonates, PERMITTIVITY
Abstract

Binary solvent electrolytes can provide interpretations for designing advanced electrolytes of next generation batteries. This study investigates the adsorption mechanisms of solvated lithium ions in binary solvents near charged electrodes. Molecular dynamic simulations are performed for lithium hexafluorophosphate (LiPF6) in ethylene carbonate and dimethyl carbonate (EC:DMC) solvent sandwiched between two electrodes. Results show that lithium ions form a tetrahedral solvation structure with two EC and two DMC molecules. The solvated lithium ion shows anti-electrostatic interaction with electrodes. This can be attributed to the electrostatic attraction of the polar end of the DMC molecule, which keeps the cation anchored to the positive electrode. Meanwhile, the solvation structure adopts a fix orientation at the negative electrode, which leads to unchanged electrostatic interaction at high charge density. Finally, EC molecules are swapped by DMC molecules near the negative electrode at high charge density. This leads to a decrease in local relative permittivity and, therefore, a decrease in differential capacitance. The differential capacitance of the positive electrode continuously decreases with increasing charge density. This is caused by the partial anchoring of solvent molecules holding the cations, which cancels the adsorption of anions near the positive electrode. This study provides insights into designing better electrolytes for efficient battery performance. [ABSTRACT FROM AUTHOR]

Published
2024
Full Text
View/download PDF

48. Numerical Investigation on the Indicated Mean Effective Pressure and Integral Heat Release Rate Variations under Different Key Operating Parameters of a Spark‐Ignited Free Piston Engine Generator.

Author

Liu, Yong, Jia, Boru, Yang, Zixuan, Zhang, Zhiyuan, Liu, Chang, Wang, Wei, Feng, Huihua, Zuo, Zhengxing, Roskilly, Tony, and Quah, Hock Jin

Subjects
FREE piston engines, HYBRID power, ENERGY conversion, COMBUSTION, ENGINES
Abstract

Free‐piston engine generator is a new type of hybrid power device and is regarded as the next‐generation energy conversion device which can replace the traditional internal combustion engine. This paper focused on the combustion stability and combines experimental results to study the key factors affecting the stability of the free‐piston engine, such as ignition time, intake pressure, equivalence ratio, and operating frequency. The simulation results showed that as the ignition advance angle increased, the indicated mean effective pressure increased significantly and the coefficient of variation of the indicated mean effective pressure was effectively reduced from 15.55% to 1.02% as the advance in ignition time from −15 to −30°ECA. When the intake pressure was increased to 1.2 bar, the average value of indicated mean effective pressure reached about 5.15 bar. When the equivalence ratio was in the range of 1.0–1.4, the coefficient of variation of the indicated mean effective pressure can be kept below 10%. The indicated mean effective pressure decreased monotonically from 4.79 to 3.62 bar, and the coefficient of variation increased by five times as the engine speed increased as the engine speed increased from 1,000 to 2,500 RPM. [ABSTRACT FROM AUTHOR]

Published
2024
Full Text
View/download PDF

Catalog

Books, media, physical & digital resources
See catalog results