Electrostatic Quadrupole Plasma Mass Spectrometer Measurements During Thin Film Depositions Using Simultaneous Matrix Assisted Pulsed Laser Evaporation And Magnetron Sputtering,
2010
Air Force Research Laboratory
Electrostatic Quadrupole Plasma Mass Spectrometer Measurements During Thin Film Depositions Using Simultaneous Matrix Assisted Pulsed Laser Evaporation And Magnetron Sputtering, Chad N. Hunter, Michael H. Check, Christopher Muratore, Andrey A. Voevodin
Chemical and Materials Engineering Faculty Publications
A hybrid plasma deposition process, combining matrix assisted pulsed laser evaporation (MAPLE) of carbon nanopearls (CNPs) with magnetron sputtering of gold was investigated for growth of composite films, where 100 nm sized CNPs were encapsulated into a gold matrix. Composition and morphology of such composite films was characterized with x-ray photoelectron spectroscopy, scanning electron microscopy, and transmission electron microscopy (TEM) analysis. Carbondeposits on a gold magnetron sputter target and carbon impurities in the gold matrices of depositedfilms were observed while codepositing from gold and frozen toluene-CNP MAPLE targets in pure argon. Electrostatic quadrupole plasma analysis was used to determine that …
Maximizing The Life Of A Lithium-Ion Cell By Optimization Of Charging Rates,
2010
University of South Carolina
Maximizing The Life Of A Lithium-Ion Cell By Optimization Of Charging Rates, Saeed Khaleghi Rahimian, Sean Rayman, Ralph E. White
Faculty Publications
Using a dynamic optimization method, the optimum charge currents as a function of cycle number during cycling for the lithium-ion cell are obtained. A single particle physics-based model, which includes capacity fade, was applied to simulate the cell performance under low earth-orbit (LEO) cycling conditions. Useful cell life is defined as the number of cycles before the end of discharge voltage drops below 3.0 V or the cell discharge capacity becomes less than 20% of the original discharge capacity. The simulated useful cell life can be increased by ∼29.28% by varying the charge current.
Theoretical Analysis Of Stresses In A Lithium Ion Cell,
2010
University of South Carolina
Theoretical Analysis Of Stresses In A Lithium Ion Cell, Sindhuja Renganathan, Godfrey Sikha, Shriram Santhanagopalan, Ralph E. White
Faculty Publications
A mathematical model to simulate the generation of mechanical stress during the discharge process in a dual porous insertion electrode cell sandwich comprised of lithium cobalt oxide and carbon is presented. The model attributes stress buildup within intercalation electrodes to two different aspects: changes in the lattice volume due to intercalation and phase transformation during the charge/discharge process. The model is used to predict the influence of cell design parameters such as thickness, porosity, and particle size of the electrodes on the magnitude of stress generation. The model developed in this study can be used to understand the mechanical degradation …
