MD Simulations of Fast Li-ion Battery Charging

Per Arne Rikvold, Florida State University, DMR 0802288

Li-ion batteries are an important portable energy source for applications ranging from mobile phones to electric cars. Among their advantages are low weight, relatively high voltage, and relatively low cost. However, charging times of several hours are required. In this work, which is a collaboration between the PI’s group and a group at Mississippi State University, an improved charging method is proposed and tested by Molecular Dynamics simulations. The method consists in applying an oscillating electric field to the cell in addition to the static charging field, and the simulations indicate that it may significantly reduce the required charging time.

I. Abou Hamad, M.A. Novotny, D.O. Wipf, P.A. Rikvold, Physical Chemistry Chemical Physics 12, 2740 (2010).

Cover of the journal PCCP, showing the simulated system with one Li ion intercalated

MD Simulations of Fast Li-ion Battery Charging

Per Arne Rikvold, Florida State University, DMR 0802288

Education: Three undergraduate students, two graduate students, and one postdoc were supported in part by this grant. International collaborations: 1. The PI spent one month in the Summer of 2010 as a visiting Professor in the Department of Physics, University of Tokyo, Japan. 2. Prof. Gloria M. Buendía from Universidad Simón Bolívar in Venezuela visited the PI’s group for collaborations, 2008, ’09 and ‘10. 3. Collaborated on research projects with various groups at The University of Tokyo, Japan, and McGill University and Université de Montréal, Canada.

Outreach: The PI demonstrates some of his LEGO physics creations at the FSUPhysics Department’s 2009 open house. For more on the LEGO project, see : http://www.physics.fsu.edu/users/rikvold/info/legostuff.html

Ecological and evolutionary systems can be seen as interacting multi-agent systems and studied by methods from statistical physics. The PI is collaborating with groups in Canada and Japan to utilize these analogies. The figure here shows a result from a collaboration with colleagues at Université de Montréal and McGill University in Canada. As the probabilitiy of migrating away from harsh envirnments increases, the model undergoes a nonequilibrium phase transition from a phase of low geographical similarity to one of high similarity.

E. Filotas, M. Grant, L. Parrott, P.A. Rikvold, Journal of Theoretical Biology 266, 419 (2010).

Upper: Spatial maps of similarity. Lower: Index of regional similarity.In the low-similarity phase, local diversity is low and regional diversity is high. In the high-similarity phase, local diversity is high and regional diversity is low.

Statistical Mechanics Modeling of Ecology and Evolution

Per Arne Rikvold, Florida State University, DMR 0802288

Statistical Mechanics Modeling of Ecology and Evolution

Per Arne Rikvold, Florida State University, DMR 0802288

Education: Three undergraduate students, two graduate students, and one postdoc were supported in part by this grant. International collaborations: 1. The PI spent one month in the Summer of 2010 as a visiting Professor in the Department of Physics, University of Tokyo, Japan. 2. Prof. Gloria M. Buendía from Universidad Simón Bolívar in Venezuela visited the PI’s group for collaborations, 2008, ’09 and ‘10. 3. Collaborated on research projects with various groups at The University of Tokyo, Japan, and McGill University and Université de Montréal, Canada.

Outreach: The PI demonstrates some of his LEGO physics creations at the FSUPhysics Department’s 2009 open house. For more on the LEGO project, see : http://www.physics.fsu.edu/users/rikvold/info/legostuff.html

Oxidation of carbon monoxide (CO) to carbon dioxide (CO2) on a catalytic surface is an extemely important industrial chemical reaction. One of its most crucial applications is in automobile catalytic converters. In this collaboration with Profs. Gloria M. Buendía and Erik Machado from Universidad Simón Bolívar in Venezuela, the PI considered the effects of coadsorption of CO and atomic O on the rate of CO2 production. It was found that the coadsorption permits CO2 production even at very low CO partial pressures, and that a high probability of coadsorption changes the drop in the production rate that occurs for high CO pressures from abrupt (a discontinuous nonequilibrium phase transition to a CO-poisoned phase) to gradual. This effect enables the reaction to take place (albeit at a reduced rate), even at high CO pressures.

Dependence of CO coverage (black), O coverage (red), and CO2 production rate(blue) on the CO partial pressure y. Thecoverages and production rate are significantly influenced by the coadsorptionof CO and O. G.M. Buendía, E. Machado, P.A. Rikvold, Journal of Chemical Physics 131, 184704 (2009).

Modeling of Catalytic CO Oxidation

Per Arne Rikvold, Florida State University, DMR 0802288

Modeling of Catalytic CO Oxidation

Per Arne Rikvold, Florida State University, DMR 0802288

Education: Three undergraduate students, two graduate students, and one postdoc were supported in part by this grant. International collaborations: 1. The PI spent one month in the Summer of 2010 as a visiting Professor in the Department of Physics, University of Tokyo, Japan. 2. Prof. Gloria M. Buendía from Universidad Simón Bolívar in Venezuela visited the PI’s group for collaborations, 2008, ’09 and ‘10. 3. Collaborated on research projects with various groups at The University of Tokyo, Japan, and McGill University and Université de Montréal, Canada.

Outreach: The PI demonstrates some of his LEGO physics creations at the FSUPhysics Department’s 2009 open house. For more on the LEGO project, see : http://www.physics.fsu.edu/users/rikvold/info/legostuff.html