Hello, A new project on the LCRC cluster has been requested. Please forward the information on to the LCRC Allocation sub-committee. Applicant's name: John J. Low Applicant's institution: ANL Applicant's division: CELS Project Name: Scienomics Project title: A Molecular Model of Microporous Silicon Anodes Associated funding: Scienomics, Inc. Other Systems: Science: In previous phases of the project, a suitable simulation protocol for modeling the nanoporous structure of Raney Ni catalytic systems was established. The protocol was applied and validated on an alloy precursor with equal weight percentages (wt%) of Ni and Al which belongs to the industrially most widely used precursors. We then studied the influence of the initial alloy composition, the final Aluminum content or the precursor crystal structure on the porosity and density of Raney Nickel. This simulation protocol is generally applicable for modeling nanoporous materials. In the last years, these types of materials have been attracting much attention in the area of energy storage. To overcome the dependence on fossil fuels and because of the necessity to move towards renewable and sustainable energy resources, efficient energy storage systems become more and more important. Due to demanding requirements of industry and consumers on competitively viable energy storage technologies, it is crucial to understand and know the underlying storage mechanisms. Porous silicon anode is a very promising electrode in lithium ion batteries due to its very high capacity. However, such electrode present a major drawback, it experiences large volume changes during charge and discharge inducing pulverization of the electrode. To solve that problem these electrodes are carbon coated. Project description: Preparatory simulations were performed on such systems in order to adapt previous simulation workflow to this new material. A new workflow was defined using building and simulation engines available within MAPS Platform. Pores of desired radii were created along 100 direction of silicon anode. They were then simulated at higher temperature (300°C) before being quenched and equilibrated at 20°C. This protocol, allowed to well equilibrate the position of the atoms at the pore surface. Then different carbon coated approaches were tested: pore filled with different number of carbon atoms randomly placed, then equilibrated, carbon nanotube coated pores, atomic layer deposition of carbon on pore surface… This system was then submitted again to the previously defined protocol. Figure 1 [http://www.mcs.anl.gov/~jlow/scienomics/2016_allocation/Figure_1.png] presents examples of final structure of carbon coated porous silicon anode. Preliminary results show that carbon coating has an influence on the mechanical properties of the porous silicon anode which could therefore further explain the stability of the electrode once coated. In the next phase we plan to study two distinct aspects of the microporous silicon anode systems. It has previously been shown experimentally that carbon coating was stabilizing silicon anode upon Lithium cycling. In the first part of this phase we will therefore study the influence of carbon on the stability (structural, mechanical, thermal) of the silicon pore. We will also investigate the influence of different pore parameters such as the pore diameter or the wall size between two pores on these properties. In that scope, the previously mentioned protocol will be applied to generate the initial system conformations which will be energetically characterized. Stress-strain simulations will be performed in order to estimate Bulk and Young’s moduli of the systems. Finally temperature range will be used to understand the thermal stability of these systems. We believe that these different simulations will allow us the influence of carbon coating on the stability of the silicon anode. If the initial system generation can be done using relatively low simulations times (about 1 ns). Much longer simulations (about 20 ns) have to be performed for both the mechanical and thermal properties. One simulation of such system for 20 ns takes about 20h on 32 cores which represents about 640 core-hour. We believe that many different simulations will have to be ran for each system generated (1 simulation for the Young’s moduli on each direction (3 simulations in total), 1 simulation for the Bulk modulus and 1 simulation for the thermal stability) and we plan to generate several different initial systems (at least 3 different pore size, 3 different wall size and 3 different carbon coating approaches) which represent more than 100 simulations to be run. 100,000 core-hour will therefore be needed for this part of the project. The second part of the project we plan to study the influence of carbon coating on lithium adsorption and diffusion in silicon anode. For that both force field and ab-initio simulation will be used. Indeed a ReaxFF potential exists for simulating such systems. Reactive MD simulations will therefore be performed with and different amount of lithium and different amorphous anode systems (coated or not). We expect to run at least 1 ns simulations to see lithium diffusion during molecular dynamic. Additionally geometry optimization using periodic ab-initio simulation engine Quantum Espresso will be used to look at the different adsorption sites and diffusion mechanisms of lithium on both coated and non-coated silicon anodes. Such simulations are highly time demanding and another 100,000 core-hour would therefore be needed for this part of the project. This project will be using LAMMPS and Quantum Espresso. Both programs scale to thousands of cores for large unit cells. There will be four project members John J. Low from Argonne and the following three scientist from Scienomics. Biography of Relevant Members Dr. Robin Chaudret, Research Scientist at Scienomics, has a PhD in Computational Chemistry from the Université Pierre et Marie Curie of Paris. He has been doing research in the fields of organic, organometallic and bio chemistry. He applied and developed various tools to analyze and simulate the structure and reactivity of different systems. His ability to perform multiscale simulations (Quantum, Classical and QM/MM) allows him to cover a broad range of research areas such as homogeneous and heterogeneous catalysis, biochemistry or bioinspired chemistry, surfaces, etc. During his PhD and postdoc experiences he developed several collaborations with Paris or Montpelier Universities in France and Duke University in North Carolina and organized and participated to different meetings and published several papers. Dr. Sabine Schweizer, Senior Scientist at Scienomics has a Ph. D. in Theoretical Chemistry from University of Tuebingen, Germany. Her work experience is in the area of applying quantum chemical methods to large and small molecules. Her experience is particularly useful in the areas of homogenous and heterogenous catalysis, where energetics and dynamics play an important role in the reactions. She has experience working with multiscale hybrid methods combining quantum chemical and classical methods which makes her particularly versatile in applying Scienomics’ multiscale, multiparadigm MAPS platform to study hard materials such as surfaces, coatings, semiconductors, solar cells, etc. Dr. Lalitha Subramanian, Chief Scientific Officer and VP of Services has 18 years of experience providing insight into chemical systems and processes that are of critical interest to industry. Following her Ph. D. in Chemistry, her post-doctoral work was with Prof. Roald Hoffmann (Nobel Laureate) at Cornell University. She has been a leading architect of solutions in the areas of alternate energy, catalysis, materials design, and process optimization. She has worked on numerous proprietary projects for diverse companies and in this pursuit; she has delivered product enhancements, process optimization and cost savings to her customers. Lalitha maintains a broad range of partnerships in oil & gas, chemical, personal care, materials, semiconductors, automotive, aerospace, and pharmaceutical industries. She has co-authored a book on software techniques used in Materials Science published by CRC Press, 2005. She continues to present invited lectures and has numerous scientifi c publications. Industry partnership: About Scienomics Scienomics was established in 2004 and with selected partnerships with the best-of-the-breed (e.g.: Sandia National Labs, Max Planck Institute, Fraunhofer Institute, University of Illinois, Demokritos, University of Shanghai), Scienomics’s MAPS platform offers a unique and powerful blend of multiscale and multiparadigm modeling and simulation modules. With high quality science and industrial solution oriented applied research, Scienomics has garnered collaborative projects with companies in the areas of energy and green chemistry, alternate fuels, catalysis, polymers, biodefense, auto exhaust, etc. This exploratory project with Scienomics is intended to lead to collaborations with other industrial partners. Project URL: http://scienomics.com/references/collaborators-and-advisors/dr-john-low Requested allocation: 200000 Q1: 50000 Q2: 50000 Q3: 50000 Q4: 50000 Justification: Storage requirements: The requester has used undetermined amount hours of their initial startup project. In addition to approving an initial amount, please specify a Category and Subcategory for this project. For a list of the current selection of approved categories, please see: https://wiki.lcrc.anl.gov/wiki/Processes/Categories Once the Allocation committee has approved the project, please go to the Project Management page to create it: https://accounts.lcrc.anl.gov/projects.php Thank You, The LCRC Accounts System