Batteries and transportation applications
Department of Materials Science and Engineering,
Geballe Laboratory for Advanced Materials
Presentation Title: Nanotechnology Enabled Advanced Photovoltaics and Energy Storage (29.8 Mb)
Abstract: Photovoltaics and energy storage technologies are two of the most critical components for a renewable energy future. Significant performance enhancements and/or cost reductions are required to deploy these technologies at a large scale. To improve performance, maximizing the efficiency of charge carrier transport and separation, ion diffusion, light harvesting, and tuning the energetics are critical. To reduce costs, materials abundance and processing need to be considered. In the past twenty-year development of nanotechnology, the fundamental physical property and materials processing have been widely studied in nanomaterials including nanocrystals, nanotubes, and nanowires. Designing nanomaterials rationally offers such exciting opportunities for both photovoltaics and energy storage. In my lecture, I will present several examples. In energy storage, Si nanowires directly grown on metal collector substrates can result in 10 times higher specific charge capacity of carbon used in the existing lithium ion battery technology. Furthermore, core-shell Si nanowire design can enable super-high power operation. Porous nanowires can increase the energy density of supercapacitor electrodes by 10 fold to levels comparable to those in batteries. In photovoltaics, metal nanowires are explored as low-cost solution-processed transparent conducting electrodes. Amorphous Si nanocones are designed to be a good anti-reflection coating and absorber, which can result in significant improvement of power conversion efficiency. The pathways to incorporate these nanomaterials into the real technologies will be discussed.
GCEP: Professor Yi Cui is currently a principal investigator for two GCEP
efforts—"Battery Electrodes with Nanowire Architectures” in the area of
advanced transportation—and Nanostructured Materials for
High-Efficiency Thin Film Solar Cells" in the area of solar energy. He
is also currently a principal investigator for the GCEP exploratory
effort "Spectroscopic Characterization of Multi-Exciton Generation
Efficiency in Nano-Structured Materials," and was a principal
investigator for the completed GCEP exploratory effort
"Nanowire-Nanocrystal Multiexciton Solar Cells."
Biography: Yi Cui has been an Assistant Professor in the Department of Materials Science and Engineering at Stanford University since 2005. He leads a team of 25 PhD and postdoctoral scholars working on nanomaterials synthesis, electronic properties, solar cell, battery, memory, and biosensor devices. His most recent breakthrough was to realize Si nanowire lithium ion battery electrodes with 10 times higher specific charge capacity than carbon.
Professor Cui has received numerous honors, including the King Abdullah University of Science and Technology Investigator Award (2008), Office of Naval Research Young Investigator Award (2008), Mohr Davidow Ventures Innovators Award (2007), Terman Fellowship (2005), the Technology Review World Top Young Innovator Award (2004), Miller Research Fellowship (2003), Distinguished Graduate Student Award in Nanotechnology (Foresight Institute, 2002), Gold Medal of Graduate Student Award (Material Research Society, 2001).
Professor Cui received his BS degree at the University of Science and Technology of China in 1998 and his PhD at Harvard in 2002. From 2003-2005, he worked as a Miller Postdoctoral Fellow at the University of California, Berkeley.
Department of Mechanical Engineering
Presentation Title: Understanding the Path to High-Efficiency Chemical Engines (2.07 Mb)
Abstract: Devices that produce work from a chemical energy resource—engines, both stationary and for transportation—account for more than 75% of U.S. carbon emissions. Although engine efficiency has been the subject of intensive and continuous development, it remains well below theoretical limits, usually by more than a factor of two. Research conducted under GCEP sponsorship has shown that it is possible to take a systematic approach to understanding and improving engine efficiency. In this talk, we discuss fundamental limitations on engine efficiency, some common misconceptions about the same, and our current efforts to achieve high-efficiency internal combustion through the use of extreme compression.
GCEP: Professor Christopher Edwards is currently a principal investigator for the GCEP effort "Low Exergy Loss Chemical Engines." He was also a principal investigator for the GCEP effort "Development of Low-Irreversibility Engines," which was completed in August 2006. Edwards was the inaugural Deputy Director of GCEP for the project's first four years and is a former GCEP Research Theme Leader for Carbon Mitigation.
Biography: Professor Edwards completed Masters and PhD degrees at the University of California, Berkeley, while investigating plasma jet ignition processes for ultralean engine combustion. He was the first recipient of the Starkman Memorial Award at Berkeley, given to the outstanding graduate student in thermal sciences. In 1985, Dr. Edwards joined the technical staff at the Combustion Research Facility of Sandia National Laboratories. Focused initially in the areas of DISI and diesel engine research, then later in steady and transient sprays, Dr. Edwards worked at Sandia on experimental, theoretical, and diagnostic development components. In 1995, he was appointed a Distinguished Member of Technical Staff, the highest technical ranking at Sandia. In September of 1995, Dr. Edwards joined the Department of Mechanical Engineering at Stanford, in the thermosciences group. Here he is pursuing research in the areas of advanced energy and propulsion systems with ultra high efficiency and low greenhouse gas emissions, while teaching courses that range from introductory to advanced thermodynamics, energy systems, and engines.
Dr. Edwards has received the Tanasawa Award from the International Conference on Liquid Atomization and Sprays (1991), the Robert Marshall Award from the Institute of Liquid Atomization and Spray Systems (1994), and the Adams Award from Sandia National Laboratories, given for outstanding technical achievement at the Combustion Research Facility (1994). In 1998 he was selected as a Bing Fellow for outstanding undergraduate teaching. In 1999, he was selected as Teacher of the Year by the Society of Women Engineers and received the Phi Beta Kappa Undergraduate Teaching Prize. In 2002, he was appointed the John Henry Samter University Fellow in Undergraduate Education. In 2006, he received the Rudolf Kalman Award from the ASME Dynamic Systems and Control Division for the best paper in JDSMC in 2005. And in 2008, he received the Walter J. Gores Award—Stanford University’s highest award for teaching.
Microbial synthesis of biodiesel
Departments of Chemistry and Chemical Engineering, and, by courtesy, Biochemistry
Presentation Title: Microbial Synthesis of Biodiesel
Abstract: The goals of our ongoing GCEP efforts are two-fold:
(i) To identify and overcome barriers to efficient fatty acid biosynthesis in E. coli; and
(ii) To exploit the resulting engineered bacterium for the biosynthesis of new types of energy-dense biofuels.
To these ends, we have made significant progress along the following directions:
(i) We have established a cell-free system from E. coli that converts acetyl-CoA and related molecules into fatty acids. This cell-free system enables us to identify bottlenecks in fatty acid biosynthesis in a manner that is far more direct, rapid and quantitatively accurate than conventional molecular biological approaches;
(ii) By introducing a number of specific changes into the E. coli genome, we have considerably enhanced the fatty acid biosynthetic capacity of this bacterium; and
(iii) By transferring a complex fatty acid reductase from a plant into E. coli, we have demonstrated the in vivo conversion of endogenous fatty acids into fatty alcohols.
Future efforts are focused on developing a lab-scale microbial process that achieves practically useful productivity of fatty alcohols, and on demonstrating the feasibility of rationally fine-tuning fatty alcohol composition. Not only does this have implications for the existing 2bn tons/yr fatty alcohol market, but it could also foster the emergence of fundamentally new uses for fatty alcohols as transportation fuels.
GCEP: Professor Khosla is currently a principal investigator for the GCEP effort “Microbial Synthesis of Biodiesel.” His activities are focused on exploiting the considerable expertise of his laboratory in the area of microbial metabolism to attempt development of a practical fermentation process for a new kind of transportation fuel derived from renewable resources.
Biography: Chaitan Khosla is the Wells H. Rauser and Harold M. Petiprin Professor
at Stanford University in the Departments of Chemistry, Chemical
Engineering, and, by courtesy, Biochemistry. He received his PhD in
1990 at Caltech. After completing postdoctoral studies at the John
Innes Centre in the UK, he joined Stanford in 1992. Over the past two
decades, he has studied polyketide synthases as paradigms for modular
catalysis, and has exploited their properties for engineering novel
antibiotics. More recently, he has investigated celiac sprue
pathogenesis with the goal of developing therapies for this widespread
but overlooked disease.
Professor Khosla has co-authored over
230 publications and 50 U.S. patents, and is the recipient of several
awards and honors including the National Science Foundation Young
Investigator Award; the David and Lucile Packard Fellowship for Science
and Engineering; the Allan P. Colburn Award and the Professional
Progress Award from the American Institute of Chemical Engineers; the
Eli Lilly Award in Biological Chemistry, the Pure Chemistry Award, and
Arthur C. Cope Scholar Award from the American Chemical Society; and
the Alan T. Waterman Award from the National Science Foundation. He was
elected a Fellow of the American Association for Advancement of Science
in 2006, a Member of the American Academy for Arts and Science in 2007,
and a member of the National Academy of Engineering in 2009.
1995, Professor Khosla co-founded Kosan Biosciences, a public
biotechnology company that developed new polyketide antibiotics and was
acquired by Bristol Myers Squibb in 2008. He is also a founder and
Director of Alvine Pharmaceuticals, a company that is developing an
oral enzyme drug discovered in his laboratory for the treatment of
celiac disease, and serves on the Scientific Advisory Boards of three
renewable energy companies – LS9, Joule and Promethegen.