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Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.

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All sourcesNASA NTRSDOE OSTI
DOE OSTI2025

Designing Moderately‐Solvating Electrolytes for High‐Performance Lithium–Sulfur Batteries

New electrolytes are critical for high‐energy lithium (Li)–sulfur (S) batteries (LSBs) to ensure their stability against Li metal anode and polysulfides (PSs) shuttling which hinder the large‐scale application of LSBs. In this study, the design principle of moderately solvating electrolytes (MSEs) for LSBs is demonstrated by using a multiple‐solvent system comprising of a highly solvating solvent, a weakly solvating solvent, and a non‐solvating solvent to create a well‐balanced electrolyte system. This resulting electrolyte significantly improves the cycle life of LSBs, achieving 300 cycles, which is twice as long as that of similar cells with the conventional electrolyte and it also ensures stable calendar life for at least seven months. The optimal MSE forms robust passivation layers enhancing the structural integrity of both S and Li metal electrodes after cycling. These virtues effectively hinder parasitic side reactions and self‐discharge behavior of LSBs. This electrolyte design principle is versatile and can be applied to other battery chemistries, providing a potential path toward the development of a more efficient and stable battery system. By addressing key challenges such as the instability of electrodes and shuttling of polysulfides, this electrolyte approach offers promising solutions for advancing LSB technology.

25 ENERGY STORAGE↗
DOE OSTI2025

The Origin of Improved Performance in Boron‐Alloyed Silicon Nanoparticle‐Based Anodes for Lithium‐Ion Batteries

Stabilizing the solid electrolyte interphase (SEI) remains a key challenge for silicon‐based lithium‐ion battery anodes. Alloying silicon with secondary elements like boron has emerged as a promising strategy to improve the cycle life of silicon anodes, yet the underlying mechanism remains unclear. To address this knowledge gap, how boron concentration influences battery performance is systematically investigated. These results show a near‐monotonic increase in cycle lifetime with higher boron content, with boron‐rich electrodes significantly outperforming pure silicon. Additionally, silicon‐boron alloy anodes exhibit nearly three times longer calendar life than pure silicon. Through detailed mechanistic analysis, alternative contributing factors are systematically ruled out, and it is proposed that improved passivation arises from a strong permanent dipole at the nanoparticle surface. This dipole, formed by undercoordinated and highly Lewis acidic boron, creates a static, ion‐dense layer that stabilizes the electrochemical interface, reducing parasitic electrolyte decomposition and enhancing long‐term stability. These findings suggest that, within the SEI framework, the electric double layer is an important consideration in surface passivation. This insight provides an underexplored parameter space for optimizing silicon anodes in next‐generation lithium‐ion batteries.

25 ENERGY STORAGE↗
DOE OSTI2021

Early Battery Performance Prediction for Mixed Use Charging Profiles Using Hierarchal Machine Learning

A key step limiting how fast batteries can be deployed is the time necessary to provide evaluation and validation of performance. Using data analysis approaches, such as machine learning, the validation process can be accelerated. However, questions on the validity of projecting models trained on limited data or simple cycling profiles, such as constant current cycling, to real-world scenarios with complex loads remains. Here, we present the ability to predict performance with less than 1.2% mean absolute percent error when trained on cells aged using complex electric vehicle discharge profiles, and either AC Level 2 charge or DC Fast charge profiles, using only the first 45 cycles, namely 5% of the total testing time. While error is low across the projections, this study also highlights that battery lifetime analysis using only cycling data may not extrapolate safely to certain real-world conditions due to the impact of calendar degradation.

25 ENERGY STORAGE↗
DOE OSTI2023

Degradation and Modeling of Large-Format Commercial Lithium-Ion Cells as a Function of Chemistry, Design, and Aging Conditions

Demand for large-format (>10 Ah) lithium-ion batteries has increased substantially in recent years, due to the growth of both electric vehicle and stationary energy storage markets. The economics of these applications is sensitive to the lifetime of the batteries, and end-of-life can either be due to energy or power limitations. Despite this, there is little information from cell manufacturers on the sensitivity of cell degradation to environmental conditions or battery use. This work reports accelerated aging test data from four commercial large-format lithium-ion batteries from three manufacturers, with varying design (thickness, casings, ...), chemistry (lithium-iron-phosphate (LFP) or lithium-nickel-manganese-cobalt-oxide positive electrodes (NMC), with graphite (Gr) negative electrodes), and capacity (50 to 250 Amp hours). The tested LFP|Gr cell is found to be relatively insensitive to cycling conditions like temperature or voltage window, while NMC|Gr cells have varying sensitivity. Degradation trends are further investigated by training predictive models: simple polynomial trend lines, a semi-empirical reduced-order model, and an empirical reduced-order model identified using machine-learning based on symbolic regression. Calendar and cycle life are simulated over a variety of conditions to directly compare the various batteries. Cell size and thickness are found to substantially impact sensitivity to temperature during cycle aging, while electrode chemistry impacts depth-of-discharge sensitivity. Real-world battery lifetime is evaluated by simulating residential energy storage and commercial frequency containment reserve systems in several U.S. climate regions. Predicted lifetime across cell types varies from 7 years to 20+ years, though all cells are predicted to have at least 10 year life in certain conditions.

battery lifetime↗
DOE OSTI2022

Role of Coatings as Artificial Solid Electrolyte Interphases on Lithium Metal Self-Discharge

Artificial solid electrolyte interphases have provided a path to improved cycle life for high energy density, next-generation anodes like lithium metal. Although long cycle life is necessary for widespread implementation, understanding and mitigating the effects of aging and self-discharge are also required. In this report we investigate several coating materials and their role in calendar life aging of lithium. We find that the oxide coatings are electronically passivating whereas the LiF coating slows charge transfer kinetics. Furthermore, the Coulombic loss during self-discharge measurements improves with the oxide layers and worsens with the LiF layer. It is found that none of the coatings create a continuous conformal, electronically passivating layer on top of the deposited lithium nor are they likely to distribute evenly through a porous deposit, suggesting that none of the materials are acting as an artificial solid electrolyte interphase. Instead, they likely alter performance through modulating lithium nucleation and growth.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗
DOE OSTI2026

4D-STEM Coupled with Unsupervised Machine Learning to Reveal at Large-Scale the Microstructural Evolution in Li- and Mn-Rich Cathodes

Li- and Mn-rich (LMR) layered oxides are known to exhibit a thin surface reconstruction layer, which grows during electrochemical cycling in a manner that depends on exposed crystallographic facets, cycling conditions, and electrolyte chemistry. Direct characterization of this layer has traditionally relied on high-resolution electron microscopy, which is inherently limited to small fields of view. Here, we employ four-dimensional scanning transmission electron microscopy (4D-STEM) combined with unsupervised machine-learning clustering to quantitatively map phase distributions over large areas and track their evolution in LMR cathodes during electrochemical aging. Our results show that the surface reconstruction layer consists predominantly of a rocksalt phase, whose thickness varies across different facets following activation cycling and becomes substantially thicker and more uniform during calendar aging. In contrast, a spinel-like phase is observed within the particle bulk. Large-area phase mapping and correlative high-resolution imaging reveal that this spinel-like phase preferentially nucleates at bulk crystallographic defects, including boundaries between 60°-rotated layered domains and associated mixed-phase regions, rather than exclusively at the particle surface. Our findings establish a mechanistic distinction between surface-driven rocksalt formation and bulk-defect-mediated spinel nucleation while demonstrating the unique capability of 4D-STEM to provide statistically robust, mesoscale insight into complex phase-evolution processes in LMR cathodes.

4D-STEM↗
DOE OSTI2011

Set of Comparable Carbon Footprints for Highway Travel in Metropolitan America

The authors describe the development of a set of carbon dioxide emissions estimates for highway travel by automobile, truck, bus and other public transit vehicle movements within the nation s 100 largest metropolitan areas, in calendar year 2005. Considerable variability is found to exist across metropolitan areas when these greenhouse gas emissions are measured on a per capita and a per gross metropolitan product (GMP) basis. Least square regression modeling shows a relationship between emissions per capita and per GMP with truck traffic share, transit share, employment density, population dispersion within the metro area, and GMP per capita. As a result many of the nation s largest metropolitan areas tend to have lower CO2 emissions per capita and per GMP than smaller and more recently developed metro areas.

54 ENVIRONMENTAL SCIENCES↗
DOE OSTI2022

Determinants of residential mobility: an adaptive retrospective survey method

This study introduces a survey instrument to collect retrospective life-course events, focusing on residential relocation, and it utilizes the survey to evaluate determinants of residential mobility. Here, the survey consists of seven modules collecting information about household structure and household demographics, latest residential relocation, current and previous home, employment, education, vehicle ownership, and travel behavior. The time window of the life-course calendar in the survey is customized according to the latest residential relocation as an anchor point to assist with memory recollection and balance the required input from participants. The survey is used to collect data from a sample of 514 respondents in Sydney, Australia, and another sample of 404 respondents in Chicago, Illinois, in the US. The Cox proportional hazard model is used to analyze residential mobility. The results show primary school commencement is a salient determinant of residential relocation, but its impact is significantly higher in Chicago compared to Sydney.

96 KNOWLEDGE MANAGEMENT AND PRESERVATION↗
DOE OSTI2013

DID THE ANCIENT EGYPTIANS RECORD THE PERIOD OF THE ECLIPSING BINARY ALGOL-THE RAGING ONE?

The eclipses in binary stars give precise information of orbital period changes. Goodricke discovered the 2.867 day period in the eclipses of Algol in the year 1783. The irregular orbital period changes of this longest known eclipsing binary continue to puzzle astronomers. The mass transfer between the two members of this binary should cause a long-term increase of the orbital period, but observations over two centuries have not confirmed this effect. Here, we present evidence indicating that the period of Algol was 2.850 days three millennia ago. For religious reasons, the ancient Egyptians have recorded this period into the Cairo Calendar (CC), which describes the repetitive changes of the Raging one. CC may be the oldest preserved historical document of the discovery of a variable star.

79 ASTRONOMY AND ASTROPHYSICS↗
DOE OSTI2021

Challenging Practices of Algebraic Battery Life Models through Statistical Validation and Model Identification via Machine-Learning

Various modeling techniques are used to predict the capacity fade of Li-ion batteries. Algebraic reduced-order models, which are inherently interpretable and computationally fast, are ideal for use in battery controllers, technoeconomic models, and multi-objective optimizations. For Li-ion batteries with graphite anodes, solid-electrolyte-interphase (SEI) growth on the graphite surface dominates fade. This fade is often modeled using physically informed equations, such as square-root of time for predicting solvent-diffusion limited SEI growth, and Arrhenius and Tafel-like equations predicting the temperature and state-of-charge rate dependencies. In some cases, completely empirical relationships are proposed. However, statistical validation is rarely conducted to evaluate model optimality, and only a handful of possible models are usually investigated. This article demonstrates a novel procedure for automatically identifying reduced-order degradation models from millions of algorithmically generated equations via bi-level optimization and symbolic regression. Identified models are statistically validated using cross-validation, sensitivity analysis, and uncertainty quantification via bootstrapping. On a LiFePO 4 /Graphite cell calendar aging data set, automatically identified models utilizing square-root, power law, stretched exponential, and sigmoidal functions result in greater accuracy and lower uncertainty than models identified by human experts, and demonstrate that previously known physical relationships can be empirically "rediscovered" using machine learning.

25 ENERGY STORAGE↗
DOE OSTI2010

Development of tools and techniques for momentum compression of fast rare isotopes

As part of our past research and development work, we have created and developed the LISE++ simulation code [Tar04, Tar08]. The LISE++ package was significantly extended with the addition of a Monte Carlo option that includes an option for calculating ion trajectories using a Taylor-series expansion up to fifth order, and implementation of the MOTER Monte Carlo code [Kow87] for ray tracing of the ions into the suite of LISE++ codes. The MOTER code was rewritten from FORTRAN into C++ and transported to the MS-Windows operating system. Extensive work went into the creation of a user-friendly interface for the code. An example of the graphical user interface created for the MOTER code is shown in the left panel of Figure 1 and the results of a typical calculation for the trajectories of particles that pass through the A1900 fragment separator are shown in the right panel. The MOTER code is presently included as part of the LISE++ package for downloading without restriction by the worldwide community. The LISE++ was extensively developed and generalized to apply to any projectile fragment separator during the early phase of this grant. In addition to the inclusion of the MOTER code, other important additions to the LISE++ code made during FY08/FY09 are listed. The LISE++ is distributed over the web (http://groups.nscl.msu.edu/lise ) and is available without charge to anyone by anonymous download, thus, the number of individual users is not recorded. The number of 'hits' on the servers that provide the LISE++ code is shown in Figure 3 for the last eight calendar years (left panel) along with the country from the IP address (right panel). The data show an increase in web-activity with the release of the new version of the program during the grant period and a worldwide impact. An important part of the proposed work carried out during FY07, FY08 and FY09 by a graduate student in the MSU Physics program was to benchmark the codes by comparison of detailed measurements to the LISE++ predictions. A large data set was obtained for fission fragments from the reaction of 238U ions at 81 MeV/u in a 92 mg/cm2 beryllium target with the A1900 projectile fragment separator. The data were analyzed and form the bulk of a Ph.D. dissertation that is nearing completion. The rich data set provides a number of benchmarks for the improved LISE++ code and only a few examples can be shown here. The primary information obtained from the measurements is the yield of the products as a function of mass, charge and momentum. Examples of the momentum distributions of individually identified fragments can be seen in Figures 2 and 4 along with comparisons to the predicted distributions. The agreement is remarkably good and indicates the general validity of the model of the nuclear reactions producing these fragments and of the higher order transmission calculations in the LISE++ code. The momentum distributions were integrated to provide the cross sections for the individual isotopes. As shown in Figure 5, there is good agreement with the model predictions although the observed cross sections are a factor of five or so higher in this case. Other comparisons of measured production cross sections from abrasion-fission reactions have been published by our group working at the NSCL during this period [Fol09] and through our collaboration with Japanese researchers working at RIKEN with the BigRIPS separator [Ohn08, Ohn10]. The agreement of the model predictions with the data obtained with two different fragment separators is very good and indicates the usefulness of the new LISE++ code.

46 INSTRUMENTATION RELATED TO NUCLEAR SCIENCE AND ↗
DOE OSTI2010

Powertrain Component Inspection from Mid-Level Blends Vehicle Aging Study

The Energy Independence and Security Act of 2007 calls on the nation to significantly increase its use of renewable fuels to meet its transportation energy needs. The law expands the renewable fuel standard to require use of 36 billion gallons of renewable fuel by 2022. Given that ethanol is the most widely used renewable fuel in the U.S. market, ethanol will likely make up a significant portion of the 36-billion-gallon requirement. The vast majority of ethanol used in the United States is blended with gasoline to create E10-gasoline with up to 10% ethanol. The remaining ethanol is sold in the form of E85 - a gasoline blend with as much as 85% ethanol that can only be used in flexible-fuel vehicles (FFVs). Consumption of E85 is at present limited by both the size of the FFV fleet and the number of E85 fueling stations. Gasoline consumption in the United States is currently about 140 billion gallons per year; thus the maximum use of ethanol as E10 is only about 14 billion gallons. While the U.S. Department of Energy (DOE) remains committed to expanding the E85 infrastructure, that market represented less than 1% of the ethanol consumed in 2010 and will not be able to absorb projected volumes of ethanol in the near term. Because of these factors, DOE and others have been assessing the viability of using mid-level ethanol blends (E15 or E20) as a way to accommodate growing volumes of ethanol. The DOE Mid-Level Ethanol Blends Test Program has been under way since 2007, supported jointly by the Office of the Biomass Program and the Vehicle Technologies Program. One of the larger projects, the Catalyst Durability Study, or Vehicle Aging Study, will be completed early in calendar year 2011. The following report describes a subproject of the Vehicle Aging Study in which powertrain components from 18 of the vehicles were examined at Southwest Research Institute under contract to Oak Ridge National Laboratory (ORNL).

02 PETROLEUM↗
DOE OSTI2010

Trends in U.S. Venture Capital Investments Related to Energy: 1980 through the Second Quarter of 2010

This report documents trends in U.S. venture capital investments over the period 1980 through the second quarter of calendar year 2010 (2010Q1+Q2). Particular attention is given to U.S. venture capital investments in the energy/industrial sector over the period 1980-2010Q1+Q2 as well as in the more recently created cross-cutting category of CleanTech over the period 1995-2010Q1+Q2. During the early 1980s, U.S. venture capital investments in the energy/industrial sector accounted for more than 20% of all venture capital investments. However subsequent periods of low energy prices, the deregulation of large aspects of the energy industry, and the emergence of fast growing new industries like computers (both hardware and software), biotechnology and the Internet quickly reduced the priority accorded to energy/industrial investments. To wit, venture capital investments related to the energy/industrial sector accounted for only 1% of the $119 billion dollars invested in 2000 by the U.S. venture capital community. The significant increase in the real price of oil that began in 2003-2004 correlates with renewed interest and increased investment by the venture capital community in energy/industrial investment opportunities. Venture capital investments for 2009 for the energy/industrial sector accounted for $2.1 billion or slightly more than 13% of all venture capital invested that year. The total venture capital invested in energy/industrial during the first two quarters of 2010 is close to $1.8 billion accounting for 17% of all venture capital investments during the first two quarters of 2010. In 2009, the aggregate amount invested in CleanTech was $1.8 billion (30% of the total US venture capital invested in that lean year) and for the first two quarters of 2010 US venture capital investments in CleanTech have already exceeded $1.9 billion (19% of all US venture capital investments made during the first half of 2010). Between 2004 and 2009, U.S. venture capital investments in energy/industrial as well as CleanTech have more than quadrupled in real terms.

32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATI↗
DOE OSTI2011

Sandia National Laboratories, California Pollution Prevention Program annual report.

The annual program report provides detailed information about all aspects of the SNL/CA Pollution Prevention Program for a given calendar year. It functions as supporting documentation to the SNL/CA Environmental Management System Program Manual. The program report describes the activities undertaken during the past year, and activities planned in future years to implement the Pollution Prevention Program, one of six programs that supports environmental management at SNL/CA. Pollution Prevention supports the goals and objectives to increase the procurement and use of environmentally friendly products and materials and minimize the generation of waste (nonhazardous, hazardous, radiological, wastewater). Through participation on the Interdisciplinary Team P2 provides guidance for integration of environmentally friendly purchasing and waste minimization requirements into projects during the planning phase. Table 7 presents SNL's corporate objectives and targets that support the elements of the Pollution Prevention program.

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗
DOE OSTI2011

The Argonne Leadership Computing Facility 2010 annual report.

Researchers found more ways than ever to conduct transformative science at the Argonne Leadership Computing Facility (ALCF) in 2010. Both familiar initiatives and innovative new programs at the ALCF are now serving a growing, global user community with a wide range of computing needs. The Department of Energy's (DOE) INCITE Program remained vital in providing scientists with major allocations of leadership-class computing resources at the ALCF. For calendar year 2011, 35 projects were awarded 732 million supercomputer processor-hours for computationally intensive, large-scale research projects with the potential to significantly advance key areas in science and engineering. Argonne also continued to provide Director's Discretionary allocations - 'start up' awards - for potential future INCITE projects. And DOE's new ASCR Leadership Computing (ALCC) Program allocated resources to 10 ALCF projects, with an emphasis on high-risk, high-payoff simulations directly related to the Department's energy mission, national emergencies, or for broadening the research community capable of using leadership computing resources. While delivering more science today, we've also been laying a solid foundation for high performance computing in the future. After a successful DOE Lehman review, a contract was signed to deliver Mira, the next-generation Blue Gene/Q system, to the ALCF in 2012. The ALCF is working with the 16 projects that were selected for the Early Science Program (ESP) to enable them to be productive as soon as Mira is operational. Preproduction access to Mira will enable ESP projects to adapt their codes to its architecture and collaborate with ALCF staff in shaking down the new system. We expect the 10-petaflops system to stoke economic growth and improve U.S. competitiveness in key areas such as advancing clean energy and addressing global climate change. Ultimately, we envision Mira as a stepping-stone to exascale-class computers that will be faster than petascale-class computers by a factor of a thousand. Pete Beckman, who served as the ALCF's Director for the past few years, has been named director of the newly created Exascale Technology and Computing Institute (ETCi). The institute will focus on developing exascale computing to extend scientific discovery and solve critical science and engineering problems. Just as Pete's leadership propelled the ALCF to great success, we know that that ETCi will benefit immensely from his expertise and experience. Without question, the future of supercomputing is certainly in good hands. I would like to thank Pete for all his effort over the past two years, during which he oversaw the establishing of ALCF2, the deployment of the Magellan project, increases in utilization, availability, and number of projects using ALCF1. He managed the rapid growth of ALCF staff and made the facility what it is today. All the staff and users are better for Pete's efforts.

54 ENVIRONMENTAL SCIENCES↗
DOE OSTI2011

SALTSTONE 4QCY10 TCLP RESULTS

Saltstone waste form was prepared in the Savannah River National Laboratory (SRNL) from a Tank 50H sample and Z-Area premix material for the fourth quarter of calendar year 2010 (4QCY10). After the prescribed 28 day cure, samples of the saltstone were collected, and the waste form was shown to meet the South Carolina Hazardous Waste Management Regulations (SCHWMR) R.61-79.261.24 and R.61-79.268.48(a) requirements for a nonhazardous waste form with respect to RCRA metals and underlying hazardous constituents. These analyses met all quality assurance specifications of USEPA SW-846.

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗
DOE OSTI2011

Surveillance of Site A and Plot M report for 2010.

The results of the environmental surveillance program conducted at Site A/Plot M in the Palos Forest Preserve area for Calendar Year 2010 are presented. Based on the results of the 1976-1978 radiological characterization of the site, a determination was made that a surveillance program be established. The characterization study determined that very low levels of hydrogen-3 (as tritiated water) had migrated from the burial ground and were present in two nearby hand-pumped picnic wells. The current surveillance program began in 1980 and consists of sample collection and analysis of surface and subsurface water. The results of the analyses are used to monitor the migration pathway of hydrogen-3 contaminated water from the burial ground (Plot M) to the hand-pumped picnic wells and monitor for the presence of radioactive materials in the environment of the area. Hydrogen-3 in the Red Gate Woods picnic wells was still detected this year, but the average and maximum concentrations were significantly less than found earlier. Hydrogen-3 continues to be detected in a number of wells, boreholes, dolomite holes, and a surface stream. Analyses since 1984 have indicated the presence of low levels of strontium-90 in water from a number of boreholes next to Plot M. The results of the surveillance program continue to indicate that the radioactivity remaining at Site A/Plot M does not endanger the health or safety of the public visiting the site, using the picnic area, or living in the vicinity.

54 ENVIRONMENTAL SCIENCES↗