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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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At least 55 records · Page 3
All sourcesNASA NTRSDOE OSTI
NASA NTRS1973

Trace element analysis of coal by neutron activation.

The irradiation, counting, and data reduction scheme is described for an analysis capability of 1000 samples per year. Up to 56 elements are reported on each sample. The precision and accuracy of the method are shown for 25 elements designated as hazardous by the Environmental Protection Agency (EPA). The interference corrections for selenium and ytterbium on mercury and ytterbium on selenium are described. The effect of bromine and antimony on the determination of arsenic is also mentioned. The use of factorial design techniques to evaluate interferences in the determination of mercury, selenium, and arsenic is shown. Some typical trace element results for coal, fly ash, and bottom ash are given.

Sheibley, D. W.↗
NASA NTRSDate not supplied

Solid-state Architecture Batteries for Enhanced Rechargeability and Safety (SABERS) for Extended Deep Space Applications

Extended duration deep space missions as well as permanent space habitats face numerous technical challenges, key among them is energy generation and energy storage. There are considerable monetary and technical barriers to the generation of power in space. Therefore, it is important to store and be able to access power in an efficient and safe manner over a large number of cycles. Energy storage and in particular, batteries, are vital to the operation of next-generation extraterrestrial shuttles, rovers, habitats and extravehicular activity (EVA) space suits. The performance metrics for extended duration space missions are at least 2 times greater than those set for terrestrial applications such as electric automobiles. Furthermore, safety is essential for operation of space missions particularly involving astronauts such as shuttles, habitats and EVA space suits. Preliminary systems level analysis has indicated that there are five key properties which must be optimized for successful implementation of battery systems. Those five key criteria are: safety, energy density, power, packaging design and scalability. Current state-of-the-art (SOA) lithium-ion batteries can meet or exceed the requirements for certain space applications in the areas of power and scalability, yet are insufficient in the key performance criteria of energy, safety and packaging design. The SABERS concept proposes a battery that meets all five key performance criteria through development of a solid-state architecture battery utilizing high capacity sulfur-selenium cathode and lithium metal anode. The combination of sulfur and selenium offers a balanced energy-to-power density ratio, which can be tailored to the specific application by altering the stoichiometric ratios of sulfur to selenium. This hybrid cathode will be developed by implementing NASA patented holey graphene technology as a highly conductive, ultra-lightweight electrode scaffold. A solid-state electrolyte will be used as a safe, non-flammable replacement to the highly flammable liquid organic electrolytes currently used in SOA lithium-ion batteries. This solid-state lithium-sulfur/selenium cell will be designed into a serial stacking configuration to enable dense packaging of the battery cells. The serial stacking configuration is termed a bipolar stack, which has the advantages of reducing overall cell weight, simplifying the interfaced connections for the cell, and minimizing the cooling requirements for the cell. Lastly, optimization of battery components will occur through a robust and rigorous combination of various computational modeling techniques covering multiple length scales. The expected result will be a fully solid-state battery with operational temperatures up to 150 °C which provides the required energy density, discharge rates, and inherent safety to meet the strict space mission performance criteria. In particular, the wide operational temperature window is required for the large temperature ranges which are experienced across a broad range of potential space missions. This presentation will show initial results that demonstrate the SABERS team has developed a composite carbon-sulfur cathode which exceeds 1100 Wh/kg at a discharge rate of 0.4C, and 804 Wh/kg at a discharge rate of 1C. Additionally, this presentation will show the SABERS team multiscale computational modeling approach and has produced a novel particle dynamics method called Solid Electrolyte Sphere Approximation Model (SESAM). SESAM is on the 1-10 µm scale and provides electromechanical and grain interactions for predictive design guidelines for the experimental team to follow.

Urban Air Mobility (UAM) Vehicles↗
NASA NTRSDate not supplied

Solid-state Architecture Batteries for Enhanced Rechargeability and Safety (SABERS) for Electric Aircraft

All-electric vertical take-off and landing vehicles (eVTOL) for urban air mobility (UAM) concepts face numerous challenging technical barriers before their introduction into the consumer marketplace. The primary barrier to overcome is developing an energy storage system capable of meeting the rigorous aerospace safety and performance criteria. The performance metrics for eVTOL vehicles are at least two times greater than those of electric ground vehicles. Furthermore, inherently non-flammable batteries are essential for safe operation of commercial electric aerovehicles. The SABERS concept proposes a battery that meets the key performance criteria through development of a solid-state architecture battery utilizing high-capacity sulfur-selenium cathode and lithium metal anode. The combination of sulfur and selenium offers a balanced energy-to-power density ratio, which can be tailored to the specific application by altering the stoichiometric ratios of sulfur to selenium. This hybrid cathode will be developed by implementing NASA patented holey graphene technology as a highly conductive, ultra-lightweight electrode scaffold. A solid-state electrolyte will be used as a safe, non-flammable replacement to the highly flammable liquid organic electrolytes currently used in SOA lithium-ion batteries. This solid-state lithium-sulfur/selenium cell will be designed into a serial stacking configuration to enable dense packaging of the battery cells. The serial stacking configuration is termed a bipolar stack, which has the advantages of reducing overall cell weight, simplifying the interfaced connections for the cell, and minimizing the cooling requirements. Lastly, optimization of battery components will occur through a robust and rigorous combination of various computational modeling techniques covering multiple length scales. The expected result will be a fully solid-state battery with operational temperatures up to 150 °C which provides the required energy density, discharge rates, and inherent safety to meet the strict aerospace mission performance criteria. This presentation will demonstrate a feasible path for solid-state cells that possess a specific energy of greater than 400 Wh/kg to enable electric aircraft.

Urban Air Mobility (UAM) Vehicles↗
NASA NTRSDate not supplied

Solid-state Architecture Batteries for Enhanced Rechargeability and Safety (SABERS) Beyond Li-Ion: Technology to Enable Sustainable Electric Aviation

All-electric vertical take-off and landing vehicles (eVTOL) for urban air mobility (UAM) concepts face numerous challenging technical barriers before their introduction into the consumer marketplace. The primary barrier to overcome is developing an energy storage system capable of meeting the rigorous aerospace safety and performance criteria. The performance metrics for eVTOL vehicles are at least two times greater than those of electric ground vehicles. Furthermore, inherently non-flammable batteries are essential for safe operation of commercial electric aerovehicles. The SABERS concept proposes a battery that meets the key performance criteria through development of a solid-state architecture battery utilizing high-capacity sulfur-selenium cathode and lithium metal anode. The combination of sulfur and selenium offers a balanced energy-to-power density ratio, which can be tailored to the specific application by altering the stoichiometric ratios of sulfur to selenium. This hybrid cathode will be developed by implementing NASA patented holey graphene technology as a highly conductive, ultra-lightweight electrode scaffold. A solid-state electrolyte will be used as a safe, non-flammable replacement to the highly flammable liquid organic electrolytes currently used in SOA lithium-ion batteries. This solid-state lithium-sulfur/selenium cell will be designed into a serial stacking configuration to enable dense packaging of the battery cells. The serial stacking configuration is termed a bipolar stack, which has the advantages of reducing overall cell weight, simplifying the interfaced connections for the cell, and minimizing the cooling requirements. Lastly, optimization of battery components will occur through a robust and rigorous combination of various computational modeling techniques covering multiple length scales. The expected result will be a fully solid-state battery with operational temperatures up to 150 °C which provides the required energy density, discharge rates, and inherent safety to meet the strict aerospace mission performance criteria. This presentation will demonstrate a feasible path for solid-state cells that possess a specific energy of greater than 400 Wh/kg to enable electric aircraft.

Urban Air Mobility (UAM) Vehicles↗
NASA NTRS2023

Solid-State Architecture Batteries for Enhanced Rechargeability and Safety (SABERS): Advanced Battery Technology for Sustainable Aviation

All-electric vertical take-off and landing vehicles (eVTOL) for urban air mobility (UAM) concepts face numerous challenging technical barriers before their introduction into the consumer marketplace. The primary barrier to overcome is developing an energy storage system capable of meeting the rigorous aerospace safety and performance criteria. The performance metrics for eVTOL vehicles are at least two times greater than those of electric ground vehicles. Furthermore, inherently non-flammable batteries are essential for safe operation of commercial electric aerovehicles. The SABERS concept proposes a battery that meets the key performance criteria through development of a solid-state architecture battery utilizing high-capacity sulfur-selenium cathode and lithium metal anode. The combination of sulfur and selenium offers a balanced energy-to-power density ratio, which can be tailored to the specific application by altering the stoichiometric ratios of sulfur to selenium. This hybrid cathode will be developed by implementing NASA patented holey graphene technology as a highly conductive, ultra-lightweight electrode scaffold. A solid-state electrolyte will be used as a safe, non-flammable replacement to the highly flammable liquid organic electrolytes currently used in SOA lithium-ion batteries. This solid-state lithium-sulfur/selenium cell will be designed into a serial stacking configuration to enable dense packaging of the battery cells. The serial stacking configuration is termed a bipolar stack, which has the advantages of reducing overall cell weight, simplifying the interfaced connections for the cell, and minimizing the cooling requirements. Lastly, optimization of battery components will occur through a robust and rigorous combination of various computational modeling techniques covering multiple length scales. The expected result will be a fully solid-state battery with operational temperatures up to 150 °C which provides the required energy density, discharge rates, and inherent safety to meet the strict aerospace mission performance criteria. This presentation will demonstrate a feasible path for solid-state cells that possess a specific energy of greater than 400 Wh/kg to enable electric aircraft. The presentation will also explore novel materials and computational models used to achieve all solid-state cells that operate safely at very high temperatures and specific energies. The cells can withstand damage while operating without an increase in temperature or spontaneous ignition.

Urban Air Mobility (UAM) Vehicles↗
NASA NTRSDate not supplied

Solid-state Architecture Batteries for Enhanced Rechargeability and Safety (SABERS) Beyond Li-Ion: Technology to Enable Sustainable Electric Aviation

All-electric and hybrid electric aerovehicle concepts face numerous technical barriers prior to their introduction into the consumer marketplace in order to meet sustainable aviation goals. One of the primary barriers to overcome is developing an energy dense storage system capable of meeting the rigorous aerospace safety and performance criteria. Additionally, the electric aviation market requires that the batteries be fabricated in a sustainable manner with materials that are readily available and abundant within the U.S. to ensure there are no supply chain issues during manufacturing. The performance metrics to enable electric aviation are at least two times greater than those of electric ground vehicles. Furthermore, inherently non-flammable batteries are essential for safe operation of commercial electric aerovehicles. The SABERS concept proposes a battery that meets the key performance criteria through development of a solid-state architecture battery utilizing high-capacity sulfur-selenium cathode and lithium metal anode. The combination of sulfur and selenium offers a balanced energy-to-power density ratio, which can be tailored to the specific application by altering the stoichiometric ratios of sulfur to selenium. The hybrid cathode has been developed by implementing NASA patented holey graphene technology as a highly conductive, ultra-lightweight electrode scaffold. A solid-state electrolyte has been used as a safe, non-flammable replacement to the highly flammable liquid organic electrolytes currently used in SOA lithium-ion batteries. This solid-state lithium-sulfur/selenium cell will be designed into a serial stacking configuration to enable dense packaging of the battery cells. The serial stacking configuration is termed a bipolar stack, which has the advantages of reducing overall cell weight, simplifying the interfaced connections for the cell, and minimizing the cooling requirements. Lastly, optimization of battery components will occur through a robust and rigorous combination of various computational modeling techniques covering multiple length scales. The expected result will be a fully solid-state battery with operational temperatures up to 150 °C which provides the required energy density, discharge rates, and inherent safety to meet the strict aerospace mission performance criteria. This poster summarizes recent results from battery component optimization to scale-up production of full SABERS pouch cells.

Urban Air Mobility (UAM) Vehicles↗
NASA NTRSDate not supplied

Solid-State Architecture Batteries for Enhanced Rechargeability and Safety (SABERS) Beyond Li-Ion: Technology to Enable Next-Generation Sustainable Electric

All-electric vertical take-off and landing vehicles (eVTOL) for urban air mobility (UAM) concepts face numerous challenging technical barriers before their introduction into the consumer marketplace. The primary barrier to overcome is developing an energy storage system that meets rigorous aerospace safety and performance criteria. The performance metrics for eVTOL vehicles are at least two times greater than those of electric ground vehicles. Furthermore, inherently non-flammable batteries are essential for the safe operation of commercial electric aero vehicles. The SABERS concept proposes a battery that meets the critical performance criteria by developing a solid-state architecture battery utilizing a high-capacity sulfur-selenium cathode and lithium metal anode. The combination of sulfur and selenium offers a balanced energy-to-power density ratio, which can be tailored to the specific application by altering the stoichiometric ratios of sulfur to selenium. This hybrid cathode will be developed using NASA-patented holey graphene technology as a highly conductive, ultra-lightweight electrode scaffold. A solid-state electrolyte will be used as a safe, non-flammable replacement for the highly flammable liquid organic electrolytes currently in SOA lithium-ion batteries. This solid-state lithium-sulfur/selenium cell will be designed in a serial stacking configuration to enable the dense packaging of the battery cells. The serial stacking configuration is termed a bipolar stack, which has the advantages of reducing overall cell weight, simplifying the interfaced connections for the cell, and minimizing the cooling requirements. Lastly, the optimization of battery components will occur through a robust and rigorous combination of various computational modeling techniques covering multiple length scales. The expected result will be a fully solid-state battery with operational temperatures up to 150°C, providing the required energy density, discharge rates, and inherent safety to meet the strict aerospace mission performance criteria. The SABERS team employed novel materials development, computational modeling, and design-of-experiments (DOE) optimization studies in their research. This presentation will show the results of these studies and demonstrate a feasible path for solid-state cells with a specific energy greater than 400 Wh/kg to enable electric aircraft.

Computational Modeling↗
NASA NTRS1974

Containerless processing of single crystals in low-G environment

Experiments on containerless crystal growth from the melt were conducted during Skylab missions SL3 and SL4 (Skylab Experiment M-560). Six samples of InSb were processed, one of them heavily doped with selenium. The concept of the experiment is discussed and related to general crystal growth methods and their merits as techniques for containerless processing in space. The morphology of the crystals obtained is explained in terms of volume changes associated with solidification and wetting conditions during solidification. All samples exhibit extremely well developed growth facets. Analysis by X-ray topographical methods and chemical etching shows that the crystals are of high structural perfection. Average dislocation density as revealed by etching is of the order of 100 per sq cm; no dislocation clusters could be observed in the space-grown samples. A sequence of striations that is observed in the first half of the selenium-doped sample is explained as being caused by periodic surface breakdown.

Walter, H. U.↗
NASA NTRS1983

El Chichon - Composition of plume gases and particles

Aircraft measurements were made of trace gases, atmospheric particles, and condensed acid volatiles in the plume of El Chichon volcano, Chiapas, Mexico, in November 1982. Hydrogen sulfide was the primary gaseous sulfur species in the plume at the time of collection. Concentrations of 28 elements were determined by neutron activation analysis of particulate material from the plume. The volatile elements sulfur, chlorine, arsenic, selenium, bromine, antimony, iodine, tungsten, and mercury were enriched relative to bulk pyroclastic material by factors of 60 to 20,000. Arsenic, antimony, and selenium were associated predominantly with small (not greater than 3 micrometer) particles. Calcium and sodium were present almost exclusively on larger particles and aluminum and manganese were bimodally distributed. Ashladen particulate material injected into the stratosphere during the early violent eruptions was enriched by factors of 10 to 30 relative to ash in some of the same elements observed in the quiescent plume.

Kotra, J. P.↗
NASA NTRS1985

Evidence for gain on the C VI 182 A transition in a radiation-cooled selenium/Formvar plasma

Thin plastic foils coated with selenium have been irradiated using from 4 to 8 beams of the OMEGA laser in a line focus configuration. Spectra were recorded using a 3 meter spectrograph that viewed the plasma along the line focus. Based on a comparison of the intensities of the spectral lines from plasmas with lengths of 1.7, 3.4, 6.8, and 13.6 mm, the C VI n = 3 to 2 transition at 182 A was anomalously intense in the spectra from the longer plasmas. Calculations indicate that the carbon plasma was cooled by radiation from the highly-charged selenium plasma in a time that was smaller than the expansion time of the plasma. These plasma conditions are favorable for the occurrence of population inversions between the n = 2 and 3 levels of C VI resulting from recombination and cascading from higher levels. The measured gain coefficient for the C VI 182 A transition is 3/cm, and this corresponds to a gain-length product of 4 in the longest plasma.

Seely, J. F.↗
NASA NTRS1990

Interface demarcation in GaAs by current pulsing

GTE Laboratories is currently conducting a program to investigate the effect of convection in the melt on the properties of bulk grown gallium arsenide (GaAs). In addition to extensive ground based experimentation, a Get Away Special growth system has been developed to grow two GaAs crystals aboard the Space Shuttle, each with a one inch diameter. In order to perform a complete segregation analysis of the crystals grown in space, it is necessary to measure the interface shape and growth rate as well as the spatial distribution of the selenium dopant. The techniques for interface demarcation in selenium doped GaAs by current pulsing have been developed at GTE Laboratories and successful interface demarcation has been achieved for current pulses ranging from 20 to 90 amps, in both single crystal and polycrystalline regions.

Matthiesen, D. H.↗
NASA NTRS1994

The study of dopant segregation behavior during the growth of GaAs in microgravity

An investigation into the segregation behavior of selenium doped gallium arsenide during directional solidification in the microgravity environment was conducted using the Crystal Growth Furnace (CGF) aboard the first United States Microgravity Laboratory (USML-1). The two crystals grown were 1.5 cm in diameter and 16.5 cm in length with an initial melt length of 14 cm. Two translation periods were executed, the first at 2.5 microns/s and after a specified time, which was different between the two experiments, the translation rate was doubled to 5.0 microns/s. The translation was then stopped and the remaining sample melt was solidified using a gradient freeze technique in the first sample and a rapid solidification in the second experiment. Measurement of the selenium dopant distribution, using quantitative infrared transmission imaging, indicates that the first sample initially achieved diffusion controlled growth as desired. However, after about 1 cm of growth, the segregation behavior was driven from a diffusion controlled growth regime to a complete mixing regime. Measurements in the second flight sample indicated that the growth was always in a complete mixing regime. In both experiments, voids in the center line of the crystal, indicative of bubble entrapment, were found to correlate with the position in the crystal when the translation rates were doubled.

Matthiesen, David H.↗
NASA NTRS1997

Comparison of OARE Accelerometer Data with Dopant Distribution in Se-Doped GaAs Crystals Grown During USML-1

Experiments were conducted in the crystal growth furnace (CGF) during the first United States Microgravity Laboratory (USML-1), the STS-50 flight of the Space Shuttle Columbia, to determine the segregation behavior of selenium in bulk GaAs in a microgravity environment. After the flight, the selenium-doped GaAs crystals were sectioned, polished, and analyzed to determine the free carrier concentration as a function of position, One of the two crystals initially exhibited an axial concentration profile indicative of diffusion controlled growth, but this profile then changed to that predicted for a complete mixing type growth. An analytical model, proposed by Naumann [R.J. Naumann, J. Crystal Growth 142 (1994) 253], was utilized to predict the maximum allowable microgravity disturbances transverse to the growth direction during the two different translation rates used for each of the experiments. The predicted allowable acceleration levels were 4.86 microgram for the 2.5 micrometers/s furnace translation rate and 38.9 microgram for the 5.0 micrometers/s rate. These predicted values were compared to the Orbital Acceleration Research Experiment (OARE) accelerometer data recorded during the crystal growth periods for these experiments. Based on the analysis of the OARE acceleration data and utilizing the predictions from the analytical model, it is concluded that the change in segregation behavior was not caused by any acceleration events in the microgravity environment.

Moskowitz, Milton E.↗
NASA NTRS2017

Functionalized Media and Methods of Making and Using Therefor

Methods, compositions, devices and kits are provided herein for separating, scavenging, capturing or identifying a metal from a target using a medium or scaffold with a selenium-containing functional group. The medium or the scaffold including the selenium-containing functional group has affinity and specificity to metal ions or compounds having one or more metals, and efficiently separates, recovers, and scavenges of the metals from a target such as a sample, solution, suspension, or mixture.

Huang, Yongsong↗