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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 181 records · Page 10
All sourcesNASA NTRSDOE OSTI
NASA NTRS2010

Supercapacitor Electrolyte Solvents with Liquid Range Below -80 C

A previous NASA Tech Brief ["Low-Temperature Supercapacitors" (NPO-44386) NASA Tech Briefs, Vol. 32, No 7 (July 2008), page 32] detailed ongoing efforts to develop non-aqueous supercapacitor electrolytes capable of supporting operation at temperatures below commercially available cells (which are typically limited to charging and discharging at > or equal to -40 C). These electrolyte systems may enable energy storage and power delivery for systems operating in extreme environments, such as those encountered in the Polar regions on Earth or in the exploration of space. Supercapacitors using these electrolytes may also offer improved power delivery performance at moderately low temperatures (e.g. -40 to 0 C) relative to currently available cells, offering improved cold-cranking and cold-weather acceleration capabilities for electrical or hybrid vehicles. Supercapacitors store charge at the electrochemical double-layer, formed at the interface between a high surface area electrode material and a liquid electrolyte. The current approach to extending the low-temperature limit of the electrolyte focuses on using binary solvent systems comprising a high-dielectric-constant component (such as acetonitrile) in conjunction with a low-melting-point co-solvent (such as organic formates, esters, and ethers) to depress the freezing point of the system, while maintaining sufficient solubility of the salt. Recent efforts in this area have led to the identification of an electrolyte solvent formulation with a freezing point of -85.7 C, which is achieved by using a 1:1 by volume ratio of acetonitrile to 1,3-dioxolane

Brandon, Erik↗
NASA NTRS1973

The electrostatic storage tube

An electrostatic camera system is discussed which is based on the electrostatic storage tube. The development of the system was begun following a series of experiments which indicated that the device offers signficantly improved performance over currently available devices. The approach used in developing the high performance camera involves: converting the input image to an electron image at low loss, applying a low noise gain process, and storing the resulting charge pattern in a low-loss target. The basic processes and elements of the electrostatic storage tube are illustrated and discussed. Graphs that depict the camera performance characteristics are included.

Rutherford, R. E., Jr.↗
NASA NTRS1994

Performance test results of ETS-6 Ni-Cd cells

The topics covered are presented in viewgraph form and include the following: development schedule; main specification; cell design; production flow; acceptance test (1); acceptance test (2); cell weight; 20 C performance; capacity; overcharge pressure; end of charge voltage; -5 C performance; ETS-VI simulation cycle test; and battery storage.

Nakatani, Kensuke↗
NASA NTRS1995

Nickel metal hydride LEO cycle testing

The George C. Marshall Space Flight Center is working to characterize aerospace AB5 Nickel Metal Hydride (NiMH) cells. The cells are being evaluated in terms of storage, low earth orbit (LEO) cycling, and response to parametric testing (high rate charge and discharge, charge retention, pulse current ability, etc.). Cells manufactured by Eagle Picher are the subjects of the evaluation. There is speculation that NiMH cells may become direct replacements for current Nickel Cadmium cells in the near future.

Lowery, Eric↗
NASA NTRS2009

Performance Testing of Yardney Li-Ion Cells and Batteries in Support of Future NASA Missions

NASA requires lightweight rechargeable batteries for future missions to Mars and the outer planets that are capable of operating over a wide range of temperatures, with high specific energy and energy densities. Due to the attractive performance characteristics, Li-ion batteries have been identified as the battery chemistry of choice for a number of future applications. For example, JPL is planning to launch another unmanned rover mission to the planet Mars. This mission, referred to as the Mars Science Laboratory (MSL), will involve the use of a rover that is much larger than the previously developed Spirit and Opportunity Rovers for the 2003 Mars Exploration Rover (MER) mission, that are currently still in operation on the surface of the planet after more than five years. Part of the reason that the MER rovers have operated so successfully, far exceeding the required mission duration of 90 sols, is that they possess robust Li-ion batteries, manufactured by Yardney Technical Products, which have demonstrated excellent life characteristics. Given the excellent performance characteristics displayed, similar Li-ion batteries have been projected to successfully meet the mission requirements of the up-coming MSL mission. In addition to future missions to Mars, Li-ion technology is attractive for a number of other future NASA applications which require high specific energy, rechargeable batteries. To ascertain the viability of using Li-ion batteries for these applications, a number of performance validation tests have been performed on both Yardney cells and batteries of various sizes. These tests include mission simulation tests, charge and discharge rate characterization testing, cycle life testing under various conditions, and storage testing.

Smart, M. C.↗
NASA NTRS2008

What Might We Learn About Magnetospheric Substorms at the Earth from the MESSENGER Measurements at Mercury?

Satellite observations at the Earth, supported by theory and modeling, have established a close connection between the episodes of intense magnetospheric convection termed substorms and the occurrence of magnetic reconnection. Magnetic reconnection at the dayside magnetopause results in strong energy input to the magnetosphere. This energy can either be stored or used immediately to power the magnetospheric convection that produces the phenomena that collectively define the 'substorm.' However, many aspects of magnetic reconnection and the dynamic response of the coupled solar wind - magnetosphere - ionosphere system at the Earth during substorms remain poorly understood. For example, the rate of magnetic reconnection is thought to be proportional to the local Alfven speed, but the limited range of changes in this solar wind parameter at 1 AU have made it difficult to detect its influence over energy input to the Earth's magnetosphere. In addition, the electrical conductance of the ionosphere and how it changes in response to auroral charged particle precipitation are hypothesized to play a critical role in the development of substorms, but the nature of this electrodynamic interaction remain difficult to deduce from Earth observations alone. The amount of energy the terrestrial magnetosphere can store in its tail, the duration of the storage, and the trigger(s) for its dissipation are all thought to be determined by not only the microphysics of the cross-tail current layer, but also the properties of the coupled magnetosphere - ionosphere system. Again, the separation of microphysics effects from system response has proved very difficult using measurements taken only at the Earth. If MESSENGER'S charged particle and magnetic field measurements confirm the occurrence of terrestrial-style substorms in Mercury's miniature magnetosphere, then it may be possible to determine how magnetospheric convection, field-aligned currents, charged particle acceleration, reconnection, and tail energy storage are influenced by the intense magnetic reconnection expected to be associated with solar wind conditions at 0.3 - 0.5 AU from the Sun and the simplified electrodynamic feed-back anticipated for a planet lacking an ionosphere. MESSENGER observations from its 14 January 2008 Mercury flyby relevant to the occurrence of magnetic reconnection and substorms at Mercury will be discussed.

Slavin, James A.↗
NASA NTRS2009

NASA Biological Specimen Repository

The NASA Biological Specimen Repository (NBSR) has been established to collect, process, annotate, store, and distribute specimens under the authority of the NASA/JSC Committee for the Protection of Human Subjects. The International Space Station (ISS) provides a platform to investigate the effects of microgravity on human physiology prior to lunar and exploration class missions. The NBSR is a secure controlled storage facility that is used to maintain biological specimens over extended periods of time, under well-controlled conditions, for future use in approved human spaceflight-related research protocols. The repository supports the Human Research Program, which is charged with identifying and investigating physiological changes that occur during human spaceflight, and developing and implementing effective countermeasures when necessary. The storage of crewmember samples from many different ISS flights in a single repository will be a valuable resource with which researchers can validate clinical hypotheses, study space-flight related changes, and investigate physiological markers All samples collected require written informed consent from each long duration crewmember. The NBSR collects blood and urine samples from all participating long duration ISS crewmembers. These biological samples are collected pre-flight at approximately 45 days prior to launch, during flight on flight days 15, 30, 60 120 and within 2 weeks of landing. Postflight sessions are conducted 3 and 30 days following landing. The number of inflight sessions is dependent on the duration of the mission. Operations began in 2007 and as of October 2009, 23 USOS crewmembers have completed or agreed to participate in this project. As currently planned, these human biological samples will be collected from crewmembers covering multiple ISS missions until the end of U.S. presence on the ISS or 2017. The NBSR will establish guidelines for sample distribution that are consistent with ethical principles, protection of crewmember confidentiality, prevailing laws and regulations, intellectual property policies, and consent form language. A NBSR Advisory Board composed of representatives of all participating agencies will be established to evaluate each request by an investigator for use of the samples to ensure the request reflects the mission of the NBSR.

Pietrzyk, Robert↗
NASA NTRS2010

Electrostatic Power Generation from Negatively Charged, Simulated Lunar Regolith

Research was conducted to develop an electrostatic power generator for future lunar missions that facilitate the utilization of lunar resources. The lunar surface is known to be negatively charged from the constant bombardment of electrons and protons from the solar wind. The resulting negative electrostatic charge on the dust particles, in the lunar vacuum, causes them to repel each other minimizing the potential. The result is a layer of suspended dust about one meter above the lunar surface. This phenomenon was observed by both Clementine and Surveyor spacecrafts. During the Apollo 17 lunar landing, the charged dust was a major hindrance, as it was attracted to the astronauts' spacesuits, equipment, and the lunar buggies. The dust accumulated on the spacesuits caused reduced visibility for the astronauts, and was unavoidably transported inside the spacecraft where it caused breathing irritation [1]. In the lunar vacuum, the maximum charge on the particles can be extremely high. An article in the journal "Nature", titled "Moon too static for astronauts?" (Feb 2, 2007) estimates that the lunar surface is charged with up to several thousand volts [2]. The electrostatic power generator was devised to alleviate the hazardous effects of negatively charged lunar soil by neutralizing the charged particles through capacitive coupling and thereby simultaneously harnessing power through electric charging [3]. The amount of power generated or collected is dependent on the areal coverage of the device and hovering speed over the lunar soil surface. A thin-film array of capacitors can be continuously charged and sequentially discharged using a time-differentiated trigger discharge process to produce a pulse train of discharge for DC mode output. By controlling the pulse interval, the DC mode power can be modulated for powering devices and equipment. In conjunction with a power storage system, the electrostatic power generator can be a power source for a lunar rover or other systems. The negatively charged lunar soil would also be neutralized mitigating some of the adverse effects resulting from lunar dust.

Choi, Sang H.↗
NASA NTRS1976

Inductively coupled TI-MPD spacecraft electric propulsion

A nuclear electric propulsion concept using a thermionic reactor inductively coupled to a magnetoplasma-dynamic (MPD) accelerator is described and the results of preliminary analyses are presented. In this system, the thermionic generating unit operates continuously at a power level of approximately 0.4 MW, while the MPD thruster operates intermittently at higher voltages and power levels. Energy storage is provided by building up a large current in an inductor. Periodically, the charging current is interrupted and the energy stored in the magnetic field of the inductor is utilized for a short duration thrust pulse. A typical thrust pulse is characterized by a power level of 1 to 4 MWe, a duration of 1 msec, and a duty cycle of approximately 20%. Results of the preliminary analysis show that approximately 85 to 90% of the power available from the thermionic converter array can be delivered to the MPD thruster for a nominal 400 kWe system with an inductive unit suitable for a flight vehicle. Optimized values of the total specific mass of the system including the thermionic reactor, the inductor, and the MPD thruster are estimated in the range of 23 to 24 kg/kWe.

Britt, E. J.↗
NASA NTRS1981

Spinoff from a Moon Tool

Portable self-contained drill capable of extracting core samples as much as 10 feet below the surface was needed for the astronauts. Black & Decker used a specially developed computer program to optimize the design of the drill's motor and insure minimal power consumption. Refinement of the original technology led to the development of a cordless miniature vacuum cleaner called the Dustbuster. It has no hose, no cord, is 14 inches long, and also comes with a storage bracket that also serves as a recharger; plugs into a home outlet that charges the nickel cadmium batteries when not in use. Other home use cordless instruments include drills, shrub trimmers and grass shears. Company also manufactures a number of cordless tools used in the sheet metal automobile and construction industries, and a line of cordless orthopedic instruments.

Source record↗
NASA NTRS2013

No Vent Tank Fill and Transfer Line Chilldown Analysis by Generalized Fluid System Simulation Program (GFSSP)

The purpose of the paper is to present the analytical capability developed to model no vent chill and fill of cryogenic tank to support CPST (Cryogenic Propellant Storage and Transfer) program. Generalized Fluid System Simulation Program (GFSSP) was adapted to simulate charge‐holdvent method of Tank Chilldown. GFSSP models were developed to simulate chilldown of LH2 tank in K‐site Test Facility and numerical predictions were compared with test data. The report also describes the modeling technique of simulating the chilldown of a cryogenic transfer line and GFSSP models were developed to simulate the chilldown of a long transfer line and compared with test data.

Majumdar, Alok↗
NASA NTRS2021

Vertically Aligned Graphene/Metal Oxide Based Lightweight Super Strong, Energy Storage Carbon Fiber Composites

In this era of budding smart technologies, flexible and smart wearable textiles are a long awaited product which are anticipated to reach a $10 B market in few years.1 Supercapacitors are an excellent power source for these smart textiles, because they are light in weight, safe in operation, provide longer life cycle, high flexibility, and faster charge discharge capabilities.

Energy storage↗
NASA NTRS2012

Low Temperature Double-layer Capacitors with Improved Energy Density: An Overview of Recent Development Efforts

Electrochemical double-layer capacitors are finding increased use in a wide range of energy storage applications, particularly where high pulse power capabilities are required. Double-layer capacitors store charge at a liquid/solid interface, making them ideal for low temperature power applications, due to the facile kinetic processes associated with the rearrangement of the electrochemical double-layer at these temperatures. Potential low temperature applications include hybrid and electric vehicles, operations in polar regions, high altitude aircraft and aerospace avionics, and distributed environmental and structural health monitoring. State-of-the-art capacitors can typically operate to -40 C, with a subsequent degradation in power performance below room temperature. However, recent efforts focused on advanced electrolyte and electrode systems can enable operation to temperatures as low as -70 C, with capacities similar to room temperature values accompanied by reasonably low equivalent series resistances. This presentation will provide an overview of recent development efforts to extend and improve the wide temperature performance of these devices.

energy storage↗
NASA NTRS1981

Experimental simulation of latent heat thermal energy storage and heat pipe thermal transport for dish concentrator solar receiver

Test results on a modular simulation of the thermal transport and heat storage characteristics of a heat pipe solar receiver (HPSR) with thermal energy storage (TES) are presented. The HPSR features a 15-25 kWe Stirling engine power conversion system at the focal point of a parabolic dish concentrator operating at 827 C. The system collects and retrieves solar heat with sodium pipes and stores the heat in NaF-MgF2 latent heat storage material. The trials were run with a single full scale heat pipe, three full scale TES containers, and an air-cooled heat extraction coil to replace the Stirling engine heat exchanger. Charging and discharging, constant temperature operation, mixed mode operation, thermal inertial, etc. were studied. The heat pipe performance was verified, as were the thermal energy storage and discharge rates and isothermal discharges.

Narayanan, R.↗
NASA NTRS1981

Energy storage systems for MPD thrusters

Because of its high thrust density, the magnetoplasmadynamic (MPD) thruster is a promising candidate for many advanced space missions. Its high power requirements lead to operation in a pulsed mode using an intermediate energy storage device. The characteristics of a system consisting of a solar array, energy storage capacitor, and MPD thruster are studied for array powers in the range 25-375 kw. Assuming simple analytic models for the circuit components, the circuit charge and discharge equations are solved numerically, resulting in the system efficiency and capacitance. The system efficiency is inversely proportional to array power and decreases with circuit resistance. Alternative methods of energy storage such as a pulse forming network and a homopolar generator, are presented, and an overall comparison between all of the methods is given.

Gabriel, S. B.↗
NASA NTRS1977

Formation of stored heat by means of bled steam during times of load reduction and its use in peak load times

Technical possibilities and economic advantages of integrating hot water storage systems into power plants fired with fossil fuels are discussed. The systems can be charged during times of load reduction and then used for back-up during peak load periods. Investment costs are higher for such systems than for gas turbine power plants fired with natural gas or light oil installed to meet peak load demand. However, by improving specific heat consumption by about 1,000 kcal/k ohm, which thus reduces the related costs, investment costs will be compensated for, so that power production costs will not increase.

Bitterlich, E.↗
NASA NTRS1982

Design description of the Tangaye Village photovoltaic power system

The engineering design of a stand alone photovoltaic (PV) powered grain mill and water pump for the village of Tangaye, Upper Volta is described. The socioeconomic effects of reducing the time required by women in rural areas for drawing water and grinding grain were studied. The suitability of photovoltaic technology for use in rural areas by people of limited technical training was demonstrated. The PV system consists of a 1.8-kW (peak) solar cell array, 540 ampere hours of battery storage, instrumentation, automatic controls, and a data collection and storage system. The PV system is situated near an improved village well and supplies d.c. power to a grain mill and a water pump. The array is located in a fenced area and the mill, battery, instruments, controls, and data system are in a mill building. A water storage tank is located near the well. The system employs automatic controls which provide battery charge regulation and system over and under voltage protection. This report includes descriptions of the engineering design of the system and of the load that it serves; a discussion of PV array and battery sizing methodology; descriptions of the mechanical and electrical designs including the array, battery, controls, and instrumentation; and a discussion of the safety features. The system became operational on March 1, 1979.

Martz, J. E.↗