Search NASA⌕ Search

SEARCH · Search NASA

Results for “Hydrogen storage”

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.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 163 records · Page 9

A simple approach to metal hydride alloy optimization

Certain metals and related alloys can combine with hydrogen in a reversible fashion, so that on being heated, they release a portion of the gas. Such materials may find application in the large scale storage of hydrogen. Metal and alloys which show high dissociation pressure at low temperatures, and low endothermic heat of dissociation, and are therefore desirable for hydrogen storage, give values of the Hildebrand-Scott solubility parameter that lie between 100-118 Hildebrands, (Ref. 1), close to that of dissociated hydrogen. All of the less practical storage systems give much lower values of the solubility parameter. By using the Hildebrand solubility parameter as a criterion, and applying the mixing rule to combinations of known alloys and solid solutions, correlations are made to optimize alloy compositions and maximize hydrogen storage capacity.

Lawson, D. D.↗

Storage, transmission and distribution of hydrogen

Current practices and future requirements for the storage, transmission and distribution of hydrogen are reviewed in order to identify inadequacies to be corrected before hydrogen can achieve its full potential as a substitute for fossil fuels. Consideration is given to the storage of hydrogen in underground solution-mined salt caverns, portable high-pressure containers and dewars, pressure vessels and aquifers and as metal hydrides, hydrogen transmission in evacuated double-walled insulated containers and by pipeline, and distribution by truck and internal distribution networks. Areas for the improvement of these techniques are indicated, and these technological deficiencies, including materials development, low-cost storage and transmission methods, low-cost, long-life metal hydrides and novel methods for hydrogen storage, are presented as challenges for research and development.

Kelley, J. H.↗

The Safe Removal of Frozen Air from the Annulus of an LH2 Storage Tank

Large Liquid Hydrogen (LH2) storage tanks are vital infrastructure for NASA. Eventually, air may leak into the evacuated and perlite filled annular region of these tanks. Although the vacuum level is monitored in this region, the extremely cold temperature causes all but the helium and neon constituents of air to freeze. A small, often unnoticeable pressure rise is the result. As the leak persists, the quantity of frozen air increases, as does the thermal conductivity of the insulation system. Consequently, a notable increase in commodity boil-off is often the first indicator of an air leak. Severe damage can result from normal draining of the tank. The warming air will sublimate which will cause a pressure rise in the annulus. When the pressure increases above the triple point, the frozen air will begin to melt and migrate downward. Collection of liquid air on the carbon steel outer shell may chill it below its ductility range, resulting in fracture. In order to avoid a structural failure, as described above, a method for the safe removal of frozen air is needed. A thermal model of the storage tank has been created using SINDA/FLUINT modeling software. Experimental work is progressing in an attempt to characterize the thermal conductivity of a perlite/frozen nitrogen mixture. A statistical mechanics model is being developed in parallel for comparison to experimental work. The thermal model will be updated using the experimental/statistical mechanical data, and used to simulate potential removal scenarios. This paper will address methodologies and analysis techniques for evaluation of two proposed air removal methods.

cryogenic insulation↗

Hydrogen Fire in a Storage Vessel

On October 23, 2007, the operations team began a procedure to sample the Liquid Hydrogen (LH2) storage vessels ("tanks"), and associated transfer system. This procedure was being performed to determine the conditions within the system, and if necessary, to purge the system of any excess Gaseous Hydrogen (GH2) in preparation for reactivation of the system. The system had not been used since 2003. The LH2 storage system contains two (2) spherical pressure vessels of 225,000 gallons in volume, with a maximum working pressure (MAWP) of 50 psig. Eight inch transfer piping connects them to the usage point. Operations began with activation of the burnstack for the LH2 storage area. Pneumatic (GN2) systems in the storage area were then activated and checked. Pressurization of storage tank number 1 with gaseous nitrogen (GN2) was initiated, with a target pressure of 10 psig, at which point samples were planned to be taken. At 5 psig, a loud noise was heard in the upper area of tank number 2. Smoke was seen exiting the burnstack and from the insulation on vent lines for both tanks. At this time tank number 1 was vented and the pressurization system was secured. The mishap resulted in physical damage to both storage tanks, as well as to some of the piping for both tanks. Corrective action included repair of the damaged hardware by a qualified contractor. Preventive action included documented organizational policy and procedures for establishing standby and mothball conditions for facilities and equipment, including provisions as detailed in the investigation report recommendations: Recommendation 1: The using organization should define necessary activities in order to place hydrogen systems in long term periods of inactivity. The defined activities should address requirements for rendering inert, isolation (i.e., physical disconnect, double block and bleed, etc.) and periodic monitoring. Recommendation 2: The using organization should develop a process to periodically monitor hazardous systems for proper configuration (i.e., a daily/weekly/monthly check sheet to verify critical purges are active).

Hester, Zena M.↗

Status and Design Concepts for the Hydrogen On-Orbit Storage and Supply Experiment

This paper studies concepts for the Hydrogen On-Orbit Storage and Supply Experiment (HOSS). HOSS is a space flight experiment whose objectives are: Show stable gas supply for storage and direct gain solar-thermal thruster designs; and evaluate and compare low-g performance of active and passive pressure control via a thermodynamic vent system (TVS) suitable for solar-thermal upper stages. This paper shows that the necessary experimental equipment for HOSS can be accommodated in a small hydrogen dewar of 36 to 80 liter. Thermal designs for these dewars which meet the on-orbit storage requirements can be achieved. Furthermore ground hold insulation and shielding concepts are achieved which enable storing initially subcooled liquid hydrogen in these small dewars without venting in excess of 144 hours.

Chato, David J.↗

Variable-volume atomic storage vessel for hydrogen masers

Vessel, located in maser cavity, is made from cylindrical, convoluted flexible bellows which can be expanded or contracted along the cylinder axis vertically. Inner surface area remains constant with changing volume, permitting measurement of frequency deviations of excited atoms.

Peters, H. F.↗

Synthesis of Single Wall Carbon Nanotubes by Plasma Arc: Role of Plasma Parameters

Single wall carbon nanotubes (SWNT) are porous objects on the molecular scale and have a low density, which gives them potential applications as adsorbent for molecular hydrogen. Their H2 absorption capacity published in the literature varies from 4 to 10% by mass according to the purity of the materials and storage conditions. Optimization of production methods of SWNTs should permit improving these new materials for storage of hydrogen. In this article, we show the potential of using SWNTs in hydrogen storage. In particular, we pose problems associated with synthesis, purification, and opening up of the nanotubes. We present an electric arc process currently used at laboratory scale to produce single wall carbon nanotubes. We discuss, in particular, operating conditions that permit growth of nanotubes and some plasma parameters that assure control of the material. Analysis of the process is carried out with the aid of local measurements of temperature and scanning and transmission electron microscopy of the materials.

Farhart, Samir↗

Nickel-hydrogen capacity loss on storage

A controlled experiment evaluating the capacity loss experienced by nickel electrodes stored under various conditions of temperature, hydrogen pressure, and electrolyte concentration was conducted using nickel electrodes from four different manufacturers. It was found that capacity loss varied with respect to hydrogen pressure, and storage temperature as well as with respect to electrode manufacturing processes. Impedance characteristics were monitored and found to be indicative of electrode manufacturing processes and capacity loss. Cell testing to evaluate state-of-charge effects on capacity loss were inconclusive as no loss was sustained by the cells tested in this experiment.

Manzo, Michelle A.↗

Nickel-hydrogen capacity loss on storage

A controlled experiment evaluating the capacity loss experienced by nickel electrodes stored under various conditions of temperature, hydrogen pressure, and electrolyte concentration was conducted using nickel electrodes from four different manufacturers. It was found that capacity loss varied with regard to hydrogen pressure and storage temperature, as well as with regard to electrode manufacturing processes. Impedance characteristics were monitored and found to be indicative of electrode manufacturing processes and capacity loss. Cell testing to evaluate state-of-charge effects on capacity loss were inconclusive as no loss was sustained by the cells tested in this experiment.

Manzo, Michelle A.↗

Considerations for Storage of High Test Hydrogen Peroxide (HTP) Utilizing Non-Metal Containers

When working with high concentrations of hydrogen peroxide, it is critical that the storage container be constructed of the proper materials, those which will not degrade to the extent that container breakdown or dangerous decomposition occurs. It has been suggested that the only materials that will safely contain the peroxide for a significant period of time are metals of stainless steel construction or aluminum use as High Test Hydrogen Peroxide (HTP) Containers. The stability and decomposition of HTP will be also discussed as well as various means suggested in the literature to minimize these problems. The dangers of excess oxygen generation are also touched upon.

Moore, Robin E.↗

Air Force NiH2 IPV storage testing

USAF Phillips Laboratory Nickel Hydrogen IPV storage test, performed at the Naval Surface Warfare Center (NSWC) at Crane Indiana, is discussed. The storage tests is just one component of the USAF Phillips Laboratory Nickel Hydrogen IPV Test Program. The plan was to store cells for a defined period and cycle matching cells to determine the effect on cycle life. The storage period was completed in April 95 and the cycling cells have achieved five years of real time LEO cycling. The two main objectives of the storage test are: to investigate various methods on NiH2 cells by using two different manufacturers and two different storage methods or conditions, and to determine the effect of storage method on cycle performance and cycle life by using matching cells cycling at 25% depth of discharge. The comparisons between individual cycle performance as well as cycle life are also reported. During the test the following variables has been considered: constant potential, cell current, open circuit voltage, and temperature. The results of the test are also discussed using charts and tables.

Smellie, Shawn↗

Design Concepts Studied for the Hydrogen On-Orbit Storage and Supply Experiment

The NASA Lewis Research Center, in conjunction with the Utah State University Space Dynamics Laboratory, studied concepts for the Hydrogen On-Orbit Storage and Supply Experiment (HOSS). HOSS is a space flight experiment whose objectives are (1) to show stable gas supply for solar-thermal thruster designs by using both storage and direct-gain approaches and (2) to evaluate and compare the low-gravity performance of active and passive pressure control via a thermodynamic vent system (TVS) suitable for solar-thermal upper stages. This study showed that the necessary experimental equipment for HOSS can be accommodated in a small hydrogen Dewar (36 to 80 liter). Thermal designs can be achieved that meet the on-orbit storage requirements for these Dewars. Furthermore, ground hold insulation concepts are easily achieved that can store liquid hydrogen in these small Dewars for more than 144 hr without venting.

Chato, David J.↗

An improved storage bulb mount for DSN hydrogen masers

The presently used JPL hydrogen maser suspended atomic storage bulb and a rigid, single-plane mounted bulb are compared. The new bulb incorporates three major design changes: (1) mounting design; (2) alterations to the collimator; and (3) decrease in mass. These design changes are expected to increase the long-term stability of the frequency standard by reducing its sensitivity to vibration and thermal effects.

Dachel, P. R.↗

Material processing with hydrogen and carbon monoxide on Mars

Several novel proposals are examined for propellant production from carbon dioxide and monoxide and hydrogen. Potential uses were also examined of CO as a fuel or as a reducing agent in metal oxide processing as obtained or further reduced to carbon. Hydrogen can be reacted with CO to produce a wide variety of hydrocarbons, alcohols, and other organic compounds. Methanol, produced by Fischer-Tropsch chemistry may be useful as a fuel; it is easy to store and handle because it is a liquid at Mars temperatures. The reduction of CO2 to hydrocarbons such as methane or acetylene can be accomplished with hydrogen. Carbon monoxide and hydrogen require cryogenic temperatures for storage as liquids. Noncryogenic storage of hydrogen may be accomplished using hydrocarbons, inorganic hydrides, or metal hydrides. Noncryogenic storage of CO may be accomplished in the form of iron carbonyl (FE(CO)5) or other metal carbonyls. Low hydrogen content fuels such as acetylene (C2H2) may be effective propellants with low requirements for earth derived resources. The impact on manned Mars missions of alternative propellant production and utilization is discussed.

Hepp, Aloysius F.↗