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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 1,711 records · Page 95
All sourcesNASA NTRSDOE OSTI
DOE OSTI2018

Permeation testing of thermal power plant cooling water impacts of Graphite Oxide (GO)/polymer membranes

The purpose of this project was to investigate how thermoelectric power plant cooling water impacts the energy demands, permeance, and ion rejection of GO/polymer membranes using extended permeation testing. Treatment of cooling tower blowdown water is challenging since this water contains scalants (e.g.: silica, calcium sulfate, calcium carbonate) which can precipitate on membranes, decreasing membrane efficiency and lifetime. In this collaboration with EPRI and a Southwestern US utility, the performance of GO/polymer membranes in desalinating cooling tower blowdown water from three natural-gas fueled power plants was evaluated. Results of cross-flow desalination test durations of three to four weeks demonstrated the long-term stability of the membranes. GO/polymer desalination membranes were shown to tolerate drinking-water level chlorination, which could reduce capital and operational costs. Biofouling and scale formation were minimal on the GO surface, suggesting that industry standard intensive cleaning steps could be reduced. Results also demonstrated pressure-tunable rejection which would allow treat-to-need water recycling, thus likely reducing energy costs for these membranes. Further development of biofouling and scaling resistant desalination membranes could lead to reduced cost for water treatment, potentially allowing for greater use of non-traditional water supplies for thermoelectric power plants.

Biedermann, Laura↗
DOE OSTI2019

Graphite Steel and Chromium-Nickel Steel Corrosion: Solution Flow Through Corrosion Experiments

The corrosion of steel, when exposed to various compositions of brines is a complex, heterogeneous process involving dissolution and precipitation of multiple solids. The rate at which elements will be released from the corrosion process under these conditions will depend, in part, on effects associated with secondary alteration phases (passivating film) that may potentially form under these conditions. Understanding these processes has required the development of sophisticated methods to sample and quantitatively characterize the composition of the steel as it corrodes and releases elements. The determination of the concentrations of both brine and steel corrosion components in solutions sampled from these tests is required to fully understand the process that may eventually lead to dissolution of corrosion products.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗
DOE OSTI2021

Rapid charging made practical in graphite-based lithium batteries: surface-acoustic wave turbulent electrolyte mixing to overcome diffusion limited charging rates [Final Report]

One of the key limits in rapidly recharging a lithium-ion battery is the depletion of lithium ions within the electrolyte adjacent the anode during charging and long diffusion time to overcome this depletion. It also causes dendrite formation, inefficient use of the lithium, and battery degradation over many charge-discharge cycles. Because the liquid electrolyte remains quiescent and unmixed, this depletion layer’s depth rapidly grows to match the anode-cathode separation distance at even modest charge rates. The solution proposed by PI Prof. James Friend and Co-PI Prof. Ping Liu, both from the University of California, San Diego, is to mix the electrolyte and minimize the Li+ ion concentration gradient during charging. Even in the presence of the separator, the charging rate could then be significantly increased. They propose to accomplish this using surface acoustic wave (SAW)-driven acoustic streaming, a technique employing 10-mW fingernail-sized solid-state devices from the telecommunications industry to drive turbulent mixing to submicron length scales in a manner completely compatible with the typical 20700 and 18650 cells used in electric vehicles. 0.1. Turbulent acoustic streaming mixes the electrolyte during charging—even with separator Our proposed 100-MHz SAW device used to recirculate the electrolyte is compatible with lithium- ion battery electrochemistry, as it is made in our lab of single-crystal lithium niobate. Their solution is straightforward to drive from a DC power source alongside the signal provided during battery charging. The device is only needed during charging and does not consume power dur- ing battery discharge. Uniquely, SAW generates extreme accelerations of over 1 billion meters per second squared in the fluid, driving turbulent mixing from centimeter to submicron length scales, even through the porous separator materials that tend to be used in batteries, all while avoiding interfering with the anode’s solid electrolyte interphase layer that forms during use. By employing novel fluid mechanics, the investigators are proposing a new direction for battery research away from direct use of materials science and electrochemistry. The chemistry agnostic solution may be employed in any battery chemistry that makes use of liquid electrolytes, providing a broader transformative benefit to the battery research community. They are to produce a series of prismatic and 20700-cell sized 2 Ah batteries capable of being charged and discharged at least 500 times without more than 20% loss in battery capacity, and to provide analysis tools useful to the battery research and development community for adopting this approach for other battery chemistries and configurations.

25 ENERGY STORAGE↗
DOE OSTI2022

Review of Potential Wigner Effect Impacts on the Irradiated Graphite in Decommissioned Hanford Reactors

This review of is motivated by the need to consider future disposal of the nine surplus Hanford Site production reactors (B, C, D, DR, F, H, KE, KW, and N) that are decommissioned as part of the Hanford Site Composite Analysis. The B Reactor has been designated as a museum. The other eight reactors will be evaluated in a future performance assessment before a final disposal facility can be authorized to construction or to receive this waste form. After a performance assessment is available, then the Hanford Site Composite Analysis would be updated to account for this additional source term. Disposal is currently assumed to occur in calendar year 2070 by one-piece removal to a projected disposal facility in the 200 West Area of the Hanford Site Central Plateau. The N Reactor core may also be disposed analogously to the single-pass reactors. It will further assume that the B Reactor will remain a museum permanently. The U.S. Department of Energy studied at least five decommissioning alternatives for long-term, safe management of radionuclide-contaminated materials inside the eight single-pass reactors (DOE/EIS-0119-FEIS, Decommissioning of Eight Surplus Production Reactors at the Hanford Site, Richland, Washington).

11 NUCLEAR FUEL CYCLE AND FUEL MATERIALS↗
DOE OSTI2022

Enabling Extreme Fast Charging through Control of Li Deposition Overpotential on Graphite Electrodes

Currently produced electric vehicles (EVs) rely on the use of lithium ion battery technology due to its high energy and power density. However, a major barrier facing the adoption of electric vehicles is that currently utilized Li-ion batteries take significantly longer to recharge (~ 30 minutes) compared to the time necessary to refuel vehicles powered by internal combustion engines (< 10 minutes). Thus, the need to develop Li-ion batteries which can be charged in approximately 10 minutes (6 C rate) without sacrificing range, cost, or cycle life is critical for the widespread implementation of EVs.

25 ENERGY STORAGE↗