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Thin beta-alumina electrolyte membrane used in a new, planar sodium-beta battery design being developed by EPT and PNNL. (Credit: PNNL.)

According to a Pacific Northwest National Lab press release, a team of researchers at PNNL and EaglePicher Technologies is developing a large-scale battery that could enable the widespread use of renewable energy sources by providing grid-scale energy storage. The work is part of an ARPA-E grant awarded to EaglePicher Technologies, a battery developer.

Researchers argue that the most promising technology for large-scale energy storage is the sodium-beta battery; however, current sodium-beta batteries are limited by reliability issues and excessive cost. The next generation of sodium-beta battery will incorporate a planar design instead of today’s tubular sodium-beta batteries.

PNNL estimates that the new sodium-beta battery could reduce carbon dioxide emissions by 150 million tons per year in the United States alone.

The key to the EPT-PNNL approach is using a planar, stacked, modular battery design that employs thinner electrolyte materials. These materials will enable an estimated 30 percent reduction in operating temperature.

Planar designs also allow greater stacking efficiency, resulting in a 30 percent increase in energy density. Manufacturing processes are simplified and process yields are improved when fabricating planar, rather than tubular, ceramic components, leading to the reduction of fabrication costs by a factor of 10 over current tubular batteries.

The EPT-PNNL team expects to develop a prototype battery over the next three years. During this time, researchers at PNNL will focus on developing thin ceramic electrolyte materials, planar cell design and fabrication and advanced sealing technology. EPT has the lead responsibility for battery design, systems controls, testing and, eventually, full-scale manufacturing of battery modules.

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Sandia National Lab and the National Renewable Energy Lab have just unveiled a nice, new tool: a 180-teraflop supercomputer designed and built by the Sun/Oracle and Intel corporations. The specs for the computer, nicknamed Red Mesa, were developed jointly by SNL and NREL, although the computer is physically located at SNL.

Red Mesa is the newer, faster cousin of SNL’s 160 tera-flop Red Sky supercomputer installed last year. The two can work in tandem to produce a system whose top speed can reach a total speed of 500 teraflops.

From a DOE release on the computers:

The work for the first time brings defense-scale computing to bear on alternative energy projects that otherwise could take months or even years to complete if researchers had to rely on more limited computing resources or on physical testing.

Joe Polito, Sandia vice president of Enterprise Transformation, called Red Mesa “a state-of-the-art computing platform to address pressing energy problems for the country, using the most energy-efficient supercomputer in the country.”

Megan McCluer, DOE program manager for wind and hydropower technologies, said, “The Red Mesa platform will provide the speed and scale needed to perform large-scale computations targeted toward the continued improvements of clean energy technologies.”

 

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I continue to be really impressed with 1366 Technologies’ technical work and and business strategy. Now DOE has put together a short (4 minutes) video about 1366’s Direct Wafer Technology silicon wafer production system and why ARPA-E has provided the company with $4 million to continue their efforts. There isn’t a lot of depth here, but it is a nice, easy-to-understand promo piece for both 1366 and DOE/ARPA-E.

For more on 1366, see

1366 Technologies demonstrates directly manufactured silicon PV wafer

Part 1: New busbars, ‘fingers’ to cut costs by 20%

Part 2: Process improvements versus science breakthroughs

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Credit: University of Pennsylvania

A group out of University of Pennsylvania’s Department of Mechanical Engineering and Applied Mechanics thinks it knows why, at nanoscales, the friction encountered by, say, an atomic force microscope, increases as the number of layers decrease: The AFM tip pushes material in front into sort of a wrinkle or wave in front, and stretches it in the back. This pucker in the material creates a force that pushes back on the AFM  tip.

The effect is sort of like what would happen if you quickly tried to push an area rug on a slick floor. In the case of nanoscale materials, the fewer the layers, the easier it is for it to bunch up in front of the AFM.

The researchers, whose work is published in Science, say that after testing atomically thin samples of four  materials they think this may be a universal characteristic for any material at this scale. The materials tested were graphene, molybdenum disulfide, hexagonal-boron nitride and niobium diselenide. The researchers test a range of thickness, from several atomic layers all the down to a single layer, and then compared the friction to that found in bulk quantities of these materials.

Compared to the bulk material, the researchers found that friction progressively increased as the number of layers is decreased.

Research co-leader Robert Carpick says in a Penn release that, “We call this mechanism, which leads to higher friction on thinner sheets, the ‘puckering effect.’ Interatomic forces, like the van der Waals force, cause attraction between the atomic sheet and the nanoscale tip of the atomic force microscope which measures friction at the nanometer scale.”

Here is a brief animation of what goes on:

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He says that thicker sheets cannot deflect as easily because they are much stiffer. The material can’t bunch up as easily so the increase in friction is less pronounced.

The researchers also found a logical to prevent the increase in friction. Continuing with my analogy, an area rug won’t bunch up if the special Home Depot double-sided tape is used. Likewise, if the atomic sheets are strongly bound to a substrate, such as mica, the problem disappears.

Carprick and his group say that this will have practical implications for the design of nanomechanical devices that use graphene, and will will shed more light on the macroscopic behavior of common lubricants, such as graphite, MoS2 and BN.

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According to a NASA Tech Brief, the Next Generation Space Telescope - aka, the James Webb Space Telescope – will be using electrostrictive ceramic actuators that can function at low temperatures to control the shapes of mirrors.

The actuators, developed by two ACerS members, Maureen L. Mulvihill and Mark A. Ealey of Xinetics, a division of Northrup Grumman in Devens, Mass., can achieve a relatively large stroke in the low-temperature ranges that the telescope will encounter, i.e., in the area of 30–60 K. This stroke will be used to adjust the shape of the mirrors used by the telescope.

Unlike the Hubble telescope that used a single primary mirror, the JWST will a mirror composed of 18 hexagonal segments, which will unfold and be adjusted after the telescope is launched.

According to Mulvihill and Ealey, besides use in deep space, the electroactive ceramic material may be of interest to companies for fine control of the positions of objects in cryogenic laboratory apparatuses and in industrial cryogenic (including superconducting) systems.

NASA offers a download of a Xinetics PowerPoint presentation on Xinetic’s work here.

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