- Number 406 |
- February 3, 2014
Lithium batteries, with their exceptional ability to store power per a given weight, have been a major focus of research to enable use in everything from portable electronics to electric cars. Now researchers at Massachusetts Institute of Technology (MIT) and DOE's Brookhaven Lab have found a whole new avenue for such research: the use of disordered materials, which had generally been considered unsuitable for batteries.
In a rechargeable lithium-based battery, lithium ions — atoms that have given up an electron, and thus carry a net charge — are pulled out of the battery's cathode during the charging process, and returned to the cathode as power is drained. But these repeated round-trips can cause the electrode material to shrink and expand, leading to cracks and degrading performance over time.
A "hybrid" anode developed at DOE’s Pacific Northwest National Laboratory could quadruple the life of lithium-sulfur batteries; if these batteries can just overcome a few technical hurdles, they could power electric vehicles for longer distances before needing to charge and could save solar energy for a rainy day. The national lab’s research describing the anode's design and performance, bringing it closer to commercial use, recently appeared in Nature Communications.
"Lithium-sulfur batteries could one day help us take electric cars on longer drives and store renewable wind energy more cheaply, but some technical challenges have to be overcome first," said PNNL Laboratory Fellow Jun Liu, who is the paper's corresponding author. "PNNL's new anode design is helping -- bringing us closer to that day."
Scientists and engineers working on the design of the particle detector for the proposed Long-Baseline Neutrino Experiment celebrated a major success in January. They operated for the first time a 35-ton prototype cryostat filled with liquid argon and met the stringent, less-than-200-parts-per-trillion purity requirement on oxygen contamination in the liquid.
The purity of liquid argon is crucial for the proposed LBNE neutrino detector. Oxygen and other electronegative impurities in the liquid can absorb ionization electrons created by neutrino interactions and prevent them from reaching the signal wires of the detector.
Scientists at DOE's Ames Laboratory have demonstrated broadband terahertz (THz) wave generation using metamaterials. The discovery may help develop noninvasive imaging and sensing, and make possible THz-speed information communication, processing and storage.The team created a metamaterial made up of a special type of meta-atom called split-ring resonators. Split-ring resonators, because of their u-shaped design, display a strong magnetic response to any desired frequency waves in the THz to infrared spectrum.