Posted 03/17/10 at 08:16:21 AM by Pulkit Chandna

A hunt for lithium-ion batteries is likely to reveal quite a few of them inside a standard home, with a host of gadgets tapping into them these days. In fact, Li-ion batteries are gaining ground in other key industries, including hybrid automobiles and alternative energy. Now, a new breakthrough promises Li-ion batteries with vastly improved performance.

Researchers at Georgia Institute of technology have devised a new "bottom-up" self-assembly technique to overcome technical difficulties that had rendered more efficient silicon-based anodes impractical. The current crop of batteries only feature anodes made from graphite.

But the new technique uses “nanotechnology to fine-tune its materials properties,” allowing silicon-based anodes to be  more stable inside the battery, and thereby paving the way for “a ten-fold capacity improvement over graphite.”  Not only will the new technique improve the storage capacity of Li-ion batteries manifold, but such batteries will also last much longer.

"Development of a novel approach to producing hierarchical anode or cathode particles with controlled properties opens the door to many new directions for lithium-ion battery technology," said Gleb Yushin, an assistant professor in the School of Materials Science and Engineering at the Georgia Institute of Technology. "This is a significant step toward commercial production of silicon-based anode materials for lithium-ion batteries."

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Posted 02/05/10 at 04:52:12 PM by Bart Salisbury

File this one away for the future: graphene transistors. Graphene makes use of carborn rather than silicon, and transistors produced from it are capable of operating at 100 gigahertz, or about ten times faster than the fastest silicon transistors. And IBM has figured out a way to make production of these little beauties commercially feasible.

Graphene transistors aren’t new. But the methods for making them are clumsy and inefficient. For example, sheets of graphene would be flaked away from graphite--a tricky process at best. And it could only produce transistors with speeds up to 26 gigahertz.

IBM has devised a method for ‘growing’ graphene transistors on the surface of a two-inch silicon carbide wafer. The wafter is heated until the silicon evaporates, leaving behind a thin layer of epitaxial graphene, from which a transistor is produced. In addition, IBM improved the process by using better materials for parts of the transistor, such as the insulator.

Speedier transistors translate into speedier computing. Graphene transistors, therefore, hold promise for bumping up hardware potential on motherboards and add-in cards. (Not CPUs, though--graphene won’t work for CPUs.) While things will get speedier, for us it won’t be right away. Projected first applications will be in military devices. After that, maybe, graphene transistors will work their way into consumer electronics.

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Posted 11/06/08 at 05:28:49 PM by Andy Salisbury

Minds at the University of Wisconsin-Madison have created a method to calculate how different degrees of strain affect electronic structures in silicon. Sound confusing? Well, truthfully it is, but it could soon bring you new CPUs that produce much less heat and use less power.

Today’s strained silicon is very limited. This is mostly caused by the techniques that are in place to create it, and the physics of strain (which still haven’t been fully mapped out). But, thanks to a team of dedicated researchers led by Max Lagally, the Professor of Materials Science and Engineering at UW-M, this is all about to change.

The creation process, which previously didn’t always provide a uniform stretch of the silicon across the surface of the chip, has been drastically changed thanks to the research of Legally’s team. Having mapped out the effects of strain on electric structures in silicon, they finally understand why there are drastic increases and decreases in electron mobility from sheet to sheet. This will allow them a more uniform creation process that will produce more predictable results.

To produce their samples they stretched out films of silicon for research. “Imagine [attaching] a ring and a hook to all four corners [of a piece of thin film silicon] and pulling equally on all four corners like a trampoline,” said Legally, “it stretches out like that.”

Should this research come full circle, there’s no doubt that we’ll all reap the rewards.

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Posted 10/16/08 at 04:52:21 PM by Andy Salisbury

Thermoelectric materials are common, but they’re not used as often as one would expect. This is because these materials have either been inefficient, expensive, or both. Several groups of researchers have been looking to correct this, and solve the mysteries that have been surrounding these compounds with a goal of bringing them to the world.

Mildred S. Dresselhaus is one of those looking to change the face of thermoelectric compounds. Working with her team at the Massachusetts Institute of Technology she’s looking to create more efficient materials by manufacturing tiny particles or wires into them to disrupt the flow of head. These particles and wires would make the materials that are already great conductors much more competent at dispersing heat.

Professor Peidong Yang’s team at the University of California at Berkely is searching for entirely new materials. While silicon isn’t a great thermoelectric material, once you look at it in nanoscale, things change. Silicon nanowires have been shown to be one hundred times more efficient at conserving energy than bulk silicon.

Where things really start to get interesting are at the University of Århus, Risø-DTU (say that three times fast) and the University of Copenhagen where they’ve unlocked a secret of certain thermoelectric compounds which might potentially help in developing more efficient materials.

There are several other teams working on pushing the technology of thermoelectric based compounds, and they’re looking to implement them in a multitude of places, including your PC.

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Posted 03/04/08 at 07:18:51 PM by One4yu2c

AMD details Puma platform, Pioneer pulls the plug on plasma, find out what Nike and iPod are up to, and much more!

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