http://www.zoomilife.com/2008/11/25/...acity-by-1000/

In what could potentially be a revolutionary breakthrough for everything from laptops to electric cars, a South Korean team of researchers have made a major discovery in Lithium-Ion battery technology. A team of researchers at South Korea’s Hanyung University, led by professor Cho Jaephil, has claimed a discovery that could extend lithium ion battery energy capacity by up to 1000% or more.

The key to Jaephil’s discovery was the application of a three-dimensional porous silicon graphite material which has the ability of holding up to ten times the number of lithium ions as conventional graphite cathodes. Patents have already been applied for. from the press release:

Lithium ion accumulator batteries produce current by moving lithium ions. The battery usually contains a cathode (positive electrode) made of a mixed metal oxide, such as lithium cobalt oxide, and an anode (negative electrode) made of graphite. While the battery is being charged, lithium ions migrate into the anode, where they are stored between the graphite layers. When the battery is being discharged, these ions migrate back to the cathode.

It would be nice to have an anodic material that could store more lithium ions than graphite. Silicon presents an interesting alternative. The problem: silicon expands a great deal while absorbing lithium ions (charging) and shrinks when giving them up (discharging). After several cycles the required thin silicon layers are pulverized and can no longer be charged.

Cho’s team has now developed a new method for the production of a porous silicon anode that can withstand this strain. They annealed silicon dioxide nanoparticles with silicon particles whose outermost silicon atoms have short hydrocarbon chains attached to them at 900 °C under an argon atmosphere. The silicon dioxide particles were removed from the resulting mass by etching. What remained were carbon-coated silicon crystals in a continuous, three-dimensional, highly porous structure.
If this is for real, it could have a huge impact on the electric vehicle industry. For example, the Tesla Roadster currently gets about 150-200 miles per charge. Imagine having an electric car that gets 1600 miles per charge, with a full charge costing you less than a regular tank of gas. You’re getting more miles for less money, with no fossil fuel use - especially if your electrity comes from a renewable source.