While gadgets improve by leaps and bounds every year, the technology that powers them hasn't. Batteries still suck, unless something comes of this research at Northwestern University that promises new lithium-ion alternatives that charge 10 times faster with 10 times the capacity.
Inside a battery, lithium ions travel between an anode and a cathode, passing through an electrolyte in the process. During charging, the speed at which those ions can get from the electrolyte to the anode affects how quickly a battery can be replenished. The ions have to pass between layers of thin graphene sheets, but in order to do so they must travel all the way to the edges first. This ends up creating mini ionic traffic jams, slowing down the charging process. So to improve this, the engineers used a chemical oxidation process to punch minuscule holes in the graphene sheets, essentially giving lithium ions a shortcut to the anode.
To increase the capacity of a lithium-ion battery, the team also sandwiched clusters of silicon between those graphene sheets. In a traditional battery carbon is used, which can only accommodate one lithium atom for every six carbon atoms. But for every silicon atom, four lithium atoms can be accommodated, which drastically increases a battery's capacity. And by sandwiching the silicon between the flexible graphene sheets, they also found a way to deal with silicon's tendency to expand and contract which has traditionally made it impractical for use in batteries.
Now that they've improved the anode, the researchers at Northwestern are hoping to find ways to improve the cathode as well, and are optimistic that their developments will make their way into commercial products in as little as three years. Three years?! If there's even the slightest chance this breakthrough delivers as promised, and I can actually use my phone as a phone without worrying about killing the battery, I want it now! [Northwestern University via Engadget]