Original URL: http://www.theregister.co.uk/2011/09/12/scientists_make_batteries_from_polymer_gel/

Laptop batteries made of jelly invented

Wibble-wobble wibble-wobble 'leccy on a plate

By Brid-Aine Parnell

Posted in Science, 12th September 2011 11:41 GMT

Jelly could be the answer to the problem of cheaper batteries for electronics, according to some boffins over at Leeds University.

They've come up with a type of polymer gel that could replace the liquid electrolytes used in rechargeable lithium cells. And of course, because it's jelly-like, it can be moulded into all shapes and sizes to suit the device it's intended for.

"The polymer gel looks like a solid film, but it actually contains about 70 per cent liquid electrolyte," says Professor Ian Ward, head honcho on the project. "It's made using the same principles as making a jelly: you add lots of hot water to 'gelatine' - in this case a polymer and electrolyte mix - and as it cools it sets to form a solid but flexible mass."

The technology has already been licensed to an American company, Polystor Energy Corporation, which is conducting trials to get the jelly-cells ready for use in portable electronics.

The benefits of the new tech are the usual good ones - safer, cheaper and lighter. Rechargeable lithium-ion batteries are currently the top choice for laptops, phones, cameras and other mobile devices, but they're not always the most reliable. Big tech firms like Dell and HP often have battery issues leading to big recall programmes, including the off-chance that they might explode or catch fire.

With the jelly-cells, the lamination manufacturing process used to make them "seals the electrodes together so that there is no excess flammable solvent and liquid electrolyte" - so much less chance of fire or explosion then.

That same process, where the jelly is sandwiched between an anode and a cathode at high speed, gets you a cell that's highly conductive but just nanometres thick. And, luckily for mass production, making the cells this way is "fast, efficient and low cost". ®