Rupert Goodwins' Diary

Sales of asbestos underpants soar as the Dell Exploding Laptop Experience starts to hit home. The unprecedented recall of 4.1 million batteries sets various new records and leaves various new questions in its wake — what actually is the fault? What other battery packs are affected? laptop battery After all, Sony makes lithium-ion cells for just about everyone. And what exactly is going to happen to the faulty cells?

I've long held lithium-ion batteries in a mixture of gratitude, resentment, fear and awe. Awe, because they store so much power — it's not unusual to see 60 watt hour packs on the back of laptops these days. Fear, because if one of those goes short-circuit, you'll get many kilowatts of energy heating up a mixture of flammable liquid and metal within inches of your danglies. Resentment, because every last manufacturer makes their own unique battery packs for each different model, and lithium-ion begins to decay from the moment it leaves the factory. No matter how carefully you use — or don't use — a pack, it'll be dead in a couple of years. And gratitude, because lithium-ion makes all sorts of fabulous things possible that just can't happen otherwise.

I'm aware that having any emotions towards battery packs is not considered normal, let alone a complex mix of four contradictory vectors. That's why I've left out tenderness — those poor things are incredibly fragile, and need constant cosseting. If you overcharge, undercharge, overdischarge, overheat, freeze, bump or merely look at one with a cutting expression, they burst into tears and, shortly afterwards, into flames. There are considerable electronic smarts in laptops, chargers and the battery packs themselves designed to guard against all those misfortunes,IBM ThinkPad R30 Battery, IBM ThinkPad R31 Battery, and it's quite possible that some miscalculation in one of those designs is behind the time bombs in our briefcases.

This is also why you can't buy lithium-ion batteries off the shelf for general use — the carnage would be impressive — and we're left with the noble but considerably less capacious nickel metal hydride cells. It also explains why, IBM Laptop Battery although lithium-ion technology was invented at Oxford University in the 1970s, it took many years before they arrived in consumer products while the safety issues were ironed out. That was thanks to Sony, which has the most experience in the field, and if it can't get it quite right we really are in trouble.

So don't hold your breath waiting for much better batteries to arrive. So far, all the technologies that are lighter and more powerful are also more dangerous. Some incredibly so, like the one that uses molten sodium chloroaluminate at 250° Celsius. Cool that, you overclockers. The rest just aren't worth bothering with. And are you prepared to switch to a laptop that weighs more and has a third of the battery life? If not, then I'm afraid asbestos underpants are the only way forward.

Researchers claim battery-life breakthrough
Stanford University researchers have made a discovery that could signal the arrival of laptop batteries that last more than a day on a single charge.

The researchers have found a way to use silicon nanowires to give rechargeable lithium-ion (Li-ion) batteries, used in laptops, iPods, video cameras and mobile phones, as much as 10 times more charge. This potentially could give a conventional Li-ion battery-powered laptop 40 hours of battery life, rather than four.

The new Li-ion batteries were developed by assistant professor Yi Cui and colleges at Stanford University's Materials Science and Engineering Department. IBM ThinkPad R31 Battery, "It's not a small improvement," Cui said. "It's a revolutionary development."

Citing their paper published in Nature Nanotechnology, Cui said the increased Li-ion battery capacity was made possible though a new type of anode that utilises silicon nanowires. Traditional Li-ion batteries use graphite as the anode, which limits the amount of lithium — which holds the charge — that can be held in the anode, and therefore limits battery life.

Silicon anodes have the "the highest theoretical charge capacity" according to Ciu's paper, but expand when charging and shrink during use: a cycle which causes the silicon to be pulverised, so degrading the performance of the battery. This dead end stumped researchers for 30 years, IBM ThinkPad R30 Battery, IBM ThinkPad R31 Battery, who instead poured their energy into improving graphite-based anodes in an effort to expand battery life.

Cui and his colleagues took this old problem and overcame it by constructing a new type of silicon nanowire anode. In Cui's anode, the lithium is stored in a forest of tiny silicon nanowires, each with a diameter one-thousandth the thickness of a sheet of paper. The nanowires inflate to four times their normal size as they soak up lithium but, unlike previous silicon anodes, they do not fracture.

Cui said there a few barriers to commercialising the technology: "We are working on scaling up and evaluating the cost of our technology.IBM ThinkPad R30 Battery, There are no roadblocks for either of these."

Cui has filed a patent on the technology and is considering formation of a company or an agreement with a battery manufacturer. He expects the battery to be commercialised and available within "several years", pending testing.