Lenovo recalls laptop batteries over fire risk

The battery problem keeps exploding.

Lenovo will recall 526,000 notebook batteries due to faulty batteries, the company said on Thursday.

The batteries were designed by Lenovo, but Sony produced the lithium ion cell. The recall affects notebooks produced from February 2005 to September 2006, according to Lenovo spokesman Ray Gorman. For now, the recall will only affect about 5 percent to 10 percent of notebooks produced by Lenovo, Gorman said, but the company recommends that all customers go to the Lenovo site and check to see if they have one of the faulty batteries.

Separately, Sony announced that it will initiate its own recall programme involving battery packs using its battery cell technology. Details will be announced later in co-operation with the US Consumer Products Safety Commission, but the programme will involve the replacement of affected battery packs "in order to address concern related to recent overheating incidents", Sony said in a press release.

With the recall, Lenovo becomes the fourth major PC manufacturer to haul batteries back due to safety problems. Dell said that it would recall 4.1 million notebook batteries in August, and Apple subsequently announced it had to recall 1.8 million notebook batteries. Toshiba, meanwhile, said this month that it would recall 340,000 batteries.

A Lenovo ThinkPad T43 caught fire at Los Angeles International Airport earlier this month. In August, Lenovo said it was speaking with Sony about the issue. While Lenovo did begin to examine the potential for problems in the wake of the Dell and Apple recalls, the PC maker said that the way it puts batteries in its hardware differs from the other companies' methods. Lenovo acquired the ThinkPad line of notebooks from IBM, which historically has been known for careful design.

The problem with the recalled notebook batteries rests with lithium ion battery cells made by Sony. PC makers and component suppliers buy these cells and design batteries around them. These battery cells can provide several hours of electricity to notebooks, but the liquid inside them is flammable. If a short takes place, a chain chemical reaction can occur that melts the battery or causes the notebook to explode. Lenovo inserts technology into its batteries to prevent chain reactions and has contemplated licensing it to others.

Like the gas tank in a car, lithium ion batteries in most instances are safe. However, to extend battery life, battery makers have been putting more flammable liquid into these batteries, and making other parts inside the batteries smaller and thinner. This, in turn, increases the potential problem, as it is more likely that thinner materials will come loose and interfere with the proper working of the battery cell.

Back in 2004, Sony execs said lithium ion technology would be likely to hit its limit in 2006.

Start-ups and venture capitalists are tinkering with alternatives to lithium ion, such as zinc-based batteries, but these are not available yet.