Laptop Battery Safety

On August 14, Dell announced a massive recall of 4.1 million notebook batteries because of a potential fire hazard. The lithium ion batteries, made by Sony, were installed in Dell notebooks sold between April 2004 and July 18, 2006; 2.7 million were sold in the United States.
Soon after, Apple announced a recall of 1.8 million lithium ion batteries for its iBook and PowerBook notebooks. These batteries were also made by Sony.
Apple's announcement was followed by one from Panasonic, which said it was recalling 6000 laptop battery packs because of potential overheating. Panasonic's recall only affects laptops shipped to Japan. The company wouldn't identify the battery manufacturer.
(EDITOR’S NOTE: Additional recalls have occurred since the publication of this article, and the total number of recalled batteries has now topped 7.5 million.)
Despite these high-profile recalls, the hazard potential shouldn't be exaggerated. For example, Dell recalled millions of battery packs because of six incidents reported since December 2006.
Of course, nobody wants to be one of the unlucky few, and you're probably wondering what the hubbub is about. This week I'll answer questions about the risks of lithium ion batteries. Next week I'll offer tips on what you can do to protect yourself, plus give you an update on what's being done to reduce or eliminate such risks in the future.
Why Would a Battery Overheat?
Most portable electronics today, such as notebooks, cell phones, and MP3 players, are powered by lithium ion batteries. Compared to the earlier generation of nickel metal hydride batteries, lithium ion batteries have a better power-to-weight ratio, hold a charge longer, have a longer usable life, are lighter, and don't have the "memory effect," which can cause a battery that's regularly "topped off" to prematurely fail. Lithium ion batteries are also inexpensive to manufacture.
The downside: Lithium ion batteries contain an electrolyte (lithium salt) dissolved in a highly flammable solvent. If the batteries short-circuit, they could overheat--causing failure, and sometimes making them erupt in flames.

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