BitDepth 540 - September 05

"That's a hot laptop," he said. And then it burst into flame...
Exploding laptop batteries

At a Japanese conference in June, the battery in a Dell laptop burst into flame. Photos courtesy The Inquirer.

Batteries, the power source behind most of the technology devices we take for granted, betrayed a potentially dangerous Achilles heel over the last few weeks.
Dell and Apple both announced massive recalls of Sony-made batteries across a range of their laptop lines. The battery recall came after weeks of reports on Internet news sites of laptop batteries bursting into flame.

In April, Nick Brown, 11, heard a popping sound coming from his Apple iBook laptop and found the room where he left the computer filled with smoke. The family got the laptop out of the house, where a sequence of photos show the laptop engulfed in flames before it melted into the patio.
In another widely circulated Internet report in June, laptop users at a conference in Japan are captured in a grainy camera phone image recoiling from a Dell laptop on a table aglow with flame.

A reader for the Internet website The Inquirer identified as "Gaston" reported "the damn thing was on fire and produced several explosions for more than five minutes."
In March, the Guidant Corporation issued a warning to doctors of problems with batteries in its Contak Renewal 3 RF and Renewal 4 RF cardiac defibrillators
The company announced "39 reports of lower-than-expected battery voltage" in the devices, which manage errant heart rhythms. According to Guidant, none of the devices were implanted into patients. Guidant did not elaborate on the source of the batteries.
Soon after media outlets began picking up the growing number of reports of overheating batteries, Dell announced a major recall of Sony made batteries installed across the company's laptop line. More than four million batteries sold with Dell Latitude, Inspiron, XPS and Dell Precision Mobile Workstation notebook computers are considered to be at "risk of fire."

Dell has created a special website at <
www.dellbatteryprogram.com> which lists the serial numbers of the affected batteries and links to an online serial number checker into which Dell owners can enter the serial numbers imprinted on their battery.
Within a week, Apple followed suit with its own recall, affecting 1.8 million batteries and set up its own site that Mac laptop users can reference to check whether their batteries are affected at .
Dell and Apple have recalled batteries on a much smaller scale in 2004 and 2005, but those recalls covered 300,000 batteries. This recall will cost Sony as much as US$250 million.

Potential fallout
Airlines may become skittish about batteries in laptops, although the actual incidence of exploding batteries is miniscule relative to the number of potentially affected computer systems. Investigations into the crash of a cargo flight in February suggest that lithium-ion batteries being shipped on the plane may have caught fire.

What makes Lithium so dangerous?
The need to pack more energy into ever smaller spaces has led to ever more volatile chemical reactions being packaged into batteries. Lithium is a potentially explosive alkali metal which reacts forcefully with water.

The compounds used in batteries are less volatile than pure lithium and rechargeable lithium batteries are said to be less prone to explosive discharge than their non-rechargeable kin. In Sony's press release on the recall it noted that "on rare occasions, microscopic metal particles in the recalled battery cells may come into contact with other parts of the battery cell, leading to a short circuit within the cell."

Standard fire suppression procedure for handling these kinds of chemical fires is to remove all flammable materials from the proximity of the fire and leave it to burn itself out. Lithium will extract oxygen from water and continue to burn.

What should you do?
If you believe that an Apple or Dell laptop you own may be affected, check the relevant website to compare the serial number on your laptop's battery with the ranges specified by the manufacturer. You can confirm a potential match by using the web applications built into the sites to establish an exact match.

Apple and Dell appear to be working on an advance shipping model for the recall. The companies send a replacement battery to affected customers, who must send the defective battery back after receiving the replacement. You should remove a positively identified battery immediately from the laptop and run the computer on its AC power adapter.
If you have a laptop that isn't part of the recall, you should periodically check your battery for signs of overheating (most will run warm during use) and examine the battery's casing for the bulging and deformations that are a telltale sign of the cell swelling that's one indicator of runaway battery reactions.

Links
<
www.dellbatteryprogram.com/>
<
support.apple.com/ibook_powerbook/batteryexchange/index.html>
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