As reported by WCCO, a Lithium Ion battery in an Apple iBook G4 overheated and caught fire as an 11 year old left it unattended for a few moments in a families' home. The burning laptop once discovered was rushed out the back patio, where it continued to spew out flames and fire. This WCCO television report documents the occurrence, and although it's a little hyped up in the reporting, the issue of exploding batteries and battery packs catching fire is a serious one.
Apple has since recalled several different models of Li-ion batteries, as have Dell. Some 12-inch Apple iBook G4, 12-inch Apple PowerBook G4, or 15-inch Apple PowerBook G4 notebooks are included in the current recall. The Apple Web site will tell you if your laptop is included, but the gist of it is: "The recalled batteries include those with model numbers A1061, A1078, and A1079 and serial numbers that begin with HQ441 through HQ507 and 3X446 through 3X510. These batteries were manufactured by LG Chem, Ltd. of South Korea. "
In another example of the exploding laptop issue, the Inquirer reports that a Dell allegedly exploded at a conference in Japan, presumably after its Li-ion battery overheated and burst. "An inquirer reader attending a conference in Japan was sat just feet away from a laptop computer that suddenly exploded into flames, in what could have been a deadly accident. Gaston, our astonished reader reports: "The damn thing was on fire and produced several explosions for more than five minutes"."