Toshiba has offered to exchange 340,000 notebook computer batteries, but said they do not pose a fire hazard. Instead, defective batteries could unexpectedly cut power to the notebooks, causing users to lose unsaved work. The batteries, made by Sony, may fail to charge correctly, causing the power to cut off suddenly if the notebook is not connected to a main outlet, said Toshiba spokesman Keisuke Ohmori.Reports of lithium ion cells in notebook batteries overheating or catching fire have prompted other computer manufacturers, including Apple Computer and Dell, to issue safety recalls. Dell recalled 4.1 million batteries used in its notebook computers in August, citing a fire hazard, while Apple recalled 1.8 million batteries, warning that they could overheat.Toshiba\u2019s batteries are not at risk of starting a fire, Ohmori said. "There is no such hazardous or related issue," he said. Instead, Toshiba\u2019s problems stem from a defect in the interface circuitry between the battery cells and the computer.That defect is caused by corrosion, said a spokesman for Sony, the manufacturer of the batteries. An ingredient used in the insulating paper of batteries manufactured between March and May can corrode components in the batteries\u2019 charging circuits, causing them to fail, said Sony spokesman Takashia Uehara. The supplier changed the composition of the insulating paper without notice, he said. Batteries made for other notebook manufacturers also contained the paper, and Sony is working with those companies to see whether there is a problem, Uehara said. He declined to say how many batteries were affected overall.Toshiba\u2019s battery exchange offer covers 10 models of Toshiba notebook computer. The company will post a software tool to its website shortly, allowing customers to identify whether their computer is affected, Ohmori said.In related news, both Virgin Atlantic Airways, a U.K.-based airline, and South Korea\u2019s Korean Air responded to the Dell and Apple battery recalls by banning the use of\u00a0certain battery-powered laptops aboard flights.\n\n-Peter Sayer, IDG News Service (Paris Bureau)(Al Sacco, CIO news writer, contributed to this report.)\n\nRelated Links:\n\nDell to Recall 4.1M Batteries Due to Fire Hazard\n\nApple to Recall 1.8M Laptop Batteries\n\nApple, Dell Plot Battery Standards\n\nKorean Air Bars In-Flight Use of Apple, Dell Laptops\n\nVirgin Atlantic Adds Apple, Dell Laptop RestricitionCheck out our CIO News Alerts and Tech Informer pages for more updated news coverage.