"We have determined that there is no possibility that any battery trouble could cause smoking or fire in our notebook computers," said a Fujitsu spokesman. "Most Japanese makers don't allow high voltage to flow from their AC adapters to the computer battery, out of safety concerns."
Fujitsu statement follows, saying batteries made by Sony could smoke and catch fire.
Fujitsu, Toshiba and Hewlett-Packard use Sony lithium-ion battery packs but the batteries used are different from those shipped to Dell, the companies said.
Sony shares have been under fire on concerns that the recallin the face of fierce competition from rivals Samsung Electronics and Sharp.
Sony is still assessing the possible financial impact of the recall, including replacement, shipping, storage and personnel costs, a Sony spokesman said.
He added that nothing had been decided on whether Sony would pay for all the recall costs involved.
U.S. consumer safety officials said on Tuesday they were reviewing all Sony-made lithium-ion batteries in laptop computers for fire hazards. The Japanese electronics company holds a 25 percent global market share in lithium-ion batteries for notebook computers, after Sanyo Electric.
Sony has said the overheating problem is believed to be specific to batteries supplied to Dell and that an incompatibility between the battery cells and Dell's recharge system was to blame.
Apple Computer and Lenovo Group also use Sony batteries.
"Our management software makes sure no such overheating occurs, and we are confident that the computers are safe," said a spokesman from Lenovo Japan.
In early trading Thursday, Sony shares were up 13 cents, to $45.19, on the New York Stock Exchange.