Sony said Thursday that the number of laptop batteries to be recalled would total 9.6 million worldwide.
Sony Corp.'s defective lithium ion battery packs have caused massive recalls, with nearly every major laptop computer maker to ask customers to return their batteries subject to replacement.
The recalls come after the discovery that the batteries can short-circuit and cause some computers to overheat or even burst into flames. Previously, Sony had not provided a figure of how many batteries would be subject to recall.
Thursday's estimate comes hours after the company slashed its fiscal year profit forecasts due to the massive global battery recalls and price cuts in Japan for the next-generation PlayStation 3 video game console.
The Japanese electronics maker now expects group net profit of 80 billion yen ($673 million) for the fiscal year through March, down 38 percent from the 130 billion yen ($1.1 billion) it had forecast in July.
It said that in the July-September period it will rack up an extra cost of 51 billion yen ($429 million) for recalls of lithium-ion batteries for laptops announced by practically every major laptop maker in the world.
Sony-made batteries have been recalled in recent weeks by U.S. makers Dell Inc. and Apple Computer Inc., as well as Japanese makers Toshiba Corp., Hitachi Ltd., Fujitsu and Sharp Corp. whose laptops also use Sony batteries.
Sony is joining the recall with its own Vaio laptops and that will also trim earnings for the current fiscal year, Sony said.
The estimated total of 9.6 million batteries include the latest recalls of 90,000 batteries in Vaio, Sony said.