Hewlett-Packard Japan Ltd. said Thursday it will replace battery packs used in dozens of its laptop computers for free because they might overheat and catch fire.

The recall affects 39 models, including 21 not sold in Japan. Domestically, the recall will cover about 5,500 computers with built-in batteries made between August 2007 and May 2008, the Japanese unit of Hewlett-Packard Co. of the United States said.

Although burns and other accidents have been reported abroad, none has been reported in Japan, HP Japan said.

The company has been voluntarily recalling the batteries since last May. It expanded the move this time to cover more models and units.