ROUND ROCK, Texas (AP) -- Dell Inc., the world's largest personal computer maker, said Friday that it is increasing the recall of Sony Corp. battery packs used in its systems to 4.2 million units from 4.1 million units.
The batteries can short-circuit and have been blamed for causing some computers in which they are used to overheat.
Separately, Toshiba Corp. said Friday that it is recalling 830,000 batteries made by Sony for its laptops at Sony's request. It was the latest in a growing global recall involving Sony batteries, bringing the tally of recalled batteries to about 7 million worldwide.
Earlier Friday, Sony asked manufacturers using its problem batteries to carry out a recall.
Toshiba spokesman Keisuke Omori said Toshiba's recall was in response to Sony's request, and Toshiba had not found any cases in which the laptops were at risk of catching fire.
"But we wanted to assure and satisfy our customers," he said.
Dell said Friday that the increase in its battery recall was made due to additional information received about the affected battery packs containing cells manufactured by Sony.
Dell and the Consumer Product Safety Commission announced the agency's largest-ever electronics recall on Aug. 15, blaming battery cells supplied by Sony. During production in Japan, tiny shards of metal were left in the cells, which can cause a short-circuit. The recall was issued after six confirmed instances of overheating or fire involving Dell systems with batteries made by Sony.