Sony Electronics Corp. has announced further increase in the number of rechargeable lithium-ion batteries to be replaced worldwide, as it has reportedly confirmed reports about Sony Vaio battery replacement plan.

Japanese Nihon Keizai Shimbun news-paper reported early on Monday that Sony may recall up to 300 thousand of its batteries used in its own Vaio notebooks. When back in August it transpired that batteries containing Sony-made cells could overheat, catch fire or explode, Sony said that its own Vaio notebooks were not affected. Now, however, the company needs to replace batteries on laptops sold in China and Japan. According to Reuters news-agency, Sony has confirmed either 60 thousand or 90 thousand of batteries it plans to replace and also said that it might revise its earnings forecasts.

“We are in the process of determining whether a revision to our annual earnings outlook is necessary, taking into account various factors that could affect our group earnings,”the electronics and entertainment conglomerate is reported to have said.

Sony said in an official statement that the recall arises because, on rare occasions, microscopic metal particles in the recalled battery cells may come into contact with other parts of the battery cell, leading to a short circuit within the cell. Typically, a battery pack will simply power off when a cell short circuit occurs. However, under certain rare conditions, an internal short circuit may lead to cell overheating and potentially flames, the company indicated. The potential for this to occur can be affected by variations in the system configurations found in different notebook computers.

Back in August Apple and Dell have recalled combined 5.9 million – 1.8 and 4.1 million respectively – batteries for notebooks after several incidents, in which batteries produced by Sony flamed and/or exploded. In mid-September Toshiba said to replace 340 thousand of laptop batteries also made by Sony, as those could run out of power unexpectedly. Hitachi and Panasonic said they would recall batteries for 16 thousand and 6 thousand of their laptop batteries that contained Sony-made cells respectively. Finally, Toshiba said it would recall 838 thousand batteries for its notebooks, Lenovo announced plans to replace 526 thousand rechargeable lithium-ion batteries that include cells supplied by Sony and Dell said would recall 100 thousand more batteries, increasing its total numbers of accumulators to be recalled to 4.2 million. In addition, Fujitsu said it would replace 287 thousand of batteries for its notebooks.

To date, the total amount of Sony-made rechargeable lithium-ion batteries to be recalled is over 8 million of units.