Sony faces an unprecedented potential loss of more than $225m after notebook PC batteries it supplied to Dell apparently exploded or caught fire, industry sources have revealed to vnunet.com. 

Analysts have calculated that, in a worst case scenario under which Sony pays to replace all 4.1 million batteries in the affected notebooks, the Japanese company might lose more than $225m.

Dell announced yesterday that it would repair or replace 4.1 million notebook batteries that contain cells manufactured by Sony. 

The computer maker warned customers to stop using the batteries immediately because they could overheat or even start fires. The move follows a small number of recent reports of notebook batteries bursting violently into flames.

Users of Dell Latitude, Inspiron and Precision notebooks are urged to visit a special Dell Battery Recall website. 

Based on the information available to date, analysts at Nomura Securities in Japan have speculated about the maximum potential cost to Sony if the company is determined to be at fault. 

"If Sony were to shoulder all costs related to the supply of replacements - the worst scenario for Sony - we estimate that the cost would total around ¥26bn [around $225m]," Nomura predicted in a private research briefing for its investment banking clients.

The analysts stressed that this approximate figure is a "probable worst case scenario", and is necessarily based on several assumptions about the average battery costs due to limited information available from Dell and Sony.