Sony has promised to share the cost of a massive battery recall announced by Dell on Monday after a series of laptops burst into flames.
Dell reported to the US Consumer Product Safety Commission that 4.1 million laptops worldwide could catch fire, and recalled the batteries, which were built by Sony.
Asked if Sony would help pay for the cost of the action, a spokesman said: "We are supporting Dell in many factors of this recall and that is one of them."
The financial impact on both companies is unclear. Sony would not say how much money was involved, but did say it had also provided the battery cells to other PC manufacturers.
The defect was caused by a short circuit that happens when microscopic metal particles break through the lithium-ion cell wall and contact a battery anode, said Sony spokesman Rick Clancy.
"You try to eliminate that in the manufacturing process, but to eliminate them 100 percent is very difficult. Usually when you have a short circuit, it might lead to a battery powering down so you'd have a dead battery, but other times it could lead to incidents including flaming," Clancy said
The chances of a short circuit depend on the design of each PC, such as whether the battery cells are aligned in parallel or perpendicular, and their proximity to heat sources like the processor and power supply. But ultimately, the odds are against the engineers, since any given particle can create a short, just as any given sperm can make a baby.
"It's kind of like impregnating someone. It only takes one, so the more of them there are, the more likely it is that you'll impregnate someone," said Clancy.
Despite the challenge of blocking every particle, the number of short circuits has been very low, Sony insists.
"It's a number you can count on two hands," Clancy said. He added that it is inconsequential "when you look at it by Six Sigma standards". Six Sigma is a measure of engineering quality that ensures a process will not produce more than 3.4 defects per million opportunities.