One of the report in the early days, was the fact that a Dell laptop left on idling for 7 hours and it started a fire.

Not mentioned was whether power supply was used along with the Sony battery or not?

Then more fires were reported on all laptops, but no distinguishing of cpus used in the laptops? Or how long the laptops were used?

Sony batteries are lithium formulated. Lithium will start an explosion or a fire by impact, or heated up beyond the safety factor.

So, the battery could heat up if the circuit shorted out, causing an overheating of the battery. Normal charging of lithium batteries will heat up. Quick charging of lithium batteries will need fan cooling to be safe.

So, where are we today to safe guide the laptop users with Lithium battery?

Latest report from IBM, Research triangle, NC. revealed that the metal particles used in the lithium ion batteries made by Sony to increase current capacity can short out the battery itself and cause a fire, before the battery can be shut off.

In my year of research on recharging all kinds of batteries; NiMH and Carbon Zinc batteries do have similar behavior of shorts or partial shorts in the battery equivalent circuit.