Cause of incident?
What is actually supposed to have happened? Spontaneous combustion of a lithium-based battery? If that can happen, shouldn't we ban all lithium-based batteries (laptops, tablets, phones ...) because of the danger of spontaneous combustion? If it wasn't spontaneous combustion, then what was the cause and how do we prevent that and other causes from setting off lithium-based batteries, in card readers or other devices?