The two types of batteries commonly used to power consumer PEDs (Personal Electronic Devices) brought on aircraft are lithium batteries (disposable) and lithium-ion batteries (rechargeable).  Both these types are capable of ignition and subsequent explosion due to overheating. Overheating results in thermal runaway, which can cause the release of either molten burning lithium or a flammable electrolyte. Based on testing by the Fire Safety Branch of the Federal Aviation Administration (FAA) William J. Hughes Technical Center, the following procedures are recommended for fighting a fire of a lithium-type-battery powered PED.  The procedures consist of two phases: extinguish the fire; cool the remaining cells to stop thermal runaway. Utilize a halon extinguisher or water to extinguish the fire and prevent its spread to additional flammable materials. After extinguishing the fire, douse the device with water to cool the device and prevent additional battery cells from reaching thermal runaway.