Table 6.

Ignition source and its temperature

	Definition	Ignition source		TIgnition source
				°C
Forced ignition	The CEG is heated locally by forced ignitions, and the local CEG ignites first, and then, the flame spreads to the others. Forced ignition sources often have high temperatures.	Spark	(1) Electric spark caused by too small electric clearance between conductive parts	3000–6000
			(2) Electric arc caused by lots of sparks	8700–9700
			(3) Static electric spark caused by invalid equipotential bonding	–
			(4) Mechanical spark caused by friction between the eruption flow and the wall	~1200
			(5) Spark from the ICE pipe	600–800
		Hot spot	6) High temperature surface of the cell	~1000
			(7) High temperature cable with short circuit or overcurrent	–
			(8) Cigarette butts	250–800
		Flame	(9) Gas flame	1600–2100
			(10) Gasoline flame	~1200
			(11) Match flame	500–650
Autoignition	The CEG is heated whole by autoignition sources and then ignites. The autoignition source does not need to have a high temperature but needs to have enough energy to heat the CEG.	Self-heating	(1) Heats from the chemical reactions during the generating process of CEGs	200–1000
			(2) Heats from slow chemical reactions of CEGs caused by lighting, catalytic reactions by cathode materials, etc.	–
		Non-self-heating	(3) Heats from high temperature autoignition sources often with indirect contact with the CEG, such as the high temperature surface of a cell with thermal runaway, the high temperature surface of the ICE of another vehicle, a heater, etc. They can make the temperature of all the CEG be increased.	–
			(4) An energy source that converts other forms of energy into heat, such as friction, compression, etc.	–