Analysis of the type of lithium battery explosion
The type of battery core explosion can be classified into three types: external short circuit, internal short circuit and overcharge. The outer part of this system refers to the external surface of the core, which includes short circuit caused by poor insulation design inside the battery pack.
When the electric core is short circuited and the electronic component fails to cut off the circuit, the inner core will produce high heat, which causes the vaporization of some electrolyte and the battery shell. When the internal temperature of the battery is high to 135 degrees centigrade, the fine diaphragm will close the hole, the electrochemical reaction terminates or nearly terminates, the current drops and the temperature drops slowly, thus avoiding the explosion. However, the closing rate of the hole is too bad, or the diaphragm that is not closed at all, will keep the battery temperature rising, more electrolyte vaporized, finally the battery shell broken, even the temperature of the battery to make the material burning and explosion internal short circuit mainly because the copper foil and aluminum foil Pierce the diaphragm, or lithium. The dendritic crystals of the atom break through the diaphragm. These tiny needled metals can cause short circuit. Because the needle is very thin and has a certain resistance value, the current will not be very large.
The burr of copper foil is caused by the production process. It can be observed that the battery leakage is too fast, most of which can be screened by the electric core plant or the assembly plant. Moreover, because the burr is fine, sometimes it will be burned, so that the battery will return to normal. Therefore, the probability of burglings caused by short circuit burr is not high.