Monday, 19 September 2016

Three Reasons of Lithium-ion Battery of Fire or Explosion

One of the main power supply computers and other portable electronic products. However, lithium-ion battery charging and discharging process because of improper use can be dangerous and explosion; especially under abuse conditions (such as heat, overcharge, short circuit, vibration, compression, etc.), the battery will be a fire, explosion or even staff injuries and so on. Therefore, the study of the explosion mechanism of lithium-ion batteries to improve the safety of lithium-ion batteries has important significance.



Lithium-ion battery fire or explosion three possibilities, with the following three.

First, when the lithium-ion battery to heat, the reaction inside the battery, such as a chain reaction, each reaction and promote each other, in turn. First, the SEI film decomposition exothermic heating battery, prompting a negative reaction to the solvent release more heat, resulting in a negative reaction with a binder, and solvent decomposition, then followed by the positive terminal of a thermal decomposition reaction and emit a lot of heat and gas and finally cause the battery to fire or explosion.

Second, at the beginning of rechargeable lithium-ion battery, the battery current through a portion of the electrical energy into heat energy, ohmic polarization also generates some heat, but the battery surface temperature rise is very slow; when the battery reaches full charge, lithium ions continue embedding the reaction of lithium metal becomes deposited on the surface of the negative electrode, the solvent is oxidized (by the over-charging due to solvent exothermic heat of the oxidation reaction is much higher than the state of the lithium ion reversibly exothermic heat of reaction with the solvent) heated by the heat of the discharged battery; as the battery temperature increases, the reaction solvent and lithium metal, lithium is reacted with carbon solvent have occurred, thermal runaway, accompanied by the occurrence of decomposition of the solvent, the reaction with lithium metal binder.

Third, the harm short circuit, acupuncture and the impact caused by lithium-ion battery is approximately the same. When the short-circuit current generated by the instantaneous battery a lot of heat, heat the battery, the battery temperature rises to the decomposition temperature of the positive electrode, the cathode thermal decomposition and cause the battery thermal runaway; when acupuncture is fast, resulting in a partial puncture site short circuit and generates a lot of heat, the temperature inside the battery rises to the positive thermal decomposition temperature; when the lithium-ion battery by the impact, over-voltage electrode generating heat loss, prompting a negative reaction with the solvent, the heat released further heating battery to promote the positive thermal decomposition reaction occurred heat runaway.
One of the main power supply computers and other portable electronic products. However, lithium-ion battery charging and discharging process because of improper use can be dangerous and explosion; especially under abuse conditions (such as heat, overcharge, short circuit, vibration, compression, etc.), the battery will be a fire, explosion or even staff injuries and so on. Therefore, the study of the explosion mechanism of lithium-ion batteries to improve the safety of lithium-ion batteries has important significance.

This article comes from http://www.storagebattery-factory.com/news/three-reasons-of-lithium-ion-battery-of-fire-or-explosion.html.

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