Over the past decade, rechargeable lithium batteries have become ubiquitous, powering our phones, computers and even some cars.
But they also have the risk of a strong fire, which is a special safety issue when a large number of batteries are shipped on the plane. Why lithium?
Ion batteries are more dangerous than other batteries?
Lithium batteries are popular because they encapsulate more energy in a small package.
However, their chemical properties make them easier to catch fire under certain conditions because, unlike other rechargeable batteries, they contain flammable electrolyte and remain pressurized.
What is the cause of battery fire?
If the battery has manufacturing defects, damage, too tight packaging, excessive charging or exposure to excessive temperatures, they may overheat, resulting in a situation called "heat out of control.
"In this case, an increase in temperature will lead to a continuous further increase in temperature --
An uncontrolled positive feedback.
If a battery is overheated, it will cause other nearby batteries to overheat and experience heat out of control.
Flammable electrolyte can also be ignited.
Why is it difficult to put out a lithium battery fire? Li-
At the fire temperature of the battery, it has been measured up to 1,100 degrees Fahrenheit, close to the melting point of aluminum used in the aircraft structure.
It is possible to extinguish the flame of the battery fire with water, but water does not stop the heat from getting out of control, so the flame often comes back.
The halogen lamp fire extinguishing system on the aircraft should be able to extinguish li-
The battery is on fire, but the flame may return after the halogen gas is exhausted.
The gas emitted by the overheated battery can also cause an explosion that can disable the suppression system.
What did you do about this?
International Civil Aviation Organization, United States of AmericaN.
The agency that sets international safety standards agreed last year to ban the transportation of lithium batteries on passenger aircraft and to require batteries on cargo aircraft to be charged no more than 30%.
The authorities hope that reducing the energy in the battery will reduce the risk they take on their own. ignite.
The new rules apply only to international flights.
If countries wish to extend these rules to domestic flights, they must adopt them.
Battery manufacturers oppose the new regulations, saying the risk is exaggerated and that the demand will disrupt the supply chain.