For a long time, you always carry a time bomb without realizing it

Although their actual explosion rate is very small, but with billions of devices in use today, the number may be larger than one can imagine.

This can frighten you, but you are carrying a time bomb in your lap, or in your wallet or in your back pocket. If you have an electronic device that uses a rechargeable battery , it will most likely be a Lithium battery . This means that when you give your baby a phone, you're throwing them a time bomb.

Of course, the ability of the device to actually explode is very small . "The ratio is only about 1 in 1 million." Ken Boyce, a battery expert and technical director at UL, told Gizmodo. However, Boyce added that there are now billions of Lithium batteries in the world. After two decades of improvement by engineers and materials scientists, supported by safety science experts like UL, helped create batteries with almost absolute safety. However, the natural properties of Lithium batteries also mean they are always capable of exploding at any time.

The ability of the device to actually explode is very small.

Back in 1995, the year Apple launched the Powerbook 5300, the first product to use Lithium batteries in the world. But when the Powerbook 5300 caught fire and had to be recalled, it cost the company millions of dollars and tech experts started talking about the end of the Lithium battery. Fortunately, this technology has been continuously improved until now, so when Apple batteries were swollen (and occasionally burned) in 2007, it only caused a silent recall.

That's why the current failure of Samsung Note 7 is so noticeable. After a lot of explosions, the Note 7 is forced to conduct a global recall. It is also banned by many airlines, and US officials have told people to turn off the phone and stop using it permanently.

It certainly wasn't the first phone to explode, but with the advancement of new technologies, along with the characteristics of battery technology, Samsung unfortunately became the center of a fire storm of criticism.

Indeed, the main reason for batteries exploding is not new. Long temperature is the enemy of Lithium batteries. The temperature reduces the battery's ability to hold power, which is why your phone will run out of battery faster between the heat of summer or when you use it for too long. And for a few rare cases, it may also overheat. It is time for battery heat to escape.

Long temperature is the enemy of Lithium batteries.

" Heat is the technical term for describing the universal limit of explosion, " Professor Yang Shao-Horn, an energy professor at MIT, told Gizmodo. "It's not really an explosion, it's just catching fire." Heat loss is a chemical reaction that occurs when the temperature rises exponentially - causing chemicals to heat up quickly, and like lithium batteries, they are also very flammable.

Lithium batteries are no different from a mixture of flammable chemicals compressed together and exposed to an electric current through electrodes. There are two main electrodes in a Lithium battery, anode (anode) and cathode (cathode). The energy comes in from the anode and escapes from the cathode, and the two parts are separated by a layer of organic salt- containing organic material - an excellent element for storing and transporting energy.

If the cathode and anode are in contact with each other, it will cause heat loss. Lithium batteries were first encased in fragile pockets, which were easily punctured, causing the anode and cathode to touch each other, leading to the battery being damaged. But the following batteries have avoided that.

So what is the possible cause of the Note 7?

Lithium batteries caught fire when punctured.

In the video above, you can see a standard Lithium Ion battery (18650) similar to a battery in a Vape or in a battery block on a Tesla Model S. As soon as the cover of the battery is punctured, extreme sound and anode touch each other, heat escape will occur. However, the ability to explode due to this puncture can be significantly reduced thanks to better battery production - this is why you don't need to worry about the Tesla Model S burning to charcoal after one. car collision.

From Samsung's reports, the burning of the Note 7 has something similar to the example of a punctured cover above. An error in the production of some Note 7 batteries may have caused the batteries to be over-compressed , thus increasing the likelihood that the cathodes and anodes will come into contact.

According to Professor Shao-Horn, this is a reasonable conclusion. But she did not rule out another cause that is also likely to cause heat loss: that is overcharging. When the battery's positive electrode becomes so flexible that it begins to produce oxygen inside, damaging the balance of the chemical mixture sealed in the battery pack, and leading to heat release.

Image of a Vape burning in the user's pocket.

"These processes can happen even in a perfect battery," said Shao-Horn. Errors in the battery manufacturing process on the Note 7 are also related to some explosions of cheap vape.

And they are not just processes. Even a poor quality USB cable can be harmful to your device. The process of charging a complicated phone or laptop or vape, and the batteries we are using, are potentially dangerous - a real time bomb if not used properly. That's why the FAA always reminds you to take Lithium batteries into the cabin when flying. In this way, if they catch fire and catch fire, people can react faster.

It is the danger from the fire caused by Lithium batteries that is why Apple has to quietly replace laptop batteries that have been swollen nearly 10 years ago, and why Samsung, despite heavy losses in cash, still is replacing the damaged Note 7 batteries.