When can your mobile battery burst?

The world's largest mobile manufacturer Samsung has had to stop production of its smartphone Note 7. The company says that it has taken this decision, taking matters related to maintaining quality and safety seriously. On August 19, the news of this smartphone launched in the market during or after charging started to come out after a week. The situation became so severe that many countries prohibited the use of this phone during air travel.

Looking at the incidents of battery burst, Samsung withdrew about 2.5 million Note 7 smartphones from around the world. But even after this, the problem of heating in the mobiles which were given back to the customers remained the same. Many customers in the US complained of smoke coming out of the replaced Note 7 smartphone. After this, the company temporarily stopped the production of Note 7. The company says that it will lose about three billion dollars i.e. about 20 thousand crore rupees from this whole episode.

Theoretically, companies have achieved about 90 percent of the maximum battery life of a lithium-ion battery. But even after this, efforts are on to get more battery life.

There have been incidents of mobile battery burst earlier, but the ruckus on them has happened for the first time. According to experts, one reason for this is that Note 7 is the flagship phone of the company, which costs more than 60 thousand rupees, and the class that uses this phone and its likes and dislikes are very important for the mobile companies. It is being said that this shock to Samsung may prove to be an opportunity for its rivals like Apple and Google.

But how did it miss a reputed company like Samsung? In an interview, scientist Linden Archer of Cornell University of America says that in today's time there is a race among mobile companies to give new features to their mobiles. Because of this, mobile companies have a chance to get even a little bit better than before. Archer explains that theoretically, the maximum battery life that a lithium-ion battery can have is about 90 percent of the companies have achieved. But even after this, efforts are on to get more battery life. According to Archer, new features are added to expensive smartphones first, so their chances of problems in their batteries are increased.

How does the battery work?

Before knowing why the lithium ion battery used in the smartphone bursts, it is very important to know how this battery works. Lithium is used in mobile batteries because it is very light and can store more energy. This battery consists of two electrodes. There are ions with positive charge on one, called cathode. It is filled with lithium. The second electrode is called the anode on which there are ions with negative charge.

When the mobile is charged, lithium ions start moving from the cathode to the anode and when the battery is being discharged, these ions move back from the anode to the cathode. Between these two electrodes there is a mixture of chemical substances called electrolytes. The electrolyte makes the current flow by making the transfer of ions between the cathode and the anode easy. The thing to keep in mind is that the cathode and anode should never meet each other during this time. To keep them away, a wall or separator is placed in between them.

On behalf of Samsung, it has been said that due to the two electrodes joining together, there are incidents of smoke coming out of the battery and bursting. According to officials, the cathode and anode have merged due to problems in the separator between the electrodes in the batteries of some mobile sets.

According to experts, the combination of cathode and anode is considered to be the worst situation for any battery. When these two electrodes meet, all the energy comes out of them and goes into the electrolyte. The heat starts increasing in such a battery and the electrolyte is not so stable and strong that it can handle this situation. At higher temperatures, the chemical of the electrolyte starts to react with other chemicals available in the battery. As a result, such gases are formed which further increase the heat of the battery. These reactions occur repeatedly and the temperature of the battery increases rapidly. This sequence is called 'thermal runway' in chemistry, which ends with a fire or explosion in the battery. However, sometimes in this situation some mobiles are shut down or even shutdown instead of bursting.

There are many situations in which the cathode and anode can meet or the battery may burst?

Mobile overcharging The problem of mobile over charging comes when the battery is left on for several hours of charging. In this case, excess lithium ions reach the anode from the cathode. In an interview, scientist Dan Stengart at Princeton University says that mobile batteries can be understood by the example of a rubber band. Charging the battery is like pulling the rubber band and when the battery is in use it is like the rubber band coming back to its position. The way the rubber breaks when it is over-stretched, in the same way, overcharging can cause the battery to burst due to the excess lithium ions collected on one side.

However, Dan also says that most mobile batteries also have the facility to protect them from over-charging, in which the battery automatically stops charging when full charged. But, in recent times, problems have also been found in this system. For this reason, many experts also advise never to charge the battery hundred percent.

Fast charging

Recently, many mobile companies have also given the facility of fast and quick charging of the battery in their smartphones or its chargers. In this way more energy is stored in the battery in less time. Knowledgeable about battery technology considers this facility too dangerous. They say that there is a problem of 'plating' in the battery. According to them, both electrodes (cathode and anode) are like egg crates. At the time of charging, lithium ions have to be arranged in the grooves in the crate of the anode like eggs.

When the battery is comfortably charged, ions coming from the cathode have enough time to settle in these grooves of the anode. However, when fast charging occurs, these ions come to the anode rapidly and in a large number, due to which they are not properly arranged in the crates of the anode. In this case, most of the ions collect outside the egg crate and then form a needle-like structure on top of each other. This structure is called dendrite which causes a short circuit like problem inside the battery.

health and fitness blog

When can your mobile battery burst?