The much-hyped Galaxy Note 7, which was touted to be Samsungâ€™s flagship phone has been in the news lately for its repeated explosions, caused by problems of battery overheating. A string of such incidents from Note 7 users, has been reported from different parts of the world.
So, what causes smartphones to overheat?
It is natural for smartphones to generate some amount of heat because any activity that is performed inside the phone is based on movement and movement produces heat. But if you are performing a power-hungry activity like playing a graphics intensive game, it means there is more load on the processor and the graphics processing unit (GPU), which are both located in a central system-on-a-chip (SoC), and this causes more electricity to be generated which in turn leads to more heat.
SoCs are generally well optimized and are designed to handle high temperatures. However, if your device is frequently overheating, hardware overloading could be the reason. Use of excessive apps, multitasking and simultaneous use of Wi-Fi, Bluetooth draws a lot of the processing power. This warms the battery due to increased flow of electricity.
The phone could also heat up if it is left in the open under direct sunlight or due to a hardware malfunction.
Some other reasons which can cause your phone to overheat include viruses/malware, camera activities that involve a lot of video recording, an insulated phone case that traps the heat within and a faulty battery or charger.
How does the heat affect the battery?
Most of todayâ€™s smartphones come with a lithium-ion (Li-ion) battery. The important thing to understand here is that Li-ion batteries are rechargeable which means that the chemical reaction which generates electricity happens in both directions i.e. electrons leave the battery to travel through a circuit and back. Hence, the transfer of charge happens multiple times.
The two major drawbacks of Li-ion batteries are that they are highly sensitive to heat and they also degrade over time. Hence, where the ambient temperatures are high, the phone will tend to heat up when the battery is charging. In extreme cases, this can lead to an explosion.
What can be done to avoid overheating?
Batteries should not be charged up to 100 per cent as this causes the battery to be exposed to more heat. Also, it is important that you do not run your battery down to zero charge. Ideally you should charge your battery from 30 per cent to 80 per cent which helps prolong the battery life.
Operating a smartphone while it is plugged in and charging should be strictly avoided since it places a lot of stress on the battery.
In general, avoid multitasking, refrain from graphics-intensive activities like playing demanding games and use Bluetooth for short periods.
If all else fails, it is time to replace the battery or change the phone altogether as it could be defective.