Is overcharging of mobile battery real ?

[Frenemy90210]

I think max. voltage of a mobile battery is 4.3 V and voltage of a USB charger is 5 V; My question is , if we keep the charging process on even after mobile battery is 100 % charged, is it true that it will damage the battery ? Does it reduce the life of a battery or does it reduce the charge holding capacity ?

 

[chroot]

Hey Frenemy90210,

Some older types of batteries could indeed be damaged by keeping them connected to a high voltage even after they had reached 100% charge. Some older batteries would simply lose capacity. It was even possible for a battery's electrolyte to decompose, causing gases to be generated. The gases could physically damage the structure of the battery, and make it deform or explode.

The answer is very different for modern battery systems -- the kind you would charge over USB. Modern battery systems have intelligent charging circuitry built directly into the battery cells, and there are microcontrollers in both the charger and device that constantly monitor the charging process. These systems are really smart! You can leave a USB charger connected to your device indefinitely with no risk.

It is true that batteries experience the greatest stress when they are hot, and when they are fully charged. You can keep your battery healthy for more charge cycles if you keep it cool and don't leave it 100% charged all the time. This effect is fairly small, though -- you might get 650 charge cycles instead of 600.

My best advice? Charge your device whenever it is convenient, and don't worry about it. The batteries and chargers were designed for that kind of use.