Myths and truths: What is the right way to charge your cell phone?

Who has never lived the moment when the cell phone no longer holds the charge for a whole day? The end of the useful life of the battery is a reality, but there are ways to to prevent ensure that this component wears out quickly.

To help you understand the best ways to charge devices, Angelo Sebastião Zanini, coordinator of the Computer Engineering course at Instituto Mauá, explained what is best to do when charging your cell phone.

How does a battery work?

Currently, they are made of lithium, a material that allows the manufacture of batteries with a high capacity even with a small size. To make it work, the charger moves the ions from the negative to the positive pole of the battery, just like the principle of every cell.

Zanini explains that “When you use the battery, the flow is opposite. The charges go from the positive pole to the negative pole and cause this circulation of charges to power the device, making it work.”

Is it recommended to let the battery reach 0% to charge?

This cell phone component has a defined number of complete cycles until the end of its useful life. However, by carrying out smaller loads, instead of letting it reach 0%, it is possible to increase the battery life. “It is not recommended that you do this, but rather partial loads”, said the professor.

Are fake chargers reliable?

The answer is no. Because they are poorly designed, they may not pass sufficient voltage, damaging the battery. The risk is that they heat it up, charge it inappropriately and shorten the useful life of this part of the cell phone.

Does leaving it charge overnight affect the functioning of the cell phone?

Properly designed chargers with a safety system are not dangerous as they stop supplying energy when charging is complete. “However, this does not always happen. Sometimes there are multiple cycles of small charges and discharges, which means that the battery is always powered,” said Zanini.

Therefore, the recommendation is not to leave your cell phone charging overnight. Ideally, this should be done during the day and, preferably, in airy places so that the device does not heat up.

Can you unplug the device without charging it completely?

Yes! As lithium batteries do not need, as we said, to reach 0% to charge properly, there is no problem in unplugging the cell phone before reaching 100%.

Is charging your cell phone on the computer bad for the battery?

As with inadequate chargers, the USB cable does not always have the ideal charge to transfer energy correctly. Although high-power USB exists, this is not the standard, so it is not recommended.

Do fast chargers shorten the lifespan of the device?

There are cell phones in which the components are adapted for these types of chargers, which generally come with the device. However, Professor Angelo Zanini suggests some precautions with this type of charging: “A higher current can heat the battery during the charging process and heating a lithium battery is a bad situation that can damage or shorten the battery's useful life. .”

And he adds: “Observe whether the fast charger is heating the battery too much. If so, it is recommended not to use it.”

Is using your cell phone while charging harmful to the battery?

No, but it is also not recommended. The danger, in this case, is for whoever is using the device, and not for the component. If an electrical discharge or lightning affects the energy current being passed to the device, it can pose some type of danger to whoever holds the cell phone. Furthermore, the hand is a heat source that changes the ideal temperature of the battery.

Is changing batteries when their capacity is reduced safe?

“Undoubtedly! Whenever it has a very slow charge and discharge cycle or no longer 'holding' the charge, you can change the battery”, explained Zanini.

It is important to remember that this material must be disposed of in appropriate locations so as not to damage the environment and to recycle lithium, which is a high-value material.