6 truths about the life of your phone battery: Overcharging, overheating, fast charging - CNET

We asked battery experts what a fast charger does to our phone's battery over time and how to extend your battery's life.

Whether you have a new iPhone SE, Samsung Galaxy A51 or OnePlus 8, your phone's battery life is an increasingly important factor in deciding if your device is worth the money.

But now that fast charging is so readily available for phones, we have questions: Can a high-capacity charger damage your phone's battery in the short term.

To get the answers, we spoke with several battery researchers and engineers about the effects of quick charging on your phone's battery life.

Instead, much of the recent progress in battery life has come from power-saving features built into devices and from making the software that manages charging and discharging more efficiently, so you sip power rather than guzzle it. .

Unfortunately for mobile phones, the focus on extending battery life is generally on cars, satellites and your home's power system, areas where industrial batteries need to function far beyond the two or three years we expect from our mobile devices.

To avoid this stress, electric car makers may charge new batteries just to 80%.

Larger phone batteries can give you an all-day run time from a charge, but typically only at the full 100%.

Short of a major breakthrough in battery technology, improvements to our phone batteries will come from making  the devices more energy-thrifty overall.

Unless there's some technical flaw with your battery or charger electronics, however, using a fast charger won't do your phone's battery any long-term damage.

That's because during the first phase of charging, batteries can absorb a charge quickly without major negative effects on their long-term health. .

That last part is the second charging phase, where phone-makers have to slow down and carefully manage the charging speed or else the charge process actually could damage the battery.

For a battery, this unabsorbed charge can result in shorts and other issues that could potentially damage the battery.

A battery's management system closely monitors the two charge phases and drops the charging speed during the second phase to give the battery time to absorb the charge and avoid issues, which is why it can take 10 minutes to get those last few percentage points. .

The fear was that keeping a phone constantly plugged in could charge a battery beyond its capacity, making the battery unstable, which could degrade overall battery life or build up too much internal heat and cause the battery to burst or catch fire. .

iOS 13 can help reduce the strain of charging up your phone.

If you frequently keep your iPhone plugged in during the day or while you sleep, you can turn on an iOS 13 battery setting called Optimized Battery Charging that will monitor your charging schedule and hold your iPhone's battery charge at 80%, keeping it out of the stress zone.

At one time, you may have wanted to let your phone discharge all the way down once in a while to help the battery recalibrate its state of charge.

In fact, discharging a battery all the way down can cause chemical reactions that over time can shorten a battery's life.

You'll want to keep your phone out of strong sun, away from window sills and off the dashboard of your car to prevent overheating, which can make the battery less efficient over time.

Some phones, such as those from Huawei and OnePlus, use a proprietary charging design -- with part of the circuitry responsible for rapid charging built into the charger