No matter what you do, your phone's battery capacity — which translates to its lifespan — will degrade as you use it.
I hate to be the bearer of bad news, but you might be reducing your phone battery's lifespan with certain charging behaviors.
Specifically, if you often charge your phone overnight or keep it plugged in for hours after it's reached 100%, you're accelerating the aging process of lithium-ion smartphone batteries.
"If you're going to charge your phone to 100% and keep it at 100% — just keep on charging and charging overnight — this will have negative influence on aging," Dominik Schulte, the managing director of the German battery-technology consultancy firm BatterieIngenieure, told Business Insider.
Indeed, as a lithium-ion battery ages, the chemistry within changes and becomes less efficient at storing and delivering power to your device.
To be sure, all lithium-ion batteries age and have a limited lifespan. No matter what you do, your phone's battery capacity — which translates to its lifespan — will degrade as you use it. But you can have a say in how quickly your smartphone battery ages.
Meanwhile, the companies behind the smartphones in your hands and pockets don't seem overly concerned about you letting your phone charge for too long.
I've asked smartphone companies what they think about charging phones overnight and keeping them at 100% for hours on end. Most referred me to informational webpages on their respective smartphone batteries.
In short, the company that made your smartphone doesn't seem to think that charging your phone overnight is cause for much concern.
Apple does mention overnight charging on one of its informational pages but doesn't say it's not a good idea to do so.
Google said that worrying about overcharging your phone is an "outdated" concern.
Ronald Ho, a product manager at Google, told Business Insider that "in general, this mentality that 'overcharging is bad' or 'charging too often is bad' is pretty outdated given the current battery and charging optimizing technologies companies can build into their devices."
Ho said that "when the phone's battery reaches 100%, the phone's internal battery charger will actually stop charging to prevent overcharging." Phone batteries will get a top-up from a charger only when they reach a certain level under 100%
But Schulte and most smartphone makers agree on one thing:
When you store a smartphone you don't plan to use, you should keep the battery charge within a certain range — and that's a hint that smartphone batteries don't like being at 100%.
Schulte said that lithium-ion batteries age slowest at about 30% to 50%. And that's about the range where most smartphone makers suggest you keep your phone's battery charge when you plan on storing it away for a while.
On its battery webpage, Samsung says you should keep its battery charge at "at least 50%." Apple says to keep the iPhone "half-charged when it's stored for the long term" to "help extend battery lifespan."
At the end of the day, lithium-ion batteries don't like being at 100%, at least for long periods.
But no one is suggesting that you only ever keep your smartphone between 30% and 50%.
That's simply unrealistic for a device that most of us keep by our side all day, especially when we often need it to last a long time between charges.
The key is to not store or keep your phone's battery at a 100% charge for extended periods.
Instead, Schulte said that "it would be very good to charge the phone in the morning or whenever, but don't store the phone overnight at 100%."
It could all come down to how often you buy new smartphones.
It's hard to say how quickly overnight charging actually accelerates the aging process of the lithium-ion batteries in our smartphones. It may not produce any noticeable effects if you buy a new phone every year, or maybe even every two years.
But if you typically buy a new phone because yours is dying too quickly — and isn't that old — you might want to reevaluate how you've been charging your phones. An overnight charge might not be considered such a long time, but the damage could build up the longer you keep your smartphone. If you're an overnight charger and plan to keep your phone for several years, it might be time to ditch that behavior.
But remember, all lithium-ion batteries die. You can be the most cautious phone charger in the world and your phone's battery life will still degrade, albeit slower.
There are a couple of other things that almost everyone agrees on about smartphone batteries.
For one, avoid fully discharging your smartphone before you charge it again. And avoid extreme temperatures whenever possible.
But in the end, smartphone batteries are meant to be used, so don't worry too much about it.
All in all, don't stress. If you can charge your phone in the morning instead of overnight, great. It can be worthwhile to see whether changing your charging habit can have a positive effect on your phone battery's lifespan.
But if not, you'll be fine.
Perhaps the best thing to know is that many phone makers give you the option to replace your battery for a fraction of the price of buying a new model.