Five Myths About Smartphone Batteries Explained
In just a few years, the batteries in our smartphones have changed a lot. This means that these old tips for extending battery life are not as true as they once were, but we still share them as if they were the gospel. Before telling someone to turn off Bluetooth or Wi-Fi, let’s shed some light on these old myths.
Myth: the battery must be completely discharged before plugging in.
Batteries used to be blunt. Old batteries will “forget” their full capacity, so they cannot be fully charged again. Thus, you will have to let the battery fully discharge to 0% before charging it again. This is no longer the case, and it was not so long ago.
Smartphones today have lithium-ion batteries , which do not suffer from the memory problems of old nickel-cadmium and nickel-metal hydride batteries. Likewise, lithium-ion batteries count charges differently than older batteries, so you don’t have to worry about completely discharging them. This is how Apple explains it , and while they refer to their batteries, the rules apply to any lithium-ion battery:
Charge your Apple Li-ion battery anytime. There is no need to let it fully discharge before recharging. Apple lithium-ion batteries operate in cycles. You complete one charge cycle when you have used up (discharged) an amount equal to 100% of your battery’s capacity, but not necessarily all in one charge. For example, you can use 75% of the battery capacity one day and then fully charge it overnight. If you use 25% the next day, you will discharge a total of 100%, and in two days you will have a total of one charge. It may take several days for the cycle to complete. The capacity of any type of battery will decrease after a certain amount of recharging. For lithium-ion batteries, the capacity decreases slightly with each complete charge cycle. Apple Li-Ion batteries are designed to retain at least 80% of their original capacity over multiple charges, which vary by product.
Most manufacturers still ask you to “calibrate” your battery by discharging and recharging it every one to three months. As the overall life of your battery decreases over time, the time remaining for each full charge decreases slightly with each full discharge. Basically, each discharge will shorten the battery life slightly. Discharging to 0% once a month helps the operating system calibrate the full battery life so it knows exactly how much it has decreased over time.
However , more and more batteries have a digital calibration tool built in. These “smart batteries” supposedly reduce the need for calibration, although it’s still recommended when your battery is behaving strangely. If you see that your phone’s battery percentage fluctuates a lot (for example, you could swear it was fully charged and now it is 20%), it’s time to calibrate it. However, you shouldn’t do this too often. It’s really bad for lithium-ion batteries to discharge to 0% regularly. This is considered a complete charge cycle, which in turn shortens the overall battery life.
Myth: Charging the battery overnight will shorten battery life.
Just like calibrating a battery, it used to be possible to ruin a battery by “recharging” or leaving it plugged in at all times. When you plug your phone into the mains for an extended period of time, old lithium-ion batteries can overheat (or explode, in rare cases), which in turn simply reduces the charge capacity and long battery life (this can still happen if you have a cover that prevents heat dissipation).
Chargers and smartphones are smart enough these days to prevent this from happening. Speaking with iFixit tech writer Andrew Goldberg, Popular Mechanics said the following :
What is not a problem is the overpricing. Contrary to what you might think (or have been told), leaving your phone or laptop plugged in at all times is not bad for its battery. This is because your gadgets, the batteries in them, and the chargers you plug them in are actually quite smart and business-friendly. Drip charging – what your battery gets when it’s plugged in and fully charged – is far less damaging to the health of your battery than draining too much.
However, keeping your phone connected to the network all the time may result in poor performance, but it’s not enough for you to even notice. As we pointed out earlier , if you want to extend the battery life, you have to keep it within 40-80% at all times. It sounds great on paper, but for a person living in the modern world, it’s pretty ridiculous. The good news is that leaving it on overnight while you sleep, even if it’s almost fully charged, doesn’t have the same negative effect on it as it used to.
It’s also a good time to point out that caring for your smartphone battery is a bit different from caring for a laptop-like battery for one simple reason: you’ll probably buy a new phone at least once every two years. The life cycle of this battery is not as important as it used to be because the lifespan of the phone is very short. Sure, you might be the type to hold your phone forever, but if you don’t, you don’t need to worry about it. No matter what you do, batteries drain and degrade over time, so don’t get too hung up on it.
Myth: Closing apps will increase battery life.
We like to think of our smartphones as small computers, and we treat them the same way. On your laptop, opening many applications at the same time, especially those that connect to the Internet, puts a lot of stress on your battery, so it makes sense that your smartphone will work the same way, right? Wrong. That’s not how smartphones work.
In the case of iOS, apps don’t stay open the same way they do on a computer. When you leave the application, it freezes, does nothing, and does not require any resources. Closing them doesn’t do anything for your battery power except it costs a powerful processor and battery to keep everyone close . Former Genius Bar Technician Scottie Loveless explains :
When you close an application, you retrieve it from the phone’s RAM. While you might think this might be what you want to do, it is not. The next time you open the same app the next time you need it, your device will load it into memory again. All this loading and unloading puts more strain on your device than just leaving it alone. Plus, iOS automatically closes apps as it needs more storage, so you do what your device is already doing for you. You should be a user of your device, not a cleaner.
It’s the same with Android. Some people claim that task killers work with closed applications and increase battery life. The problem is, they don’t work and do more harm than good . And while some apps might close if you remove them from the multitasking drawer, many won’t – it’s all about the way the app was written.
Instead of constantly closing apps, it’s best to turn off features that drain your battery, such as notifications or background data calls. On iOS, this is called “Background App Refresh”. This means that applications can download data in the background even if they are out of focus. When they do this, they are using up the power of the processor, which drains the battery. You can prevent apps from doing this by going to Settings> General> Background App Refresh and changing the switch for all apps you don’t need. On Android, you can turn off background data by going to Settings> Wireless & networks> Data usage and set Allow background data to Restrict background data. However, keep in mind that while this will save you battery power, some apps, like the Play Store, simply won’t work at all with limited background data.
All of this does not mean that the problem is not with the applications. Certain software, such as messaging apps, completely ruins your smartphone’s battery life . So, turn off background app refresh for apps that don’t need it, turn off notifications for apps that don’t have a business to notify you, and uninstall any apps you don’t actually use. Apps can still kill your battery if they’re poorly programmed or just very demanding. Smartphones have great metrics now, so you can keep track of which apps are doing it. On Android, you can go to Settings> Battery to see which apps are using the most power. On iOS, go to Settings> Battery to view similar information.
Myth: Only “Official” Chargers Should Be Used with Your Phone
Smartphone manufacturers want you to use the official charger that came with your phone. Look at any box or manual and they often say it is “highly recommended” not to use another charger. However, while you shouldn’t use cheap, sketchy knockoffs or fake chargers , available third-party chargers are fine .
Modern USB chargers are standardized, and while you will see different results on charging times with different chargers, this will not affect the battery itself in any way. Ken Shirriff studied various chargers a few years ago and found that while the time it takes to charge a device varies from charger to charger, doing it with a third-party charger does not affect the battery itself. This includes using chargers that supply a different number of amps than the phone expects. Modern smartphone batteries are smart enough to only use the maximum amount of power they can handle, no matter what is supplied, so there is no danger of overheating as long as the charger itself delivers the correct current. Fake chargers often claim to supply more (or less) power than they should (or change a lot even during a charging session), which is where the problem comes in. Third party chargers do not.
Myth: Turning off Bluetooth, Wi-Fi, and geolocation significantly saves battery power.
It seems that every new feature added to smartphones, whether it’s a background app update on iOS or Google Now On Tap on Android , poses a major threat to your smartphone’s battery life. While that’s true, you don’t have to go through and toggle every new feature to the Off position, and there’s no point in turning off basic system services like Bluetooth or Wi-Fi just to conserve battery power.
For example, MacWorld analyzed how toll services consume iPhone battery and found that many of them had little effect. For example, leaving location services for an app you’re not actively using has little to no impact on battery life. Likewise, turning on airplane mode, which turns off cellular, Wi-Fi, Bluetooth, GPS, and location services, only squeezed out an extra 30 minutes of life, which isn’t all that much, all things considered (and that was two years ago, with the situation has probably improved since then).
Wi-Fi and Bluetooth used to consume a lot of power, but now they use so little that turning them on and off has little effect on battery life. As far as location services go, let the apps that need to use it, but make sure you don’t have apps that use your location all the time for no particular reason. This constant use still kills your battery, but luckily, you usually have the option to restrict location services to only active ones when the app is open. Of course, if you’re not using Bluetooth or Wi-Fi, just leave them disabled, but don’t feel like you should .
What usually kills the battery the fastest is the screen. So if you’re really worried about battery life, just turn off your screen and put your phone in your pocket until you need it.