What the Tech? Myths about iPhone batteries
Are you charging your smartphone all wrong? Over the past ten years there have been many false statements and beliefs making their way across the internet concerning some correlation between when and how often we charge our phone, to how long that battery will last.
I'm here to dispel some of those myths with the help of Apple. I'll be primarily talking about the iPhone battery but you can certainly apply these to other devices because they all use similar Lithium-ion batteries. You've probably heard of these myths and may live your life (and your battery's life) according to what you've read or heard from a friend. The next few paragraphs are intended to set the record straight. These come from Apple and Apple engineers.
Myth #1: Force quitting apps you are not using by swiping them off the screen, will increase battery life between charges. This one is false according to some Apple software engineers. When you close an app by moving on to something else on your phone, the app slides to the background. Logical thought suggests it is still using power because it's in the background. In truth, apps that are in the background are not running and do not use any power. In reality, force-closing an app by swiping may use slightly more battery life because when you re-open an app from scratch it uses more power than it would if the app was open in the background.
Myth #2: Leaving a phone on charge overnight will damage the battery and shorten its life. This one is also false. Lithium-ion batteries cannot be 'overcharged' meaning they do not take in more current than is needed. So when the phone reaches 100% charge, it stops charging. Simple as that. So it's perfectly fine to put your phone on charge before you go to sleep and unplug it the next morning.
Myth #3: A battery's life-span is determined by how many times it's been charged. This one is true. According to Apple, an iPhone battery chemically ages and the amount of charge they can hold diminishes. A normal battery is designed to retail up to 80% of its original capacity at 500 complete charge cycles. In other words, after about a year and a half (if you charge your phone every night) the battery doesn't hold as much of the charge as it did when it was new. One charge cycle is when it is discharged an amount that equals 100% of the battery's capacity.
If you use 20% of the battery before 9am, then charge it completely and use another 40% in the afternoon, that's a total of 60%. A cycle is the total amount of power that is used.
Learn about iPhone charge cycles here.