If you have a new iPhone (iPhone 8, 8 Plus, or the much hyped iPhone X), battery problems are the last thing on your mind. But for those with older iPhones, it’s probably top of mind—especially after Apple admitted to secretly slowing down batteries and is now offering $29 replacements until Dec. 31, 2018.
Battery slowdowns on aging phones are nothing new; lithium-ion batteries are the best option we have for mobile tech today, but they’re far from perfect. The more power cycles they go through, the worse their capacity gets.
Apple’s “fix” is why many people with older iPhones report battery problems whenever a new version of iOS comes out. It’s not just that iOS is written for new devices and runs slower on old models (though that’s certainly part of it). It’s that Apple, in its infinite wisdom, actually cripples older phones in the name of “overall performance and prolonging the life of…devices.”
It’s maddening. But Apple got caught when some older iPhones improved after new batteries were installed and people went public with it on Reddit. Weeks later, the company is being sued, and the battery replacement is its public relations response.
The $29 battery replacement only applies to iPhone SE, 6, 6 Plus, 6s, 6s Plus, 7, and 7 Plus. Older phones have to be covered by AppleCare or the battery replacement still costs $79—except if the battery is less than 80 percent capacity when fully charged, in which case the AppleCare battery swap is free.
To get your new battery, take an iPhone to the Apple Store’s Genius Bar or mail it in. But what if you’re on the fence about your own iPhone’s battery? How do you tell if its capacity is low and it’s gone through 500 charge cycles—Apple’s somewhat arbitrary number for what it considers the lifespan of an iPhone battery?
In other words: how do you tell if you need a replacement battery?
Check Wear With an App
The easiest thing to do is download an app like Battery Life (there are multiple apps with that name, but this version, by RBT Digital, seems to be the most robust).
The first thing the app will do is display a giant front page graph showing battery wear level. Here are three versions you can compare. The first one is on a 2-year-old iPhone 6s Plus; the second is a smaller iPhone 6s purchased a year ago; the third is an iPhone X that’s barely a week old.
Wear level is the battery’s capacity to hold a charge compared to its capacity when brand new. For example, an iPhone X comes with a battery (the X actually has two batteries inside) with a total capacity of 2,716 milliamps per hour (mAh); according to the Battery Life app, it still has that full capacity. However, the iPhone 6s Plus has a battery that was originally capable of 2,725 mAh, but now can only hold 2,300 mAh, or 84 percent of what it once could handle.
The more you check this app, the more history it keeps, so you can check to see as your iPhone battery capacity decreases over time. That happens after more and more charge cycles are used.
A charge cycle happens every time you discharge 100 percent of a battery’s capacity. That doesn’t have to be all the way down to 0. If you keep your phone charged to 80 percent, then use it down to 30 percent, and do that twice in a day—using that 50 percent twice is a full charge cycle.
Apple says its batteries are good for 400 to 500 charge cycles. That usually takes a year or two—or around the time you’d upgrade iOS and see it all slow down when the new iOS detects an aging battery and reduces processor output to “help” you. It doesn’t hurt that Apple would also prefer you purchase a new phone around that time, too.
No app lets you see how many charge cycles you’ve used on an iPhone. (Unless you jailbreak your iPhone.) Maybe that’ll change in 2018. Apple is promising an iOS upgrade that will “give users more visibility into the health of their iPhone’s battery, so they can see for themselves if its condition is affecting performance.” Until then, the only way to actually check the charge cycle usage of an iPhone is with…a computer.
Check Charge Cycles on a PC
It might seem counterintuitive to require a laptop or desktop PC to check how many times you’ve used a charge cycle on your iPhone’s battery, but alas, those are Apple’s rules.
Previously, whenever developers tried to release an app that measured iPhone battery charge cycles, Apple pulled it from the App Store. With iOS 10, Apple then pulled info on charge cycles as well as battery temperatures so third-party apps like Battery Life could not get to them. Let’s hear it for transparency!
However, there are some desktop programs to get you through.
On a Mac, download coconutBattery, which will also tell you all about the health of your Mac’s battery.
Plug your iPhone into the Mac via the USB-to-Lightning cable, then turn on coconutBattery to get a reading on the iOS Device tab. Under the charge capacity graphs, you’ll see a listing that says “Cycle Count” so you can tell how far you are from that dreaded 500. If you pay to get coconutBattery Plus for $9.95, you can monitor all this info over Wi-Fi on your Mac without plugging the iPhone in via USB.
It works on iPads as well but iPads aren’t getting slowed down by iOS, even if they’re older.
Windows users should turn to iBackupBot; it works on Windows 7, 8, and 10 and costs $35 after a 7-day free trial. It’s ostensibly for backing up all sorts of info off an iOS device to your PC, but when you plug in an iPhone to the PC and run iBackupBot and build a phone profile, you can also access a section called More Information that clearly shows a “CycleCount” under the battery section (as well as the original DesignCapacity and current FullChargeCapacity of the battery.)
HowToGeek reports that you can also contact Apple via their support website, give them remote control of your iPhone, and they’ll reveal the battery’s health (albeit without specific numbers). Whether you trust that from the company that just admitted to crippling CPUs just because batteries get old is up to you.
When Should I Get a New iPhone Battery?
Now that you’re armed with the info needed to measure capacity and even charge cycles, you’ve got to decide when to get that new battery.
Here’s what I’d suggest: if you’ve got anything older than an iPhone 7, get the $29 battery change next time you’re anywhere near an Apple Store. It’s the cost of a few venti hot chocolates, and worth it to give those older iPhones another year of decent performance.
If you’ve got an iPhone 7 or newer, check the Battery Life app infrequently and see where things are headed. If your iPhone battery is headed to just 80 percent then look into the replacement options stat, hopefully before Apple’s battery deal runs out at the end of the year. (Remember, if you have AppleCare and your battery goes below 80 percent capacity, they’ll replace it free, or maybe give you a replacement iPhone equivalent if anything else has gone awry.)
Or, buy the battery replacement kit from iFixit and do it yourself. It also costs $29, but will be available after Dec. 31. And it works on older iPhones, but not iPhone 8, 8 Plus, or X. The downside is you have to open the iPhone up yourself.