Maximize Battery Life

Expected Longevity

Current batteries in consumer electronics don’t last forever. Their lifespans may increase with each new generation  of device and this is due to the efficiency of the rest of the hardware and software. Generally, though, there’s a limit to the number of times they can discharge and recharge. As they reach their limits, their total capacity decreases and this can degrade overall device performance as well.

Modern Mac laptop batteries (since around 2010) have a limit of 1,000 charge cycles. As Apple explains, a charge cycle is the discharge and recharge of a battery’s capacity, no matter how you break it up. One percent discharge matched to one percent recharge maps to one percent of one charge cycle. Do the math.

You don’t have to do the math. Open System Information (go to the Apple menu and hold the Option key for a shortcut), go to the Power section, and look for Cycle Count under Health Information.

iPhone batteries are rated for 500 cycles and iPads for 1,000; both expect to retain 80 percent of their designed capacity at that point and will experience significant declines in performance or longevity if not replaced. Use coconutBattery on your Mac to see the cycle count of a connected iOS device.

For battery replacement in the San Francisco East Bay, unless your device is under warranty, I highly recommend Joe iPhone Unlock & Repair Services for iPhones and Apple & Mac Solutions for Macs. For iPads, I think you can’t beat Apple’s flat fee of $99–149 (depending on iPad model).

iPhone & iPad Tips

As I described last fall in Mac Mondays: Application Switcher, quitting apps from the app switcher will not reduce battery usage. In fact, it may cause an increase depending on how you use your device, because you’ll force it to reload apps from scratch instead of loading them from memory.

With that out of the way, start with updating your software to the latest version supported. Modern devices are extremely efficient and well integrated, and updates generally offer improvements.

However, iOS offers offer a variety of ways to conserve battery during use. If you need to eke out more time between charges, try reducing background activity (Background App Refresh), decreasing display brightness, or using Low Power Mode (where supported).

Mac Tips

Unlike iOS, running Mac applications does use more energy as macOS enables them to operate simultaneously. Quit apps you’re not using to save power. Also, your Mac will automatically reduce display brightness when switching to battery and you can dim it further to conserve.

Meanwhile, like iOS, update your software when feasible (following the advice of your local guru to postpone macOS upgrades as appropriate).

I’ve also heard that MacBook batteries may offer increased lifespan when kept between 20% and 80% charge. However, my practice continues to be to plug in my MacBook when an outlet is conveniently available and run on battery otherwise. [Update: As of 2023, the latest MacBook models support specifying a maximum charge in order to optimize the battery’s lifespan.]