iPhone 8/Plus Is Apple's battery health accurate?

[Ffosse]

I ask this as I have an iPhone 8 which I've had since last September, very light use and it's battery is showing as 98% of full capacity. Fair enough, I think, that sounds about right.

But my X which I bought in January has been used very heavily - I would estimate at least 4 times as much as the 8 and it still shows 100% capacity. I've been unable to use the coconut app utility with either phone as it doesn't recognise them (probably something I haven't clicked in settings, and it's too much of a faff connecting the usb-c of my MacBook to either phone to try again, ie. I'm too lazy.

 

[Newtons Apple]

My X also shows 100%, purchased in November. Not sure of the accuracy but do know that Apple has it's own battery diagnostic app. I tend to not worry about my battery as I replace my phone yearly.

 

[akash.nu]

Any battery meter is always an estimation. You can’t measure chemical reactions with minute accuracy with the type of softwares we have at this point. In the lab under a microscope is a different thing altogether.

 

[now i see it]

As akash mentioned, there's no direct way to accurately measure li-ion battery state of charge or battery wear. These two metrics can only be estimated by calculations based on a few known variables. It's definitely not an exact science.

As for the wear level percentage displayed in iOS 11, this too is an estimation based on a calculation. One part of the equation uses the specification of the battery when new... not the actual battery capacity. If the battery comes out of the battery factory with a higher capacity than the spec, iOS 11 doesn't know this. It only uses the specification in the calculation. That's why some iPhone X batteries still have an apparent %100 capacity even after 8 months. Its not because the battery hasn't degraded, (because it has) it just that iOS 11 thinks there's a smaller capacity battery installed than what actually did get installed.

 

[itsmilo]

don’t think so. It shows 96% health on my very old iPhone 6 yet it says 88% for my 7 Plus

 

[Minorite]

If you can't use Coconut check it with iMazing, results are pretty accurate.

 

[stexie]

I think it only gives your approx indication / estimation but far from accurate.

I've own iphone 8 plus for only 1 month and the meter already indicates my battery health is at 98%. Ironically my iphone 6 plus (4 year old) is still showing 89%. How is that possible.

 

[Newtons Apple]

I lost faith in the battery app after my X still shows 100% after a year.

 

[BugeyeSTI]

It’s usually a few percent different than coconut battery so I’d say not really..

 

[cableguy84]

Had my 8 plus less than 2 months , has dropped to 97% already. Not one bit bothered.
Will probably only have the phone 2-3 years, will let the next owner worry about the battery.