iPhone X Strange "Battery Health"-behaviour

[flyproductions]

6 weeks ago, after 5 years of use, i replaced the battery of my iPhone X as it was down to 78% health after somewhat over 1000 charge cycles.

Battery of choice was a Dejimax 3500 mAh which works perfectly fine so far. Great battery life! Better than ever before. Somehow as expected, according to the 3500. Also as expected, "Battery Health" in the settings was showing 100%.

But recently all of a sudden it switched back to the old battery's 78%! Performance did not change in any way. And the more trustworthy way of checking the "real" battery health, using the analytics data, as well as coconutBattery keep showing something slightly below 3500 with a very narrow degradation over the 50 cycles the battery went trough since in operation. So everything works perfect and the issue seems to be plain cosmetic.

But i just wonder where the settings get this old battery's value from (if not from the analytics data!). I tried resetting to factory, which did not change anything: Battery settings keep showing 78%, service state with the usual "your battery's..." statement above. Anybody ever experienced similar? Not that it would influence the use in any way. But if i knew a way to reset it to the "real" value, i would like to.

 

[scsskid]

i guess its a bug since 3rd replacement batteries dont show health at all in ios settings

its probably the last value which the system read off you old battery

 

[JPack]

Aftermarket BMS board can be iffy. Unless you swapped out the BMS, you can’t rely on the % or any Coconut readings as those rely on BMS.

 

[flyproductions]

Aftermarket BMS board can be iffy.

Didn't this all start with Xs?

Unless you swapped out the BMS, you can’t rely on the % or any Coconut readings as those rely on BMS.

What Coconut or the analytics files show seems to make perfect sense and corresponds to the usage experience / battery life after a full charge. Problem is, that it completely differs to what is shown in the battery settings. This shows the 78% of the old battery, while working condition is better than new.

 

[flyproductions]

i guess its a bug since 3rd replacement batteries dont show health at all in ios settings

its probably the last value which the system read off you old battery

Strange thing is, that it first showed 100% for 5 weeks and then suddenly switched to 78.

 

[JPack]

Didn't this all start with Xs?

What Coconut or the analytics files show seems to make perfect sense and corresponds to the usage experience / battery life after a full charge. Problem is, that it completely differs to what is shown in the battery settings. This shows the 78% of the old battery, while working condition is better than new.

It started from day one. The original BMS is a TI chip and unless the manufacturer uses an original or does a swap, it may not be accurate.

 

[flyproductions]

It started from day one.

Yes, but i never heard of anybody swapping the board with a battery replacement before the iPhone Xs.

And wouldn't it be even more likely to see the old battery's health value if the board would have been swapped (but not reset)?

 

[JPack]

Yes, but i never heard of anybodx swapping the board wit a battery replacement before the iPhone Xs.

And wouldn't it be even more likely to see the old battery's health value if the board would have been swapped (but not reset)?

Apple didn't start encrypting the chip until Xs. Back then, all anybody cared about was seeing 100% capacity after a battery replacement. Aftermarket chips/batteries all did that, but the accuracy of the reading after that was always questionable.

If the BMS is swapped, either it gets reprogrammed or the newer method is to attach a tag on flex cable.

 

[flyproductions]

Apple didn't start encrypting the chip until Xs. Back then, all anybody cared about was seeing 100% capacity after a battery replacement. Aftermarket chips/batteries all did that, but the accuracy of the reading after that was always questionable.

Yes! But, aside of the "encryption", i really don't know why the BMS of the old battery should be any "better" than the one, the new one comes with. They might even come from the same manufacturer.

If the BMS is swapped, either it gets reprogrammed...

So why swapping and reprogramming the BMS of anything older than Xs, when the new battery has one allready reset on it?

And further on, if Coconut as well as the analytics files get their values (which make perfect sense!) from the new BMS, but they differ largely from what the settings show (which is obviously fake!), how could swapping the BMS have cured that?

Sure one should take care of not buying some chinese trash programmed to show some fake 5000mAh for a iPhone X battery. But there sure are well made aftermarket parts by reputable factories far better than the original...almost six years later.