Battery calibration must be real

[Galacticos]

My friend who has an iPhone 6 heard about calibration just the other day so he decided to drain his battery to do it for the first time.

On full brightness and volume he played a video and his phone remained on 1% for 75mins!!

If I remember correctly on 11.1.2.

I know Apple say iOS works it out but after seeing this, it just doesnt

 

[casperes1996]

Right... So the thing is that iOS keeps pretty good track of this stuff, and under normal usage scenarios it should be fairly accurate for a really long time. However, some charging behaviours will indeed make the system a bit confused, especially over longer periods of time. Draining your battery entirely is really something lithium-ion batteries hate however, so I can't really recommend a full drain, at least not very often at all.

 

[Galacticos]

Right... So the thing is that iOS keeps pretty good track of this stuff, and under normal usage scenarios it should be fairly accurate for a really long time. However, some charging behaviours will indeed make the system a bit confused, especially over longer periods of time. Draining your battery entirely is really something lithium-ion batteries hate however, so I can't really recommend a full drain, at least not very often at all.

Yeah I avoid going below 20%, and depending on how fast the battery is being used, as it is now, will often get a charge at 50 or 60 so I can last the rest of the day.

All that said I wonder if a fresh install would recalibrate in a ‘safer’ way. No evidence for or against that though

 

[casperes1996]

All that said I wonder if a fresh install would recalibrate in a ‘safer’ way. No evidence for or against that though

That wouldn't make sense really. The reason the battery "needed" calibration didn't have to do with iOS itself, but the firmware on the battery, and even if you could load a new firmware onto the battery, it'd need to get maximum and minimum values for battery charges by achieving maximum and minimum charges first, which'd mean a classic calibration.
iOS just shows the battery percentage it gets from the battery firmware. Any optimisations Apple may do in this field isn't done in iOS per se, but the battery management chips and firmware. Of course iOS can be coded to take certain steps when it gets information from the firmware, but the percentage shown, and the reason you might calibrate, has nothing to do with iOS itself

 

[C DM]

My friend who has an iPhone 6 heard about calibration just the other day so he decided to drain his battery to do it for the first time.

On full brightness and volume he played a video and his phone remained on 1% for 75mins!!

If I remember correctly on 11.1.2.

I know Apple say iOS works it out but after seeing this, it just doesnt

It's not really the battery that's being calibrated, but more the meter that estimates the battery percentage based on voltage and some other measurements.

 

[Galacticos]

It's not really the battery that's being calibrated, but more the meter that estimates the battery percentage based on voltage and some other measurements.

Yeah

 

[Julien]

It is NOT really battery calibration but battery charger (yes the charger is inside and NOT what you plug into the wall) calibration. The circuits can get out of calibration with what is in the battery and give a false reading.

 

[lexvo]

Draining your battery entirely is really something lithium-ion batteries hate however, so I can't really recommend a full drain, at least not very often at all.

Yes, full drain is not good for Li-ion batteries, but I understand that Apple prevents a complete drain by shutting the iPhone off (so even if it says 1% there actually might be a little more power left). Every now and then I drain my battery fully and recharge it to 100% to calibrate. I have done this for years with several devices without any problem.

 

[RPB65]

I have calibrated mine when I feel it needs it. I use the phone how I like and over 2 years on my 6S+, the only thing that has negatively affected my battery has been rogue code in some of the public beta software or a poor install of it, somehow messing it up. I'm still going to get a new battery though under the cheap renewal offer from Apple.

 

[casperes1996]

Yes, full drain is not good for Li-ion batteries, but I understand that Apple prevents a complete drain by shutting the iPhone off (so even if it says 1% there actually might be a little more power left). Every now and then I drain my battery fully and recharge it to 100% to calibrate. I have done this for years with several devices without any problem.

This is indeed true - but it still gets low enough that it's detrimental to long term sustainability. Not necessarily a big enough problem that the increased accuracy of your meter isn't worth the benefit, but it will still have a negative impact on the battery's lifetime. But it's not something to go mental about if it runs dry of juice.