2 iPhone 12’s here. 5m old. Both MagSafe charge since day one. Both batteries 100%.
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iPhone 12 mini Abnormal Battery Health Decline?
- Thread starter Channan
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2 iPhone 12’s here. 5m old. Both MagSafe charge since day one. Both batteries 100%.
I had a weird one. Bought a new iPhone 8 in August 2020, sealed in the package. By June 2021 the battery health had dropped to 92% but Apple battery health software came up with the 'battery service' message which I didn't expect would happen until battery health was around 78%.
I didn't bother trying to get to the bottom of it my mother needed a replacement for her aging Samsung and only ever switches it on in the car in case she breaks down so gave her the 8 and bought a new SE.
I can understand the battery on the 8 would have degraded being boxed and not used for so long but would have expected the battery health to have dropped faster causing the battery service message to come up. 92% health and battery service required?
I didn't bother trying to get to the bottom of it my mother needed a replacement for her aging Samsung and only ever switches it on in the car in case she breaks down so gave her the 8 and bought a new SE.
I can understand the battery on the 8 would have degraded being boxed and not used for so long but would have expected the battery health to have dropped faster causing the battery service message to come up. 92% health and battery service required?
Good luck to you. I had 100% battery health on my 12 PM for a little over 5 months. Now 7 months in it’s at 93%.
Another instance for why people shouldn’t put a lot of weight on the Battery Health percentage. I don’t recall which lawsuit started the whole mess, but it was a dumb response by Apple to give in and implement the ‘feature’. Battery Health is nothing more than a simple calculation of two estimated values, a design capacity for a battery size from one of the few battery suppliers (or perhaps an average of them) and the most recently measured (or projected? — as it varies at different charge levels) maximum battery charge capacity. Basically, far from spot on.
I know, this is also evidence Apple support staff shouldn’t be relying on the health value either. To that argument, I say:
• Beyond testing voltages, etc to determine a completely failed battery, Apple’s staff doesn’t have a lot of other means to troubleshoot subpar battery performance.
— Do you expect Apple to keep your device for a week, testing how long it operates during a “typical” usage before needing a recharge? (That’s rhetorical, of course, you don’t.)
• Even if an estimate, Apple needs some guideline to follow.
— Without an approximate cutoff, Apple would be required (or close enough) to replace all of the device batteries for those customers making unacceptable performance complaints based on few to no actual measurements, just poor recollection guestimates.
• Devices weren’t unusable before they included or when they don’t include battery meters. We use(d) them until the device didn’t/don't function, then recharge(d) the battery or batteries. When a recharge didn’t/doesn't replenish the power capacity, we replace(d) the battery or batteries.
Not a bad gift anyway. 
If you feel like absorbing more info...
Even the “service” message isn’t quite as one might expect.
www.wired.com
Overall, these alerts and reports can be somewhat helpful, but remember they are not do-it-all or absolute tools.
If you feel like absorbing more info...
Even the “service” message isn’t quite as one might expect.
Apple's Battery 'Service' Alerts Are a Blow Against Right to Repair
A report from iFixit finds that a "Service" alert pops up if you try to swap your own iPhone battery, even if that battery works perfectly fine.
Overall, these alerts and reports can be somewhat helpful, but remember they are not do-it-all or absolute tools.
Thanks for that interesting reading and as you say Mum is happy so that's all good.Not a bad gift anyway.
If you feel like absorbing more info...
Even the “service” message isn’t quite as one might expect.
Apple's Battery 'Service' Alerts Are a Blow Against Right to Repair
A report from iFixit finds that a "Service" alert pops up if you try to swap your own iPhone battery, even if that battery works perfectly fine.
Overall, these alerts and reports can be somewhat helpful, but remember they are not do-it-all or absolute tools.
You are putting together two different things. “Battery Health” is a percentage of a capacity that your battery can store in it in comparison to the designed numbers. It is calculated using the ohms and voltages.
“Battery service” is the message, which keeps records of cases when your battery wasn’t able to output needed max power (camera or games). Then you will see this message to appear.
Basically health is a capacity, while “service “ is a power. You can see in the market of alkaline batteries: they have 2 types. 1) long lasting but less power 2) high immediate power but less capacity.
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I have read this over and over and trying to wrap my head around it I am not an engineer. So if my battery tripped the 'service' indicator I used max power at some point? I don't play games or use the camera I am a very basic user. Email, WhatsApp and some web surfing. I guess I did something to stress the battery enough to trip the service indicator.
down to 89 percent now on my 12PM.
Another thing I’ll mention — I feel like my actual battery life is much worse. For example, If I originally got 10 hours real world use and dropped to 8.9 hours real world use I would be fine. But I feel like my actually real world run time has declined far more than the 11 percent battery health percent lost would lead me to expect
Another thing I’ll mention — I feel like my actual battery life is much worse. For example, If I originally got 10 hours real world use and dropped to 8.9 hours real world use I would be fine. But I feel like my actually real world run time has declined far more than the 11 percent battery health percent lost would lead me to expect
No worries. It is not your fault by any means. I also received this message for the first time while scrolling on my home page with apps without even playing or other thing.
Basically, battery has only 2 functions:
1) To Store the energy. We need to store it, so we could use it later without our electric wall socket. Ability to store energy is called capacity and measured by our IOS in an iphone by showing you the percentage (battery health). 100% means that you have the max capacity designed by the manufacturer and anything below 100% means it started to degrade.
2) To Output previously stored energy. Normal output power means that at any given time, the battery is possible to give the requested amount for all of the consumers: display, gps and radio module, CPU, memory and etc. Failure to provide energy for all requested parts sometimes makes your iphone restart.
Why it happened?
Only a few reasons:
1) You didn't win the battery gamble game. Yeah, every battery is unique even if they were produced at the same time. Some people have great batteries, while others don't. The only thing for which Apple is liable for is the rule of "1 year warranty/battery should not degrade less than 80% of health/for 500-1000 charging cycles, whichever comes first". Basically, even if you didn't win the gamble, the battery is still within the range to be considered as normal.
2) Battery overheated at some point. All of my iphones which eventually have shown me a "service" message were serving me as a GPS navigator map under the car's windshield in the summer.
3) Your case: sometimes battery will lose output power, if it was sitting too long in the storage and had 0% battery charge for a while. Battery cells are like muscles - if you don't train them at all, then they will degrade fast enough(recall astronauts on 1 year mission). Most likely it is your case, since the iphone 8 was introduced in September of 2017. Basically in 2021, its' battery has an age of 3-4 years, which is well enough the end of the battery life in terms of output and capacity.
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So the relationship between battery health(capacity) and output power(service message) is not truly direct. You can make an analogy by thinking of a human being. While it is mostly true that the young man at the age of 20-30 years has the maximum power in his entire life. So your expectations to see the "service message" below the 80% of battery health is pretty reasonable, because people also lose the power in the age above 30(those UFC and boxing fighters mostly lose versus young guys - Tony Ferguson is the last example, McGregor is also). But as can be seen in the real life, different situations can happen: we see the man in the age of 60, who can handle the big weights in the gym. These people say that they were never as strong in their 20-30 years as they are now at 60.
Also vice-versa is true: you can observe 20-30 years old people who can not handle even 10 lbs.
Which is quite true observation. For reference, our 12 PM at 95% shows 10hr 20 minutes of screen on.
Your 89% is not immediate reading in case if you got it from the phone itself. Most likely coconut battery will show even less, which would be more accurate number. Most likely you have 85%, which is the point when battery health starts to be noticeable. The case is that settings-battery tab in the phone itself represent only median/mean value for the last n observation months. Only Apple knows the formula. Let's say that you bought new iphone, it had 100% in the month 1, 2, 3. On month 4 you had 99% of actual health. But the system in the phone will show you 100% of health, since that was the majority of readings.
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Tthings to know.
Battery health calculation is measured using various methods over its voltage storage range and averaged with itself. Averages and educated guesses are use to help mitigate external factors. For example if you battery is very cold its more difficult to extract energy from it, this would appear to the phone as a failing battery (high amps loads causing large dips in the voltage). Using data pulled from that time period won't represent actual battery health.
Like mentioned a few times, battery health degradation isn't linear. You're battery will generally rush to around 85% before its degradation drastically slows. This is because the max voltage the lithium battery stores is near its overcharged capacity which is difficult for the chemistry to maintain. Apple's "Optimized Battery Charging" feature stops battery charging around 80% until the time its closer to coming off the charger. This keeps the voltage further away from overcharged voltages to reduce stress induced on it.
Battery health indicators takes a few educated guesses and take a few liberties for the consumer to find the percentage less confusing. For example someone above mentioned their batteries are still at 100% after months. This is because their batteries max storage capacity was above Apples pre programmed mAh rating. So to be technically accurate they just can't see the degradation of their battery because its outside (above) Apples new battery mAh value. So it could have been 110% when they bought it and its 103% now meanwhile Apple is just showing them 100%. Unfortunately no battery is that resistant to degradation when you have its max storage voltage at an overcharged state. The reason their battery may have been 110% brand new and your's might have been 100% brand new is because of variances in manufacturing.
Battery health also varies depending on many external variables so it can never be accurately calculated as a "snap shot". Apple does not show these fluctuation and instead uses a larger sample size for its averaging, so the battery might be 90% this week and Apple reports 90% but next week its 93%. Apple will keep the health menu reading 90% which is artificially low. Here is Coconut Battery tracking my iPhone 11 Pro....
![Screen Shot 2021-07-18 at 3.14.55 AM.png]( "Screen Shot 2021-07-18 at 3.14.55 AM.png")
So those dates are in order and the battery health is trending down however its not as linear as Apples health percentage would lead you to believe. Just before I was at 200 cycles my batteries health was back to 97-98 percent. Today its 85% and next week it will be back up again.
Long story short, this is why many people say don't worry about it. Battery health is an educated guess and you really shouldn't concern yourself over guesses, even educated guesses. They will warranty it if there is a problem so my suggestion would be if you are going to worry about it wait until a month before the free battery replacement warranty is about to expire and then check it to see if its below 80%.
Good luck.
Battery health calculation is measured using various methods over its voltage storage range and averaged with itself. Averages and educated guesses are use to help mitigate external factors. For example if you battery is very cold its more difficult to extract energy from it, this would appear to the phone as a failing battery (high amps loads causing large dips in the voltage). Using data pulled from that time period won't represent actual battery health.
Like mentioned a few times, battery health degradation isn't linear. You're battery will generally rush to around 85% before its degradation drastically slows. This is because the max voltage the lithium battery stores is near its overcharged capacity which is difficult for the chemistry to maintain. Apple's "Optimized Battery Charging" feature stops battery charging around 80% until the time its closer to coming off the charger. This keeps the voltage further away from overcharged voltages to reduce stress induced on it.
Battery health indicators takes a few educated guesses and take a few liberties for the consumer to find the percentage less confusing. For example someone above mentioned their batteries are still at 100% after months. This is because their batteries max storage capacity was above Apples pre programmed mAh rating. So to be technically accurate they just can't see the degradation of their battery because its outside (above) Apples new battery mAh value. So it could have been 110% when they bought it and its 103% now meanwhile Apple is just showing them 100%. Unfortunately no battery is that resistant to degradation when you have its max storage voltage at an overcharged state. The reason their battery may have been 110% brand new and your's might have been 100% brand new is because of variances in manufacturing.
Battery health also varies depending on many external variables so it can never be accurately calculated as a "snap shot". Apple does not show these fluctuation and instead uses a larger sample size for its averaging, so the battery might be 90% this week and Apple reports 90% but next week its 93%. Apple will keep the health menu reading 90% which is artificially low. Here is Coconut Battery tracking my iPhone 11 Pro....
So those dates are in order and the battery health is trending down however its not as linear as Apples health percentage would lead you to believe. Just before I was at 200 cycles my batteries health was back to 97-98 percent. Today its 85% and next week it will be back up again.
Long story short, this is why many people say don't worry about it. Battery health is an educated guess and you really shouldn't concern yourself over guesses, even educated guesses. They will warranty it if there is a problem so my suggestion would be if you are going to worry about it wait until a month before the free battery replacement warranty is about to expire and then check it to see if its below 80%.
Good luck.
I’m still at 89% on my launch 12 PM. Phone gets really warm in light use.
Since I have AppleCare+, decided to get an express replacement (rear glass also cracked, which I don’t really care about). Will at least give me a fresh battery for awhile.
Since I have AppleCare+, decided to get an express replacement (rear glass also cracked, which I don’t really care about). Will at least give me a fresh battery for awhile.
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Well damn.. 6% to go before you get a replacement from warranty. The way things are going, there maybe a battery replacement program for the 12 series sometime in the near future..
Yeah, no joke. It literally has been dropping 1% every week. As of right now its still 86%, but it'll drop again this week I am sure of it. Apple telling me nothing is wrong with my device is so full of it. This makes me want to leave Apple and get something else when I can't have my battery last near what I paid for when it was new. I don't believe they will replace it after 12 months and its getting close....
The problem is the way its going, it'll be just over 80% when it hits the one year mark for most people, and I'm sure apple won't replace the battery if it's even 81% at the 1 year mark.
My launch day iPhone 12 Pro is at 90% battery health. Never had any other phone decline so quickly.
Seems like it, but if it becomes a widespread issue, its good for us. Free battery replacement
I wirelessly charge every night using belkin MagSafe 3 in 1 charger and my battery health is on 94% on my 12 pro max