Fast battery draining only while turned off. Is there a way to fix this?

[Adora]

Hello,

A few month ago a purchased three refurbished iPhones: 8 Plus, SE2 and SE3.

For a while I used the 8 Plus and SE3 daily.

Now I am using the SE2 and turned both other phones off, with an almost or completely full battery. But every time I turn on one of them on after just a few days the battery is completely empty. I did not notice any fast discharging while using them daily, also the battery section in settings shows they are in a really good shape, so can't be the original ones, at least for the 8 Plus.

This "Find My Network" thing what can send the location while turned off is deactivated for both.

What could cause this? Maybe there are 3rd-party batteries in the phones and not originals from Apple. But wouldn't I notice this too while using it or see something in the settings?

Is there a way to re-calibrate the battery or anything like that? And can I find out, what kind of battery is in there without opening them? I just noticed I still have this coconutBattery app installed on my Mac.

This discharging when turned off doesn't even happen on my SE1 and 4s, if I turn them on after several months. They still have the original battery. Only a 5s what I also have lying around here has this problem too, but it isn't really usable when not permanently connected to power. A full battery might last 1-3 Minutes. So that's simply an almost dead battery.

 

[BugeyeSTI]

If they weren't refurbished by Apple they definitely have 3rd party batteries in them or possibly the original battery that came with the device. I'd say in either case, the batteries are causing the issues you're describing. If they do have 3rd party batteries there probably defective or just poor quality and if it's an original battery it's probably worn out. Are you getting a battery health reading in the battery section?

 

[now i see it]

I’ve got an iPhone 7 that I use only for an air quality monitor display. It’s on 24/7 and plugged in and it’s battery is thrashed - and I don’t care.
When I turned off that phone for a day, battery at 100%, the battery was completely discharged the next day when I turned it back on.

So yeah - a thrashed battery won’t hold a charge

 

[Adora]

If they weren't refurbished by Apple they definitely have 3rd party batteries in them or possibly the original battery that came with the device. I'd say in either case, the batteries are causing the issues you're describing. If they do have 3rd party batteries there probably defective or just poor quality and if it's an original battery it's probably worn out. Are you getting a battery health reading in the battery section?

Both were turned off about 14 hours ago with 100% charge. The 8 Plus didn't lose anything the SE3 dropped down to 92%. A few days later both will be completely empty I tested it several times now.

The Maximum Capacity looks very good for both devices. Can 3rd-party batteries fake the Battery Health that is displayed?

45 minutes later the SE3 is already down to 90% and I did nothing with it, the 8 Plus still at 100% and I used it the whole time, because the screenshot didn't sync until I changed the VPN location.

Edit: The drop from 92 to 90 happened while using it to do the screenshot and sync it. After that it stayed at 90%.

I will now connect them to my Mac to see what coconutBattery is showing.

8 Plus:



SE3:

 

[Adora]

I connected both to the same port on my Mac and one is showing 3W and the other on 13W, strange.

They have both a 12 month warranty. Maybe I'll send them just back. I Have good experience with this website, just got my money back two times and one of them was even a few days over the 30 days return window. Strangly I only had problems with iPhones there, the iPads are all good.

It's a website called refurbed.de here, but also available in several other EU countries, it will ask to redirect if you visit it from a different country. It looks like a shop, but almost every item I bought there was from a different reseller.

 

[Adora]

I just tested also the SE2. It has the same manufacturer for the battery and it's much older, but has not those discharging problems when turned off. Also looks like the Battery hasn't been charged before bought it, because of the low cycle count.

 

[Adora]

This fast battery draining while turned off seems not to exist anymore since the last iOS updates. That's really weird because one is on iOS 18 Beta and the other one on iOS 16 and no update before has fixed this.

Could also be three days off is too short, but they didn't lose a single percent and last time it had been less than a week where they both were completely empty.

Maybe something recalibrated the batteries because I charged both from 0 to 100 last time and the combination doing an update while charging helped somehow.