Android 9 update has destroyed battery life - can't charge, phone useless - help?

So I got the Android update alert earlier today, on a ~2 year old FP2.
Installed just fine, quite quickly, but lost all my home screens and some apps. Battery was at 48% on the completed install and then rapidly began dropping, phone heated up incredibly and it fell to 3% within 5 minutes. I plugged it in, it said it was charging 1hr 21 to full - 30 mins later it was still at 3%.

Turned it off, took out the battery and replaced with my spare. Dropped 1% a second until I ran to the charger to plug it in! Is not charging.

I’ve tried different cables, reboots, turning off and on and it is now at 1% on both batteries and there’s nothing I can do to charge it now. Any great ideas? I can’t provide any details because I can’t turn it on to check the system logs, etc

This is really, really infuriating to me as I had no idea the update was this huge or dangerous, I just trusted the installer and went ahead with it.

The phone should charge the battery when turned off.
This doesn’t work anymore, too?

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No, it won’t charge, full stop. It’s dead.

How long did you let it charging? You should try to let it charge for at least half an hour switched off.
Also, did the phone discharge also when plugged in?

First battery charged for 45 minutes, dropped from 3% to 1% in that time. Second battery has been plugged in over an hour, no effect. Seems to be holding at about 10% rather than falling but I daren’t unplug it to check as it would wipe out what little life remains.
(eta; sorry, 10% is on my third battery, the other two are at <1% and won’t turn on).

The first few days after every Android update, the phone will consume significantly more power. It does all sorts of optimisations based on usage statistics (and JIT), and these optimisations don’t carry over to the new version. Normally battery life restores after a few days. However, if your battery was already at the brink of dying, the increased load on the battery during and just after updating may have tipped it over the edge. It’s not dissimilar to how most car batteries die over winter, with harsh conditions that are suboptimal for preservation, cold and longer starts etc. Batteries just die… and always at the wrong moment. That being said, burning through three batteries in 2 years is pretty harsh.
Already given support a call? With this issue, I ether wouldn’t bother with the on-line ticket system, or file a ticket and call straight afterwards to discuss it.


I must chime in here and now to report that this issue is not caused by the Android 9 update. I have seen similar behavior on Lineage OS, too, where the phone loses power under heavy load while the battery is charged, even when just a few not very power consuming apps run in the background. There are situations in which the phone needs more energy to run than it can pass to charge the battery.

It is a hardware failure.

In this case, I would try to switch off the phone, let it cool down, and charge the battery in the night with a charger that supplies ~2 A. Do not try to charge at a notebook, its USB port does not supply enough power BY FAR!


Thanks for these explanations, they make sense to me - I’m going to let it charge, turned off, overnight on my most reliable cable and fingers crossed it’s a temporary issue that will resolve after the new update is bedded in.


Update for anyone else experiencing the same problem: left it turned off, overnight, on the best cable. In the morning the visual battery indicator suggested it was only at ~10%, but the green light was on. Turned it on and it was at 99% (this seems to be a known bug).

Still some issues

  1. Won’t charge at all when turned on, only when off

  2. Battery drain very high - 99% to 51% in 90 mins of light use (but I’m choosing to be optimistic that this is a temporary bug and will go away when the optimisation systems relearn how to manage the battery)

  3. Google photos has ‘forgotten’ it has already backed up from this device, and is now trying to reback up all 14000+ photos I have on an SD card. This may be part of what caused the original massive battery drain! I still haven’t found a fix for this.


These two issues are pretty common when the phone takes all the power it can get. At least one process seems to suck at the battery quite heavily, maybe it is point 3.

Drama like made in Hollywood: Trying to escape in a car with bad tyres and praying that they last until you are safe, because you cannot change tyres while on the run…


I also suppose there’s something wrong and some process is using full CPU power. A #dic:factorydatareset will probably solve the problem but you should first backup all your data and have to configure everything from scratch after it.
If you have a little bit of technical experience you can enable adb debugging in developer options and then use adb shell top in an adb connection to a PC to search for the CPU killing process.
You might also start your device in #dic:safemode to see if it’s an app creating the problems.

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Unfortunately I have no technical experience at all and have no idea how to do anything other than surface naive user stuff with the phone.

Does anyone know how long is reasonable to wait for the phone to reoptimise after an update? It’s been 4 days and the battery life is still useless. I don’t think this is a background app as even with no activity/use at all and the battery saver on, and the wifi turned off, the battery still only lasts 4-6 hours. 1 hour of social media apps like twitter and instagram drains nearly 50% of the charge, so this is not sustainable.

Did you try that? If not I would. Else


Even in safemode and not in use it is draining at abot 15% an hour.
I’m currently trying to back it up to do a factory reset but it’s taking time as I was hit with the google back-up bug thanks to Android 9 & it drains the battery so fast I can only back up a bit at a time…


Be aware that just restoring everything from a Google backup might also restore the configuration creating the battery drain. So in addition to the Google backup you might also copy all internal data, pictures, audio media, messenger data etc. to e.g. a PC to be able to configure your device “from scratch” again in case this might proof to be necessary.


A full reset hasn’t solved the problem. Still losing 15 - 30% battery life PER HOUR.

I’ve raised a ticket with support, but this is so frustrating. I need the phone for work and I may be forced to buy a new, non-fairphone replacement. Ugh.

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As you already did the factory reset you could consider to manually downgrade back to Android 7 and then try to upgrade to Android 9 again, probably before any apps are installed.

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Maybe it’s related to your sim card. Can you try to leave it out for one hour just to compare?

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Yes I’ve taken my sim card out (and my SD storage card). No dice.

I’m going to wait for support to get back to me before I waste my time trying anything else. I hope I can get a spare phone to use instead for next week :confused:


And I assume the drain happened before you installed anything from the backup, right?
You might also try to give support a call during the week in case your ticket might not get an answer fast enough, as it seems urgent.

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