Is My Battery Dead?


I bought a Fairphone 4 from a French Reselling Website ( a year and a half ago. I believe the phone is 2 years/2 and a half years old. I recently noticed battery problems : the battery does not last a full day (and I do not use my phone all the day), when charging overnight, the phone may sometimes not fully charge, altough it is powered off. Also, when I plugged in this evening, and turned of bluetooth+hotspot, the battery still decrased to 3 percents (it was around 20 initially). I saw with BatteryBot Pro that the voltage when charging was around 3.6-3.8 V (with different chargers, but never the official one), which I believe to be a bit low.
I was wondering if the problem was from my chargers, my battery (which I believe to be the case), or from other factors.
Oh, and I have 5G activated all the time.

Thanks for any help.

PS : Sorry for eventual grammar mistakes, english is not my first language (french is).

Vous pouvez d’abord essayer un kickstart pour réinitialiser le logiciel de la batterie.
Si vous avez de la chance, il y a un Fairphone Angel dans votre quartier et l’Angel a un module inférieur pour un Fairphone 3 pour tester votre téléphone.
Traduit avec l’aide de

First you could try a kickstart to reset the software of the battery.
If you are lucky there is a Fairphone Angel in your neighbourhood and the Angel has a bottom module for a Fairphone 3 to test your phone.

Thanks for you answer. But you seems to have proposed solutions for fairphone 1 to 3, and I use the fairphone 4. Will it still work ?

Yes, it is a good method to reset the software.

Honestly it makes a lot of sense to just assume the battery is old and buy a new one. I did that to my two-year-old phone when it started to drop from 48% to no-power-at-all instantly when the temperature fell, and suddenly the battery lasted three times longer :slight_smile: don’t buy one unless you plan to use it, though – the major thing that degrades li-ion batteries over time is oxidation, so they start ageing even if you don’t use them for anything at all.

But being able to do this is one of the benefits of having a Fairphone: exploit it!