Battery draining investigations


It seems that there are now quite many who has received Chestnut phone and reading some reviews around the internet it seems that current battery duration is around 2-3? hours.

I personally can test and start trying to figure out what is currently draining battery and help Purism to improve battery life as fast as possible.
Possible there are others in the community who can help as well.

If anyone already have expertise on this area?
We can start gathering information what tools can be used and what to trace, log, etc…

Troubleshooting and Knowledge

Current issues:

Terminal commands for analysis:
$ upower -d


In this video by @hackersgame he is using some kind of tool to measure the power used for a Librem 5 Birch phone:

I don’t know exactly what tool that is or how it works, but it seems useful since it seems to allow you to separate issues with the battery itself from issues with the power consumption.


Related issues are listed here:


Love the idea, but alas people don’t seem to be too interested in the electrical engineering side of the phone. I tried to find people who were interested in the schematics when they were published, but almost nobody wanted to talk about them in the forums.
I’d have loved to tinker around with the librem 5 hardware and could barely wait, but in the end I canceled my order (and dont regret it), so I will never be able to play around.

But if anyone wants to investigate on his or her device I’d love to help. You’d need at least one good quality multimeter (better two or more) and likely some decent soldering equipment along with the confidence to solder small, bipolar SMD-parts.
We’d best try and work out a nice script that puts the phone through some sort of standard usage (thank god it’s Linux! :)), while we meassure the power-consumption on all the power-rails one after the other. That can give us a hint which parts waste the most energy and wether its a hardware issue. It might be also a good idea to analyse the various dc-dc-converters and figure out if any of them is oscillating at any load-scenario. That’s where an oscilloscope is necessary.

In order to investigate the circuitry’s behaviour under various supply voltages I’d run the phone without a battery but supplied from a stable lab-supply at interesting, stable voltages.

On the schematic side it might pay to search for the drop-out-voltages of the various converters. Perhaps one of them has a too small drop-out-voltage, which would explain a lot. I had a quick glance at this when the schematics came out and I didn’t find any on the spot, though. I also checked some of the part’s quiescent currents in the vain hope to find any significant leakage.

If anyone is up for investigating I’d really love to help, but really I doubt that there is anybody out there, as I assume that very few people who have the requisite equipment have backed this project to the very end, due to purisms dismal performance on publishing usable, professional information on the electrical engineering side that instilled even a bit of hope.
Yet, if there really are people who lack the equipment but have a strong interest and a phone and are close to western bavaria we might be able to spend a couple of evenings investigating with my equipment.


I don-know, but I thought it was the way everyone did it to hugely slow the clock down during sleep.

And design key software like the display manager to sleep as much as possible, between finger swipes for example.

I imagine that some of the most basic things with the software and hardware interface will need to be carefully examined. You just can’t run the CPU very much and still have any battey life.

The thing needs to be quiet most of the time (I mean waiting and not looping).

No doubt this will be a struggle that will take years to fix. But I’m sure it can be fixed, and well.


Little OT:
Would be funny though if running Android on the librem 5 would result in less battery drain - not because anyone would want this but because it would be irony of fate after all the people telling “hey don’t bother battery drain / performance as it’s linux and not android”

EDIT: to make it less off topic:
in the unlikely case of having android running on a l5 without performance or battery issues it would however show that the librem 5 can be fixed with software.

Regarding being quiet most of the time. Would it be possible to run most of the time only one core?


Yes you can run just one core! I’m running tests atm. I’ll put out a video soon. :slight_smile: