Battery Charge Limit

[Cesese]

Please allow us to set charge limits on the Steam Deck. It'd be nice if we could do it directly from SteamOS, but even just getting it on the BIOS would be a good start. The best would be, ontop of getting an option in the KDE Advanced Power Settings, to also make it into Steam's power settings menu (with FPS limiting etc.)
I plan on using my SteamDeck a lot plugged in, so I don't want to charge it to 100% when doing that.

• Here's what I want: https://i.imgur.com/rOuMRjn.png
  
• Here's what we have: https://i.imgur.com/iNgMNKw.jpeg (BIOS) / https://i.postimg.cc/LsFh2FF1/D4-E68918-1361-46-DF-A149-6-A7-EEFB50465.jpg (SteamOS)

[Tony]

Use Decky Loader Powertools, I swear the guys who made it are brilliant (I looked at the code) and it does the job when Deck is on. Disconnect power when Deck is off.

[emberfiend]

no, your hyperbolic situation is obviously unlikely. but more eyeballs = more comments and more awards, things that fall off the front page are unlikely to be interacted with again as few people scroll to p2/p3 or use search. and it's likely imo that they are looking at this forum sorted by thread activity as one metric for what users prioritize in feature development. feel free to unsubscribe if the bumps annoy you

[emberfiend]

I'm glad that Decky Loader exists but those of us who are keeping the software vanilla for stability/performance/security reasons would like these features too :)

[~Senpai]

Publicado originalmente por JDGBOLT:

Just to throw it out there, the newest deck Linux 6.1 kernels that are inside of the main channel which will eventually launch as 3.5 does have charge limit functionality in place. I currently have my deck setup to have a 90% charge limit, which it'll drop to 80% if it's been plugged in for a while, which seems a decent balance of increasing battery longevity while also still keeping a usable amount of battery life. You just have to do like>

echo 90 > /sys/class/hwmon/hwmon4/max_battery_charge_level

as root and it will stick around and stay that way even when the deck is off or asleep, as it directly talks to the deck's onboard microcontroller that handles the charging, so mine is always limited to 90%. They will probably put in a setting in steamos itself but just thought I would say it's possible right now to have a battery charge limit if you don't mind running the 3.5 prerelease.

Just coming back here to update this:

With the non-dev preview branch now updated to 3.5, you may run into a permissions issue when trying to change this setting in Konsole:

sudo echo 80 > /sys/class/hwmon/hwmon4/max_battery_charge_level
bash: /sys/class/hwmon/hwmon4/max_battery_charge_level: Permission denied

Apparently the ">" operator attempts to run before sudo, meaning that you technically aren't running this command as root and it fails.

To fix this, use this command instead:

echo 80 | sudo tee /sys/class/hwmon/hwmon4/max_battery_charge_level

You can verify this is set with the following command:

cat /sys/class/hwmon/hwmon4/max_battery_charge_level

Happy charge limiting!

EDIT: One more update here because this is REALLY interesting - It looks like PowerTools recognises if you're on SteamOS 3.5 and alters this setting directly! So previously where PowerTools charge limit would not work with the Deck turned off, now it DOES!

I'll keep an eye on things incase I'm wrong but that's a HUGE W for PowerTools if this is true.

[Rodomar705]

Publicado originalmente por ~Senpai:

Publicado originalmente por JDGBOLT:

Just to throw it out there, the newest deck Linux 6.1 kernels that are inside of the main channel which will eventually launch as 3.5 does have charge limit functionality in place. I currently have my deck setup to have a 90% charge limit, which it'll drop to 80% if it's been plugged in for a while, which seems a decent balance of increasing battery longevity while also still keeping a usable amount of battery life. You just have to do like>

echo 90 > /sys/class/hwmon/hwmon4/max_battery_charge_level

as root and it will stick around and stay that way even when the deck is off or asleep, as it directly talks to the deck's onboard microcontroller that handles the charging, so mine is always limited to 90%. They will probably put in a setting in steamos itself but just thought I would say it's possible right now to have a battery charge limit if you don't mind running the 3.5 prerelease.

Just coming back here to update this:

With the non-dev preview branch now updated to 3.5, you may run into a permissions issue when trying to change this setting in Konsole:

sudo echo 80 > /sys/class/hwmon/hwmon4/max_battery_charge_level
bash: /sys/class/hwmon/hwmon4/max_battery_charge_level: Permission denied

Apparently the ">" operator attempts to run before sudo, meaning that you technically aren't running this command as root and it fails.

To fix this, use this command instead:

echo 80 | sudo tee /sys/class/hwmon/hwmon4/max_battery_charge_level

You can verify this is set with the following command:

cat /sys/class/hwmon/hwmon4/max_battery_charge_level

Happy charge limiting!

EDIT: One more update here because this is REALLY interesting - It looks like PowerTools recognises if you're on SteamOS 3.5 and alters this setting directly! So previously where PowerTools charge limit would not work with the Deck turned off, now it DOES!

I'll keep an eye on things incase I'm wrong but that's a HUGE W for PowerTools if this is true.

You need BIOS 116 for this, they have added the handlers to do this from a software level, just for your info.

[Tony]

Yeah just do

sudo bash -c "echo 80 > /sys/class/hwmon/hwmon4/max_battery_charge_level"

[Jiggy007]

Is the SteamDeck able to enter PSU-mode while docked and plugged to the PSU (PSU = Power Supply Unit / Charger)?

What I want, is: Steamdeck stops using battery when it is in PSU Mode. And I can set a Threshold to not charge the battery while being in PSU Mode. Like.. Max charge 80%. And only start charging when below 75%. And when in PSU Mode, Battery wont be used, AND wont be charged either and just stays at.. lets say 78% (according to the set threshold)

[emberfiend]

You're describing a charge limit. The posts above yours are talking about how to do this with the new kernel in 3.5. It isn't in the stable branch yet though unfortunately :(

[☣cнCZ¡ρŋ¡ pitcho®☣]

Publicado originalmente por Tony:

I am not sure what bumping will achieve. It's not like devs will say, "ooh, that thread on battery optimization which we never looked at got bumped, we better do this and publish the update tomorrow".

If we don't address it, the developers will leave it as it is, if we propose a feature that would appeal to a number of users, there is at least some chance that the developers will take note. If you're not interested, just ignore it.

[Tony]

I am interested. Yeah "bump" seems a low effort post, but may be it is sufficient to keep the interest alive.

[NGniusness]

I guess I should do my due diligence and bump this too. But to not make it low effort, here's some stuff to add to the conversation too.

I'd also love to have this in vanilla SteamOS, since there's obviously demand for it based on the amount of people who have asked me (the PowerTools dev) about the setting. I'm pretty hesitant about recommending this to the average user though, since the default battery charge behaviour is quite good and prevents some issues that can come up if you never let the battery fully charge & discharge.

Publicado originalmente por ~Senpai:

EDIT: One more update here because this is REALLY interesting - It looks like PowerTools recognises if you're on SteamOS 3.5 and alters this setting directly! So previously where PowerTools charge limit would not work with the Deck turned off, now it DOES!

This was added in PowerTools v1.4.0, but it's got a sort of dumb bug: it doesn't disable the charge limit when you turn it off in the PowerTools UI. Should be fixed in next PowerTools update.

For older kernels, PowerTools will fallback to the old slightly sketchy way of setting the battery limit by directly talking to the battery management chip. For people who like the vanilla experience, this is technically possible to do without PowerTools but it's a bit complicated so I don't want encourage regular users to do it. If you're an advanced user, the implementation is the last part of this file https://git.ngni.us/NG-SD-Plugins/PowerTools/src/branch/main/backend/src/settings/steam_deck/util.rs#L104
(e.g. call set(Setting::ChargeMode, ChargeMode::Idle as u8) to do passthrough charging, set(Setting::ChargeMode, ChargeMode::Normal as u8) for regular charging).

Publicado originalmente por Jiggy007:

Is the SteamDeck able to enter PSU-mode while docked and plugged to the PSU (PSU = Power Supply Unit / Charger)?

What I want, is: Steamdeck stops using battery when it is in PSU Mode. And I can set a Threshold to not charge the battery while being in PSU Mode. Like.. Max charge 80%. And only start charging when below 75%. And when in PSU Mode, Battery wont be used, AND wont be charged either and just stays at.. lets say 78% (according to the set threshold)

By default, the Steam Deck does this at 90%, though it will charge up to 100% when it goes below 90%. Generally, you don't need to change this since that's a quite reasonable limit. It's commonly called passthrough mode, since the power from the charger is passed directly through to the Steam Deck hardware, bypassing the battery.

[emberfiend]

bump

[Jiggy007]

Im not sure what I did wrong. I installed Decky Loader and then PowerTools 1.4. I turned on the Charg eLimit Feature to test it. My Deck is currently at 84% and I set it to max 88% to see if it will stop charging.

The thing is, it is now stuck at 84%. It did not charge to 88%. Is there some kind of buffer zone, like, it has to be 5%-10% below the max value, so it will start charging?

And I read, that currently there is a bug, prevent you from turning off the charge limit. You need to do it manually via commands. I know how to do this. But just to confirm: to reset everything to default again, the value of the command-start must be "echo 100" right? not "echo 90"?

[Tony]

Yeah I would think it should start with "echo 100".

By the way, did 3.5.5 implement this natively?

[EridanFresh]

Some weird shenanigans are happening to me. I can't seem to be able to turn off the charge limit, even removed PowerTools and still my Deck is not charging while on 70% even after several restarts..