Battery Disconnect Usage

So I know that in the BIOS you can enable a battery disconnect option which is meant as a convenient alternative to unplugging the battery when working on the device. I was wondering if this could be used in situations where you expect the laptop to be plugged in at a desk for long periods of time to avoid putting stress on the battery. If so is there a way to enable it beyond just doing it in BIOS when turning the computer on?

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It will save if you enable battery disconnect, do not have a unit to confirm it. Using it at a desk is the intended purpose. My brothers laptop had the battery inflate and crack the battery casing from charging while using it.

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Sadly Josh is wrong. I agree it would be a useful feature (along with battery charge level control) but the battery disconnect is only available for the immediate boot after setting it in BIOS. It does not remember. In fact, I think it might be disabled the moment that it receives new charging input signal.

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Ah, yep I do know some PC BIOS settings does not save, would’ve wished it would work like that.

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From what I read somewhere else, it seems like the disconnect setting resets itself every time when AC power is plugged in. So that’s a bit of a bummer but I can see what it is the case. I agree with everyone’s comment though, this should be a setting that can be saved/memorized by the bios.

EDIT: Here is what I just tried. I have my laptop (running 3.03 BIOS) connected to the power. The machine is powered down (running Windows 11) completely (not that hyper-sleep crap). I rebooted the machine and went straight to the BIOS, enabled Battery Disconnect, save and exit. The laptop shuts down again (I think it is expected behavior but strange it didn’t just reboot itself). I powered the laptop back on, logged into windows and strangely now the laptop is solely running on battery power?? What am I missing here. Did I do anything wrong in the steps to enable the Battery Disconnect option? It doesn’t seem like it is working the way it was intended to at all.

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@Matrix1999 If you unplug the laptop, trigger Battery Disconnect, then wait 20-30 seconds, are you able to turn the laptop on?

If it’s working as intended, it should not turn on.

Right but that’s not my point of using it. All I want Battery Disconnect is so that when I am in the office, I want the laptop to use the power straight from the USB-C and have the battery disconnected. That is how I understand what people would use it for. If this has another use case for it, then I’d like to know what it would be.

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Is there any update on this?
If its not possible right now will that change?

@Matrix1999 Well, I believe the other use case is for system maintenance - when you open up the machine, you can further decrease the chance of shorting something out before you unplug the battery.
Also, I believe I understand the safety*/UX reason for this setting not persisting - if you forget you disconnected the battery and disconnect power, you’re going to have a bit of a shock and potentially a really bad time, depending on what the machine was doing at the time. But that doesn’t mean persistence of this feature shouldn’t be possible. There could be a second setting (maybe even an intrusive warning when you try to enable it) to make it persistent.
*mostly data safety - but abruptly disconnecting wall power from a powered-on machine with the battery already disconnected isn’t really the intended use case for the hardware

Anyway, I wanted to piggyback on the other take on Daviel_Banister’s question - separate from persistence of the BIOS setting, I came to this forum hoping to find utilities to toggle this setting from within Windows and/or Debian, or at least confirm that such utilities could or could not exist.
The simplest implementation of such a utility (if any implementation is possible) might only flag the battery to be disconnected the next time the BIOS launches an OS, but (and in my limited understanding, this seems less likely) it would be more useful (duh) if you could actually connect and disconnect the battery from within the OS.
Is it too much to hope for an authority like a Framework dev/designer to comment?

One can always hope. What’s life without it?

The solution I found was to set the battery’s max charge to 65% in the bios. This gives me plenty of battery life for my classes while avoiding excessive battery wear.

Workaround.

You can use this tool to stop and start charging while the system is running.

Do you mean

ectool batterycutoff

It tells you to shut down immediately. So I am not sure it could cause some damage if the notebook is used for a longer time with batter cutoff. Does anybody know?

No, I mean chargecontrol idle (I think). It just stops the controller from charging the accumulator until you set it to normal or reboot.