Here's a quick and easy fix for the turning off at 40% battery issue that people are seeing after running Linux. This is effectively the same fix as unplugging the battery, but does so without having to take apart the Switch.

Step 1: Download attached fusee-linux-battery-fix.rar
Step 2: Extract and load the binary with your favorite RCM Smash tool (I'm using TegraRcmSmash).
Step 3: You should see the typical fusee screen, at this point unplug the USB cable. The screen should go off.
Step 4 (optional?): Hold the power button for 10 seconds. Your switch won't turn on at this point, that's desired.
Step 5: Plug in a USB cable. Switch will turn on, and you're done.

This worked to fix my Switch, let me know if it works for you.

Edit:

Source is here:

github/crystalseedgba/BatteryFix/blob/master/fusee/src/main.c (Sorry it's not letting me post hyperlinks)

This doesn't fix the Linux bug, this is really just a crude workaround. At first I suspected that Linux is somehow mangling the battery gauge but this doesn't seem to be the case. The battery gauge reports around 40% and decent battery voltage when my Switch would turn off. I think Linux is misconfiguring some undervoltage lockout somewhere, but I don't know where.

Thanks to jjbredesen for his "How to make a custom Fusee payloads" tutorial.

 

[xXxSwagnemitexXx]

I will be really surprised if this is a real fix

same

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im letting my switch charge to 100% before running this because... i dont really know why im waiting for it to get to 100% but when it does ill run the payload

 

[LeRepex]

same

I tought it was fake at first but as it seems it really fixed my problem as the lowest i go for was 7% while running mario odyssey after that i started charging again but maybe it would go even lower

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same

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im letting my switch charge to 100% before running this because... i dont really know why im waiting for it to get to 100% but when it does ill run the payload

I didnt do this either. i ran it with almost 50% and it worked

 

[xXxSwagnemitexXx]

I tought it was fake at first but as it seems it really fixed my problem as the lowest i go for was 7% while running mario odyssey after that i started charging again but maybe it would go even lower

thanks for the info, at least someone got it to work, im gonna try running it now.

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ill take pictures as well (with my laptops front facing camera because i dont have my phone)

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camera wont work but i injected the payload and i got the rocket ship and moon thing and the words (re)switched and underneath it says " BATFET is now disabled, disconnect the USB cable."

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unplugging turned the switch's screen off

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Step 4 (optional?): Hold the power button for 10 seconds. Your switch won't turn on at this point, that's desired.
Step 5: Plug in a USB cable. Switch will turn on, and you're done.

did this and my switch turned on, im going to decrease the battery now

 

[Notex]

I just ran it and going to let my switch battery's drain, if it goes below 40% I'll update this post.

Edit: Battery at 35% and Switch hasn't powered off yet. Looks like this has fixed the battery bug.

 

[xXxSwagnemitexXx]

MY NEWS ARTICLES GOT RESET

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not exactly reset, but "Welcome to News!" and "Where to get new games?" are at the top of the news page

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[Notex]

MY NEWS ARTICLES GOT RESET

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not exactly reset, but "Welcome to News!" and "Where to get new games?" are at the top of the news page

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Am I the only one who doesn't use the news channel at all? I get gaming news from Reddit and sometimes from gbatemp instead.

 

[LeRepex]

Am I the only one who doesn't use the news channel at all? I get gaming news from Reddit and sometimes from gbatemp instead.

No I don't use it either

 

[xXxSwagnemitexXx]

i read some of it sometimes

 

[xXxSwagnemitexXx]

currently at 68%, everything is fine

 

[x0x0]

I doing this same, gonna discharge battery i hope it works.

 

[angelhp]

20% im playing super mario odyssey
this payload look like fix the battery
Edit: Low battery......well

 

[Zumoly]

20% im playing super mario odyssey
this payload look like fix the battery
Edit: Low battery......well

Are you getting the low battery warning?

 

[angelhp]

Are you getting the low battery warning?

Yes

 

[Zumoly]

Yes

Then this fix is legit!
Looks like OP found a software way to temporarily disconnect the battery. Lakka.tv here I come!

 

[angelhp]

Definitely I can affirm.
This payload works flawlessly.
the console has shut down correctly 0%
the console has entered in standby mode and not in off in abrupt
Thanks =)
I have loaded the battery a bit after shutting down correctly and the game continues
Amazing!!!!

 

[SomeGamer]

Big thanks OP, gonna actually charge my Switch after months then run this!

 

[xXxSwagnemitexXx]

i can also confirm that this works

 

[Sgt. Lulz]

I'm interested in the source code as well, and I'm sure it'd prove incredibly useful if integrated into a payload like CTcaer's Hekate.

 

[xXxSwagnemitexXx]

I'm interested in the source code as well, and I'm sure it'd prove incredibly useful if integrated into a payload like CTcaer's Hekate.

agreed

 

[SomeGamer]

I'm interested in the source code as well, and I'm sure it'd prove incredibly useful if integrated into a payload like CTcaer's Hekate.

Yeah, like before every shutdown.