In my quest to 'consolize' a switch into a Switchn't I wanted to remove the requirement for a battery.

Not much has been done to figure this out but I did find a thread on shmups in which user fwannmacher had over time figured it out after their battery failed.

First step, there are two test points next to the battery connector (on V1 and V2 switches, yet to confirm lite or oled) that are for the Sense line and GND. Putting a 10k ohm resistor across those pads makes the switch think the battery is fully charged, and will no longer try to charge it.


Next step, the switch requires voltage into the batt circuit or it will not turn on. A DC to DC buck converter from the 15V rail on the switch dock motherboard is a perfect solution for this.
Before connecting the buck converter to the battery input on the switch motherboard, I set its output voltage to 4.22v on my digital multimeter and then connected the output wires to the switches battery input.


Now with buck voltage output at 4.22v on meter I then dialed it in to 4320mv in Hekate (4.30v on meter), hekate has battery info under Console Info/Battery.
This screen unfortunately doesn't auto refresh, so I was making very minute adjustments on the buck converters adjustment screw, then closing and reopening the battery screen to check the new value.
(I got the value of 4320mv from a second fully charged switch I had on hand, but I recommend you check what your console is before beginning modification)



With all this complete the switch now boots completely without a battery, both into OFW and CFW.


Thanks to fwannmacher for their work. I just wanted to do a complete writeup thats a little easier to follow for people in the future and hopefully extending the lifespan of some switches.

 

[BlackZero500]

I really like this project. I really hate the fact that even on the Docking Station you will not work with the power from the station but just constantly charge the battery you are using. that is very bad for the battery. Also this way you could fix a console with a defective battery or charging circuit.

What i think would make this project really perfect would be a version in which you do not remove the battery but kinda decouple it while you are using a charger. Either relatively simple via a Switch or if thats possible via circuit to detect if a charger is present. if it is you cut the battery from the mainboard but still charge it until its full.

But that is only an idea. This project is pretty awesome as it is.

 

[WalangAlam]

is there a project that can charge a battery with damaged mt92 using a small charging board?

 

[TheStonedModder]

I really like this project. I really hate the fact that even on the Docking Station you will not work with the power from the station but just constantly charge the battery you are using. that is very bad for the battery. Also this way you could fix a console with a defective battery or charging circuit.

What i think would make this project really perfect would be a version in which you do not remove the battery but kinda decouple it while you are using a charger. Either relatively simple via a Switch or if thats possible via circuit to detect if a charger is present. if it is you cut the battery from the mainboard but still charge it until its full.

But that is only an idea. This project is pretty awesome as it is.

I don’t think it’s that bad for the battery tbh. The os must be handling the discharge process somehow

I’ve had a launch day switch docked and running 24/7 for over a year for a Twitch plays stream and it’s battery still works just as well as the day I bought it

 

[Jayro]

It might be worth taking the BMS PCB off the battery itself, and basically just keep the cell off the circuit. See if that keeps the Switch happy.

 

[BaamAlex]

First off all, nice work. A case for this would be awesome. But who knows what the future offers.

 

[FueledSamantha]

I really like this project. I really hate the fact that even on the Docking Station you will not work with the power from the station but just constantly charge the battery you are using. that is very bad for the battery. Also this way you could fix a console with a defective battery or charging circuit.

What i think would make this project really perfect would be a version in which you do not remove the battery but kinda decouple it while you are using a charger. Either relatively simple via a Switch or if thats possible via circuit to detect if a charger is present. if it is you cut the battery from the mainboard but still charge it until its full.

But that is only an idea. This project is pretty awesome as it is.

For the switch to not crash during power source switching from power outage, you would have to have it powered from the battery just like a UPS system... so a factory configuration haha.

is there a project that can charge a battery with damaged mt92 using a small charging board?

Not that I am aware of, im sure you could jerry rig it to a smart lithium charger somehow?

I don’t think it’s that bad for the battery tbh. The os must be handling the discharge process somehow

I’ve had a launch day switch docked and running 24/7 for over a year for a Twitch plays stream and it’s battery still works just as well as the day I bought it

Yes the firmware is managing a charge discharge to a certain extent, more specifically managing the battery heat. As the system actually uses 4.2v to some components (which is why it wont boot at all without a battery connected) so its impossible for it to not use the battery somewhat.

It might be worth taking the BMS PCB off the battery itself, and basically just keep the cell off the circuit. See if that keeps the Switch happy.

Interesting thought, but as stated above, it would still need a 4.2v source, so this solution seams simpler as its more compact.

First off all, nice work. A case for this would be awesome. But who knows what the future offers.

The 3D printer hasn't stopped spitting out variations perfecting fitment.

 

[WalangAlam]

Not that I am aware of, im sure you could jerry rig it to a smart lithium charger somehow?

this is my plan. will there be back flow of current from smart lithium charger to the rest of the board or to the m92?

 

[Foxi4]

It might be worth taking the BMS PCB off the battery itself, and basically just keep the cell off the circuit. See if that keeps the Switch happy.

That’s the way I would’ve approached it but then again, there’s a more important thing to test. You could technically splice directly into the respective voltage lines and bypass the battery/charge circuitry altogether, which seems more reasonable than feeding the Switch with a “fake” battery input and tricking it with a “fake” load on the sense pins. Not that it matters much - the efficiency gain would probably be minimal, so whatever works, works.

 

[FueledSamantha]

That’s the way I would’ve approached it but then again, there’s a more important thing to test. You could technically splice directly into the respective voltage lines and bypass the battery/charge circuitry altogether, which seems more reasonable than feeding the Switch with a “fake” battery input and tricking it with a “fake” load on the sense pins. Not that it matters much - the efficiency gain would probably be minimal, so whatever works, works.

I might still look into this, the main charge controller is the BQ24193 but it does communicate serial data with the soc so much more difficult to bypass as it may not boot at all without it.


Progress being made, final version of the main shell for this cooling setup. Just needs a lid haha.

 

[BaamAlex]

I love it. But in case you need Hekate, you can't boot it then because Hekate doesn't work on tv. Is there a solution planned for the future?

 

[TheStonedModder]

I love it. But in case you need Hekate, you can't boot it then because Hekate doesn't work on tv. Is there a solution planned for the future?

If you set up auto boot properly that’s nbd since the system will reboot straight to atmosphere

 

[JonJaded]

I might still look into this, the main charge controller is the BQ24193 but it does communicate serial data with the soc so much more difficult to bypass as it may not boot at all without it.


Progress being made, final version of the main shell for this cooling setup. Just needs a lid haha.
View attachment 369078

Looks great! For a sec, I thought that was CNC alluminum, and that just reminded me that if the case was fully alluminum and made as a heatsink, it would probably passively cool itself with its low wattage.

 

[BaamAlex]

If you set up auto boot properly that’s nbd since the system will reboot straight to atmosphere

That's not what really mean. Dunno how i should describe that. What is when you do this mod at first and then creating an emummc?

 

[FueledSamantha]

I love it. But in case you need Hekate, you can't boot it then because Hekate doesn't work on tv. Is there a solution planned for the future?

I have a spare LCD sitting around that I external mount to test and configure with, but as long as I keep hekate_ipl.ini configured correctly, there shouldn't be a need to use it after initial setup.

Looks great! For a sec, I thought that was CNC alluminum, and that just reminded me that if the case was fully alluminum and made as a heatsink, it would probably passively cool itself with its low wattage.

Haha, its just 3d printed in transparent PLA, my cnc router would need a massive upgrade to do allu.
Yeah I had a few other design idead for cooling but nothing came up in time for ToTK release, I wanted to use a cooler off a low profile graphics card etc but ended up just stacking two stock heatsinks.

 

[Foxi4]

I might still look into this, the main charge controller is the BQ24193 but it does communicate serial data with the soc so much more difficult to bypass as it may not boot at all without it.


Progress being made, final version of the main shell for this cooling setup. Just needs a lid haha.
View attachment 369078

Oh, I’m not suggesting that you should take a hacksaw to it, but you raise a good point - you’d still have to fake the presence of a battery somehow, you’d just cut down efficiency loss on bucking the input and boosting the output.

 

[fwannmacher]

I'm glad to see that my little project helped someone

Post automatically merged: May 8, 2023

In the case you want to replace the fan here is the pinout.

 

[mohawktim]

Can I wire in a USB charger wire into the wires so I can charge and play with battery backup my USB c port is fukt

 

[Nakamichi]

Im really, really excited by this project.
Finally having a use for heavily damaged Switch units is fantastic!

Im gonna be looking for a good deal on one of those specifically to follow in your footsteps!

Having a tiny little Switch console, constantly running at high clocks, perhaps even with improved cooling or a LAN-port by using an Oled Dock as a base and an internally hooked-up USB-HDD... i cant stop dreaming about the possibilities here!

You rock <3

 

[fwannmacher]

I have gone for a bulkier route as I wanted to keep the screen for accessing Hekate and I wanted to be able to use the system for charging the Joy-Cons. Other than that I overclocked the hell of it so I have used a 140mm Noctua Fan (: