Original Post

I’ve been playing Virtual Boy for a week or two now, using the AC adapter my VB was sold with. Works great, but I’d really like to be able to play on batteries. A quick look around and an OEM AA battery casing goes for around $30USD. Well, I’m unfortunately on a budget, and I’m not ready to drop 30 bones on a piece of plastic. I may be low on funds, but I have lots of scrap materials and a box full of 18650 Lithium-Ion batteries that I salvaged from discarded laptop batteries. I figure that if the VB usually runs on 9v, then it might be able to run on 2 fully-charged 18650’s for ~8.4v. Worth a try!

I used the methodology of first making it FUNCTIONAL, and then later making it PRETTY. So this is a very ugly build.


I hacked off part of the casing of one of the laptop batteries. I have plenty of spare springs from other discarded electronics.


Some scrap plastic and chunks of metal, should be about the right size to slide onto the VB controller. I attached everything using hot glue, which is good for prototyping because it’s fast and easy to remove, but not so good when you actually need a strong hold. I had to re-glue these a couple times during testing.


Wired together. The voltage is what I expected it to be.


Glued together. Again, this fell apart if I was too rough with it. I’ll use stronger glue on the actual finished project.


Remember, I haven’t gotten to the part where I try to make it look good. At this point I still didn’t know for sure that it would even work.


It works! Next step is to make it not look like trash!

6 Replies

I wonder how long it would last on that sort of setup, since the battery you’ve made would be technically rated at 7.2V. It would be cool to see how it performs over a period of time and if the system is ok with that voltage, cause having a rechargeable battery pack would be sweet!

I thought they were rated at 3.7 each for 7.4 total. I’ll definitely measure the voltage of my “battery” when it stops powering the VB, and I’ll try to track how long it lasted. It’s been humming along great for about an hour of playtime so far. Whatever my results are, new 18650’s would perform better than these salvaged ones.

It would be neat to install some sort of charge board with a micro USB port on it, so I could either swap the batteries out, or just plug it right into my phone charger.

Oh maybe, standard Lithium Ion cells are 3.6V each, not sure about those specific ones. Either way, only .1V difference =P

It would be really cool to just be able to plug it into a USB for charge. Let us know how long you get out of your charge, I’m curious 🙂

Not bad! You should be able to find a charger+protection circuit on eBay, Banggood, DX, etc.

You can get empty USB battery packs designed to hold one or two 18650s, but the charger PCB is also a boost-converter designed to output 5V, which is not enough for the VB’s regulator. You might be able to modify the charger to disable the boost-converter, or modify the controller to send its 5V to the VB instead of the battery voltage. You would just hook the controller’s switch in series with the cells and the battery input of the charger PCB, hook the boost PCBs 5V output to the VCC line in the controller, and leave the VBat line going to the VB disconnected, bypassing the VB’s own regulator. You’d want to test it first to make sure the boost box can provide enough current to run the VB, but it probably will.

I can’t wait to see your “budget enclosure that doesn’t look like trash” 😉

Yeah, the VB will easily run off two 18650s. It has a buck regulator with the input specified from 6V-13V. A long time ago I gutted a battery pack and put in a 2S LiPo battery, and it worked fine.

The biggest problem IMO (as RP brought up) is related to the protection circuitry. The VB will run down to about 5V on the input, but if you run the batteries down to 2.5V per cell, they’ll be ruined.

You can do a hard cutoff at 3.0V per cell to protect them, but the low battery warning on the VB doesn’t show up until just below 6V. So, with the protection circuit, you’ll get no warning that your batteries are low and that the VB is about to turn off. You can power the +5V rail directly with your own regulator, but again, that doesn’t provide a low battery warning.

IMO, the best solution would be to redesign the controller circuitry to roll in the battery, charger, protection, status, etc. But it’s probably not worth it, since the VB isn’t exactly “portable”… I personally almost always run it plugged into the wall.

DogP

This is great info, thanks all!

I’ve been distracted with other things, playing off and on, not doing a very good load test on these batteries. but I’d better keep an eye on the voltage if it’s going to dip that low. Maybe I’ll slap on one of those voltage indicator lights or something to keep me aware of the voltage without tampering with the controller itself. I don’t want to tamper with the controller, I just want to play VB off 18650’s, as simply as possible. Hopefully I’ll have time this weekend to make some incremental improvements.

 

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