In this guide, I'll show you how to build and install a USB-C rechargeable battery on your Game Boy Advance. This USB-C GBA battery mod is very inexpensive and should take you around 30 minutes to complete.
Lately while testing GBA flash carts I've started to think more and more about battery life. I usually use a GBA SP with the IPS mod installed, but I prefer the feel of the original Game Boy Advance and it's the model I fondly remember as a teenager. The original Game Boy Advance didn't have rechargeable batteries and I use one with my favorite, but it uses a lot of powerEZ-Flash-Omegait quickly became an expensive proposition, especially when I started installing an IPS screen on this model. Let's start our GBA USB-C Mod.
What do we need to install this mod?
To install a rechargeable battery in your GBA you will need a few things:-
3,7 V LiPo-Akku(I use 1100 mAh of size 47 x 28 x 7.8mm)
USB-C charging board(I'm using a USB C TP4056, you can also use the micro USB version)
a diode(I use a 1N4001 rectifier diode)
Tri-wing and Phillips screwdriver
Some cables (or can be salvaged from any old cable)
Soldering iron and a small amount of solder
electrical tape
Optional: drill with 4 mm drill bit or Dremel
How to Install GBA USB-C Mod Battery
First, let's make sure our GBA is working properly. This is especially important if you bought it on eBay. It would be a shame to complete the mod only to make it useless. Once confirmed to work, turn your GBA over and remove any installed batteries.
With the batteries removed we can size the battery compartment. The battery type I chose almost fits, but it fits better if I remove some of the plastic in the battery compartment.
Before we cut plastic, let's start with disassembly. On the back of the Game Boy Advance there are 6 tri-wing screws and a single Phillips screw to be removed in the bottom battery compartment.
With the screws removed, you can easily detach the back of the GBA from the front half. We want to focus on the battery compartment for now, so put the front half of the GBA with the mainboard aside. To make room for the battery, I remove the small piece of plastic on the bottom that acts as a divider for the AA batteries and the part on the right. I use a small pair of knives for this. Once the plastic is cut it might be worth taking off the old GBA battery clips, we won't be needing them anymore and this frees up extra room for us to work.
Now we can see if our battery fits. You can use any type of battery for this mod, just make sure it's 3.7V and fits in the battery compartment. Mine fits perfectly with plenty of room for extra cables and for the USB-C charging pad. The internal dimensions of the Game Boy Advance battery compartment are 51 x 30 x 14.6mm, with some modifications you could probably fit a slightly larger battery, but this would require cutting more of its shell.
Next we want to remove the battery clips that connect to the GBA motherboard. To do this, we must first remove the motherboard from the case. The motherboard is secured with three Phillips screws that need to be removed. There is a brown/copper ribbon cable on the motherboard that supplies power to the display. We need to gently lift the tab on each side to release the ribbon from the logic board. Once the circuit board is detached, lift the main circuit board and set the screen halfway to the side.
With the motherboard free, we can finally remove those battery clips. I recommend using a K soldering tip if possible, if you don't have one your regular soldering iron will work just fine, but you may need to solder longer to melt the solder completely. Peel off the two solder bumps and use tweezers or pliers to pull the battery post down. (Be careful, they get hot!)
If you're having trouble with solder bumps not getting hot, try adding new solder, which should help with heat transfer.
Now let's prepare our load plate. You will notice four paths at the top of the board that need to be filled with solder. Turn the load plate on its side and fill the following spots with solder:-
'SALIDA+'
'B+'
'B-'
'FOR A-'
It may help to put a little flux in the tracks to improve adhesion, but it is not essential.
Now the wiring here is pretty simple, the 'B' is for battery where we will solder the battery wires and the 'OUT' is for the output that will go to our GBA motherboard. Cut off the top clip of the battery cables.
Solder the positive wire to 'B+', usually red, and the negative wire to 'B-'
Put the battery and motherboard aside for a moment and grab your GBA motherboard. Turn the board over so we can see the underside of the battery posts. Cut two pieces of wire, preferably one red and one black. This needs to go from the battery terminal points to the middle of the battery compartment and a little further to connect to the USB-C charging board, I used around 6-7cm of cable. Solder the red wire to the top (+) battery post and a black wire to the bottom (-). Then slide the newly soldered wires through the case and see how much room is left to play with as shown in the image below.
Solder the black wire from the GBA motherboard to the 'OUT-' point on the USB-C charging board. Take your rectifier diode and cut off the legs, you want to solder these to 'OUT+'. I decided to turn mine to the left to better fit the battery compartment. The diode should have the strip facing away from the charging board so if you are soldering the red wire from the Gameboy Advance motherboard to the other leg of the diode, consider insulating it with electrical tape. Now we can test if our battery mod was successful. Connect a USB-C charging cable to the board. If everything is ok, the red LED on the charging board will illuminate to let you know the battery is charging.
To ensure the Game Boy Advance USB-C Battery Mod is working properly, gently turn the device over and slide the power switch to the on position. If everything is working, the green Power LED on the GBA motherboard will be lit and the startup sound will play as long as you have the volume turned up.
Now that everything is working, let's put our board in the battery compartment. Personally, I will hold my USB-C charging pad in the center as in the image below, but you can drop it in any direction you like.
The reason I chose the position is so I can eventually drill a small hole for the charging port. This allows you to simultaneously play games and charge your GBA via USB-C, which is not possible on a standard model, even with rechargeable AA batteries.
I will update this guide shortly after posting the battery case. The best way to do this is to line up your USB-C charging pad where you want to mount it, use a 4mm drill to drill a hole in the center and the USB-C slot with a file to finish off a nice finish To hold the panel in place you can use masking tape, hot glue, or two-part epoxy.
In terms of battery life, with aAGS-101 backlit viewfinder installedThe console draws around 80mA, so the 1100mAh in this GBA USB-C battery mod I installed should last around 13 hours and 45 minutes on a single charge. With any battery type, there is always some waste in terms of actual battery life; So we're more likely to see a total playtime of around 11 hours on a single charge. You'll know when your custom battery is charged when the blue LED lights up.
