Game Gear Cartridge Battery Replacement

I bit the bullet and had my childhood game gear refurbished by navyvet2015 (on eBay). One of the games that I picked up again was Shining Force - The Sword of Hajya, which I was pleasantly surprised to find had a game save mechanic/technology. I had forgotten how brutal the 90's games were from my childhood.

I unfortunately discovered that the save games were lost whenever I removed the cartridge and played a different game, which lead me to research and find that there were internal batteries on some of the game gear cartridges.

Other than a random Reddit post I wasn't able to find any more information on how to replace the battery, so I hope someone finds this useful.

Tools Needed:

• 3.8mm Gamebit screwdriver/bit - I purchased a set of gamebit screw drivers
• Soldering iron and thin solder
• CR2032 battery with pre-welded solder tabs (Note: Look for tabs that match your board layout) I purchased this exact one (pictured below) because I couldn't find one with pins that were 90 degrees apart (only 180). If I were to do it again, I probably would purchase the other versions with the more robust solder tab ends with holes. 

Step 1: Remove the backing screw from the game cartridge. Being careful, pry the top and bottom apart. to expose the original battery to use as a reference.

Step 2: Slowly and carefully fold the negative (flat) side tab making a crease at a 45 degree angle (which will make a 90 degree bend once fully folded). Bend the positive (rounded) side tab pointy tip where it will lay flat when the battery is on the negative (flat) side.

Step 3: De-solder the original battery from the game board. Be careful to use minimal heat to avoid lifting the copper traces from the fragile 30-year-old PCB.

Step 4: Solder the tabs of the new battery to the board being careful to keep the solder on the original trace and not to use too much heat to damage adjacent circuitry. Warning: Never solder directly onto a raw coin cell battery, as it can be a fire hazard. Only use cells with factory-welded tabs, and ensure you have a fire extinguisher nearby as a precaution. See below before and after pictures:

Step 5: Reassemble the game cartridge and plug it in and pray it works!

Please drop a comment if you found this useful or if there are any suggestions/updates/corrections. It makes my day when someone out there reads and finds one of my posts particularly helpful.