Interchangeable battery in gameboy game cartridge?

[FlashyFrank]

Not sure if this is something that has been done. Seems like the battery I have is almost the same size as a Game Boy game and I the thought came to me that it would be pretty cool if the cartridge was the battery and you could swap it out real fast just by popping it out and popping a fresh one in. Thoughts?

[Helder]

Not unless you have a high capacity capacitor in the power line to hold a little charge while you do so. Likely better off have a switch to switch between the 2 with capacitor mentioned so it smooths any powrr spikes and also maintains a charge while switching.