I recently installed FunnyPlaying's rechargeable battery pack in my Game Boy Advance (Ultimate GBA ITA TFT LCD Mod)! : r/Gameboy
Game Boy Color Gets A Rechargeable Battery | Hackaday
Rechargeable Battery for Nintendo Game Boy Advance Systems + Screwdriver, 2- Pack - Walmart.com
The Ultimate Heavily Modded Game Boy Advance (IPS LCD, Audio Amp, Overclocking Control, Clicky L & R Buttons, and Rechargeable Battery Pack Mods) : r/Gameboy