I combined this excellent arcade riser by @HGTelecom with a single 18650 battery shield. Now you can play your Neo Geo Mini with plenty of battery power, and pop in micro USB to recharge at any time. As a side benefit, this adds some weight to the riser which might make it a little more stable. I previously had modified my NGM with an internal battery mod, but this way is much more clean, using an easy-to-remove JST connector, and much more reversible, just tuck away the JST connector inside.
Free 3D file Arcade Riser with Battery Bank for Neo Geo Mini 🕹️・Design to download and 3D print・Cults
Complete Arduino-based 3D-printed Battery-powered Mini Retro Arcade Machine : 6 Steps (with Pictures) - Instructables
Free STL file Mini bartop : Neo Geo 🕹️・3D printing template to download・ Cults
Free STL file Mini bartop : Neo Geo 🕹️・3D printing template to download・ Cults
Free 3D file Arcade Riser with Battery Bank for Neo Geo Mini 🕹️・Design to download and 3D print・Cults
Things you will need:, Your 3d printed parts (Neo Stick Raspberry Pi / Neo Stick), 2 x Arcade joystick sets: 2 x USB 3.0
Neo Arcade stick 2 Player (Rasperry pi 4 joystick)
3D file Neo Arcade stick 2 Player (Rasperry pi 4 joystick) 🕹️・Design to download and 3D print・Cults
mini arcade riser 3D Models to Print - yeggi - page 31
Neogeo best 3D printing files・107 models to download・Cults
Neo Geo best 3D printing files・21 models to download・Cults