The 8BitDo Zero 2 is a tiny Bluetooth gamepad that's small enough to fit in a pocket or keychain to a bag. The controller is compatible with Windows, macOS, Android, the Raspberry Pi, and the Nintendo Switch and Switch Lite. Despite its diminutive size, 8BitDo claims the controller will last for 8 hours on a charge, which should take about 1-2 hours.
https://www.notebookcheck.net/8BitDo-s-tiny-Zero-2-Bluetooth-gamepad-now-available.449092.0.html