Help with battery supply for Sound Project

Hi tech mates,

I’m making an RFID triggered sound project and I need help with selecting a rechargeable battery supply for it. Through my research, I need the following core components:

Adafruit METRO 328
Adafruit PN532 NFC/RFID
Adafruit Wave Shield

I then need an amplifier and speaker combination.
I’m deciding between these two options:

Stereo 3.7W Class D Audio Amplifier
Speaker - 40mm Diameter - 4 Ohm 3 Watt


Stereo 20W Class D Audio Amplifier
20W 4 Ohm Full Range Speaker

Does anyone have suggestions for a rechargable battery power supply for these two options that will also power the core components (Metro,RFID & Wave Shield)?

Thanks for your help,

Hi Ben!

This will be largely guesswork, since I didn’t find any information on the power draw of the RFID reader and the Wave Shield.

Its safe to say that the speakers will draw the most power out of everything, and that the controlling hardware will draw somewhere between 200mA and 1A (with 1A being very unlikely, but lets be generous with our estimates)

This battery will power the small amp and speakers for perhaps 2+ hours:

for the larger amp, you will need a larger battery. I’d suggest these: