I'm looking for some general advice and/or specific recommendations for a project I'm working on - animatronic Halloween decorations. I'm fairly new to Arduino and hobby electronics in general, so bear with me!
The general premise is that I'll be using a Arduino Uno with a DMX Shield (RS485) and ESP8266 connected to either a hardware or software (USB dongle) stage lighting controller. Upon receiving the appropriate DMX signals on the designated channels from the controller, the Uno will transmit over the ESP8266 to multiple remote Arduino Nano's with their own ESP8266's. What each one does, I'm still planning, but I know I'll at least be using some small motors (whether DC, stepper, or servo) and perhaps some small speakers, too. But because these units will be remote and living outside for the day of the event, I'll need to be operating them on batteries. I need to have them fully awake and ready to receive the WiFi signal to then actuate the motors and speakers, since this will be happening in sync with other DMX-controlled stage lights. I anticipate that I'd like to have them operational for about 45 seconds at a time every 10-15 minutes for about 8 hours.
So finally, my question is: What would be the best battery configuration for these remote units?
Size and space are fairly open as long it's smaller than a 12V car battery. And I'm more than willing to hit Buy Now on the South America River for some additional parts. I do have a few buck step-down converters, plenty of AA and D batteries and holders (my first guess of a solution) and a few 7.2 V RC car batteries. LiPo's/18650's terrify me for this kind of stuff, but if that's the best option, I'll consider it.
Good advice is greatly appreciated (and I'll probably need to follow up for specifics!)