I understand that I can use 4AA batteries and a step down module to get 5V and power the Pi, however briefly. However, now I'm getting real outrageous and want to trying powering the Pi from just 2AA, even if just for 5 minutes.
The deal is, I have a Raspberry Pi working as my dash cam and powered by a USB cord, but I'm guessing the cord may be easily yanked out if I'm in an accident and my video would get cut off mid recording and corrupt the file (it saves in 10s video segments). However, I would like to have 2AA within my enclosure that take over power supply responsibility in the event main power is lost. I know 4AA is much easier, but takes more room. Instead, I want to use 2AA with this DC-DC step up module. As far as I can tell, I can use this module to change my 2AA batteries into 5V.
Am I correct in my understanding? Let's say the batteries are 1500mAh and in series provide 3v, so 3v/5v=0.6 * 0.85(inefficiency) * 1500mAh = 765mAh, which should power the Pi theoretically for nearly an hour, but I'd be happy for 5 minutes. Please tell me if this will work. Thanks!