[lioeters]

The Ox64 takes 3.3V power. That's the same as ESP32, which is in a similar category of "system on a chip". From what I read, two AA batteries in a series can supply that (~1.5V each) but their total current is weak (50 mA) compared to what the ESP32 requires, 300~500 mA. This type of Alkaline batteries is also rather unsuitable due to the profile of how the voltage is reduced as it discharges. I imagine the same applies to Ox64, that AA batteries won't work at all or only for a short time.

Typically recommended are lithium iron phosphate (LiFePO4) or lithum polymer (LiPo) batteries, both of which have higher capacity, better discharge profile, and can be recharged (the latter while the device is in operation).