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Power heltec v3 with NIMH batteries?
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A community to discuss Meshtastic (https://meshtastic.org/docs/introduction)
My guess is that you could power the board, but charging will end in disaster.
Nimh isn't as energy dense as li-ion as I recall? So an 18650 is probably a better bet.
Yeah my plan was without charging. But I found another solution anyways :)