There are a few flashlights that have USB PD power bank functionality and also run on 18650 or 21700 rechargeable, replaceable Li-ion cells. I bought a Loop Gea

There are a few flashlights that have USB PD power bank functionality and also run on 18650 or 21700 rechargeable, replaceable Li-ion cells. I bought a Loop Gear SK05 Pro to replace Anker power banks for this use case.