What is the ideal battery technology to keep this drone working as long as possible?
Flight duration is a complex combination of the weight of the drone (the lighter the better), the efficiency of the fans (larger diameter is usually better), the efficiency of the motors and the capacity of the battery.
AFAIK LiPo cells have the lowest weight for a given energy capacity. They need to be managed carefully as they can explode or cause a fire if mistreated.
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