Actually it might, no, probably will increase flight time with "deep cycle" and a fully "saturated charge" by how much, that depends on the percent of full charge the OEM charger is charging the OEM Li-Po's to now - but at what cost!
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As is, all OEM Li-Po batteries using an OEM Li-Po battery charger never charge to 100% capacity and for good reason (life of the Li-Po can be reduced when charge saturation brings it to 100% charge). Despite the DJI Li-Po showing full green after charging it is not a 100% charge and for the reason stated previously.
So is this unit a good choice? Maybe and probably as DD states "keep your batteries in top notch condition" while in service - but overall life is likely decreased with the saturation charging time added.
It will give you a proper discharge down to 8% prior to kicking into the charging process and that is a good thing for extended overall life expectancy (I know very contradictory when a 100% charge reduces life but the discharging (when used) to 8% prior to charging will extend life).
So IMO it's a trade off between overall life and extra flight time from a 100% charge. This charging unit does offer plenty of convenience and time saving for charging everything at once and multiple batteries - so that's another plus for it. Considering all that it offers it is worth the $$, but only if you are a serious flyer, as in daily multiple flights for commercial use.
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