Kadin2048
Yes, there is always the chance of one pack not performing as well as another hooked in parallel. We see this situation rarely happen in Polyquest brand batteries due to their very consistent cell manufacturing and matching prior to assembly of their packs. There are low voltage cut-off devices already on the market that will prevent packs from being over discharged and devices are sure to come that will prevent individual cells from being over discharged. The thing is not to run the whole duration and bring the heli down. The other thing you can do, if weight is permitted, is to use a little higher capacity battery so you do not discharge it too low and extend the cycle life of your packs. I cannot reply to the diode scenario but I know diodes have a max current rating to them and don't know if they can withstand your present discharge rate.
hope this helps
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