this is possible. YOu will need to create your own balance Y adapter. I believe Reedy is going to come out with there own Y adapter. 2 other manufacturers I asked about it however would not make one do to liability issues they stated.
Push comes to shove, if you are not comfortable with an adapter, go with the Hyperion Duo (version 1 or 2, with v1 being cheaper to buy). It will balance charge lipos together as one pack.
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< Durango DESC410V2, DEX410V5>