Not really, the voltages don't match up, would need to use a voltage regulator.

I know what you are saying, lipos are way cool, but fortunately it not a big deal with a DX3R. Its already really light and the batteries last a long time. I have cheap 2600 nimhs, have only charged them twice since March, both times mostly out of guilt, they were still going strong. Racing 2 classes weekly plus some bashing.