Going all electric in one leap would never be acceptable, and carrying two types of engine would be hopelessly inefficient in terms of weight and drag.
That's not what we're being told about electric hybrid cars.
The electric motors on a hybrid car can be small and light. However, on an aircraft you cannot get away from the fact that you need r*ddy great fans to move all that air - presumably much the same size as the ones we have now. While these could be quite a bit lighter than a conventional turbofans they will still have a lot of frontal area.
Hence the only solution would be one for the kerosene and the batteries to drive the same fan. A true hybrid engine.