These planes are hybrids - they use a turbine to charge batteries and power the EDF engines. I suppose the batteries are used for take off and cruise flight is mostly powered by the turbine (that doesn't have to be powerful enough for takeoff). Landing, again, can be purely electric.

It could, but it will complicate the design a bit since you have to have very easy and quick access to the battery which means a new piece of machinery on the ground to swap the battery and exterior access hatches.