100 kg of fuel and 50 kg less on the engine weight allows for a lot of batteries. Not sure what is the flight time, but if someone can help with energy density we can calculate the exact number. I wildly guess it is more than 1 hours, but definitely less than 6 hours.
Later edit: I did some calculations, the result is less than 30 minutes.
Not as bad because of the higher efficiency of electric engine. But yeah, 1 hour or so.
One hour is quite enough for taxi-type and drone delivery.
Also, you could use structural batteries, which would substitute for part of the plane structure.