In message . com,
Boltar writes

I can't see battery power being useful for more than a mile or so

The new Rome trolleybuses run for over 10km on battery power.

and in hilly areas I suspect its a non starter - literally.

I haven't been to Rome since the new line opened, but in general terms
Rome (on its famous seven hills) is not as flat as most of London.

--
Paul Terry