actually, you would need some 300zx rear end or such to convert it, and possibly having to reconstruct the center tunnel unless the car was made in awd or rwd configuration.
It's somewhat of a heavy car thoo, but may allow more weight. What happens is that you cannot make it heavier than the original weight + payload else it may not be legal in you state/country.
But since its a nissan, a whole lot of transmissions are advailable as well as rear ends. It IS possible to convert it, but its not for the faint of heart.
Im in the process of designing a AC motor drive for EV, so who knows i might offer kits to built yourself one day
edit : I may have misunderstood you so ill answer the question the second way i saw it. It is not more difficult to make a fwd ev than a rwd one. Electric motors are small, and most engine bays allows for some more widht. I do have the inpression the i30 is a automatic, that would have to be changed thoo.