I think we are almost there, plenty of self charging hybrids around. When I first encountered them I couldn't understand why they were built without the ability to plug in. It's all about battery management, get the computer to control how and when charging occurs and you can get much better battery life, but that's changing as batteries are developed. In this way they were saving more direct carbon emission per mass of battery metals over the vehicle life than contemporary EVs although that depends heavily on how you generate the electricity used to charge.The whole issue of EV's is that fundermentally it sounds a good idea on paper but rather than make the huge jump from ICE to EV which is just far to big a jump we need to get there in logical steps. The current idea is just going to cause too many issues with our electrical infrastructure, refineries and jobs so make the first step a big reduction in the consumption of petroleum based fuel by going hybrid but one where there is no mechanical link from the ICE to the wheels, rather the ICE drives a generator much like a locomotive. Now you can have far more fuel efficient ICE's because they are there only to keep the battery topped up and maybe provide extra power when needed. Now no issues with home chargers, queueing to access a charger and then waiting for it to charge. Now you have a breathing space in which technology can work towards the all electric EV.
I'm not sure about the engine / generator combination, it must be efficient when used in locomotives or they would not be doing it, I suspect that this is connected to the need for a locomotive to have significant weight and that it might not be the best way for road vehicles - that last bit is opinion not fact, if there is anyone out there with knowledge I'd appreciate the education