The data here covers both electric only cars and those with some sort of range extender assistance. In all cases the car can be connected to an electric socket. In 2013, 203,800 such vehicles were sold in Europe where such data is supplied. In 2013 - the first year for data that I have - 33,600 were registered so things are moving.
Depending on how much assistance a government is giving determines how many are sold, along with how convenient recharging is. The fact is they are still not commercially viable without assistance. I would be happy to have an electric vehicle but cost and convenience in New Zealand means it's not an option - for now at least.
Norway has done so much to promote electric cars, they are the leaders in Europe in this. The UK is getting there while France and Germany are not as switched on. Sales slumped in the Netherlands in 2016 due to incentives being unplugged so not really a shock. Total sales increased 10%, which isn't that impressive.
Summary: For now sales are moving up but slowly. Battery cost, capacity and weight are hindrances but there are gains being made here. I'm not convinced that electric will ever be a major source of automotive propulsion but the jury is out on that one.
Data source: ACEA.
Text source: RayCee.