I have often wondered if, except for a few specific users (I remember, from the 1960s, the electric milk float) if battery technology will ever offer sufficient energy density and longevity for transport that is sufficiently robust that you don’t worry about getting home if it starts to rain and you need to turn on the wipers and lights and turn-up the heater! Oh and then there is the potential for thermal runaway (ie “fire”) just think Boeing 787 Dreamliner but there are alternatives on the horizon: http://player.vimeo.com/video/51873011
Like electric cars those powered by fuel cells also result in questions about where the electric comes from – hydrogen and oxygen may be all about but methane, fossil fuels or even water must be separated and this needs electricity! Also Hydrogen is still not as energy dense as petrol or diesel so more volume for the fuel tank or a shorter range.
However, work is underway; see, for example, http://www.technologyreview.com/view/510416/ford-daimler-and-nissan-commit-to-fuel-cells/?utm_campaign=newsletters&utm_source=newsletter-daily-all&utm_medium=email&utm_content=20130129
If sales are a relevant measure then there is a long way to go. On the 23rd January the FT reports the UK’s Society of Motor Manufacturers and Traders as giving 2,044,000m for the number of car registrations in the UK in 2012 of which 25,770 hybrids and 2,237 were “grant eligible” electric. But all of these figures are up on 2011 and in the case of “all electric” by nearly 2000% since 2010. (Chris Tighe, Nissan cuts price of all-electric Leaf)
And once we have the fuel sorted out and we are all buying electric or fuel cell powered cars just how will the government get the tax it now gets from petrol and diesel? Of course we could all drive personal “slipper” cars on flat circuits and forgo our desire for dramatic acceleration. Then over 15,000mpg(UK) (3836 km/l) appears possible: http://www.youtube.com/watch?v=fPcAH1kupug