I have been hearing about electric cars since the days of the second oil crisis (1979 - 1980), when we were told with confidence that "within two years, the electricians will be making the cars." Older people report that similar predictions about electric cars were being made over 60 years ago. For a time, I worked in the testing laboratory for a major battery manufacturing company (Century Yuasa). At that stage, much research was being carried out into alternative types of batteries, and high hopes were being held for the possibilities of the fuel cell. Twenty odd years down the track, though, it is still the lead-acid cell that proves to be the most practical one - albiet in a more refined form (i.e. maintenance free).
Battery powered forklifts excepted , I will believe battery powered cars taking over from those with internal combustion engines only when I see it happen.
(Oh, and I did forget, the buggies used for mobility by some disabled people . I won't be trading my car in for one, though - not just yet!).
Crystal ball gazing about such matters as alternative energy sources has proven most difficult, and caution is advised (look at New Zealand's much-hyped synthetic fuel project of the early 1980s - sold off by fire sale after being painted white and adorned with a trunk!).
Bill.
Bill.