fundamental feature of this and all other electric vehicles is the central electron storage system. Lighter weight lead - sulphuric acid batteries than the conventional accumulator type are being developed and there is plenty of lead left in the world.
For example, if we take the current number of cars at 500 million (I think the total number of road vehicles in the world is around 700 million - that's cars, lorries, buses, everything, but let's just stick to cars), we would need about 150 kg (per car) x 500 x 10*6 = .15 tonnes x 500 x 10*6 = 75 million tonnes of lead.
I believe there is certainly 1.5 billion tonnes of lead in known deposits, so there is plenty to go round.
Lithium ion batteries (the current favourite) are costed in energy terms at 2 kg of lithium per kwh of battery (specific energy). The PHEV is rated at 9 kwh and so each car would need 18 kg of lithium. Hence, 500 million PHEV's would require:
18 kg x 500 x 10*6 = 9 x 10*9 kg = 9 million tonnes of lithium.
The entire world reserve of lithium ( accounted in the form of lithium oxide, Li2O) is 10.74 million tonnes, which contains (worked at an abundance of 92.5% lithium-7 and the rest lithium-6):
2 x [(7 x .925) + (6 x .075)] x 10.74 x 10*6/2 x [(7 x .925) + (6 x .075)] + 16 = 4.98 x 10*6 tonnes; call it 5 million tonnes of lithium.
Obviously there is not enough!
We could argue naively that there is sufficient to propel 278 million cars (i.e. around half the world's fleet) adapted into PHEV's, but this would conflict with the interests of nuclear fusion (if they ever get it off the ground) which could only run for about 300 years, and so it would be a question of lithium to make electricity or to store it inside cars to get any actual mileage from it!
Since, as I have argued before, nuclear fusion will not come to our aid before oil and gas run out, we can forget about this point, but I make it to stress that the same (limited) resources are often impacted upon competitively by different kinds of technology and it is as well to be aware of the fact.
If we wanted fully electrically powered cars, with a power demand of 36 kwh (over the 9 kwh reckoned for a PHEV), then we would need to reduce that figure by a factor of four (36/9) leaving us with just under 70 million cars in the world. These figures are an absolute maximum, as of course, there are many other uses for lithium batteries, eg. heart pacemakers, pocket calculators, computers and cameras etc. etc.