we had thermodynamics lecturers who lauged at the notion that one day, internal combustion engines would be so efficient that we'd struggle to get enough waste heat out of them to work the heater!
At school in the early 90s I had a Physics textbook that confidently explained that if a petrol engine was more than 25% efficient then it would melt the cylinder block...
Re. the laptop batteries, I am constantly doing all the things you shouldn't do with a laptop and I have not noticed any degradation of performance in the 2-3 years between laptop replacements. I'm talking partial recharges, running it dead, leaving it on the docking station for a week etc. 5 days a week. I've got a 4-year-old Nokia phone that I took out of a drawer to use at a party and found that the lithium battery was still perky.
I think that lithium batteries are as much about luck-of-the-draw as the actual chemistry.
I still want an electric car, but the current crop only make financial sense for company-car users or those who live outside the congestion zone but need to drive in central London (my view, not necessarily correct ). For my 10,000 miles a year, all outside the congestion zone and mostly on motorways then it would only make sense if I could lease one for the savings I would make on petrol, but I doubt they would be leasing a £20-£30K car for ~£100 a month...