The future is not predictable, but if you're Ray Kurzweil , you can make an educated guess. Known for his wild thinking on any number of topics, Kurzweil was the keynote speaker at the opening of the 2015 SAE World Congress today. His talk, called "The Acceleration of Technology in the 21st Century : the Impact on Business, the Economy, and Society," was a broad look at biotechnology, how humans will live for a long, long time, and exponential growth.Kurzweil calls this immense rate of change the " law of accelerating returns " and the short version is that there's a big difference between a linear increase that is simply one step higher than it was before (so, 1 to 2 and then to 3 and then 4) and an exponential doubling (1 to 2 to 4 to 8). Sometimes when technology is changing, people think it's the first kind of increase, but it's really the second.Despite speaking at an automotive conference, Kurzweil barely touched on car stuff. He did say autonomous vehicles will get better, but spent most of his talk discussing computers and medical breakthroughs. So we asked him a car question.Responding to a question submitted by AutoblogGreen about electric vehicles and hydrogen fuel cells , Kurzweil said that batteries have made modest progress, but have not seen the exponential growth that will bring radical transformation yet."I think we will see that when we get to the more mature phase of nanotechnology," he said. "Biotech is here. It's transforming medicine. Nanotech is not quite here. It's still 10-15 years away." And the big gains will be realized "when we can actually manipulate matter and energy at the atomic and molecular level. There are already very exciting designs for energy storage that will be very transformative, that are enabled by that."But the most intriguing bit of futurespeak that Kurzweil offered was his vision of a completely new kind of fuel cell. "I know one company that is creating microscopic-sized fuel cells and you can put millions of them in a very small space and create very inexpensive, very powerful energy storage with a very high energy-to-size ratio. But these are futuristic. Nanotechnology is still, I'd say, on the order of a decade away. So that will transform all kinds of electrical devices, including electrical vehicles. Fuel cells that are actually microscopic in size will be a part of that picture." Whatever company he's talking about – maybe he's thinking of this – we're totally into learning more.