That's completely false. I might have said, "Look at a basic mousetrap 30 years ago. Now look at one today. Identical." What's missing is any examination of the alternatives. 30 years ago, there weren't any NiMH batteries, or commercial lithium-ion batteries (the latter were under active development), but they're now the primary power sources for portable devices, and lithium-ion batteries power the Tesla Model S.
> I don't think conventional batteries can improve all that much more.
And I don't think conventional thinking can improve all that much more. But I have high hopes for unconventional thinking.
"When a distinguished but elderly scientist states that something is possible, he is almost certainly right. When he states that something is impossible, he is very probably wrong." -- Arthur C. Clarke