Will Ultra-Cheap Batteries Drive a New Roaring ’20s?

Humanoid robots everywhere, people wearing VR devices, and an EV boom

In a Model T, a country jaunt in the 1920s. Photo: Hulton-Deutsch/Corbis/Getty.

Batteries are very near a tipping point sought by entrepreneurs, tinkerers, and investors for a century and longer — a cut in average cost so low that electric vehicles can be profitably priced the same as their gasoline-propelled cousins. The coming price…