Today’s electric cars are money losers, despite government subsidies. Even then, when priced far below their subsidized cost, they appeal only to tiny niche markets. As the Trends editors have explained, this won’t change until there is a change in the economics of batteries. Economies of scale will help, as will component redesign. But a better answer may involve so-called flow batteries. What are flow batteries? Why are they increasingly attractive for a wide range of applications? What are their implications for both intermittent energy and transportation? We’ll show you.