New Foam Batteries Promise Fast Charging, Higher Capacity

Affordable, lightweight, and versatile, batteries made of porous materials could soon transform energy storage.
Despite billions of dollars in investment and the launch of several high-profile startups, the energy sector still faces a fundamental and seemingly insoluble challenge: it’s very hard to store lots of power in a way that’s compact, long-lasting, and low-cost. A growing number of researchers are hoping to solve that with what are known as three-dimensional batteries, which can take several forms but tend to have porous, sponge-like structures, as opposed to the traditional “2-D” form: thin layers of metal in a liquid electrolyte solution inside a box (see “A Stretchable, Bendable and More Powerful Smart Watch Battery” and “Batteries: Cheapest Form of Grid Power?”).