Bruce Gellerman for WBUR:  The ability to store energy promises to revolutionize the way we generate, transmit and use electricity — making renewable sources such as wind and solar cheaper and more dependable.  
Massachusetts is one of just three states requiring electric utilities to build battery facilities in the future.  A company in Marlborough believes it literally has the next hot technology in energy storage: molten metals.

About 10 years ago, MIT materials chemistry professor Donald Sadoway began wondering what it would take to make a better battery. One that could store huge amounts of energy, charge and discharge rapidly and operate reliably for decades. Of course it would have to be safe: non-toxic and not explode. And, oh yeah, inexpensive to make.

Sadoway stared at the periodic table of elements and had a "eureka" moment — build batteries out of liquid metals.  Full Article: