Distributed Generation , Mar. 2017, by Laura Sanchez.
http://foresternetwork.com/weekly/distributed-energy-weekly/lithium-sulphur-the-next-energy-storage-superstar/

"Lithium-ion batteries power many modern devices from cell phones, to cars, laptops, and a multitude of portable electronics.  But their power density is less than ideal. And there appears to be another, perhaps more promising energy storage option on the horizon: lithium-sulfur batteries."