Australian researchers claim they have developed a battery that can keep a smartphone charged for five days or power an electric car for 1,000 kilometers (over 600 miles). If the technology comes to be used widely, it would represent a significant breakthrough in the hunt for greener, more efficient energy. The team from Monash University in Melbourne says the lithium-sulfur battery it has created is the "world's most efficient," and can outperform traditional batteries by four times. The researchers said they are "on the brink" of commercializing the innovation, and touted its benefits for...