Graphene, applied in a sodium-ion battery may herald inexpensive alternatives to lithium-ion cells. Scientists are exploring ways of making batteries not only more energy-dense, but also less costly. Sodium, a primary ingredient in table salt, is one possibility. It’s also abundant without too much effort required to find it. On the other hand, easily-obtainable lithium may become in short supply at a time when the world is clawing its way into the earth searching for more. Sodium is the sixth most abundant element on earth, making up about 2.6 percent of the planet. It’s never found free in nature, but always as part of something like the salt (NaCl) one can see it crusting over from evaporating bay water near Moffett Field, California, or in the Great Salt Lake in Utah. New Atlas reports, “These sodium-ion batteries would function much like today’s lithium-ion batteries, generating power by shuttling ions between a pair of electrodes in a liquid electrolyte, but as …