Scientists have long attempted to find materials to make batteries that are more powerful, but cost less to build.

In the United States, researchers are experimenting with sodium to see whether it can power much-improved batteries in the future.

Sodium is a soft, silvery metal. It is plentiful and found in seawater.

The most common battery used today is made of lithium ion. These batteries power everything from smartphones to computers to electric vehicles.

Researchers from the University of California, San Diego are attempting to build a new generation of batteries powered by sodium instead of lithium. The U.S. National Science Foundation is providing financial support for the experiments.

Shirley Meng is a member of the research team. “At a society level, I think people really think that a battery is a done deal -- like it’s (an) old subject.”

But Meng says the process of developing better batteries is still a work in progress. In fact, she says the energy density of batteries in use today “can still be doubled or tripled.”

The California researchers are studying lithium ion batteries, but in the next few years plan to begin testing new sodium batteries. Team member Hayley Hirsh says she looks forward to working more with sodium development in the future.

“We want to use sodium instead of lithium because it has different properties. And also, sodium is much more abundant."

Lithium is costly and not easy to collect because it is widely spread across many parts of the world. Large amounts of water and energy are also required to gather lithium.

But sodium is found in the world’s oceans, with a seemingly limitless supply. This would lead to much lower costs to produce sodium ion for batteries.

Hirsh says she is examining different ways to make batteries that last longer and can store more power.

“Right now it’s just in the lab and we're working on figuring out how to make it hold more energy and last longer so that it can be used in your phone, in your car or even to store energy for solar, for wind.”

Finding better ways to store more energy at a lower price has been one of the major barriers to developing more powerful batteries.

Today it is not really cost effective for power companies to use batteries. This is because it would cost hundreds of dollars per kilowatt hour to operate.

However, using sodium ion batteries could bring that cost way down. The researchers say it could then make economic sense for people to have storage containers at home to save energy produced by the sun or wind.

“They have solar on the roof. They could store the electrons during the day and use them at night,” Meng said.