Battery technology could provide fresh water from salty seas

New York: The technology that charges batteries for electronic devices could help provide fresh water from salty seas, new research has found. "We are developing a device that will use the materials in batteries to take salt out of water with the smallest amount of energy that we can," said one of the researchers Kyle Smith, professor at University of Illinois at Urbana-Champaign in the US.

The most-used method, reverse osmosis, pushes water through a membrane that keeps out the salt, a costly and energy-intensive process. By contrast, the battery method uses electricity to draw charged salt ions out of the water, the study said.

The researchers were inspired by sodium ion batteries, which contain salt water, and they believe that the battery approach holds several advantages over reverse osmosis. The battery device can be small or large, adapting to different applications, while reverse osmosis plants must be very large to be efficient and cost-effective, Smith said.

The pressure required to pump the water through is much less, since it is simply flowing the water over the electrodes instead of forcing it through a membrane. This translates to much smaller energy needs, close to the very minimum required by nature, which in turn translates to lower costs.