Battery + drinking water from ... seawater
Kyle Smith, a professor of mechanics and engineering at the University of Illinois, and graduate student Rylan Dmello published their studies on the production of electricity and fresh water during the operation of a sodium battery.
Researchers were inspired by sodium-ion batteries that contain salt water. In these devices, two compartments with electrodes are separated by a separator through which ions can move. When the battery is discharged, sodium and chloride ions - two elements of salt - are drawn to one compartment, leaving desalinated water in the other.
In a normal battery, ions diffuse back when current flows in the opposite direction. University of Illinois researchers have found a way to keep salt separate from water:
“In a conventional battery, the separator allows the salt to diffuse from the positive electrode to the negative,” Smith explains. “This limits the amount of salt that can be released. We put a membrane that blocks sodium between the two electrodes, so we can keep it from the part where the water is. ”
“We are developing a device that will use materials in batteries to remove salt from water with the least amount of energy, as much as possible,” Smith said.
The technology is interesting, since currently the most commonly used reverse osmosis (= expensive and energy-intensive process), although research has not yet reached the stage of practical experiments with sea water. Also, real impurities and pollution are not taken into account.