Scientists have discovered an intriguing way to generate electricity using a mixture of ordinary ice and salt. Simply freezing the salt water and then slightly bending the ice produces an electric current. This phenomenon, known as the flexoelectric effect, holds promise as a foundation for environmentally friendly energy.
Experiments have shown that a small cone of salt ice, smaller than a grain of black pepper and containing about 25% salt, can generate a voltage of about 1 millivolt. Connecting 2,000 such cones together can generate about 2 volts, enough to light a small red LED.
The authors froze salt water in silicone molds and created two types of samples: cones and curved "beams." The results showed that the cones could withstand greater pressure and generate more energy.
This is because a thin layer of salt water remains within the salt ice. When the ice bends, a pressure differential is generated, causing the liquid to move, and with it, positively charged ions, generating an electric current.
Currently, practical applications are limited. For example, charging a smartphone requires a block of salt ice measuring several dozen square meters. However, in the future, such structures could be used to power sensors or small devices in cold regions.
