Scientists Invent Battery Made of Paper

Scientists have developed a water-activated, disposable, paper battery, according to a proof-of-concept study published in Scientific Reports The developers believe that their invention could be used to power a variety of lowpower, single-use electronics, such as smart packaging, environmental sensors and medical diagnostic devices, thereby reducing their environmental impact.

The single-cell battery consists of one square centimeter of paper treated with salts. One side is printed with ink containing graphite flakes, which serves as the positive terminal, and the other side is printed with ink containing zinc powder to create the negative terminal. Another layer of ink containing graphite flakes and carbon black is applied over that, linking the battery’s positive and negative ends to two wires secured by wax.

When a few drops of water are added to the paper, the salts dissolve, releasing charged ions that spread across the paper to activate the battery. In tests, researchers were able to reach a stable 1.2 volts. (The voltage of a standard AA alkaline battery is 1.5 volts.) The battery’s performance decreased significantly after an hour when the paper dried. However, after two more drops of water were added, the battery maintained 0.5 volts for an additional hour.

Exploring the Doomsday Glacier

Roughly measuring the size of Florida, the Thwaites Glacier is one of the most rapidly melting ice formations in Antarctica, having retreated more than eight miles since the 1990s. Scientists refer to it as the “doomsday glacier” due to concerns about its collapse, which could raise global sea levels by more than a meter, causing devastation along coastal cities and communities.

According to two papers published in the journal Nature, researchers are learning more about the driving forces behind the glacier’s rapid retreat, thanks in part to a robot deployed through a 600-meter-deep borehole in the glacier. Although melting has increased beneath the ice shelf, the current melt rate is slower than many computer models had estimated. A layer of fresh water between the bottom of the ice shelf and the ocean below slows the rate of melting along flat parts of the shelf.

Scientists discovered that the melting had produced a stepped topography across the bottom of the ice shelf, resembling a staircase, as well as cracks in the ice where rapid melting was taking place. “Our results are a surprise, but the glacier is still in trouble,” says Dr. Peter Davis, oceanographer at the British Antarctic Survey and lead author of one of the papers.