Tohoku University in Sendai, Japan enjoys a fine reputation for research excellence in a wide variety of fields. A team there published a report on April 3, 2024 concerning the use of paper in thin wearable devices. They claim their paper battery prototype reduces dependence on metal and plastics, and is simpler to recycle. We investigate what potentially sounds like a winner.
The Paper in the Recyclable Battery Prototype
Paper is thin-sheet material resulting from compression of moist cellulose fibers from wood, rags and grasses. An ancient Chinese visionary came up with the idea in the second century before the common era, whereafter it spread throughout the world as a storehouse of knowledge.
Digital media are rapidly replacing paper as a vehicle for storing information. In parallel, paper is finding new uses offering more environmentally-friendly ways to do familiar things. The researchers explain how their paper battery prototype drew inspiration from photosynthesis in plants as follows:
- Plants harness solar energy to synthesize sugar from water, and carbon dioxide from the ground.
- While their battery utilizes magnesium as a substrate to generate power from oxygen and water.
More About the Tohoku University Magnesium-Air Battery
The team at Tohoku University in Sendai, Japan first bonded magnesium onto paper. Then they added a cathode catalyst and gas diffusion layer directly to the other side of the paper.
Their magnesium-air battery with neutral electrolyte activated by water, achieved an open circuit voltage of 1.8 volts, a 1.0 volt current density of 100 mA/cm², and a maximum output of 103 milli-watts / cm².
“Not only did the battery demonstrate impressive performance results,” corresponding author Hiroshi Yabu explains. “It operates without using toxic materials. Instead it uses carbon cathodes and a pigment electro-catalyst that have passed stringent assessments.”
More Information
Paper Batteries That Can Change Shape
A Paper Thin Battery for Tight Places in Space
Preview Image: Overview of Paper-Based Battery
