Today's star of the show: the electric eel
Many devices, such as heart pacemakers, are implanted inside the human body for medical purposes. Engineers want to improve them and create new ones. Besides being made of materials compatible with our bodies, it would help if these devices were soft and stretchy, like many natural body parts are.
Soft stretchy mechanical and electrical parts could also be used to make whole soft robots with the consistency of living things. These would be safer for people to interact with. They could also perform a variety of functions—such as squeezing through narrow openings in search and rescue operations—that conventional hard robots can’t.
Soft stretchiness and the ability to conduct electricity have been hard to combine in the same material. In 2024, a team of engineers from England working in the field of soft robotics reported a breakthrough: an electric battery with the consistency of stiff jelly.
The researchers were inspired by the electric organ of an electric eel, which can generate enough electricity to stun the eel’s prey with a powerful shock.
They used a material called a hydrogel, which consists of a three dimensional network of polymer molecules combined with water. They added other substances to make the hydrogel function as a battery. Like the electric organ, the battery uses electrically charged atoms, called ions, to conduct electricity. The battery can be stretched to as much as ten times its original length without losing its ability to conduct electricity, and it can recover its original shape after being stretched or squashed. The researchers hope next to test the new battery inside living animals to determine whether it is suitable for medical applications.
Read More:
- Highly stretchable dynamic hydrogels for soft multilayer electronics, Science Advances
- Completely stretchy lithium-ion battery for flexible electronics
- Self-healing ‘jelly batteries’ work in human brains
- Cambridge’s self-healing jelly batteries can transform soft robotics
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Reviewed by Daniel Mandler, Professor of Chemistry, Hebrew University in Jerusalem.
