University of Cambridge Develops Stretchable 'Jelly Batteries' for Wearable Technology and Medical Applications

A Revolution in Battery Technology: The Creation of Stretchable 'Jelly Batteries'

A team of researchers from the University of Cambridge has pioneered the innovation of soft, stretchable 'jelly batteries', which may hold significant potential for applications such as powering wearable devices, soft robotics, and medical procedures, including drug delivery and epilepsy treatment. Drawing inspiration from electric eels, the scientists have developed a jelly-like material with a layered structure, capable of delivering electrical current.

The jelly batteries are not only stretchable but also demonstrate an ability to maintain conductivity even when stretched ten times their original length. It is the first instance of producing such a material combining these two properties, and the research findings have been published in the reputed journal, Science Advances.

The Science Behind Jelly Batteries

The key component behind these jelly batteries is hydrogels, essentially 3D polymer networks that consist predominantly of water - over 60%. These hydrogels have the unique property of reversible interactions, which allow for the regulation of the material's mechanical properties.

Hydrogels exhibit properties mimicking human tissues and can have their mechanical properties fine-tuned, making them ideal candidates for soft robotics and bioelectronics applications. However, a crucial factor for these applications is a combination of high stretchability and conductivity, which is usually challenging as these two properties tend to conflict.

In typical scenarios, materials tend to lose conductivity when stretched. The researchers achieved conductivity by charging neutral polymers that makeup hydrogels. They then modified the salt component of each gel to make them sticky, thereby allowing the creation of multiple layers accumulating higher energy potential. Unlike traditional electronics that use rigid metal materials and electrons as charge carriers, these jelly batteries use ions as charge carriers, similar to their inspiration, electric eels.

Potential Applications and Future Research

The unique properties of these jelly batteries make them suitable for medical implants. They exhibit pliability and mimic human tissues, making them more compatible with bodily functions and less likely to be rejected by the body or cause scar tissue. The hydrogels can withstand pressure without losing their shape and can self-heal when damaged, further adding to their versatility.

The research team's future plans include experimental evaluations in living organisms, and assessing the hydrogels' potential for various medical applications. This ground-breaking research was supported by the European Research Council and the Engineering and Physical Sciences Research Council (EPSRC). One of the head researchers, Oren Scherman serves as a Fellow of Jesus College, Cambridge.