Flexible batteries kept stable with stretchy metallic films

Stretchable films filled with liquid metal can protect flexible electronic devices from exposure to air and water. The finding could offer a potential way to improve the lifetime of future forms of wearable technology.

Most stretchable materials are highly permeable to gases. This makes it challenging to fully protect flexible electronic devices from things like air and moisture, which can ruin their performance.

Now researchers in China and the US have developed stretchable seals based on liquid metals that block the transport of oxygen and water. The seals are formed of a eutectic gallium indium alloy, which is laminated between two layers of silicone-based polymer.

The team that developed the seals showed how they can be used to dramatically increase the lifetime of a flexible lithium–ion battery. The researchers also highlighted how the liquid metal seals could be used to protect the working fluid in a stretchable phase-change-based heat transfer mechanism used to manage the temperature of flexible electronics.