Chinese, US scientists design stretchable seal for electronic devices

SHANGHAI, Feb. 3 (Xinhua) -- An international group led by Chinese scientists has developed a kind of stretchable seal to better protect next-generation flexible electronic devices.

The study published in the journal Science on Friday details the liquid metal-based, soft, hermetic and wireless-communicable seals for stretchable systems.

The advancement in human-machine interfaces and other soft electronic technologies has raised demand for protective packaging for stretchable devices. Furthermore, conventional stretchable materials are often highly permeable and less hermetically sealed.

The researchers from Shanghai Jiao Tong University and North Carolina State University used a liquid metal called eutectic gallium indium with both low gas permeability and fluidic properties. They then tested the seals in a stretchable battery and a soft heat transfer device that incorporates volatile fluids.

The capacity retention of the battery was about 72.5 percent after 500 cycles, and the sealed heat transfer system showed an increased thermal conductivity while strained and heated.

They also demonstrated that the hermetic seals can be designed to enable wireless communication with a signal transmission window.