Wearable devices are not only limited in size, but also because they need to be worn for a long time, comfort is also very important, so they must also be very light, so the battery must be as small as possible. Lithium ion batteries are small in size, light in weight and large in capacity, which can help system design engineers meet size constraints and provide long battery life to satisfy consumers. Its higher working voltage means that fewer cells are needed, which can further reduce the size of the system and improve the design flexibility.

 

Integrating electronic products and the energy generated or stored thereby into various devices is a rapidly developing research field, which puts forward new requirements for electronic materials, such as designing batteries that can be used in clothing or other fabrics.

 

Scientists at the Korean Academy of science and Technology (Kist) considered such applications when developing such lithium-ion batteries, and their components can be stretched by up to 50% without affecting safety or performance.

 

Instead of trying to add inherently stretchable materials such as rubber to battery components, the team is committed to creating an "accordion like" structure, which increases the stretchability of inherently non stretchable materials. Using graphene and carbon nanotubes, scientists can build honeycomb composite frames, and then compress them inward like an accordion to give them tensile properties.

 

 

Then, they combined the electrode with gel electrolyte and stretchable packaging materials to make a working lithium-ion battery. A paper published on ACS Nano described the design of a stretchable lithium-ion battery based on a reentrant micro honeycomb electrode and a cross-linked gel electrolyte. The design proved that its capacity was 5.05 MAH per square centimeter, and it could still maintain 95.7% performance after 100 charge and discharge cycles. According to Kist, when the material is stretched to 50%, the battery also shows "superior electrochemical performance" after 500 tensile release cycles.

 

The University pointed out that all materials in the battery are active in the battery, and the additional benefit is to increase the tensile property. Jeong gon son, who led the research at Kist, said he hoped that this stretchable design could "provide a new example for the further development of wearable and implantable electronic devices in terms of stretchable energy storage systems."

Article source: First lithium power grid