A research team from the Korea Institute of Science and Technology has developed a soft, mechanically deformable, and stretchable lithium battery.
The battery’s materials, including the anode, cathode, current collector, electrolytes, and encapsulant, are stretchable and printable, say the team.
The researchers reported the battery possesses the mechanical stability to maintain performance after more than 1,000 “pulls” of the battery, a stretchability of 50% or above, and long-term stability in air.
The battery is also able to incorporate existing lithium-ion battery materials, as it exhibited energy storage density (~2.8 mWh/cm2) of a level similar to that of commercially available lithium-ion batteries at a driving voltage of 3.3 V or higher.
The research results were published in the peer reviewed journal ACS Nano.
The research team was led by Dr. Jeong Gon Son from the Soft Hybrid Materials Research Center at the Korea Institute of Science and Technology (KIST).
To enhance stretchability, the research team avoided using previously studied materials, such as rubber, and used an organic gel material, developed and applied based on the existing binder material.
This material holds the active electrode materials in place and facilitates the transfer of ions.
In addition, a conductive ink was fabricated using a material with excellent stretchability and gas barrier properties to serve as a current collector material.
Moreover, the research team directly printed the electrode and current collector materials, which they had developed on either side of a of spandex arm guard, and applied a stretchable encapsulant to the material, demonstrating the ability to print a stretchable high-voltage organic battery directly on clothing.
Using the battery, the research team was able to continuously power a smart watch even when it was being put on, taken off, or stretched.