This new, flexible battery is based on the Japanese cutting and folding paper art of kirigami

Flexibility is poised as the next evolutionary leap in electronics, incorporating a new performance parameter atop the traditional factors of speed and power efficiency. But in order to construct a phone as bendable as a sheet of paper, we must first overcome the monumental task of redesigning every single component within — battery, screen, motherboard, RAM, etc, — to accommodate the needed flexibility. 

Using the underlying principles of the intricate Japanese paper cutting art known as “Kirigami,” researchers from Arizona State University and China’s Jinan University have created what may be heralded as the most flexible batteries inside a wearable electronics.

The end result? A lithium-ion battery that can stretch more than 150 percent of its original size, while continuing the power the device to which it’s attached.

 
The practice of kirigami entails delicately cutting and folding paper to create slits that interlock into an intricate three dimensional design. The very word “kirigami” is a compound of the Japanese words to cut “kiru,” and paper “kami.” 

Adhering to these principles, the ASU team led by mechanical and aerospace engineering associate professor Hanqing Jiang, created a slurry of graphite and lithium cobalt dioxide to store and release the electricity as needed, coated aluminum sheets with the substance, and intricately cut and folded creases into the aluminum foil to create stretchy serpentine shapes. Finally, the team replaced the 300mAh battery inside a Samsung’s Gear 2 smartwatch.

The new battery lithium-ion battery was then sewn on the Gear 2’s elastic band, and stretched to 150% of its original size to power the smart watch. Remarkably, Gear 2 worked, and continued to work even after a wearer bent and stretched his bicep, suggesting the device’s potential for powering flexible wearable devices.

“The kirigami-based methodology can be readily expanded to other applications to develop highly stretchable devices and thus deeply and broadly impact the field of stretchable and wearable electronics,” Jiang explains, “This type of battery could potentially be used to replace the bulky and rigid batteries that are limiting the development of compact wearable electronic devices.

The primary advantage of a kirigami-based approach is it’s significantly better suited for contemporary manufacturing technologies, as folding and cutting is more likely to create a surface that remains even after stretching than if the folding-only technique of origami were to be applied.

Source: Extremetech via Nature