Stretchy, self-healing lithium-ion batteries could be a viable power source for wearable mobile phones, soft robotics, and electronic skin, according to a new study.
The researchers have made small, stretching batteries that can power an LED light – but they say their work is shows “high promise” for building future stretchable and wearable electronics.
They’ve published their work in Supramolecular Materials.
While there are dozens of research prototypes for stretchable, flexible, and self-healing batteries, it’s not always as easy to combine the properties.
Lithium-ion batteries that are stretchable – that is, capable of lengthening or squeezing and then returning to its original shape – and self-healing have been particularly difficult to make.
“Our work provides a novel and viable strategy for the design of stretchable and self-healable energy storage devices, showing high promise for the application in stretchable and wearable electronics,” says senior author Professor Xiaokong Liu, a researcher at Jilin University, China.
Liu and colleagues made their battery out of long polymer molecules, connected to each other with nitrogen-carbon bonds called imine bonds.
These polymers could both bind the positive and negative electrodes of the battery together, and act as electrolytes, which allow charged particles to move between the electrodes.
The researchers used the polymers to build a tiny lithium-ion battery, using both lithium iron phosphate and lithium-titanate electrodes.
“Our achievement lies in the construction of a lithium-ion battery with all-in-one configuration, wherein the electrolyte and electrodes can be fused together at the interface through the exchange of the dynamic imine bonds existing in both the electrolyte and electrodes,” says Liu.
The battery could still provide power while being stretched, and after being cut in half and healed back together.
“This work provides a novel and viable strategy for the design of stretchable and self-healable energy storage devices,” write the researchers in their paper.