With the new innovation of scientists, your favourite gadgets can take any shape! Nicholas Kotov and his colleagues of the University of Michigan have developed a conducting component for a lithium-ion battery that maintains its electrical conductivity even when stretched.
The new version of the conductor is made from multiple layers of polyurethane and gold nanoparticles. Polyurethane is a polymer used to make common objects such as foam sponges and garden hoses. Layers of negatively charged nanoparticles are alternated with positively charged layers of the softer polymer. As the conductor is stretched, the gold nanoparticles self-organise into aligned pathways, allowing them to continue conducting electricity.
So far, the major challenge of designing flexible batteries was finding a balance between stretchiness and electrical conductivity, says Kotov. The team tested the performance of the conductor in a battery with a lithium electrolyte. The stretchable battery has a lower power density than regular lithium-ion batteries, but after 1000 cycles, it retained 96 per cent of its capacity. This dropped significantly in tests in which the battery was always in its stretched state: under those conditions, it retained only 72 per cent of its capacity after just 10 cycles. But once the strain is released, its capacity increases again.
Kotov’s thinks such batteries could be used in wearable or implantable devices, as well as used in soft robots with flexible legs or tentacles. He says the properties of the battery can be modified. “We can adapt to the specific mechanics and charge storage requirements that implantable devices or other devices might need.”
The new invention could change the way gadgets look in the future. Though not sure how it would be, let’s wait until the product is commercialized and the innovators work towards incorporating the battery in their products.