Flexi-battery stretches 300%
An international research team has made a stretchable battery by forming an array of 2mm diameter Li-ion cells in a layer of silicone elastomer.
Individual cells are connected into a battery using 50µm copper tracks deposited in a serpentined serpentine pattern to allow flexibility without breakage.
Capacity is around 1.1mAh/cm2, and a stretchable coil has been incorporated to allow the battery to be charged wirelessly.
Poor cycle life and self-discharge remain issues.
Contributing institutions are: University of Illinois at Urbana-Champaign, Tsinghua University (Beijing) , Northwestern University (Illinois) and Hanyang University (Seoul).
The work is covered in Nature Communications.