The “e-skin” looks a bit like a super-thin sticker. In actuality, it’s far more complex. A single sheet of the transparent e-skin consists of a soft integrated circuit that runs on five volts of electricity (just a fraction of the team’s 30-volt starting point). The e-skin’s tri-layer structure is dielectric, meaning it transmits electricity without conduction, and it consists of three inner layers that allow the integrated circuit to use a lower voltage. Each layer contains organic nanostructures that can be individually engineered to pick up on different sensory inputs; while one might detect temperature, another helps the user experience pressure. 

https://www.extremetech.com/science/stretchy-e-skin-facilitates-sense-of-touch