Supercapacitive Strain Sensor With Ultrahigh Sensitivity and Range

This article develops a novel strain sensor with ultrahigh sensitivity and range that can be easily fabricated using a paper-based electrolyte and two metal pins bought from a local hardware store. No cleanroom facilities are needed. The sensor utilizes a new sensing principle consisting of a paper-based solid-state electrolyte, which deforms in response to strain and changes its contact area with a pair of electrodes. This results in a highly sensitive capacitance change in a double-layer supercapacitor. The new sensor is shown to have a monotonically increasing response for strains as large as 25%, while at the same time providing a high measurement resolution of 0.025% strain. The new sensor could enable a new generation of ubiquitous monitoring applications by replacing more expensive traditional strain sensors.