A photo‐thermoelectric twist to wireless energy transfer: radial flexible thermoelectric device powered by a high‐power laser beam

Abstract

Systems for wireless energy transmission (WET) are gaining prominence nowadays. This work presents a WET system based on the photo-thermoelectric effect. With an incident laser beam at λ = 1450 nm, a temperature gradient is generated in the radial flexible thermoelectric (TE) device, with a carbon-based light collector in its center to enhance the photoheating. The three-part prototype presents a unique approach by using a radial TE device with one simple manufacturing process - screen-printing. A TE ink with a polymeric matrix of poly(3,4-ethylenedioxythiophene) polystyrene sulfonate and doped-Poly(vinyl alcohol) with Sb-Bi-Te microparticles is developed (S∽33 µVK−1 and s∽10.31 Sm−1), presenting mechanical and electrical stability. Regarding the device, a full electrical analysis is performed, and the influence of the light collector is investigated using thermal tests, spectrophotometry, and numerical simulations. A maximum output voltage (Vout) of ∽16 mV and maximum power density of ∽25 µWm−2 are achieved with Plaser = 2 W. Moreover, the device's viability under extreme conditions is explored. At T∽180 K, a 25% increase in Vout compared to room-temperature conditions is achieved, and at low pressures (∽10‒6 Torr), an increase of 230% is obtained. Overall, this prototype allows the supply of energy at long distances and remote places, especially for space exploration.