Integration of Flexible Energy Harvesters to Directly Power Thin Film Flexible Displays
In recent decades, research and development of flexible and wearable electronics have attracted significant interest and attention for applications in flexible displays, smart textiles, electronic skin, etc. To achieve these applications, much work has been focused on the development of flexible, portable energy sources that are capable of driving or charging such devices. In particular, energy harvesting has emerged as a sustainable method to collect energy from the environment, which can come from thermal, chemical, biological, solar, and mechanical sources. Since wearable electronics are worn on the human body, they can be strategically powered by the thermal and/or mechanical energy harvested from human motion. While much work has been done to improve the output of thermoelectric, piezoelectric, and triboelectric power sources, few studies have shown demonstrated direct coupling of flexible energy harvesters to directly power flexible devices. In most cases, either the input is externally applied or the output is externally measured; thereby, forgoing a fully integrated stand-alone device. Here, we have developed an integrated flexible self-powered display, which harvests the energy of human motion to actuate a display. The development of the power source is done in conjunction with reducing the power requirements of flexible displays. Our printable thin-film energy harvester generates output voltage up to 10s of V and output current up to µAs, enabling the actuation of displays with slight finger motions. This development will enable direct operation of stand-alone and roll-to-roll printable low power flexible electronics without external circuitry and holds potential for harvesting large-scale mechanical energy.