The broader impact/commercial potential of this project is to manufacture an advanced hybrid energy harvester that can enable broad deployment of wireless sensor networks. Self-sustainable uninterrupted low-cost power supply with small size is in urgent need for internet of things, portable electric devices, wireless sensor networks, infrastructure health monitoring, active control, and battleground soldier support. Scavenging ambient energy from environment to power these devices can eliminate the cost of replacing batteries, particularly in remote environment. The hybrid energy harvesters developed in this project will significantly improve the power output and response dynamic frequency, therefore provide sufficient power to many such devices. The high power density will also enable more frequent data acquisition and transmission of such sensor networks, and promote more ubiquitous deployment of advanced sensor networks. The automatic manufacturing process will enable their adoption by various customers including internet of things.
This Small Business Technology Transfer Research (STTR) Phase 2 project will develop manufacturing processes for advanced hybrid energy harvesters. Although piezoelectric energy harvesters have found broad applications, their power density and mechanical-electrical conversion efficiency are still low, with values at microwatts to milliwatt and <10%, respectively since they primarily operate at the d31 mode of the piezoelectric transducer and the mechanical impedance mismatch between the vibration source and the harvesting device. The Phase I project successfully demonstrated that the advanced hybrid energy harvesting device can provide significantly higher power density at > 100 mW and conversion efficiency at > 40% by using the more efficient d33 piezoelectric mode and with reduced stiffness in a curved structure that can efficiently transfer the energy from the vibration source to the active piezoelectric materials. The Phase II project will be focused on developing low-cost innovative automatic manufacturing process to enable their practical applications in commercial and industrial market.
