High-performance Piezoelectric Energy Harvesters for Self-powered Smart Wearables

Abstract/Technology Overview

Wearable devices such as smartwatches and activity trackers are changing our lifestyle towards a more convenient and healthier way. Along with the widespread market adoption of wearable devices, problems of the power source - battery becomes increasingly distinct. Batteries have limited lifespans and require frequent recharging. End-of-life battery disposal also poses severe environmental problems. Energy harvesting technology, which enables to harness energy from human daily activities and convert the wasted energy to electricity, is an alternative to batteries. The present invention is a unique two-layer band design of energy harvesters for wearables based on the piezoelectric effect to generate electricity. With the power management circuit, the generator can efficiently output and store energy during walking, running, jogging, or hand tapping.

The technology provider is looking for partners in the consumer electronics and urban testing sector to co-develop this technology.

Technology Features, Specifications and Advantages

  • The invented generator brings few changes to the structure of watches and has no side effect on the functions of smart watches and user experience.
  • The brand-new architecture operates in two modes: i) capture the kinetic energy caused by the inertial effect from gravity and the arm motions during human daily activities; ii) capture the impact energy when a hand strikes the case deliberately.
  • The unique two-layer energy harvester shows the maximum output power of 15.41 mW when hand tapping and is capable of continuously powering a watch or a screen when walking or hand tapping.
  • It has the advantages of relative high-power, reliability, small scale, light weight and low cost.

Potential Applications

Wide range of applications that are able to harvest energy by tiny movement or motion is apporpriate. They include, but not limit to, Consumer Electronics, Wearable Devices, Medical devices, Smart Vehicles, Internet of Things, etc. 

At initial stage, smartwatch or Activity Tracker is one of the implementations for which the prototype has been designed. Further potental applications are seeking for collaborative development.

Customer Benefit

A piezoelectric type of energy harvesters for wearables with relative high-power, reliability, small scale, light weight and low cost.

Contact Person

Stephen Ip


City University of Hong Kong

Technology Category
  • Actuators
  • Embedded Systems
  • Sensors & Instrumentation
  • Performance Monitoring System & Sensor
  • Power Conversion & Condition System
  • Healthcare ICT
  • Internet of Things & Wearable Technology
Technology Readiness Level
  • TRL 2

wearable device, smartwatch, energy harvest, piezoelectric, internet of things

View on demand webinars by clicking here