Contents lists available at ScienceDirect
Nano Energy
journal homepage: www.elsevier.com/locate/nanoen
Full paper
A low-frequency piezoelectric-electromagnetic-triboelectric hybrid
broadband vibration energy harvester
Xianming He
a,
⁎
, Quan Wen
a,b,
⁎⁎
, Yafeng Sun
a
, Zhiyu Wen
a
a
Microsystem Research Center, Key Laboratory of Fundamental Science of Micro/Nano, Device and System Technology, Key Laboratory for Optoelectronic Technology
and Systems Ministry of Education of China, Chongqing University, Chongqing 400044, China
b
Fraunhofer ENAS, Technologie-Campus 3, Chemnitz 09126, Germany
ARTICLE INFO
Keywords:
Hybrid
Broadband vibration energy harvester
Low-frequency
Picking-up vibration structure
Piezoelectric-electromagnetic-triboelectric
ABSTRACT
In practical applications, vibration-based energy harvesters are usually restricted by their output performance
and operating bandwidth. Therefore, improving the performance and increasing the operating bandwidth of
vibration energy harvester become to two significant and urgent research focuses in past years. In this paper, a
low-frequency piezoelectric-electromagnetic-triboelectric hybrid broadband vibration energy harvester is pre-
sented and investigated. It consists of flexible PET picking-up vibration structures which designed to achieve
broadband behavior at low acceleration. In the meanwhile, integrate piezoelectric, triboelectric and electro-
magnetic mechanisms successfully enhanced the electric output of the hybrid energy harvester. As a result, the
novel hybrid harvester can scavenge vibration energy at a wide vibration frequency. Under 0.5g acceleration at
20 Hz, the novel hybrid harvester obtained maximum output power 41.0 μW at a load resistance of 800.1 kΩ for
one PEH unit, 66.5 μW at a load resistance of 343.1 Ω for one EMEH unit, and 4.6 μW at a load resistance of
1.4 MΩ for one TEH unit, and the piezoelectric, electromagnetic and triboelectric EH units can reach 3.5 Hz,
10.0 Hz, and 18.1 Hz operating bandwidth under 0.5 g acceleration, respectively.
1. Introduction
In recent years, vibration-based energy harvesting technique has
been considered to be a promising technology and has attracted no-
ticeable research interests for its long-life and high energy density,
which are urgently desired as power supplies for wireless sensor net-
works in medical and health care, environmental monitoring, and
modern electronic products, and so on. The majority of the vibration
energy harvesters (VEHs) are designed based on one particular trans-
form mechanisms which include piezoelectric [1,2], electrostatic [3,4],
electromagnetic [5,6] and triboelectric [7,8]. Most of them are de-
signed to achieve the maximum performance only when the Eigen-
frequency of VEHs matches the frequency of ambient vibration. Un-
fortunately, ambient available vibration sources [9,10] (such as ma-
chine-vibrations, human-walking, robotic movements, wind, ocean
waves) are usual frequency-varying. In some special cases, the vibration
energy may even randomly distribute over a wide frequency range.
Therefore, increasing the operating bandwidth of VEHs is crucial for
practical application.
Thanks to the fast progress of microelectronic, power consumption
of most wireless sensor networks is range from tens microwatts to
several watts. This progress made using ambient vibration energy
harvester as a power source for power autonomous system become
feasible. In order to archive the full power autonomous in practical
application, improving the output power of vibration energy harvesters
become significant and urgent. One of most effective and attractive
strategy to enhance the energy transform efficiency is to employ hybrid
conversion mechanisms. For example, the combination of electro-
magnetic and piezoelectric mechanisms, piezoelectric and triboelectric
mechanisms, electromagnetic and triboelectric mechanisms and so on.
Over the past few years, the piezoelectric energy harvester (PEH) is
comprehensively explored for its long service life, high power density
and high reliability. The triboelectric energy harvester (TEH) is first
reported by Wang's group in 2012 [7] which has superior performance
for harvesting small scale mechanical energy such as body motion
[11,12], wind [13,14], water waves [15,16], vibrations [17,18], rota-
tion [19], and even acoustic energy [20] . However, both the PEH and
the TEH have high internal impedance, which is a major drawback in
low load impedance systems. Electromagnetic energy harvesters, on the
other hand, collected the energy and generated current from coils based
http://dx.doi.org/10.1016/j.nanoen.2017.08.024
Received 28 June 2017; Received in revised form 13 August 2017; Accepted 16 August 2017
⁎
Corresponding author.
⁎⁎
Corresponding author at: Microsystem Research Center, Key Laboratory of Fundamental Science of Micro/Nano, Device and System Technology, Key Laboratory for Optoelectronic
Technology and Systems Ministry of Education of China, Chongqing University, Chongqing 400044, China.
E-mail addresses: hexianming@cqu.edu.cn (X. He), hotspring1945@gmail.com (Q. Wen).
Nano Energy 40 (2017) 300–307
Available online 17 August 2017
2211-2855/ © 2017 Elsevier Ltd. All rights reserved.
MARK