Journal of the Korean Electrochemical Society (전기화학회지)

The Korean Electrochemical Society (한국전기화학회)
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Hybridization of the Energy Generator and Storage Device for Self-Powered Electronics

자가구동형 전자소자 구현을 위한 에너지 발전/저장 소자 융합 기술 동향

  • Lee, Ju-Hyuck (Department of Energy Science and Engineering, Daegu Gyeongbuk Institute of Science and Technology (DGIST))
  • 이주혁 (대구경북과학기술원에너지공학전공)
  • Received : 2018.10.24
  • Accepted : 2018.11.05
  • Published : 2018.11.30
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Abstract

Currently, hybridization of energy generator and storage devices is considered to be one of the most important energy-related technologies due to the possibility of replacing batteries or extending the lifetime of a batteries in accordance with increasing battery demand. This review aims to describe current progress on the mechanical energy generator and hybridization of energy generator and energy storage devices for self-powered electronics. First, the research trends related to energy generation devices using piezoelectric and triboelectric effect that convert physical energy into electric energy is introduced. In addition, integration of energy generators and energy storage devices is introduced. In particular, self-charging energy cells provide an innovative approach to the direct conversion of mechanical energy into electrochemical energy to decrease energy conversion loss.

최근 늘어나는 배터리 수요를 대처하기 위하여 배터리를 대체하거나 배터리의 구동시간을 늘리기 위한 방법으로 제시되고 있는 에너지 발전소자와 에너지 저장소자의 융합연구는 에너지 관련 기술분야에서 가장 관심받고 있는 분야중 하나이다. 본 리뷰논문에서는 물리에너지 발전소자의 최근 연구동향과 함께 에너지 발전소자와 저장소자의 융합연구 동향을 소개하고자 한다. 먼저, 물리에너지를 전기에너지로 변환하는 압전 특성과 마찰대전 특성을 이용한 에너지 발전소자 관련 연구동향을 소개한다. 또한 압전/마찰대전 에너지 발전소자와 에너지 저장소자의 융합 연구동향을 소개한다. 특히 자가충전 에너지소자의 물리에너지를 전기화학적 에너지로 변환하는 새로운 접근방법을 소개하고자 한다.

Keywords

JHHHB@_2018_v21n4_68_f0001.png 이미지

Fig. 6 Schematic diagram of module circuit for driving applications using energy generator and storage device.

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Fig. 1 (a) Invention of piezoelectric nanogenerator using vertically grown ZnO nanorods array with AFM tip.5) (b) Stretchable piezoelectric nanogenerator using wavy structured PZT Nanoribon on PDMS substrate.23) (c) Piezoelectric nanogenerator using micropatterned piezoelectric polymer P(VDF-TrFE).28)

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Fig. 2 (a) Monolayer top view geometry of (a) boron nitride (h-BN) and trigonal prismatic molybdenum disulfide (2HMoS2) with piezoelectric polarization, and calculated piezoelectric coefficient of TMDC.37) (b) Probing the piezoelectric property of free-standing monolayer MoS2 using piezoresponse force microscopy technique.38) (c) Experimental demonstration of the piezoelectric property of monolayer MoS2 based piezoelectric device.6) (d) Investigation of piezoelectric property of turbostratic stacking structured bilayer WSe2 based piezoelectric device.39)

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Fig. 3. (a) Supramolecular packing directs piezoelectric response in glycine amino acid crystals (left), and Simple energy harvesting method using ¥ᾶ-glycine crystals (right).43) (b) Growth of vertical FF peptide microrod arrays with controlled polarization and statistics of piezoelectric polarization direction of vertically grown FF peptide microrod measured by PFM method.46) (c) Schematic diagram depicting the fabrication process to create large-scale peptide nanotube arrays through meniscus-driven self-assembly, and unidirectional polarization of FF piezoelectric nanotubes measured by PFM method.47)

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Fig. 4 (a) Schematic illustration of power generation mechanism of triboelectric nanogenerator. (b) The four fundamental modes of triboelectric nanogenerator (vertical contact mode, lateral sliding mode, single electrode mode, and free-standing mode).

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Fig. 5 (a) Development of the triboelectric nanogenerator using micropatterned PDMS layer.49) (b) Development of the triboelectric nanogenerator using nano-porous structured PDMS layer.50) (c) Development of the textile-based wearable triboelectric nanogenerator using nanostructured PDMS layer, and demonstration of the Self-powered commercial LCD, LEDs, and a remote control (keyless vehicle entry system).51)

JHHHB@_2018_v21n4_68_f0007.png 이미지

Fig. 7 (a) Device structure of self-charging power cell by hybridizing a piezoelectric PVDF layer and a Li-ion battery, and (b) the working mechanism of the self-charging power cell driven by compressive strain.57)

JHHHB@_2018_v21n4_68_f0008.png 이미지

Fig. 8 (a) Schematic illustration for the working mechanism of the self-charging of hybrid piezoelectric-supercapacitor. (b) Self-charging profile of the hybrid piezoelectric-supercapacitor under an applied compressive force, and comparison of the charging voltage of the hybrid piezoelectric-supercapacitor under various applied compressive forces.65)

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