Micro-scale energy harvesting systems and materials

Transcription

1 Micro-scale energy harvesting systems and materials Francesco Cottone NiPS laboratory, Department of Physics and Geology, Università di Perugia, Italy Micro Energy 2017 Gubbio 3 rd 7 th July 2017

2 Outline Microscale energy harvesters: potential applications and challenges A new concept of efficient MEMS-based electrostatic wideband vibration energy harvester Piezoelectric micro-pillars for energy harvesting Magnetic Shape Memory Alloy for energy harvesting Conclusions Micro Energy Cottone Francesco 2

3 Microscale energy harvesters and potential applications MEMS-based drug delivery systems Body-powered oximeter Leonov, V., & Vullers, R. J. (2009). Bohm S. et al Heart powered pacemaker Micro-robot for remote monitoring D. Tran, Stanford Univ Pacemaker consumption is 40uW. Beating heart could produce 200uW of power A. Freitas Jr., Nanomedicine, Landes Bioscience, 1999 The input power a 20 mg robotic fly is uw Micro Energy Cottone Francesco 3

4 Microscale energy harvesters and potential applications Jeon et al EM generator, Miao et al Chang. MIT 2013 ZnO nanowires Wang, Georgia Tech (2005) D. Briand, EPFL 2010 Mitcheson 2005 (UK) Electrostatic generator 20Hz 1g Cottone F., Basset P. ESIEE Paris Micro Energy Cottone Francesco 4

5 Microscale energy harvesters: scaling issues First order power calculus with William and Yates model V out h n 2C n E h l 2 k Ewh 3 l 3 w l m m 0.32m lwh 0.32( l / 4) 3 eff beam tip si si lwh 0.32( / 4) ( / 4) 3 si l mo lwh si l mo 2 m e A Pel A A 2 4 n ( m e ) 8n m E h 16Cn 2 m si l At max power condition e = m 2 2 By assuming A 1g m 0.01 h l / 200 w l /4 P el si / C 200 n E si m mo A l 2 4 Micro Energy Cottone Francesco 5

6 Microscale energy harvesters: scaling issues First order power calculus with William and Yates model Power A 2 l 4 where A is the acceleration and l the linear dimension MEMS-VEHs NEMS-VEHs NEMS-VEHs MEMS-VEHs Micro Energy Cottone Francesco 6

7 Microscale energy harvesters: scaling issues First order power calculus with William and Yates model V out h n 2C n E h l 2 Boudary conditions C1 doubly clamped 1,03 cantilever 0,162 l w k Ewh 3 l 3 Boudary conditions Uniform load Point load doubly clamped cantilever 0,67 0,25 Low efficiency off resonance High resonant frequency at miniature scales Micro Energy Cottone Francesco 7

8 Low-frequency MEMS electrostatic VEH Prototype fabrication process Y. Lu, F. Cottone, S. Boisseau, F. Marty, D. Galayko, and P. Basset, Appl. Phys. Lett Micro Energy Cottone Francesco 8

9 Low-frequency MEMS electrostatic VEH x s x b vibrations y d s k st k s m s L c m b d x dx du( x ) d y m d d m x x 2 2 s s s s 2 s st s, if 2 s dt dt dxs dt d x dx d y m d m x x L r dt dt dt 2 2 b b b, if / 2 2 b b 2 s b c b max R L d st g 0 x max Comb capacitor d RL C V V V dt 0 V 0 electrodes C( x ) N l 2gh 0 s 0 r f f 2 2 g0 xs 1 1 k x C ( x ) V if x x 2 2 U( xs ) 1 1 k k x C ( x ) V if x x s s s 0 s max 2 2 s st s s 0 s max Micro Energy Cottone Francesco 9

10 Low-frequency MEMS electrostatic VEH Silicon DRIE etching process Prototype fabrication process bottom glass HF etching doped Si Al mask patterning top glass cover HF etching (double side) 2 nd Version with ELECTRETS: experimental set-up of the corona charging on the parylene electret layer resist Si DRIE Insert tungsten micro-ball top glass cover bottom glass Anodic bonding bottom glass Acrylic glue bonding of top glass Fabricated at ESIEE Paris, Université de Paris-Est Micro Energy Cottone Francesco 10

11 MEMS e-veh at work Experimental test Working principle t n-1 Micro ball t i Impact time Micro ball t n Micro ball Silicon mass Silicon mass Silicon mass v sf ( e 1) m v ( m em ) v m m b bi b b si b s Velocity Amplified Energy Harvester At Stoke Institute, University of Limerick, Ireland Micro Energy Cottone Francesco 11

12 Capacitance (F) NiPS Laboratory Department of Physics and Geology University of Perugia First experimental results Experimental: Sine sweeping g / R L = 5 MOhm Cmax/Cmin = 3 Time (s) Power gain up to 525% F. Cottone et al., 2014 IEEE 27th Int. Conf. MEMS, Micro Energy Cottone Francesco 12

13 Numerical simulations Numerical: sine sweeping g / R L = 5 MOhm Generated power by the impacting ball in the range of 1-40 Hz Generated power by the resonant silicon mass around 150 Hz No power is generated in the range of 1-40 Hz without the impacting microball Generated power by the resonant silicon mass around 150 Hz Micro Energy Cottone Francesco 13

14 Numerical simulations Numerical: walking man / acc = 0.4 grms / Average Power: 1.34 µw Cavity upper and lower walls Micro-ball Micro Energy Cottone Francesco 14

15 Numerical and experimental results Numerical: running man / acc = 1.33 grms Short cavity = Lc = 1.5 mm Average Power: 1.34 µw Long cavity = Lc = 8.5 mm Average Power: 15 µw For large cavity Lc = 8.5 mm, the travelling range of the micro-ball is very large, impacts are less frequent but the it produces voltage spikes up to 50 V Micro Energy Cottone Francesco 15

16 Power (µw) NiPS Laboratory Department of Physics and Geology University of Perugia Device optimization Power Vs normalized cavity length Lc/2r 100,00 Running RMS acc: 1.33 grms Walking RMS acc: 0.4 grms 10,00 CAVITY LENGTH Lc: mm 1,00 1,00 3,00 5,00 7,00 9,00 11,00 Walking Running Max Power: 15µW Max Power density: 143µW/cm 3 Bias voltage: 20 V 0,10 0,01 Lc/d L c d The plot shows the generated power for different cavity length ratio L c /d over ball diameter at same walking and running acceleration It has been found that the power increases for larger L c when running. Micro Energy Cottone Francesco 16

17 Experimental results of e-veh with electrets without micro-ball with micro-ball Y. Lu, F. Cottone, S. Boisseau, F. Marty, D. Galayko, and P. Basset, Appl. Phys. Lett Micro Energy Cottone Francesco 17

18 Experimental results of e-veh with electrets TEST with hand shaking of the transient output voltage and extracted energy. (a) Vbias=21 V, a=2.0 grms, f=6.5 Hz; (b) Vbias=46 V, a=2.0 grms, f=4.7 Hz A 47-µF capacitor has been also charged through a bridge diode rectifier to 3.5 V to supply a wireless temperature sensor node. Y. Lu, F. Cottone, S. Boisseau, F. Marty, D. Galayko, and P. Basset, Appl. Phys. Lett Micro Energy Cottone Francesco 18

19 Performance comparison Vibration type MEMS Direction Accel. (grms) Main input Freq. (Hz) Vbias (V) Power (uw) Power Density (uw/cm3) Man walking X Man walking Y Man walking Z Man running Z Almost 1 order of magnitude higher than average power density of previous works P. D. Mitcheson, et al, Proceedings of the IEEE, vol. 96, pp , Micro Energy Cottone Francesco 19

20 Piezoelectric micro-pillars Microfibre-Nanowire: Piezoelectric ribbon: Wang(2008) Yang(2009) Micro Energy Cottone Francesco 20

21 Piezoelectric micro-pillars ZnO Pillar ZnO forest Why ZnO Non-toxic bio-compatible Wurzite structure Easy to fabricate Vast morfology Micro Energy Cottone Francesco 21

22 Piezoelectric micro-pillars Hydrotermal synthesis Length: 15 m Thickness: 4 6 um A. Di Michele, G. Clementi, M. Mattarelli and F. Cottone - Unpublished Micro Energy Cottone Francesco 22

23 Piezoelectric micro-pillars Stress-strain equations G. Clementi - M. Thesis t E S s T d E D d T E T Strain-charge form Length: 17 m Thickness: 5um First mode: 10.9 Mhz Micro Energy Cottone Francesco 23

24 MSMA energy harvesting RMS voltage [mv] RMS voltage RMS voltage Frequency [Hz] NiMnGa With MSMA Without MSMA FEM analysis Power [W] Bias field [T] H bias = 0.19 T H bias = 0.40 T H bias = 0.10 T H bias = 0.54 T Frequency [Hz] Resistance [k] M.A.A. Farsangi, F. Cottone, H. Sayyaadi, M.R. Zakerzadeh, F. Orfei, and L. Gammaitoni, Appl. Phys. Lett. 110, (2017). Micro Energy Cottone Francesco 24

25 Conclusions o A new concept of nonlinear MEMS electrostatic VEH as been proosed for lowfrequency and wideband energy harvesting with high efficiency below 60 Hz down to 10 Hz. o A numerical model has been developed in order to simulate the system behavior. The effect of the micro-ball impact is in agreement with the experimental results. o The MEMS e-veh shows very high power density tests indicate up to 142 W/cm 3 that open the possibility for self-powered biomedical devices such as pacemaker recharging with human motion. o Piezoelectric micro-pillars are under investigation for energy harvesting and sensing application. Base IDE electrodes setup will enable higher performance. o MSMA-based structural energy harvesting has been proven to work. Additional work is required. Micro Energy Cottone Francesco 25

26 Acknowledgments G. Clementi A. Di Michele M. Mattarelli L. Gammaitoni The authors acknowledge the support of P. Basset F. Marty D. Galayko T. Bourouina EU Horizon 2020 Programme (Grant n , PROTEUS) FP7 Marie Curie I (IEF) (Grant n , NEHSTech) FP7 (Grant n , ICT-Energy). Fondazione Cassa di Risparmio di Perugia (Bando a tema Ricerca di Base 2016, Project Code: Micro Energy Cottone Francesco 26