ISO/TR TECHNICAL 5602 REPORT First edition 2021-11 Sourcesoferrorintheuseof electrochemical impedance spectroscopy forthe investigation of coatings and other materials Sources d'erreur dans I'utilisation de la spectroscopied'impedance electrochimiquepour I'étudedesrevetements et autresmateriaux Reference number IS0/TR5602:2021(E) ISO @IS0 2021 IS0/TR5602:2021(E) COPYRIGHTPROTECTEDDOCUMENT IS02021 All rights reserved. Unless otherwise specified, or required in the context of its implementation, no part of this publication may be reproduced or utilized otherwisein anyform or by any means,electronic or mechanical, includingphotocopying,or postingon the internet or an intranet, without prior written permission. Permission can be requested from either Iso at the address below or Iso's member body in the country of the requester. ISo copyright office CP 401 : Ch.de Blandonnet 8 CH-1214 Vernier,Geneva Phone: +41 22 749 01 11 Email: [email protected] Website: www.iso.org Published in Switzerland ii IS0 2021-All rights reserved IS0/TR 5602:2021(E) Contents Page Foreword V Introduction. vi 1 Scope. .1 2 Normativereferences .1 3 Terms and definitions .1 4 Error in the make-up of the measuring cell 1 4.1 Roughness ofthe surface 1 4.2 O-ring - Considerations about the precise determination of the exposed area 3 4.3 Faulty cell make-up. .7 4.3.1Opticallydetectableleaks. 7 .7 4.3.2 Opticallynon-detectablecauses 4.4 Referenceelectrodes 9 General information on the distance between the reference and working 4.4.1 electrodes. 9 4.4.2 Shielding 11 4.4.3 Airbubbleinthereferenceelectrode 11 4.4.4 Poisoning of the reference electrode. 11 4.4.5 Bleeding of the reference electrode 11 4.5 Counterelectrodes 11 4.5.1 Relative sizes 11 4.5.2 Reactive counterelectrodes. 11 4.6 Gas inclusions in the measuring cell .11 5 Faults caused by electronics incl. shielding .12 5.1 Faraday cage 12 5.2 Extended cable (without active shielding) ..15 5.3 Cablebreaks 16 5.4 Contactresistancesbetweenmetallic contacts andtheworkingelectrode/counter electrode. 17 5.5 Inductivities 18 5.6 Measurement range switching 19 5.7 Scattering signals in power supply 20 5.8 Insufficient signal-to-noise ratio 22 5.9 Influence of peripheral devices 22 6 Parameter selection,measurement rangelimits .24 6.1 Open-leadtest 24 .24 6.2 Noteondummycells-IS016773-3 6.3 Unsuitable amplitude .. 24 6.4 Insufficientfrequencyrange 26 6.5 Repetitionrateforsubsequentmeasurements 27 .28 7 Non-stationary measurement conditions 7.1 General. 28 7.2 Temperature fluctuations. 29 7.3 Electrolytic conductivity 31 7.4 Swelling 31 7.5 Drifting OCP 31 7.6 Corroding working electrode 33 7.7 Reactive counterelectrodes. 33 7.8 Gasformationatthecounterelectrode .33 Design and selection of equivalent circuit diagrams. .34 8 8.1 Constantphase element. .34 8.2 Multiplepossibilitiesfortheselectionof equivalentcircuits .35 @IS0 2021 - All rights reserved ii