Office of Researchand DevelopmentNanoscale,X.ray,Computed,Tomography,of,Solid,Oxide,Fuel,Cell,Electrodes

William,K,EptingU1.3,Shawn,LitsterU3,Kirk,GerdesU1,Paul,A,Salvador1U2,,,

,,,,1National,Energy,Technology,LaboratoryU,UDSD,Department,of,Energy;,2Dept,of,Materials,Science,and,EngineeringU,Carnegie,Mellon,UnivD;,3Dept,of,Mechanical,EngineeringU,Carnegie,Mellon,UnivD

Acknowledgment:"s- part- of- the- National- ±nergy-Technology- µaboratory5s- research-portfolioC- this- work- was- conducted-under-the-R±S-contract-?±v%±222*222

UsingbabSphericalbDilatingbKernelbofbRb=bW:

Niµarge-pores

NivYSZC-pores

YSZC-no-pores

µSMvYSZC-pores

µSMµarge-pores

(2-μm

V2-μm

V2-μm

82-μm

~(22-μm

Hathodecurrentcollector

"ctive-cath.

"ctive-anode

±lectrolyte

"nodesupport

R-P-8

Hoarser-kernels

R-P-x

Spherical-kernel N8:-kernel Hubic-kernel

Startingvoxel

Dilate

YSZ

µSM

Void

YSZ1

µSM

Void

YSZ1

µSM1

Void1

YSZ1

µSM

Void1

Void

µSM

YSZ

Void

YSZ

YSZ-mbright3

Ielowresolution

limit

Iorderregion

Raw-virtual-x?-slice

IutC-thereal

structurelooks like

this•

Void-mdark3

Void µSM YSZ

Segmentation

greyscales-based-on-real-volumes-of-µSM-

elsewhere

RemovalbMethod:bMorphologicalbDilationThreexPhasebArtifact

Artifactbremovalbbybsequentialbdilationb

µSM-artifact-coating-all-YSZ-mthere-should-be-YSZvpore-interfaces3

µSM-artifact-even-coating-electrolyte-layer-mnot-physical3

Dilation:bDifferentbkernelsbandbsizes

StudyingbDilationbParametersbforbArtifactbRemovalReasonable-outcomes Unreasonable-outcomesUntreated

Isbit

phys

ical

?Ef

fect

bon

phas

ebfr

ac?

Effe

ctbo

npo

rebc

onta

ct?

Effe

ctbo

nph

aseb

perc

olat

ion?

Kernel: cubeRadius: 3

• AllRfeaturesRlookRvery“cube<ified”

• LSMRreducedRtoRsingleisolatedRcubes

VirtualR/DRslice

ThinnestRLSMRskinsgone

RemainingRLSMRthickenoughRtoRbeRreal

Qualitatively, shapesfaithful to orig. data

LSMRcovering all

YSZ < notRphysical

VoidYSZLSM

VirtualR/DRslice

LongRlimbspresent%Rsmallerthan nano<CT’sresolutionRlimit

Kernel: faces onlyRadius: 2

LSM

YSZ VoidElectrolyte

region

Z coord.-[μm]

Pha

se-f

ract

ion

LSMRFractionR>RPw,Not likely true.

LSMRlikelyRgettingboostRinRvolumeRfrom

artifact

LSM

YSZ VoidElectrolyte

region

Pha

se-f

ract

ion

LSMR<3z,RseemsunreasonablyRlow

Cube%RradiusRx

LSM

YSZ VoidElectrolyte

region

Sphere%RradiusR/

Z coord.-[μm]

zw,RLSMRseemsRhigh%RbutRpossiblemHommercial-composition-unknown3

LSMYSZ

VoidElectrolyte

region

Sphere%RradiusRx

Z coord.-[μm]

xw5xw5xw,RmixRalsoRseemsreasonable

LSM

YSZElectrolyte

region

Por

e-ex

posu

re

LSM<poreRexposurehasRtakenRaRlargeRhit

Cube%RradiusRx

LSMYSZ

Electrolyte

region

Sphere%RradiusR/

Z coord.-[μm]

YSZ<poreRexposureRhasRcomeRfromR~wtoRaRmeasurableRamount%RLSM<pore

exposureRstillRsizeableLSM

YSZ

Electrolyte

region

Sphere%RradiusRx

Z coord.-[μm]

YSZ<poreRandRLSM<poreRveryevenRnow%RthoughRTPBRmaybeRaboutRtheRsameRasRabove

LSM

YSZ

Electrolyte

region

Z coord.-[μm]

Por

e-ex

posu

re

YSZRhasRvirtuallyRwRcontactRwithRpores1

Unprocessed Sphere%RR=/ Sphere%RR=x Cube% R=x

Kernel:HsphereRadius:H2

YSZ-connectivity-pretty-reasonable-to-begin-with.

Void-connectivity-lowC-but-some-dead-pores-expected.

Void-connectivity--higher-v-closer-to-expected-characteristics.

"ll-three-phases-have-excellent-connectivity.

µSM-connectivity-has-been-severely-diminished-by-overvdilation.

Radiograph

±lectrolyte

V2-μm

V?-reconstruction

Virtual-x?-slices

Raw Segmented

NanoscalebXxraybCTbofSolidbOxidebFuelbCells

Hathode-materials•µSM

YSZ

µanthanum-strontiummanganateC-electronconductor-=-catalyst

YttriavstabilizedzirconiaC-oxide-conductor

%OV

X-rayHCTHwithH65HnmHresolution

LDbSpatialbAnalysisbofbTPBbDistribution

Shaftvlike-0dead-zone0

HeterogeneitybAnalysis

OngoingbWork:bAdvancedbSamplebPrepbforbLargerObMorebRepresentativebSamples

m*-μm3V

TPIs-determined-vertexvbyvvertex-in-V?

Vetices-connected-to-orthogonal-neighbors

Paths-smoothed-for-accurate-length-measurement

µocal-TPI-length-stored-on-voxelvbyvvoxel-basis-for-V?-spatial-analysis

82x82x(-μm-region-selected-for-heterogeneity-analysis-mbelow3

TPB density "cloud" visualization

Multiple-cubic-ROqs-placed-within-larger-volume

+ow-much-does-TIP-density-differ-between-each-cubeC-as-the-cubes-become-smallerz

Typ-.-%qIvS±M-size

±*2Zdeviation- from- mean-TPIC- based- on- U(Z-confidence- interval-on-Tvdistribution

µarger- volumes- mV2~- μm3- required- to-accurately-characterize-more-heterogeneous-industrial-cells-v-nanovHT-is-capable

N-P

-V)

N-P

-8*

N-P

-*

qdeal-sample0%racture- and- hope0- method-may- favor- statistically- unusual-samples•- 0why- did- it- break-therez0

qn- factC- this- sample- is- more-homogeneous-than-many-other-samples- previously- attempted-in- %qIvS±MC- which- exhibited-large- superporesC- or- *~- μm-boulders-of-solid-material.

Cut-and-polishHmethod

?irection-of-polishing

Hut Polish

Micrometervcontrolled-

fixture

Trim-with-laser ±xtract-pillar

Mount-vertically-for-nanovHT

AbstractUnderstanding- performance- degradation- in-SO%Hs- requires- an- understanding- of-electrode-microsctructurePrior-methods-yield-small-fields-of-view-below-scale-of-eterogeneity-present-in-some-cellsNanoscale- Xvray- HT- can- yield- V?- - -microstructure-of-a-larger-volume

Here,HweHpresentHimaging,HartifactHremoval,HandHanalysisHofHtheHscaleHofHheterogeneityHinHHindustrialHSOFCHelectrodes

Virtual-x?-slice-from-V?-image

82-μm

µSM

YSZPore ±

lect

roly

te

2.x 2.* 2.) 2.:2

(

82

8(

x2

x(

YSZµSM Pore

Z-c

oord

-[µm

]

Vol-fraction

Phase-fraction-analysis

Hur

rent

-col

lect

or

Phase-connectivity-analysis

AnalysisHofHlargerHcathodeHvolumeH445HxH32HxH25Hμmx

µSM YSZ Void2

2.x

2.*

2.)

2.:

8

µarg

est-c

ontig

uous

-frac

.

z