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Centre of Excellence POEMES, IEES (CLEPS), BULGARIAN ACADEMY OF SCIENCES
WP 2. Lead-acid batteries for POEMES, LABD
Scanning Electron Microscopy
(SEM) -
construction, components, features and
applications
Centre of Excellence POEMES, IEES (CLEPS), BULGARIAN ACADEMY OF SCIENCES
WP 2. Lead-acid batteries for POEMES, LABD
e-Electron gun
Vacuum tube
- Tungsten filament- Lanthanum hexaboride (LaB6) single crystal- field emission gun
Focussed e- beam
- accelerating voltage 20 – 200 keV
SEM construction, components and features
Spot size – nm to m range
Magnification: 100 – 200,000 xResolurion: 0,7 nm to 50 nm
Electron optics
Objective (final lens)JEOL JSM-890 field emission:
Magnification: 900,000 x35 keV, Resolurion: 0,7 nm
Microstructure of the specimen surface
Centre of Excellence POEMES, IEES (CLEPS), BULGARIAN ACADEMY OF SCIENCES
WP 2. Lead-acid batteries for POEMES, LABD
Sample (one / several)
e-
Condensing magnetic coils
SEM construction, components and features
Objective (final lens)
Electron optics
Au: sputter coater
Centre of Excellence POEMES, IEES (CLEPS), BULGARIAN ACADEMY OF SCIENCES
WP 2. Lead-acid batteries for POEMES, LABD
e-
Sample
Feature: images of morphology or topology - “3-d” view
Scan coils
Scan mode
SEM construction, components and features
Objective (final lens)
Condensing magnetic coils
Electron optics
Centre of Excellence POEMES, IEES (CLEPS), BULGARIAN ACADEMY OF SCIENCES
WP 2. Lead-acid batteries for POEMES, LABD
e-
Scan coils
Objective (final lens)
Secondary e-
0,1 - 1 eVTopography
Sample Amplifier & detector
SEM construction, components and features
Condensing magnetic coils
B/W photoCCD matrix
wwwvideo
PC control
Centre of Excellence POEMES, IEES (CLEPS), BULGARIAN ACADEMY OF SCIENCES
WP 2. Lead-acid batteries for POEMES, LABD
e-
Secondary X rays (element microanalysis, X-ray mapping)
Detector
Sample
SEM construction, components and features
Condensing magnetic coils
Objective (final lens)
Scan coils
WD(crystal)S: B – Am,EDS (Si,Ge,Li, Be): B–U(AM), spot 1 m, 0,1%
EPMA
Centre of Excellence POEMES, IEES (CLEPS), BULGARIAN ACADEMY OF SCIENCES
WP 2. Lead-acid batteries for POEMES, LABD
e-
EBS: crystallography,EBSD: local phase identification and orientation meas., EBS mapping: sp. lattice features, grain boundary misorientation
Scan coils
Back scattered e-
50-200 keVAtomic Nr, topogr. Sample Amplifier &
detector
SEM construction, components and features
Condensing magnetic coils
Objective (final lens)
Centre of Excellence POEMES, IEES (CLEPS), BULGARIAN ACADEMY OF SCIENCES
WP 2. Lead-acid batteries for POEMES, LABD
e-
Magnification: up to 50,000 x, resolution 10 nm.
Sample
E (environmental) SEM
Environment:T: -200 to +1000oC
Humidity, Atmosphere
Real time videoVHS recording
- Effect of wetting/drying on fibres. - Water reactions with cement to produce bulk properties, -Soil science, catalysis, -Polymers, ceramics, -- Microelectronics.
Centre of Excellence POEMES, IEES (CLEPS), BULGARIAN ACADEMY OF SCIENCES
WP 2. Lead-acid batteries for POEMES, LABD
PbO2 crystals morphology vs. electrolyte concentration
6 M, 1.34 s.g. 5 M, 1.28 s.g.Source: D. Pavlov, A. Kirchev, M. Stoycheva and B. Monahov, Influence of H2SO4 concentration on the mechanism of the processes and on the electrochemical activity of the Pb/PbO2PbSO4 electrode, accepted for publication in J.Power Sources, 2004
Centre of Excellence POEMES, IEES (CLEPS), BULGARIAN ACADEMY OF SCIENCES
WP 2. Lead-acid batteries for POEMES, LABD
2.8 M, 1.17 s.g. 1.56 M, 1.095 s.g.
PbO2 crystals morphology vs. electrolyte concentration
Source: D. Pavlov, A. Kirchev, M. Stoycheva and B. Monahov, Influence of H2SO4 concentration on the mechanism of the processes and on the electrochemical activity of the Pb/PbO2PbSO4 electrode, accepted for publication in J.Power Sources, 2004
Centre of Excellence POEMES, IEES (CLEPS), BULGARIAN ACADEMY OF SCIENCES
WP 2. Lead-acid batteries for POEMES, LABD
0.18 M, 1.010 s.g.
0.5 M, 1.030 s.g.
PbO2 crystals morphology vs. electrolyte concentration
Source: D. Pavlov, A. Kirchev, M. Stoycheva and B. Monahov, Influence of H2SO4 concentration on the mechanism of the processes and on the electrochemical activity of the Pb/PbO2PbSO4 electrode, accepted for publication in J.Power Sources, 2004
Centre of Excellence POEMES, IEES (CLEPS), BULGARIAN ACADEMY OF SCIENCES
WP 2. Lead-acid batteries for POEMES, LABD
Our secret goal: “green” battery, 100% natural products
Nephrolepis(fern)
Polypodium(fern)
Centre of Excellence POEMES, IEES (CLEPS), BULGARIAN ACADEMY OF SCIENCES
WP 2. Lead-acid batteries for POEMES, LABD
PAM, charged, after thermal rise
1 m
1 m
1 m
1 m
Source: D. Pavlov, B. Monahov, and A. Kirchev, to be published
Centre of Excellence POEMES, IEES (CLEPS), BULGARIAN ACADEMY OF SCIENCES
WP 2. Lead-acid batteries for POEMES, LABD
NAM, formed, before thermal rise
1 m3.3 m
Source: D. Pavlov, B. Monahov, and A. Kirchev, to be published
Centre of Excellence POEMES, IEES (CLEPS), BULGARIAN ACADEMY OF SCIENCES
WP 2. Lead-acid batteries for POEMES, LABD
NAM, charged, after thermal rise
1 m 1 m
Source: D. Pavlov, B. Monahov, and A. Kirchev, to be published
Centre of Excellence POEMES, IEES (CLEPS), BULGARIAN ACADEMY OF SCIENCES
WP 2. Lead-acid batteries for POEMES, LABD
Determinations in PAM/AMCL/CL1. XRD: - phase composition,
- average crystallite size;2. SEM: - crystal morphology,
- structure
SGT positive plate structure studies setupSample collecting points
Pb CL AMCL PAM
PAM
Pb strap gridinterface
- sample collecting point
Centre of Excellence POEMES, IEES (CLEPS), BULGARIAN ACADEMY OF SCIENCES
WP 2. Lead-acid batteries for POEMES, LABD
Morphology of PbO2 in the corrosion layer
dense aggregates on the metal surface fine, globular, hydrated PbO2 particles, almost no pores
Centre of Excellence POEMES, IEES (CLEPS), BULGARIAN ACADEMY OF SCIENCES
WP 2. Lead-acid batteries for POEMES, LABD
dense structure
porous structure
Morphology of PbO2 in the AMCL
Centre of Excellence POEMES, IEES (CLEPS), BULGARIAN ACADEMY OF SCIENCES
WP 2. Lead-acid batteries for POEMES, LABD
e-
TEM construction, components and features
The internal structure of the specimen (2-d imaging)
Electron gunUacc - up to 1000 keV
Sample: 0,2 m
Magnification: 350 - 600,000 xResolurion: down to 0,2 nm
JEOL JEM-4010 - atomsMagnification: 2,000,000x
40-100 keV, Resolurion: 0,15 nm
Mesh, goniometer specimen stages
Secondary X rays (element microanalysis)
TEM microprobe
TEM nanoprobe
STEMEDS
CCD camera Cryogenic facility
Centre of Excellence POEMES, IEES (CLEPS), BULGARIAN ACADEMY OF SCIENCES
WP 2. Lead-acid batteries for POEMES, LABD
Source: D. Pavlov, I. Balkanov, and P. Rachev, J. Electrochem. Soc., 134 (1987) 2390.
a: TEM micrograph of an active mass agglomerate after discharge;
b: electronogram of the crystals in the defined area with interpretation of its
interplanar spacings
TEM micrograph and electron diffractogram of a PbO2 particle
Centre of Excellence POEMES, IEES (CLEPS), BULGARIAN ACADEMY OF SCIENCES
WP 2. Lead-acid batteries for POEMES, LABD
1. Structure of the Pb/PbSO4 electrode system. Membrane model of PbSO4.
2. Structure of the Pb/PbO/PbSO4 electrode system. Semiconductor model of PbOn.
3. Structure of PAM. PbO2 agglomerates, aggregates and particles. Hydrated structures in PAM and in the corrosion layer. Gel-crystal model of PbO2. Influence of the electrolyte concentration on the crystal morphology of PbO2.
4. Structure of NAM. Skeleton and energetic structures.
5. Structure of the CL. CL/AMCL/PAM model.
6. Mapping of PAM and the corrosion layer.
Battery knowledge developed using SEM/TEM microscopy