characterization of advanced electrode materials by means ... · •ion beam analysis techniques...

Characterization of advanced electrode materials by means of ion beam analysis technique for next generation Li-ion batteries

Spanish leaderProf. J. Manuel Perlado Martin

Japanish leaderProf. Yoshiaki Kato

Outline

•Motivation.

•Ion Beam Analysis Techniques for Li characterization.

•Experimental results on Li distribution characterization in Li-ion batteriespositive electrodes containing LixNi0.8Co0.15Al0.05O2 secondary particles(1.0≤x≤0.5).

•Experimental results on Li depth profiling in LiFeP.

•Conclusions.

Motivation

Motivation

Further development of Li-ion batteries requires Li characterization.

•Li-ion batteries consist of a positive and a negative electrode separated by anelectrolyte layer. When electrodes are linked by an external circuit, spontaneouselectrochemical reactions, which involve Li diffusion, take place.

•Therefore, the performance of a Li-ion battery (energy density, power, capacity,charge and discharge rates and lifetime) strongly depends, among other factors,on the characteristic of the electrodes and in particular on the Li diffusioncapabilities on them.

Available techniques for Li‐ion batteries characterization

Li characterization

Two remaining questions:

•Can we measure the Li concentration?

•If so, can we measure it during the charge-dischargeprocesses?

Li characterization

•TEM and EELS are techniques with surface sensitivity ”can not be applied to real electrodes”.•No quantitative information

The Electrochemical Society Interface • Fall 2011

Charge and discharge processes

Interest in the Li movement Can we measuring the batteries microstructure and composition during the charge-discharge processes?

YES, ….. BUTIn-situ XRD diffraction of C-LiFe0.6Mn0.4PO4 during the first charge-discharge cycle.

Detailed structure of the XRD pattern during the first charging process.

From XRD measurements only information about the crystalline phases can be obtained Is the Li always present in crystalline phases?

Ion Beam Analysis tecniques (IBA)

Courtesy of Dr. F. Munnik

Iman conmutador

Analysis-magnet

ScatteredIons

Electrons

X-rays

Nuclear reactionProducts

γ - rays

Recoil ionsTarget

Ion lens

RBS

NRA

PIGE

PIXE

ERDA

ionsource MeV-Ion-Accelerator

IBA for Li characterizationCharacterize the Li distribution by means of

•PIGE spatial characterization•NRA depth profiling

Advantages:

•Quantitative information about the elemental distribution.

•Simultaneous measurement of different elements.

•PIXE, PIGE and NRA spectra can be simultaneously measured.

•The use of micro-beams allow good spatial resolution.

•The use of external micro-beams allow measure large samples.

•The use of NRA allow measuring the Li depth profiling without destroyingsamples.

3/14/2013

IBA for Li characterization: necessity for cooperation

CMAM/UAMSPAIN

CNA/US

JAPANTIARA/JAEA

Li distribution characterization in positive electrodes containing LixNi0.8Co0.15Al0.05O2 secondary particles (1.0≤x≤0.5)

Objectives

•Characterize the elementaldistribution in Li-ion batterypositive electrodes containingLixNi0.8Co0.15Al0.05O2 (1.0≤x≤0.5)microparticles:

•As received (non-charged)•Charged

•Study the dependence of the Lidistribution on:

•Electrode thickness.•Charging conditions.

For these aims, cross-sectional samples need to be fabricated

As-received electrode

As-received individual microparticles

•Li-rich and Li-depletedregions μ-particlesdistribution.

•The Li distribution ishomogeneous within theindividual μ-particles.

K. Mima et al. NIMB 290 (2012) 79


We thank the team of TOYOTA for supplying and preparation of the samples as well as, for the very nice cooperation.

• One single measurementsgives information about theconstituents of• Active material: Ni, Co,

Al..• Binder: F, O, ..

• Li yield is higher for theuncharged than for thecharged electrode.

• The Ni yield is the same inboth electrode.

• Li/NiAR~1.10• Li/NiCh~0.94

K. Mima et al. NIMB 290 (2012) 79


The Li distribution is more homogeneous for the thin than for the thickelectrode.

Thickness dependence:

Th= 105 μm

Th= 35 μm

Th(μm)

dc(mA/cm2)

t (min)

35 2 15

105 6 15


K. Mima et al. NIMB 290 (2012) 79

• Li inhomogeneously distributes in both electrodes• Fast charge → Homogeneous gradient in the Li distribution• Slow charge→ Two regions with an abrupt boundary between them.

Charge rate dependence:

6m A/cm2

15 min.

0.6 mA/cm2

150 min.

K. Mima et al. NIMB 290 (2012) 79


•μ-PIGE and μ-PIXE techniques are successfully applied to accurately measurethe elemental (in particular Li) distribution in Li-ion batteries.

•Li inhomogenously distributes in the electrode to the random distribution ofthe secondary particles.

•The Li distribution within as-received individual secondary particles turns outto be homogeneous.

•The Li distribution in the cross sections of the electrodes is observed to dependon electrode thickness and on charge conditions.

•The Li distribution is:•Homogeneous in a thin electrode (35 μm),•Inhomogeneous when increasing the thickness (105 μm).

•For the thick electrode (105μm) slow charge rate gives rise to a small gradient ofthe Li distribution in the electrode regions close to the Al current collector.

CONCLUSIONS

CONCLUSIONS

Answer to questions:•Can we measure the Li concentration?

•Yes, we can.

•Can we measure it during the charge-dischargeprocesses?

•For the time being we have demonstrated that it can bemeasured in charged and uncharged batteries.

Manpower

Prof. José Manuel PerladoProf. Emilio Minguez

Dr. Jesús ÁlvarezAssoc. Prof. Emma del Río

Assoc. Prof. Raquel Gonzalez‐Arrabal

Assoc. Prof. Antonio RiveraMiguel Panizo

Prof. Yoshiaki Kato (GPI)Prof. Kunioki Mima (GPI)Prof. Sadao Nakai (GPI)

Assoc. Prof. Kazuhisa Fujita (GPI)Prof. Yoshiharu Uchimoto (Kyoto

University)Dr. Hirozumi Azuma (TCRL)

Dr. Yoshio Ukyo (TCRL)Prof. Hiroaki Nishimura (ILE)Prof. Tomihiro Kamiya (TIARA)

characterization of advanced electrode materials by means ... · •ion beam analysis techniques...

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