V. Focused Fundamental Research - EERE - U.S. Department of ...

V.E.6 Investigation of Critical Parameters in Li-ion Battery Electrodes (LBNL)
Cabana – LBNL
% metalic Nickel
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Figure V - 206: (Top) -XAS map of NiO electrodes reduced halfway at C/20
and 1C rate. (Bottom) %Ni 0 resulting from the linear combination fit of XANE
spectra at different points on the map.
A method based on -XAS was developed to evaluate
charge distribution in composite electrodes with high
spatial resolution. Proof of concept was demonstrated with
NiO electrodes that were partially converted to Ni. Severe
inhomegeneities were found in all dimensions as the rate
of cycling was increased. More broadly, this work proves
that the three dimensions of these complex electrode
structures can be studied with this methodology. Because
XAS is sensitive to the very local changes of oxidation
state, its use could be extended to virtually any battery
electrode system, including those that undergo
amorphization during cycling.
A natural continuation of the work in FY2011 would
be to further study samples of LiNi 0.5 Mn 1.5 O 4 in which
crystal-chemistry effects are decoupled from particle size.
This goal can be achieved by following different annealing
procedures. A plan is in place to use synchrotron-based
tools to understand the reactivity of the surfaces of the
material toward the electrolyte and identify active species.
In parallel, the power of -XAS to study battery electrodes
will be extended to systems that are relevant to application,
such as high voltage cathodes or high capacity alloy-based
anodes.
4. J. Cabana, L. Monconduit, D. Larcher, and M. R.
Palacín. Adv. Mater. 2010, 22, E170-E192.
5. Analysis of the mechanism of conversion and the
microstructural changes upon cycling of high capacity
NiO electrodes. 2010 MRS Fall Meeting. Boston, MA,
Nov. 29th-Dec. 2nd, 2010.
6. Crystal and Microstructure Characterization of
LiNi 1/2 Mn 3/2 O 4 as a High Voltage Positive Electrode for
Li batteries. 2010 MRS Fall Meeting. Boston, MA,
Nov. 29th-Dec. 2nd, 2010.
7. Understanding how Li-ion Batteries Operate Using in
and ex situ Synchrotron-based Techniques. 2010
LCLS/SSRL Users’ Meeting. Menlo Park, CA, Oct.
17 th -21 st , 2010.
8. Understanding how Li-ion Batteries Operate Using in
and ex situ Synchrotron-based Techniques. 2010
LCLS/SSRL Users’ Meeting. Menlo Park, CA, Oct.
17 th -21 st , 2010.
9. Spectroscopic and imaging study of high capacity Li-ion
battery electrodes based on conversion reactions. 2010
ALS Users’ Meeting. Berkeley, CA, Oct. 13 th -15 th ,
2010.
10. Toward High Energy Density Li-ion Batteries.
Understanding the Key Parameters for Performing
Electrode Materials. 2010 TMF and NCEM Users’
Meeting. Berkeley, CA, Sept. 30 th -Oct. 1 st , 2010.
FY 2011 Publications/Presentations
1. 2011 DOE Annual Peer Review Meeting Presentation.
2. J. Cabana, J. Shirakawa, M. Nakayama, M. Wakihara
and C. P. Grey. J. Mater. Chem. 2011, 21, 10012­
10020.
3. J. Cabana, H. Zheng, A. K. Shukla, C. Kim, V. S.
Battaglia, M. Kunduraci. J. Electrochem. Soc. 2011,
158, A997–A1004.
Energy Storage R &D 650 FY 2011 Annual Progress Report