Upload
others
View
2
Download
0
Embed Size (px)
Citation preview
Accelerating Electrolyte Design ProcessVijay Murugesan, Zimin Nie, Xiaoliang Wei, Aaron Hollas, Wei Wang & Vince Sprenkle
Electrochemical Materials & Systems Group,
Pacific Northwest National Laboratory,
Richland, WA 99352
File
Na
me
//F
ile D
ate
//
P
NN
L-S
A-#
####
Objectives:
Ability to predict the solubility, stability, redox potential and
overall performance of redox flow battery electrolytes
Develop screening procedure using combined computational and
experimental methods to evaluate and identify the optimal solvents,
additives and redox active molecules
Designing vanadium based electrolytes:
Summary and Perspective:
Ion solvation study reveals, thermally activated precipitation of V5+
electrolyte can be suppressed through inhibiting deprotonation
process and/or perturbing the formation of higher order oligomers.
Acknowledgements
This work is supported by the U.S. Department of Energy (DOE) Office of Electricity
Delivery and Energy Reliability under contract No. 57558. PNNL is a operated by
Battelle Memorial Institute for the DOE under contract DE-AC05-76RL01830
Contact: Vijay Murugesan
Electrochemical Materials & Systems Group
Energy & Environmental Directorate
Pacific Northwest National Laboratory
Email: [email protected]
Tel: (509)-371-6540
References:
1. Advanced Energy Materials 1 (3), 394-400, 2011.2. Journal of Power Sources 196 (7), 3669-3672, 2011.3. Advanced Materials 26 (45), 7649-7653, 2014.4. Nature communications 6, 6303, 2015.5. ChemPlusChem 80 (2), 428-437, 2015.
Designing organic-aqueous electrolytes:
Vanadium solvation structure and ligand exchange dynamics dictates
the functional properties of electrolyte.
Designing bi-additives that can enable precise tuning of ion solvation
and subsequently optimal battery performance.
51V NMRTuning V5+ solvation – Bi-additives
[V.6H2O]+2 [V.6H2O]+3 [VO.5H2O]+2[VO2.2H2O]+1
Designing mixed acid flow battery electrolyte through inhibiting
deprotonation reaction of V5+ solvation with chloride substitution. Density functional theory (DFT) based computational screening method
is adopted to design optimal functional groups by predicting the
solubility and redox potential of organic redox molecules.
Adopting asymmetric molecular structure and charge distribution within
redox molecule through addition of functional groups can significantly
enhance the solubility of organic redox molecules . A vigorous DFT
based screening procedure is developed for optimal electrolyte design.
[VO2.2H2O]+1[VO2.Cl. 3H2O]+1 [VO2.PO4. 3H2O]-2
1 2 3 4 5 6 7 80.0
-0.2
-0.4
-0.6
-0.8
-1.0
-1.2
-1.4
-1.6
C
A
Redox Potential
Parent and Derivatives
E°’
1/2
(V v
s S
HE
)
Solv
atio
n E
ner
gy
(eV
)
Parent and Derivatives
1 2 3 4 5 6 7 8 9
0
-2
-4
-6
-8
-10
B
A
Solvation Energy
31P NMR
Composition of additive system is critical, as it dictates the rotational and
translational ion dynamics and subsequently solubility and viscosity .
Phosphate rotation Preferential solvation of NH4+
Columbic Potential
V5+ Oligomerization