Impact of the flame retardant additive triphenyl phosphate (TPP) on the performance of graphite/LiFePO4 cells in high power applications
Journal article, 2014
This study presents an extensive characterization of a standard Li-ion battery (LiB) electrolyte containing different concentrations of the flame retardant triphenyl phosphate (TPP) in the context of high power applications. Electrolyte characterization shows only a minor decrease in the electrolyte flammability for low TPP concentrations. The addition of TPP to the electrolyte leads to increased viscosity and decreased conductivity. The solvation of the lithium ion charge carriers seem to be directly affected by the TPP addition as evidenced by Raman spectroscopy and increased mass-transport resistivity. Graphite/LiFePO4 full cell tests show the energy efficiency to decrease with the addition of TPP. Specifically, diffusion resistivity is observed to be the main source of increased losses. Furthermore, TPP influences the interface chemistry on both the positive and the negative electrode. Higher concentrations of TPP lead to thicker interface layers on LiFePO4. Even though TPP is not electrochemically reduced on graphite, it does participate in SEI formation. TPP cannot be considered a suitable flame retardant for high power applications as there is only a minor impact of TPP on the flammability of the electrolyte for low concentrations of TPP, and a significant increase in polarization is observed for higher concentrations of TPP. (C) 2014 Elsevier B.V. All rights reserved.
BASIS-SETS
Flame retardant additive
ELECTROCHEMICAL PERFORMANCE
MIXED-SOLVENT
Electrolyte characterization
SOLVENT-CONTAINING ELECTROLYTES
FLUORINATED ALKYL PHOSPHATES
Triphenyl phosphate (TPP)
LEAN AD
JOURNAL OF CHEMICAL PHYSICS
Hybrid Pulse Power Characterization (HPPC)
V72
CARBONATE
1980
P5639
NONFLAMMABLE ELECTROLYTES
NEGATIVE ELECTRODE
Electrode/electrolyte interface
Graphite/LiFePO4 cell
RAY
LITHIUM-ION BATTERIES
ETHYLENE
PHOTOELECTRON-SPECTROSCOPY
Author
K. C. Hogstrom
Uppsala University
H. Lundgren
Royal Institute of Technology (KTH)
Susanne Wilken
Chalmers, Applied Physics, Condensed Matter Physics
T. G. Zavalis
Royal Institute of Technology (KTH)
Mårten Behm
Royal Institute of Technology (KTH)
K. Edstrom
Uppsala University
Per Jacobsson
Chalmers, Applied Physics, Condensed Matter Physics
Patrik Johansson
Chalmers, Applied Physics, Condensed Matter Physics
Göran Lindbergh
Royal Institute of Technology (KTH)
Journal of Power Sources
0378-7753 (ISSN)
Vol. 256 430-439Subject Categories
Inorganic Chemistry
Areas of Advance
Transport
Energy
Materials Science
DOI
10.1016/j.jpowsour.2014.01.022