TY  - JOUR
AU  - Kubot, Maximilian
AU  - Frankenstein, Lars
AU  - Muschiol, Elisabeth
AU  - Klein, Sven
AU  - Esselen, Melanie
AU  - Winter, Martin
AU  - Nowak, Sascha
AU  - Kasnatscheew, Johannes
TI  - Lithium Difluorophosphate: Boon for High Voltage Li Ion Batteries and a Bane for high Thermal Stability/low Toxicity: Towards Synergistic Dual‐Additives to Circumvent this Dilemma
JO  - ChemSusChem
VL  - 16
IS  - 6
SN  - 1864-5631
CY  - Weinheim
PB  - Wiley-VCH
M1  - FZJ-2023-00744
SP  - e202202189
PY  - 2023
N1  - Zudem gefördert durch: BMWK "Go3”(03ETE002D)
AB  - The specific energy/energy density of state-of-the-art (SOTA) Li-ion batteries can be increased by raising the upper charge voltage. However, instability of SOTA cathodes (i. e., LiNiyCoxMnyO2; x+y+z=1; NCM) triggers electrode crosstalk through enhanced transition metal (TM) dissolution and contributes to severe capacity fade; in the worst case, to a sudden death (“roll-over failure”). Lithium difluorophosphate (LiDFP) as electrolyte additive is able to boost high voltage performance by scavenging dissolved TMs. However, LiDFP is chemically unstable and rapidly decomposes to toxic (oligo)organofluorophosphates (OFPs) at elevated temperatures; a process that can be precisely analyzed by means of high-performance liquid chromatography–high resolution mass spectroscopy. The toxicity of LiDFP can be proven by the well-known acetylcholinesterase inhibition test. Interestingly, although fluoroethylene carbonate (FEC) is inappropriate for high voltage applications as a single electrolyte additive due to rollover failure, it is able to suppress formation of toxic OFPs. Based on this, a synergistic LiDFP/FEC dual-additive approach is suggested in this work, showing characteristic benefits of both individual additives (good capacity retention at high voltage in the presence of LiDFP and decreased OFP formation/toxicity induced by FEC).
LB  - PUB:(DE-HGF)16
C6  - 36533855
UR  - <Go to ISI:>//WOS:000916026500001
DO  - DOI:10.1002/cssc.202202189
UR  - https://juser.fz-juelich.de/record/917541
ER  -