Thermal degradation analyses of carbonate solvents used in Li-ion batteries

Electrolyte-Additive-Driven Interfacial Engineering for High-Capacity Electrodes in Lithium-Ion Batteries: Promise and Challenges

“…The thermal decomposition of DMC and EMC produces CO 2 , CH 4 , CH 3 OH, H 2 , CO, CH 3 OCH 3 , and C 2 H 4 at high temperatures. In the case of EMC, C 2 H 6 and C 2 H 5 OH are also generated . In addition, EC contributes to gas generation by reacting with a small amount of H 2 O while producing CO 2 and ethylene glycol (EC + H 2 O → C 2 H 4 (OH) 2 + CO 2 ↑) .…”

Investigation of Water‐Soluble Binders for LiNi0.5Mn1.5O4‐Based Full Cells

“…Small differences in chemical shift with other reported values might be due to different ratios of carbonate to ether units, different chain lengths and/or variation in terminal groups [25] . Furthermore, the triplet around 1 ppm together with the doublet at 3.4 ppm could be assigned to the degradation of diethyl carbonate forming ethanol or diethyl ether, also releasing CO 2 [28–30] . The electrolytes from all three cells contain HF, confirmed by the appearance of the peaks at −167.7 and −190 ppm corresponding to HF in various coordination environments and complexations, [31] and a peak at −148 ppm in the 19 F NMR spectra (Figures S5 c and d), corresponding to BF 4 − as a result of the reaction between HF and the glass from NMR tube [32,33] .…”

“…[25] Furthermore, the triplet around 1 ppm together with the doublet at 3.4 ppm could be assigned to the degradation of diethyl carbonate forming ethanol or diethyl ether, also releasing CO 2 . [28][29][30] The electrolytes from all three cells contain HF, confirmed by the appearance of the peaks at À 167.7 and À 190 ppm corresponding to HF in various coordination environments and complexations, [31] and a peak at À 148 ppm in the 19 F NMR spectra (Figures S5 c and d), corresponding to BF 4…”

“… [25] Furthermore, the triplet around 1 ppm together with the doublet at 3.4 ppm could be assigned to the degradation of diethyl carbonate forming ethanol or diethyl ether, also releasing CO 2 . [ 28 , 29 , 30 ] The electrolytes from all three cells contain HF, confirmed by the appearance of the peaks at −167.7 and −190 ppm corresponding to HF in various coordination environments and complexations, [31] and a peak at −148 ppm in the 19 F NMR spectra (Figures S5 c and d), corresponding to BF 4 − as a result of the reaction between HF and the glass from NMR tube. [ 32 , 33 ] One notable difference between these spectra is that the electrolyte from the cells with LNMO_CMC and LNMO_PVdF‐HFP showed a doublet at −69.7 ppm which could confirm residues of fluorophosphates.…”

Experimental evaluation of thermolysis-driven gas emissions from LiPF6-carbonate electrolyte used in lithium-ion batteries

“…However, as lithium-ion batteries are becoming increasingly prevalent in many vital industries and consumer electronics, their thermal safety and fault prevention are becoming a top priority [2] . When a lithium-ion battery is subjected to overheating, overcharging, or overdischarging, a wide variety of gas can be released [3][4][5][6][7] . In addition, the emission of flammable and explosive gases is often instantaneous due to the thermal decomposition of electrolytes and other electrochemical side reactions during thermal runaway.…”