High flash point electrolyte for use in lithium-ion batteries

作者：Isken P; Dippel C; Schmitz R; Schmitz R W; Kunze M; Passerini S; Winter M; Lex Balducci A^*

来源：Electrochimica Acta, 2011, 56(22): 7530-7535.

DOI：10.1016/j.electacta.2011.06.095

• Lithium-ion battery
• High flash point electrolyte
• Safety
• Adiponitrile

The high flash point solvent adiponitrile (ADN) was investigated as co-solvent with ethylene carbonate (EC) for use as lithium-ion battery electrolyte. The flash point of this solvent mixture was more than 110 degrees C higher than that of conventional electrolyte solutions involving volatile linear carbonate components, such as diethyl carbonate (DEC) or dimethyl carbonate (DMC). The electrolyte based on EC:ADN (1:1 wt) with lithium tetrafluoroborate (LiBF(4)) displayed a conductivity of 2.6 mS cm(-1) and no aluminum corrosion. In addition, it showed higher anodic stability on a Pt electrode than the standard electrolyte 1 M lithium hexafluorophosphate (LiPF(6)) in EC:DEC (3:7 wt). Graphite/Li half cells using this electrolyte showed excellent rate capability up to 5C and good cycling stability (more than 98% capacity retention after 50 cycles at 1C). Additionally, the electrolyte was investigated in NCM/Li half cells. The cells were able to reach a capacity of 104 mAh g(-1) at 5C and capacity retention of more than 97% after 50 cycles. These results show that an electrolyte with a considerably increased flash point with respect to common electrolyte systems comprising linear carbonates, could be realized without any negative effects on the electrochemical performance in Li-half cells.

• 出版日期2011-9-1