超级电容器低温有机电解液研究

Investigation of low temperature organic electrolytes for supercapacitors

在四氟硼酸螺环季铵盐(SBP-BF4)/乙腈(AN)电解液体系中,分别加入四氢呋喃(THF)和2-甲基四氢呋喃(Me THF)后,采用100 F商品化碳基超级电容器研究电解液的低温性能。在0.5 A/g的电流密度下进行恒流充放电测试,结果表明两种电解液在-70℃的低温环境下仍具有良好的储能性能。其中加入THF的电解液低温性能最佳,-70℃时容量衰减至25℃时的85%,内阻增大至220%。

Tetrahydrofuran（THF）and 2-methyltetrahydrofuran （MeTHF） were added into a supercapacitor electrolyte, spiro-（1,1＇）-bipyrrolidinium tetrafluoroborate（SBP-BF4） /acetonitrile（AN） system, as low temperature solvents. The low temperature performance of these two electrolytes was investigated by applied in 100 F commemial electrochemical double layer capacitors （EDLC） samples. The results of low temperature （-70 ℃ ） charging-discharging tests show that the electrochemical performance of these two electrolytes is acceptable at -70 ℃ with a current density of 0.5 Ng. Especially the electrolyte of 1 mol/L SBP-BF4 in AN＋THF, the sample obtains excellent low temperature performance with 85% capacity remained and 220% internal resistance at -70 ℃ compared to the values at 25℃.