Comparison of Organic Liquid Solution and Ionic Liquid as Electrolytes for Electric Double Layer Capacitors

  • 李 守慧

Student thesis: Master's Thesis


The capacitive behavior of liquid based electrolyte (MPPy TFSI 1M MPPy TFSI/PC 1 5M MPPy TFSI/PC and 1M Et4NBF4/PC) in different carbon materials (aMP aCF tMC) was analyzed using cyclic voltammogram galvanostatic charge discharge and electrochemical impedance spectroscopy The rate adjusted during the electrochemical measurement influence the capacitance behavior At high sweep rate or current rate the capacitive behavior is much influenced by the electrolyte properties such as viscosity and conductivity which is represented by EIS plot at high frequency region 1 5M MPPy TFSI/PC shows the most capacitive behavior at high rate The carbon materials were also analyzed using FTIR after cycling test using MPPy TFSI at 4V and 1M Et4NBF4/PC at 3V for 10000 cycles When using MPPy TFSI at 4V aMP has high retention The tMC carbon was only stable until 7000 cycle due to ion trapping which can be seen from the increasing % transmittance in FTIR curve The FTIR curve of aCF shows that the carbon reducted during cycling test thus aCF has less retention When applying 1M Et4NBF4/PC at 3V as the electrolyte aCF has the highest retention due to less ion trapping and no reduction on the carbon which can be seen from FTIR curve aMP has the worst retention due to worse ion trapping on the positive electrode
Date of Award2015 Feb 9
Original languageEnglish
SupervisorHsisheng Teng (Supervisor)

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