Effect Of Carbon Electrode And Dielectric On Performance Of Supercapacitor And Its Equivalent Model Simulation

Supercapacitor is a new electronic device.It has high power density and low Equivalent Series Resistance,high charging and discharging efficiency,low maintenance requirements,environmental friendliness and so on.In high-power energy storage systems,supercapacitor as an energy storage element has received more and more attention in application fields.Its rapid power absorption and release capability makes it more suitable than energy storage systems composed of various batteries in areas requiring rapid power change.However,for a long time,the analysis of the model of supercapacitors has been on the theoretical level,and the equivalent model of the electrical performance of supercapacitors can be described without a simple measurement of the voltage and current of the capacitor port.A simple model is used to explain the redistribution of super capacitor in high-power cycle,which can optimize engineering design,simplify control algorithm and reduce the computation amount of upper and lower machine in engineering application.The types and particle sizes of electrode carbon materials for supercapacitors have been studied in the article.It is found that coconut shell carbon with 10?m has the best capacitor capacity decay rate and internal resistance growth rate.The thickness of the diaphragm has a great influence on the capacitor.The capacitor made of the diaphragm with a thickness of 20?m can control the Equivalent Series Resistance growth rate to60%during the aging termination period.Through the analysis of ET₄NBF₄ and SBP-BF₄ electrolyte dissolved in AN electrolyte at the concentration of 1 mol/L,the electrolyte energy with SBP-BF₄ as solute is obtained,so that the capacity attenuation at the end of life is controlled at 21.52%and the Equivalent Series Resistance growth rate is controlled at 36%,which is beneficial to the improvement of product consistency.Working voltage is a fatal factor causing capacitor attenuation.After 1344 hours of aging,the capacitance decay rate of working voltage 2.8V is-25.8%,and the Equivalent Series Resistance growth rate is 72.6%,while when the voltage reaches 3V,capacitance decay rate is-50.31%,and the Equivalent Series Resistance growth rate is645.33%.The aging test of supercapacitor monomer prepared from optimized materials and media shows that the optimized monomer has a capacitance decay rate of-15.71%and the Equivalent Series Resistance growth rate 43.83%at the end of its life,with good product consistency and stable performance..Based on the typical equivalent model of supercapacitor with three RC branches,the model is simplified to a two RC branch model according to the current application environment,and the two RC branch models are simulated using the off-line parameter identification function integrated by Simulink.The model is applied to the analysis and calculation of the newly manufactured improved and optimized supercapacitor monomer,and whether the calculation of the capacity and equivalent series resistance of the supercapacitor by the model is in line with the actual measurement results is verified,and the measurement results are analyzed to determine the reliability of the model.In the application process,it is necessary to identify the charge state?SOC?of the supercapacitor and the health of the Supercapacitor?SOH?.The SOC helps the user to monitor the amount of charge stored in the supercapacitor in real time,the SOH can help to monitor the health of supercapacitors,the linear least squares and EKF algorithm is used to identify the nonlinear capacitance,and the EKF is proposed to estimate the SOC of the two-branch model and identify the parameters simultaneously.At the same time,the SOH is calculated based on the equivalent series internal resistance or capacitance of supercapacitors.