Low-order mathematical modelling of electric double layer supercapacitors using spectral methods

This work investigates two physics-based models that simulate the non-linear partial differential algebraic equations describing an electric double layer supercapacitor. In one model the linear dependence between electrolyte concentration and conductivity is accounted for, while in the other model i...

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Autors principals: Drummond, R, Howey, D, Duncan, S
Format: Journal article
Publicat: Elsevier 2015
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author Drummond, R
Howey, D
Duncan, S
author_facet Drummond, R
Howey, D
Duncan, S
author_sort Drummond, R
collection OXFORD
description This work investigates two physics-based models that simulate the non-linear partial differential algebraic equations describing an electric double layer supercapacitor. In one model the linear dependence between electrolyte concentration and conductivity is accounted for, while in the other model it is not. A spectral element method is used to discretise the model equations and it is found that the error convergence rate with respect to the number of elements is faster compared to a finite difference method. The increased accuracy of the spectral element approach means that, for a similar level of solution accuracy, the model simulation computing time is approximately 50% of that of the finite difference method. This suggests that the spectral element model could be used for control and state estimation purposes. For a typical supercapacitor charging profile, the numerical solutions from both models closely match experimental voltage and current data. However, when the electrolyte is dilute or where there is a long charging time, a noticeable difference between the numerical solutions of the two models is observed. Electrical impedance spectroscopy simulations show that the capacitance of the two models rapidly decreases when the frequency of the perturbation current exceeds an upper threshold.
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spelling oxford-uuid:b111523c-dca6-4f05-a64f-cc3c1a5509632022-03-27T04:01:10ZLow-order mathematical modelling of electric double layer supercapacitors using spectral methodsJournal articlehttp://purl.org/coar/resource_type/c_dcae04bcuuid:b111523c-dca6-4f05-a64f-cc3c1a550963Symplectic Elements at OxfordElsevier2015Drummond, RHowey, DDuncan, SThis work investigates two physics-based models that simulate the non-linear partial differential algebraic equations describing an electric double layer supercapacitor. In one model the linear dependence between electrolyte concentration and conductivity is accounted for, while in the other model it is not. A spectral element method is used to discretise the model equations and it is found that the error convergence rate with respect to the number of elements is faster compared to a finite difference method. The increased accuracy of the spectral element approach means that, for a similar level of solution accuracy, the model simulation computing time is approximately 50% of that of the finite difference method. This suggests that the spectral element model could be used for control and state estimation purposes. For a typical supercapacitor charging profile, the numerical solutions from both models closely match experimental voltage and current data. However, when the electrolyte is dilute or where there is a long charging time, a noticeable difference between the numerical solutions of the two models is observed. Electrical impedance spectroscopy simulations show that the capacitance of the two models rapidly decreases when the frequency of the perturbation current exceeds an upper threshold.
spellingShingle Drummond, R
Howey, D
Duncan, S
Low-order mathematical modelling of electric double layer supercapacitors using spectral methods
title Low-order mathematical modelling of electric double layer supercapacitors using spectral methods
title_full Low-order mathematical modelling of electric double layer supercapacitors using spectral methods
title_fullStr Low-order mathematical modelling of electric double layer supercapacitors using spectral methods
title_full_unstemmed Low-order mathematical modelling of electric double layer supercapacitors using spectral methods
title_short Low-order mathematical modelling of electric double layer supercapacitors using spectral methods
title_sort low order mathematical modelling of electric double layer supercapacitors using spectral methods
work_keys_str_mv AT drummondr lowordermathematicalmodellingofelectricdoublelayersupercapacitorsusingspectralmethods
AT howeyd lowordermathematicalmodellingofelectricdoublelayersupercapacitorsusingspectralmethods
AT duncans lowordermathematicalmodellingofelectricdoublelayersupercapacitorsusingspectralmethods