Abstract: In order to ensure the safety and reliability during use of the lithium-ion hybrid capacitor,it is necessary to monitor and manage its operation process.In this process,modeling and parameter idenpngication methods are indispensable.In this article,the 2nd-order RC equivalent circuit model of the Thevenin’s equivalent circuit model was used for capacitor’s dynamic performance modeling.A method for idenpngying the parameters of a lithium-ion hybrid capacitor model based on a recursive least square method with forgetting factor is given,which realized the on-line idenpngication of its open-circuit voltage,ohmic internal resistance,and polarization internal resistance.The work can provide basic method and reference for the state estimation and life prediction of lithium-ion hybrid capacitor.

Key words: electric vehicle, lithium-ion hybrid capacitor, recursive least squares method with forgetting factor, on-line, parameter idenpngication