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FIB-SEM, XPS, TOF-SIMS and electrochemical methods have been used for the characterization of physical properties and chemical composition of microporous carbide derived carbon electrodes, prepared from TiC at 950 • C (noted as TiC-CDC) after 40000 charge/discharge cycles. Changes in surface chemical composition of TiC-CDC electrodes, includes partial contamination with reaction intermediates (F 2 , CH − , CHO − , CN − , organic radicals), and Al current collectors, like partial dissolution of Al from positively charged electrode and deposition of Al onto the negatively charged TiC-CDC electrode surface, have been analyzed. The values of gravimetric energy (taking into consideration the active TiC-CDC material weight only) calculated before and after constant current charge/discharge cycling at cell voltage 3.4 V are quite similar (35 and 34 W h kg −1 , respectively). At starting moment the gravimetric power was practically 1.4 times higher (195 kW kg −1 , 146 kW dm −3 ) than that calculated after 40000 charge/discharge cycles (144 kW kg −1 , 104 kW dm −3 ). The characteristic relaxation time constant (0.94 and 1.23 s, respectively) increases somewhat in accordance with the decrease of power density during long-lasting cycling at higher cell voltage range from 0.2 to 3.4 V.

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