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The need for reliable renewable energy storage devices has become increasingly important. However, the performance of current electrochemical battery and supercapacitor devices is limited by either low energy or power densities and short lifespans. Recently, a 2D class of transition metal carbides and nitrides known as MXenes have emerged which demonstrates promise as future materials in energy storage devices. In this presentation, we report the synthesis and characterization of multilayer Ti₄N₃T_x MXene in various aqueous electrolytes. We demonstrate that Ti₄N₃T_x can be electrochemically activated through continuous cation intercalation over a 10-day period (15,000 cycles) using cyclic voltammetry. A wide operating window of 2V is maintained throughout activation. After activation, capacitance increases by 240%, 220%, and 125% in 1M H₂SO₄, 1M MgSO₄, and 1M KOH, respectively and reaches over 575 F g^-1 at 2 mV s^-1 in H₂SO₄. Moreover, activation in H₂SO₄ electrolyte leads to a switch in the charge storage mechanism from capacitor to capacitor-battery hybrid behavior as a result of hydronium ion intercalation accompanied by changes in the oxidation state of Ti. To date, this is one of the most electrochemically stable MXenes reported in aqueous electrolytes and provides the highest capacitance universally across different pH environments among MXenes. These findings may offer a new and reliable option for reliable energy storage devices with potential applications in large-scale grid storage and electric vehicles.