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The management of proton conductivity in the protic ionic liquidimidazolium bis(trifluoromethylsulfonyl)imide ([Im][TFSI]) is investigatedvia the use of quasi-elastic neutron scattering (QENS) and pulsed-fieldgradient NMR. The introduction of excess neutral imidazole to [Im][TFSI]leads to enhanced conductivity. We find that proton dynamics in [Im][TFSI]with excess imidazole are characterized by proton hopping that isencompassed in the slower of two translational processes, as identifiedby QENS. This relatively slow process contributes to long-range diffusionmore than the faster process. NMR diffusion measurements show thatproton hopping decreases with increasing temperature, but significantproton hopping persists even at the maximum experimental temperatureof 120 °C. This, in combination with minimal ion aggregation,leads to high proton conductivity and a high proton transference numberover a wide temperature range. [ABSTRACT FROM AUTHOR]