A system for deploying an aircraft emergency evacuation slide or other inflatable device utilizes an inflation gas that is stored in a partially liquified state. The inflation gas includes a gaseous compound, preferably nitrous oxide, that is capable of undergoing an exothermic thermal decomposition, which gives off heat and produces a greater number moles of inflation gas than the number of moles of gas stored. The increase in moles of gas allows a greater inflation volume for a given weight of stored gas, while the exothermic decomposition produces additional heat that offsets, to some extent, the endothermic boiling and expansion of the liquified stored gas.