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An autonomous power supply device based on a 30 W fuel cell (FC) stack and a hydrolysis-type hydrogen generator were developed. Creation of this device included construction of a unit for hydrogen generation, development of an electronic control unit for the operation of the device, testing and optimizing the overall performance. The hydrolysis of NaBH4 was catalyzed by Pt-based catalysts and was studied for different reactor configurations and reagent concentrations. The flat type of the reactor, Pt-catalyst deposited on cordierite as a support and 10 % solution of NaBH4 proved to be the most efficient when generating H2 for the use in the 30W FC. A developed electronic control unit effectively regulates the hydrolysis reaction rate and provides the required hydrogen supply to the FC. A Li-ion battery being used to start the work of the developed system. One important feature of the developed electronic system is the use of the supercapacitors enabling smoothening of the periodic variations of the generated power. The created hydrolysis unit integrated with the FC provides stable power supply for at least 9 hours from 1 refueling (Uconst = 12 V, I = 0-2.5 A, Nominal Power = 30 W). The specific generated power of the system when accounting its weight and volume is similar to the analogues described in the reference data, while the electronic circuit enables its stable and efficient performance satisfying the consumer needs for autonomous energy supply when a stationary electrical grid is not available.

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Aluminum is a promising metal for creating energy-storing substances (ESS) on its basis for hydrogen evolution from water as a result of its of activating aluminum and providing it with the ability to react with water, special attention is paid to methods of alloying it with additions of low-melting metals and alloys, in particular, the eutectic alloy of gallium, indium and tin is perspective alloy for alloying aluminum and obtaining ESS, capable of releasing hydrogen from water without additional heating. The temperature at which stable interaction of aluminum activated by low-melting metals and alloys with water begins to be determined by the temperature at which alloying metals on the surface of aluminum crystallites become liquid. The melting point of the four-component Ga61In25Sn13Zn1 eutectic is about 3 °C, what is about 8 °C lower than the melting point of the Ga-In-Sn eutectic. Therefore, in this work, aluminum was activated by the eutectic alloy of gallium, indium and tin, as well as zinc, and the regularities of the hydrolysis of the obtained EAPs were investigated. Comparative volumetric determinations of hydrogen, which was released during the hydrolysis of 95 wt.% Al + 5 wt.% Ga-In-Sn eutectic and 92 wt.% Al + 5 wt.% Ga-In-Sn eutectic + 3 wt.% Zn alloys, showed that the introduction of zinc into activated aluminum led to a significant acceleration of hydrogen evolution from water at low temperatures (25 and 40 °C). The effective rate constants of hydrolysis of the zinc-doped alloy, calculated using the modified Prout-Tompkins equation, were 1.33, 1.75, 2.19, and 2.58 min-1 at temperatures of 25, 40, 55, and 70 °C, respectively. The effective activation energy of the process, calculated from the temperature dependence of the effective rate constant, was 12.6 kJ·mol-1, which indicates diffuse control of the hydrolysis rate. An analysis of the X-ray diffraction pattern of the products of the hydrolysis of 92 wt.% Al + 5 wt.% Ga-In-Sn eutectic + 3 wt.% Zn alloy at the temperature of 55 °C showed that they contain boehmite, baerite and small amounts of alloying metals.