Топливные элементы

The article is about operating features of aluminium-water hydrogen microgenerators designed for use in portable power sources developed in GIHT RAS. Paper presents experimental data on the factors, which have an influence on hydrogen production rate, rate control ways and combined hydrogen microgenerator and air-hydrogen fuel cell stack testing in close to practical work conditions.

To increase structural stability under cycling, LiMn₂O₄ was modified by co-doping with 3d-metals (Co, Ni, Cr, Fe) and lithium. The synthesis of spinels was realized by preliminary mechanical activation of reagent mixture and subsequent heat treatment at 750°С.

The method of thermodynamic simulation was used to establish equilibrium products of chemical interactions in the systems lithium metal – solid electrolyte (SE). Calculations were performed at 25–165^o C for Li₆BeO₄, LiYO₂, LiScO₂, Li₅SiN₃, Li₈SiN₄, Li₃AlN₂, Li₂SO₄, Li₂ZrO₃, Li₄ZrO₄, Li₈ZrO₆ and Li₅AlO₄ solid electrolytes.

Some regularities of the structure formation of carbon-black-dispersed teflon gas diffusion layers of air (oxygen) electrodes of fuel cells and their initial components in process their making have been studied by the high-performance method called Dynamic Desorption Porometry and the BET (at the temperature of liquid nitrogen). The investigated input objects were Acetylene Gas detonation Black (AB) and Ketjen Black (KB). The pore size distribution of initial and hydrophobizated AB, KB and GDL on their base have been obtained.

The influence of partial substitution of Zr⁴⁺ ions for Ge⁴⁺ ions at high conduction solid electrolyte Li_3.75Ge_0.75V_0.25O₄ was investigated. It was established that introduction of zirconium ions leads to noticable increasing of electrolyte conductivity and decreasing of activation energy.

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This paper presents polarization characteristics of porous gas diffusion cathodes prepared from LaLi0.1M0.1Fe0.8O3-d (M = Fe, Co, Ni) oxides with a perovskite related structure and Li0.1Ni0.9O oxide with a rock salt structure. The characteristics were measured in the laboratory scale fuel cell in the temperature range 820–1000 K. It has been shown that electrochemical activity of the cathodes with Co and Ni additives exceeds the activity of the Li0.1Ni0.9O cathode below 970 K.

Features of current generation processes in MEA of hydrogen-air (oxygen) fuel cells with proton-conducting (acidic) and anion-conducting (alkaline) solid polymer electrolytes were compared. Certain parameters of electrode reactions and characteristics of electrolytes and interaction effects of MEA’s components in FC operation and also destabilizing factors which deriving direct from current flow as well as from presence of impurities in the fuel and oxidant were discussed.

New mechanisms of oxygen reduction on perovskite related oxides LaL_i0.1M_0.1Fe_0.8O_3-d (M = Fe, Co, Ni) and a rock salt type oxide Li_0.1Ni_0.9O have been proposed. Based on these mechanisms, a comparison of catalytic activity of the oxides in the temperature range 820–1000 K has been done. It has been shown that catalytic activity of LaLi0.Co0.1Fe0.8O3-d oxide exceeds the activity of Li0.1Ni0.9O below 970 K

This work considers the application of graphene while forming the electrodes in biofuel cells. Graphene displays a number of important characteristics including first of all good mechanical properties, high thermal conductivity, high specific surface area, biocompatibility, structural peculiarities of a molecule, is available for chemical modification of the structure. Fabrication, properties of graphene and its oxide were considered and the peculiarities of the application of graphene as a basic material for electrodes in biofuel cells are also discussed.