Fuel cells

How gas impurities influence the alkaline fuel cell performance

The work reviews the influence of gas impurities in fuel and oxidizing chemical on the alkaline oxyhydrogen fuel cell functioning. It shows that methane impurities act differently on anode and cathode, while other gases (except noble gases), including carbon monoxide, which is a poison for fuel cell with acid solution, influence the operation of alkaline fuel cell through the reaction with potassium hydroxide (KOH). Substitution electrolyte for fresh recovers fuel cell performance.

Effect of the catalyst layers structure on the pem fuel cell perfomance

Using complex models, including the solution percolation problem and electrochemical kinetics calculations are considered the features of a solid polymer fuel cell catalyst layers with a catalyst based on nanoscale carbon materials, including graphene nanowires. These calculations are consistent with the experimental data presented by optimizing the composition of the catalyst layers. It is shown that the addition of 20 wt.\% nanofibres graphene can reduce ohmic losses from the ion current and improve the performance of the fuel cell is 20%

Catalytic activity oF LaLi0.1M0.1Fe0.8O3-d (M = Fe, Co, Ni) Oxides for molten carbonate fuel cell. Part 2. Reaction Mechanisms and Catalytic Activity in (Li0.62K0.38)2CO3 Melt

New mechanisms of oxygen reduction on perovskite related oxides LaLi0.1M0.1Fe0.8O3-d (M = Fe, Co, Ni) and a rock salt type oxide Li0.1Ni0.9O 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

The application of graphene in biofuel cells

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.

Catalytic activity of LaLi0.1M0.1Fe0.8O3-d (M = Fe, Co, Ni) oxides for molten carbonate fuel cell. Part 1. Polarization Characteristics of Porous Gas Diffusion Electrodes in (Li0.62K0.38)2CO3 Melt. An Experimental Study

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.

Current-producing reactions in fuel cells with proton-conducting and anion-conducting electrolytes

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.

Electrical conductivity and thermal expansion materials on the basis of Pr2-ySryNi1-xCuxO4 (x = 0/1: y = 0/0.15) for cathode of medium temperature electrochemical devices

The phase composition, thermal coefficient of linear expansion and electrical conductivity of r1.85Sr0.15Ni1-xCuxO4 (0.0; 0.1; 0.5; 0.9 и 1), Pr2NiO4 and Pr2CuO4 are investigated at air in the temperature range 100-1000°C.
The thermal coefficient of linear expansion are in range of ((11.2–16.6)·10-6 deg-1. The TCLE of some composition close to TCLE of solid electrolyte La0.9Sr0.1Ga0.8Mg0.2O2.85 (LSGM) и Ce0.9Gd0.1O2-Δ (CGO). Pr1.85Sr0.15Ni0.1Cu0.9O4 has the highest conductivity at temperatures above 350°C.

Investigation of the high-temperature proton-exchange membrane fuel cell and calculation of the efficiency of the electrochemical power installations on its basis

A high-temperature solid polymer electrolyte fuel cell using H 3 PO 4 -doped polybenzimidazole (PBI) as proton-exchange membrane has been developed and tested. The influences of temperature (in a range between 130 and 170°C), pressure (in a range between 1 and 3 bars) and air flow rate onto fuel cell performances have been studied. A maximum output power density of 200 mW·cm-2 has been obtained. The existence of an optimum air flow rate (expressed in oxygen stoichiometric ratio) has been put into evidence. It allows an increase of the fuel cell voltage from 250 mV up to ca. 400 mV at 0.4 A·cm-2. The results of the calculation of efficiency of PBI-based electrochemical power plant using the products of natural gas conversion as a fuel are presented.

Operation life of hydrogen-oxygen fuel cell with alkaline matrix electrolyte

The paper presents the performance of domestic PHOTON hydrogen-oxygen alkaline fuel cells. The issues of FC operation life is discussed, and reasons for reversible and irreversible voltage degradation are identified. The input of FC components into irreversible part of performance degradation is estimated.

A stability study of platinized carbon black and carbon nanotubes nanocomposite as a fuel cell electrocatalyst

By cyclic voltammetry and rotating disk electrode investigated the stability of the composite catalyst Pt/C–CNT from electrochemical action through multiple changes of the electrode potential from –150 to 1000 mV vs. silver chloride reference electrode. Investigated: the dynamics of the electrochemically active surface area of platinum and electrode in whole, change of amount of quinone groups, change in density of the kinetic current reduction of air oxygen on the surface of the catalyst. With the use of the method of differential thermal analysis studied the oxidation processes and the mechanisms of change of the physicochemical properties of the material under electrochemical action.