An electrochemical cell includes a fuel electrode, an air electrode containing a perovskite type oxide as a main component, the perovskite type oxide being represented by a general formula ABO.sub.3 and containing La and Sr at the A site, and a solid electrolyte layer arranged between the fuel electrode and the air electrode. The air electrode includes a first portion and a second portion, the first portion being located on the most upstream side in a flow direction of an oxidant gas that flows through a surface of the air electrode, the second portion being located on the most downstream side in the flow direction. A first ratio of a La concentration to a Sr concentration detected at the first portion through Auger electron spectroscopy is at least 1.1 times a second ratio of a La concentration to a Sr concentration detected at the second portion through Auger electron spectroscopy.

[Problems] To easily and efficiently manufacture a catalyst layer having high catalytic activity and to easily manufacture a fuel cell having high power generation efficiency. [Solution] An apparatus for forming a catalyst layer 3 for a fuel cell on an electrolyte film (application object) 2, the apparatus including: a holding portion 6 that holds a sheet-shaped electrolyte film 2, an application portion 7 that applies a catalyst ink 5 for forming the catalyst layer 3 on at least one side of the electrolyte film 2 held by the holding portion 6, a chamber portion 8 that is capable of forming a space 55 including the holding portion 6, and a suction portion 9 that depressurizes the inside of the space 55 formed by the chamber portion 8 so as to dry the catalyst ink 5.

[Problems] To easily and efficiently manufacture a catalyst layer having high catalytic activity and to easily manufacture a fuel cell having high power generation efficiency. [Solution] An apparatus for forming a catalyst layer 3 for a fuel cell on an electrolyte film (application object) 2, the apparatus including: a holding portion 6 that holds a sheet-shaped electrolyte film 2, an application portion 7 that applies a catalyst ink 5 for forming the catalyst layer 3 on at least one side of the electrolyte film 2 held by the holding portion 6, a chamber portion 8 that is capable of forming a space 55 including the holding portion 6, and a suction portion 9 that depressurizes the inside of the space 55 formed by the chamber portion 8 so as to dry the catalyst ink 5.

Provided is an electrolyte for a flow battery, the electrolyte being supplied to a flow battery, in which a total concentration of ions of elements of groups 1 to 8 and ions of elements of groups 13 to 16 in the fifth period of the periodic table, and ions of elements of groups 1, 2, and 4 to 8 and ions of elements of groups 13 to 15 in the sixth period of the periodic table, the ions being impurity element ions involved in generation of a gas containing elemental hydrogen, is 610 mg/L or less, a concentration of vanadium ions is 1 mol/L or more and 3 mol/L or less, a concentration of free sulfuric acid is 1 mol/L or more and 4 mol/L or less, a concentration of phosphoric acid is 1.0×10.sup.−4 mol/L or more and 7.1×10.sup.−1 mol/L or less, a concentration of ammonium is 20 mg/L or less, and a concentration of silicon is 40 mg/L or less. When a charging and discharging test is performed by circulating and supplying the electrolyte to the flow battery under specific conditions, a generation rate of hydrogen is less than 10 cc/h/m.sup.2 and a generation rate of hydrogen sulfide is less than 5.0×10.sup.−3 cc/h/m.sup.2, the hydrogen and the hydrogen sulfide being generated in a negative electrode of the flow battery during charging and discharging.

Provided is an electrolyte for a flow battery, the electrolyte being supplied to a flow battery, in which a total concentration of ions of elements of groups 1 to 8 and ions of elements of groups 13 to 16 in the fifth period of the periodic table, and ions of elements of groups 1, 2, and 4 to 8 and ions of elements of groups 13 to 15 in the sixth period of the periodic table, the ions being impurity element ions involved in generation of a gas containing elemental hydrogen, is 610 mg/L or less, a concentration of vanadium ions is 1 mol/L or more and 3 mol/L or less, a concentration of free sulfuric acid is 1 mol/L or more and 4 mol/L or less, a concentration of phosphoric acid is 1.0×10.sup.−4 mol/L or more and 7.1×10.sup.−1 mol/L or less, a concentration of ammonium is 20 mg/L or less, and a concentration of silicon is 40 mg/L or less. When a charging and discharging test is performed by circulating and supplying the electrolyte to the flow battery under specific conditions, a generation rate of hydrogen is less than 10 cc/h/m.sup.2 and a generation rate of hydrogen sulfide is less than 5.0×10.sup.−3 cc/h/m.sup.2, the hydrogen and the hydrogen sulfide being generated in a negative electrode of the flow battery during charging and discharging.

A hydrogen fuel cell forklift truck with a distributed architecture includes a frame, and, a hydrogen storage system, a fuel cell, a cooling system and an energy storage system arranged on the frame, and the fuel cell is connected with the hydrogen storage system and the energy storage system for charging the energy storage system and providing kinetic energy; the hydrogen storage system is located outside the fuel cell and exposed to the frame for supplying hydrogen to the fuel cell; the cooling system is located outside the fuel cell and connected to the fuel cell for cooling the fuel cell; the energy storage system is located outside the fuel cell and connected to the fuel cell for recovering braking energy and providing kinetic energy together with the fuel cell.

A hydrogen fuel cell forklift truck with a distributed architecture includes a frame, and, a hydrogen storage system, a fuel cell, a cooling system and an energy storage system arranged on the frame, and the fuel cell is connected with the hydrogen storage system and the energy storage system for charging the energy storage system and providing kinetic energy; the hydrogen storage system is located outside the fuel cell and exposed to the frame for supplying hydrogen to the fuel cell; the cooling system is located outside the fuel cell and connected to the fuel cell for cooling the fuel cell; the energy storage system is located outside the fuel cell and connected to the fuel cell for recovering braking energy and providing kinetic energy together with the fuel cell.

A method of manufacturing a solid oxide fuel cell stack, including alternately disposing a plurality of single fuel cells, and a plurality of interconnectors disposed alternately and holding the alternately disposed plurality of single fuel cells and plurality of interconnectors between a pair of end members, forming a space between a first end member and a first interconnector, disposing a junction member composed of an elastic member and an electrically conductive member in the space, and urging a portion of an electrically conductive member and another portion of the electrically member against the first end member and the first interconnector so that a total thickness of the portion of the electrically conductive member, the another portion of the electrically conductive member, and the elastic member prior to being disposed in the space between the first end member and the first interconnector is greater than a height of the space.

A method of manufacturing a solid oxide fuel cell stack, including alternately disposing a plurality of single fuel cells, and a plurality of interconnectors disposed alternately and holding the alternately disposed plurality of single fuel cells and plurality of interconnectors between a pair of end members, forming a space between a first end member and a first interconnector, disposing a junction member composed of an elastic member and an electrically conductive member in the space, and urging a portion of an electrically conductive member and another portion of the electrically member against the first end member and the first interconnector so that a total thickness of the portion of the electrically conductive member, the another portion of the electrically conductive member, and the elastic member prior to being disposed in the space between the first end member and the first interconnector is greater than a height of the space.

A power generation method includes providing power from a first DC power source to a load, while a second DC power source is electrically disconnected from the load, electrically connecting the second DC power source to the load and providing power from the second DC power source to the load if an output voltage from the first DC power source drops below a threshold voltage and an output voltage from the second DC power source is not below the threshold voltage, and electrically disconnecting the first DC power source from the load if an output current of the first DC power source is below a threshold current.