There are provided a ferrite stainless steel for a polymer fuel cell separator having excellent corrosion resistance and interfacial contact resistance under an operating environment of a polymer fuel cell, and a preparation method of the stainless steel. A stainless steel includes C: 0.02 wt % or less, N: 0.02 wt % or less, Si: 0.4 wt % or less, Mn: 0.2 wt % or less, P: 0.04 wt % or less, S: 0.02 wt % or less, Cr: 25.0 to 32.0 wt %, Cu: 0 to 2.0 wt %, Ni: 0.8 wt % or less, Ti: 0.5 wt % or less, Nb: 0.5 wt % or less, waste Fe and inevitably contained elements. A preparation method of the stainless steel having a second passive film formed on a surface thereof includes forming a first passive film on the surface of the stainless steel by bright-annealing or annealing-pickling the stainless steel; removing the first passive film by pickling the stainless steel in a 10 to 20 wt % sulfuric acid solution at a temperature of 50 to 75° C. for a predetermined time; water-washing the stainless steel; and forming the second passive film by performing a passivation treatment on the stainless steel in the mixture of a 10 to 20 wt % nitric acid and a 1 to 10 wt % fluorine acid at a temperature of 40 to 60° C. for the predetermined time. Accordingly, it is possible to prepare a stainless steel having reduced elution resistance and excellent corrosion resistance and to produce a stainless steel for a polymer fuel cell separator, which has low interfacial contact resistance and excellent long-term performance even under a fuel cell operating condition of 60 to 150° C. and various surface roughness conditions.

Layers for a bipolar plates are disclosed, as well as bipolar plates including the layers and fuel cells and/or electrolyzers including the bipolar plates. The layer may include a homogeneous or heterogeneous solid metallic solution or compound which either contains a first chemical element from the group of the noble metals in the form of iridium; or contains a first chemical element from the group of the noble metals in the form of iridium and a second chemical element from the group of the noble metals in the form of ruthenium. The layer may also include at least one further nonmetallic chemical element from the group consisting of nitrogen, carbon, boron, fluorine, and hydrogen.

Layers for a bipolar plates are disclosed, as well as bipolar plates including the layers and fuel cells and/or electrolyzers including the bipolar plates. The layer may include a homogeneous or heterogeneous solid metallic solution or compound which either contains a first chemical element from the group of the noble metals in the form of iridium; or contains a first chemical element from the group of the noble metals in the form of iridium and a second chemical element from the group of the noble metals in the form of ruthenium. The layer may also include at least one further nonmetallic chemical element from the group consisting of nitrogen, carbon, boron, fluorine, and hydrogen.

The present specification relates to an interconnect for a solid oxide fuel cell, a method for preparing the same, and a solid oxide fuel cell.

The present specification relates to an interconnect for a solid oxide fuel cell, a method for preparing the same, and a solid oxide fuel cell.

A fuel cell separator having high corrosion resistance and electrical conductivity is provided. This fuel cell separator includes, on a substrate, a composite film containing an antimony-doped tin oxide and a tin-doped indium oxide, in which an element ratio of tin to indium (Sn/In) in the composite film is 1.4 or smaller.

The present disclosure relates to a fuel cell stack having a cathode-side separator and an anode-side separator which are made of different materials to prevent performance degradation of stacks and corrosion and damage of components. A fuel cell stack according to exemplary embodiments of the present disclosure may have multiple unit cells stacked therein, in which each unit cell of the multiple unit cells may include: a membrane electrode assembly (MEA); a pair of gas diffusion layers (GDLs) disposed on opposite surfaces of the MEA; and an anode-side separator and a cathode-side separator disposed to face each other, the MEA and the pair of GDLs being disposed therebetween, in which the cathode-side separator has a corrosion resistance higher than a corrosion resistance of the anode-side separator.

An electrochemical device includes an electrolyte membrane, an anode disposed on a first main surface of the electrolyte membrane, a cathode disposed on a second main surface of the electrolyte membrane, an anode separator disposed on the anode, and a cathode separator disposed on the cathode. At least one of the anode separator or the cathode separator includes a metal substrate sheet and a conductive layer disposed on the metal substrate sheet and containing a metal oxide and a metal hydroxide.

A lithium battery and method for fabricating the same are provided herein. The battery cathode comprises a carbon structure filled with a catalyst, such as palladium-catalyst-filled carbon nanotubes (CNTs). The carbon structure provides a barrier between the catalyst and the electrolyte providing an increased stability of the electrolyte during both discharging and charging of a battery.

A lamellar structure graphite foil is used as a material for a separator for a fuel cell, and a hydrophobic layer is formed by impregnation on flow-field channels of the graphite foil. Such a separator is manufactured by forming the flow field channel by etching the graphite foil formed with the mask pattern thereon and forming a hydrophobic layer by impregnation. According to such a separator, performance of a fuel cell stack is enhanced and the manufacturing process of a separator is simplified.