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 an 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 a side opposite to the solid electrolyte layer, the second portion being located on the solid electrolyte layer side. A first ratio of an La concentration to an Sr concentration detected at the first portion through Auger electron spectroscopy is at least 1.1 times a second ratio of an La concentration to an Sr concentration detected at the second portion through Auger electron spectroscopy.

A microgrid system includes first and second DC power sources electrically connected to respective first and second DC electrical power busses, a first uninterruptable power module electrically connected to the first DC electrical power bus and configured to be connected to an alternating current (AC) load, a second uninterruptable power module electrically connected to the second DC electrical power bus and configured to be connected to the AC load, a first bi-directional AC/DC inverter having a DC end and an AC end, where the first DC electrical power bus is connected to the DC end of the first bi-directional AC/DC inverter, a second bi-directional AC/DC inverter having DC and AC ends, where the second DC electrical power bus is connected to the DC end of the second bi-directional AC/DC inverter, and an AC electrical power bus electrically connected to the first and second bi-directional AC/DC inverters at their AC ends.

Solid-state energy harvesters comprising layers of metal suboxides and cerium dioxide utilizing a solid-state electrolyte to produce power and methods of making and using the same are provided. The solid-state energy harvester may have two or three electrodes per cell and produces power in the presence of water vapor and oxygen.

Articles and methods including additives in electrochemical cells, are generally provided. As described herein, such electrochemical cells may comprise an anode, a cathode, an electrolyte, and optionally a separator. In some embodiments, at least one of the anode, the cathode, the electrolyte, and/or the optional separator may comprise an additive and/or additive precursor. For instance, in some cases, the electrochemical cell comprises an electrolyte and an additive and/or additive precursor that is soluble with and/or is present in the electrolyte. In some embodiments, the additive precursor comprises a disulfide bond. In certain embodiments, the additive is a carbon disulfide salt. In some cases, the electrolyte may comprise a nitrate.

A thermally integrated hotbox apparatus combining a steam reformer, a plurality of solid oxide fuel cell (SOFC) stacks, a plurality of oxidant manifolds, and at least one heat extractor. The steam reformer occupies a central position in the hotbox, around which are disposed in spaced-apart relation a plurality of SOFC stacks. A burner may be associated with the steam reformer, either within or outside the hotbox. An oxidant manifold is disposed between each pair of adjacent SOFC stacks. A heat exchanger is incorporated between an SOFC stack and an oxygen manifold. The hotbox design optimally captures thermal heat from the SOFC stacks for use in producing steam and operating the endothermic steam reformer. The apparatus reduces duty cycle of the burner, which produces heat and steam needed for operation of the endothermic steam reformer.

A composite member includes a base member and a covering layer. The base member includes a first surface not exposed to an oxidizing atmosphere and contains chromium. The covering layer covers the first surface and includes a first outer surface that is not exposed to the oxidizing atmosphere. At least one of the base member and the covering layer includes an exposed surface that is exposed to the oxidizing atmosphere. The surface roughness of the exposed surface is different from the surface roughness of the first surface or the first outer surface.

A method of forming an interlayer of a solid oxide cell unit on the surface of a substrate may include: providing a base interlayer solution comprising a solution of a soluble salt precursor of a metal oxide (crystalline) ceramic and crystalline nanoparticles, depositing the base interlayer solution onto the surface of the substrate, drying the base interlayer solution to define a nanocomposite sub-layer of the soluble salt precursor and nanoparticles, heating the sub-layer to decompose it and form a film of metal oxide comprising nanoparticles on the surface, and firing the substrate with the film on the metal surface, to form a nanocomposite crystalline layer.

A SOC stack has interconnects with a maximum distance between the contact points which are designed to compensate for pressure difference between one side of the interconnect to the other side.

An interconnector for a solid-oxide electrochemical cell stack of the embodiment includes: a metal base containing an iron-based alloy containing chromium; and a protective film provided on a surface of the metal base. The protective film includes a protective film body containing at least one selected from a spinel oxide and a perovskite oxide, and dispersed phases scattered in the protective film body and containing an oxide of at least one element selected from the group consisting of rare earth elements and zirconium.

A fuel cell system including: an electrochemical pump including a first anode, a first cathode, and a first electrolyte membrane including a proton conductive oxide, the electrochemical pump separating hydrogen from a gas containing the hydrogen, and a solid oxide fuel cell that includes a second anode, a second cathode, and a second electrolyte membrane including a solid oxide electrolyte, and that generates electricity by reacting a fuel gas and an oxidant gas with each other.