A proton conductor contains a metal oxide that has a perovskite structure and that is represented by formula (1): A.sub.xB.sub.1-yM.sub.yO.sub.3-, where an element A is at least one element selected from the group consisting of Ba, Ca, and Sr, an element B is at least one element selected from the group consisting of Ce and Zr, an element M is at least one element selected from the group consisting of Y, Yb, Er, Ho, Tm, Gd, In, and Sc, indicates an oxygen deficiency amount, and 0.95x1 and 0<y0.5 are satisfied.

A novel electrochemical cell is disclosed in multiple embodiments. The instant invention relates to an electrochemical cell design. In one embodiment, the cell design can electrolyze water into pressurized hydrogen using low-cost materials. In another embodiment, the cell design can convert hydrogen and oxygen into electricity. In another embodiment, the cell design can electrolyze water into hydrogen and oxygen for storage, then later convert the stored hydrogen and oxygen back into electricity and water.

In general, the present disclosure is directed to methods to produce stable oxygen electrodes for use in energy storage applications such as fuel cells. Aspects of the disclosure can provide improved stability, especially for oxygen electrodes including strontium, which can broaden applications and reduce costs to improve economic feasibility. Embodiments of the disclosure can include methods for producing oxygen electrodes, compositions of stabilizing coatings that can be applied to electrodes to yield a more stable oxygen electrode, and fuel cells incorporating oxygen electrodes produced according to the disclosure. In particular, the disclosure is directed to a finding that a conformal coating can be achieved by calcining a composition including a strontium salt, a cobalt salt, and a tantalum compound on a base electrode, the base electrode having an elemental composition including strontium.

The invention relates to a rechargeable battery system 1, comprising: at least one electrochemical cell 2 adapted for in charge mode to convert one or more gaseous electrochemical reaction reactant(s) 3 into one or more gaseous electrochemical reaction product(s) 4, at least one storage arrangement 5 for storing said gaseous electrochemical reaction reactants and products, wherein at least one of the gaseous electrochemical reaction product(s) 4 is converted to and stored as at least one chemical reaction product(s) 7,11, where said chemical reaction product(s) 7,11 has a lower gas pressure upon formation than the corresponding gaseous electrochemical reaction product(s) 4, a first fluid communication system 12 between the at least one cell and the at least one storage arrangement 5, wherein the first fluid communication system is configured to form a closed system within the battery system, whereby the battery system is adapted to generate an automatic gas flow between the at least one storage arrangement 5 and cell 2.

Provided is a rechargeable electrochemical cell system for generating electrical current using a fuel and an oxidant. The system includes a plurality of electrochemical cells. A controller is configured to apply an electrical current between charging electrode(s) and a fuel electrode with the charging electrode(s) functioning as an anode and the fuel electrode functioning as a cathode, such that reducible metal fuel ions in the ionically conductive medium are reduced and electrodeposited as metal fuel in oxidizable form on the fuel electrode. The controller may selectively apply current to a charging electrode and third electrode between fuel electrodes of separate cells to increase uniformity of the metal fuel being electrodeposited on the fuel electrode. The controller controls a number of switches to apply current to the electrodes and select different modes for the system. Also provided are methods for charging and discharging an electrochemical cell system, and selecting different modes.

This hydrogen-oxygen reaction device includes a reaction vessel including a reaction region filled with a reaction catalyst which promotes a reaction between hydrogen and oxygen, an introduction portion which introduces an hydrogen-oxygen mixed gas having hydrogen or oxygen as a main component into the reaction vessel, a water vapor pipe of which one end portion is inserted into the reaction vessel and which includes a region in contact with the reaction region with at least a part of the region in contact with the reaction region being formed of a water vapor permeable membrane, a discharge portion through which a gas in the reaction vessel is discharged to an outside, and a cooling portion which cools the water vapor pipe outside the reaction vessel.

A system produces inert gas and generates electrical power with an electrochemical cell with an anode and a cathode separated by a proton transfer medium separator. The anode includes an oxygen evolution reaction catalyst and a hydrogen oxidation reaction catalyst, and the system is operated in alternate modes: a first mode in which water is electrolyzed at the anode with an oxygen evolution reaction catalyst to form protons and oxygen, the protons are transported across the separator to the cathode and reacted with oxygen at the cathode, and an inerting gas depleted of oxygen is discharged from the cathode; and a second mode in which protons and electrons are produced from a fuel at the anode with a hydrogen oxidation reaction catalyst, protons are transported across the separator to the cathode, and electrons are transported to the cathode through an electrical circuit to produce electrical power.

A system is disclosed for providing inerting gas to a protected space, and also providing electrical power. The system includes an electrochemical cell comprising a cathode and an anode separated by a separator comprising a proton transfer medium. Inerting gas is produced at the cathode. A fuel source comprising methanol or formaldehyde or ethanol and a water source are each in controllable operative fluid communication with the anode. A controller is configured to alternatively operate the system in a first mode of operation where water is directed to the anode fluid flow path inlet and electric power is directed from a power source to the electrochemical cell, and in a second mode of operation in which the fuel is directed from the fuel source to the anode fluid flow path inlet and electric power is directed from the electrochemical cell to the power sink.

A vehicle includes: a power storage device; a regenerative fuel cell including a water electrolysis device and a fuel cell; a motor generator configured to be driven using electric power of at least one of the power storage device and the fuel cell; a driving wheel configured to be driven by the motor generator; and a control device configured to perform regeneration control of generating regenerative electric power by the motor generator at a time of braking of the vehicle. The control device is configured to supply the regenerative electric power to the water electrolysis device when an SOC of the power storage device is equal to or greater than a predetermined value at a time of performing the regeneration control.

A catalyst of an embodiment includes a porous structure including aggregates of particles containing Ru and metal atoms M different from Ru. The particles are a metal oxide. A metal atom ratio of the metal atom M in a surface region of the porous structure is higher than that of the metal atom M in the porous structure as a whole.