A bipolar plate for an electrochemical reactor, including at least one anode sheet and one cathode sheet, each having an internal face and an external face, the anode and cathode sheets being in contact with each other via their internal face, each anode and cathode sheet including, on its external face, channels for circulating reactive fluids, the channels demarcating, at the internal faces of the anode and cathode sheets, cooling pipes for a flow of a heat transfer fluid, the channels of the anode and cathode sheets including alternating bosses and indentations, the bosses of the anode sheet being arranged in a staggered manner and the bosses of the cathode sheet being arranged in a staggered manner.

Systems and methods are described for producing lithium hydroxide from lithium chloride and sodium chloride through an electrolysis process. A solution of lithium hydroxide and sodium hydroxide may be produced through electrolysis of a lithium chloride and sodium chloride solution. Lithium hydroxide in the produced solution may then be crystallized and filtered out to produce substantially pure lithium hydroxide crystals.

Systems and methods are described for producing lithium hydroxide from lithium chloride and sodium chloride through an electrolysis process. A solution of lithium hydroxide and sodium hydroxide may be produced through electrolysis of a lithium chloride and sodium chloride solution. Lithium hydroxide in the produced solution may then be crystallized and filtered out to produce substantially pure lithium hydroxide crystals.

Non-proton cationic impurities are removed from the ionomer in a proton exchange membrane of an electrochemical cell and from the anode side and cathode side catalyst layers. A supply path for an anode feed to the ionomer on the anode side of the proton exchange membrane and a supply path for a cathode feed to the ionomer on the cathode side of the proton exchange membrane are provided. A regenerating fluid with acidic pH is brought into contact with the ionomer on the cathode side of the proton exchange membrane to accomplish an ion exchange of the non-proton cationic impurities with protons and thus remove the non-proton cationic impurities from the ionomer into the regenerating fluid. This removes the non-proton cationic impurities from the ionomer of the electrochemical cell without increasing the risk of corrosion and without interrupting the process of the electrochemical cell.

Non-proton cationic impurities are removed from the ionomer in a proton exchange membrane of an electrochemical cell and from the anode side and cathode side catalyst layers. A supply path for an anode feed to the ionomer on the anode side of the proton exchange membrane and a supply path for a cathode feed to the ionomer on the cathode side of the proton exchange membrane are provided. A regenerating fluid with acidic pH is brought into contact with the ionomer on the cathode side of the proton exchange membrane to accomplish an ion exchange of the non-proton cationic impurities with protons and thus remove the non-proton cationic impurities from the ionomer into the regenerating fluid. This removes the non-proton cationic impurities from the ionomer of the electrochemical cell without increasing the risk of corrosion and without interrupting the process of the electrochemical cell.

A water electrolyzer comprises an electrolyzer stack comprising at least two electrochemical cells. Each cell comprises an anion exchange membrane, a base metal anode electrocatalyst, a base metal cathode electrocatalyst, and a sufficiently long ion conduction path between adjacent cells such that shunt currents are less than 1% of the total current supplied to the stack.

A water electrolyzer comprises an electrolyzer stack comprising at least two electrochemical cells. Each cell comprises an anion exchange membrane, a base metal anode electrocatalyst, a base metal cathode electrocatalyst, and a sufficiently long ion conduction path between adjacent cells such that shunt currents are less than 1% of the total current supplied to the stack.

An embodiment electrochemical device includes a first separator including a first channel and a first land disposed in a first direction, a second separator including a second channel and a second land disposed in a second direction intersecting the first direction, the second separator being stacked on the first separator, and contact patterns provided on the first separator and disposed on the first channel so as to be in contact with the second separator.

An embodiment electrochemical device includes a first separator including a first channel and a first land disposed in a first direction, a second separator including a second channel and a second land disposed in a second direction intersecting the first direction, the second separator being stacked on the first separator, and contact patterns provided on the first separator and disposed on the first channel so as to be in contact with the second separator.

An elastic mattress being conductive and including a plurality of hill parts and valley parts, which have been formed by a curved state of the elastic mattress, wherein the hill parts include concave parts having depths smaller than heights of the hill parts, and the valley parts include projections having heights smaller than depths of the valley parts.