A electrochemical direct heat to electricity converter having a low temperature membrane electrode assembly array and a high temperature membrane electrode assembly array is provided. Additional cells are provided in the low temperature membrane electrode assembly array, which causes an additional amount of the working fluid, namely hydrogen, to be pumped to the high pressure side of the converter. The additional pumped hydrogen compensates for the molecular hydrogen diffusion that occurs through the membranes of the membrane electrode assembly arrays. The MEA cells may be actuated independently by a controller to compensate for hydrogen diffusion

A heat to electricity converter including a working fluid and a pair of membrane electrode assemblies (MEA) is provided. Each MEA includes a pair of electrodes which are electron conductive and permeable to the working fluid, and a thin film electrolyte membrane sandwiched between the electrodes. The membrane is conductive of ions of the working fluid and has a thickness of 0.03 μm to 10 μm. At least one electrode of each MEA includes a non-porous and dense metal. One electrode of each MEA is in contact with the working fluid at a first, higher pressure, while the other electrode is in contact with the working fluid at a second, lower pressure. The first MEA is configured to compress the working fluid from the second pressure to the first pressure, while the second MEA is configured to expand the working fluid from the first pressure to the second pressure.

A electrochemical direct heat to electricity converter having a low temperature membrane electrode assembly array and a high temperature membrane electrode assembly array is provided. Additional cells are provided in the low temperature membrane electrode assembly array, which causes an additional amount of the working fluid, namely hydrogen, to be pumped to the high pressure side of the converter. The additional pumped hydrogen compensates for the molecular hydrogen diffusion that occurs through the membranes of the membrane electrode assembly arrays. The MEA cells may be actuated independently by a controller to compensate for hydrogen diffusion.

The present invention proposes a thermochemical battery cycle, termed a Benzene Battery cycle, for efficiently storing electric and/or thermal energy for later and/or distant use. The methods and apparatus herein proposed utilize reversible endothermic fluid and exothermic fluid thermochemical means for efficiently storing H2 in a liquid state at STP. The present invention is generally based on the technology disclosed in U.S. Pat. Nos. 3,225,538, 3,067,594, and 3,871,179, wherein techniques are described for creating a unique thermochemical cycle, termed the Bland/Ewing Cycle (B/E Cycle) after the co-inventors, involving “molecular expansion” and “molecular compression”. The present invention is also based on US Patent Application #18-0954634 which proposes optimizing endothermic and exothermic “segments” for the creation of either Combined Heat and Power (CHP) or Combined Cycle (CC) applications.

A electrochemical direct heat to electricity converter having a low temperature membrane electrode assembly array and a high temperature membrane electrode assembly array is provided. Additional cells are provided in the low temperature membrane electrode assembly array, which causes an additional amount of the working fluid, namely hydrogen, to be pumped to the high pressure side of the converter. The additional pumped hydrogen compensates for the molecular hydrogen diffusion that occurs through the membranes of the membrane electrode assembly arrays. The MEA cells may be actuated independently by a controller to compensate for hydrogen diffusion.

An electrode for use in an all-iron redox flow battery is provided. In one example, the electrode may include a plastic mesh; and a coating on the plastic mesh. The coating may be a hydrophilic coating or a conductive coating and the electrode may have an electrode reaction potential is less than 0.8V. Further, a method of manufacturing a coated plastic mesh electrode for use in an all-iron redox flow battery is provided. In one example method, the steps include fabricating a plastic mesh, treating the plastic mesh by applying a solvent treatment or a plasma treatment or a mechanical abrasion treatment; coating the plastic mesh with a material selected from: carbon inks, metal oxides, and hydrophilic polymers.

A direct heat to electricity engine includes solid state electrodes of an electrochemically active material that has an electrochemical reaction potential that is temperature dependent. The electrodes are configured in combination with electrolyte separators to form membrane electrode assemblies. The membrane electrode assemblies are grouped into pairs, whereby each membrane electrode assembly of a given pair is ionically and electronically interconnected with the other. One membrane electrode assembly of a given pair is coupled to a heat source with the other to a heat sink. One membrane electrode assembly of the pair is electrically discharged while the other is electrically charged, whereby the net and relative charge between the two remains constant because of the electronic and ionic interconnection and the difference in temperature of the membrane electrode assemblies, and thereby voltage, results in net power generation.

A thermoelectric generator includes a voltage source including a thermoelectric element, a starting circuit connected to the voltage source, a DC to DC converter circuit connected to the voltage source, an output connected to the starting circuit and connected to the DC to DC converter circuit, and a controller having an input connected to the voltage source, and outputs connected to the starting circuit and to the DC to DC converter circuit. The controller deactivates the starting circuit and activates the DC to DC converter circuit when a voltage at the output or when a voltage provided by the voltage source rises above a predefined upper voltage threshold. Additionally, the controller reactivates the starting circuit and deactivates the DC to DC converter circuit when a voltage at the output or when a voltage provided by the voltage source drops below a predefined lower voltage threshold.

A hydride heat engine produces electricity from a heat source, such as a solar heater. A plurality of metal hydride reservoirs are heated by the heating device and a working fluid comprises hydrogen is incrementally move from one metal hydride reservoir to a success metal hydride reservoir. The working fluid is passed, at a high pressure, from the last of the plurality of metal hydride reservoirs to an electro-chemical-expander. The electro-chemical-expander has an anode, a cathode, and an ionomer therebetween. The hydrogen is passed from the anode at high pressure to the cathode at lower pressure and electricity is generated. The solar heater may be a solar water heater and the hot water may heat the metal hydride reservoirs to move the hydrogen. The working fluid may move in a closed loop.

An electrode for use in an all-iron redox flow battery is provided. In one example, the electrode may include a plastic mesh; and a coating on the plastic mesh. The coating may be a hydrophilic coating or a conductive coating and the electrode may have an electrode reaction potential is less than 0.8V. Further, a method of manufacturing a coated plastic mesh electrode for use in an all-iron redox flow battery is provided. In one example method, the steps include fabricating a plastic mesh, treating the plastic mesh by applying a solvent treatment or a plasma treatment or a mechanical abrasion treatment; coating the plastic mesh with a material selected from: carbon inks, metal oxides, and hydrophilic polymers.