Abstract: A fuel cell system comprising: a fuel cell, a fuel gas supplier configured to supply fuel gas to an anode of the fuel cell, an oxidant gas supplier configured to supply oxidant gas to a cathode of the fuel cell, a humidity adjuster configured to adjust a relative humidity of the fuel gas and a relative humidity of the oxidant gas, and a controller, wherein the controller detects the relative humidity of the fuel gas at an anode inlet of the fuel cell, and the controller detects the relative humidity of the oxidant gas at a cathode outlet of the fuel cell, and wherein, based on detection results, the controller controls the humidity adjuster so that the relative humidity of the fuel gas at the anode inlet is higher than the relative humidity of the oxidant gas at the cathode outlet.

Abstract: A fuel cell system comprising: a fuel cell, a fuel gas supplier configured to supply fuel gas to an anode of the fuel cell, an oxidant gas supplier configured to supply oxidant gas to a cathode of the fuel cell, a humidity adjuster configured to adjust a relative humidity of the fuel gas and a relative humidity of the oxidant gas, and a controller, wherein the controller detects the relative humidity of the fuel gas at an anode inlet of the fuel cell, and the controller detects the relative humidity of the oxidant gas at a cathode outlet of the fuel cell, and wherein, based on detection results, the controller controls the humidity adjuster so that the relative humidity of the fuel gas at the anode inlet is higher than the relative humidity of the oxidant gas at the cathode outlet.

Abstract: A flow battery system includes a first tank including a hydrogen reactant, a second tank including a bromine electrolyte, and at least one cell including a first electrolyte side operably connected to the first tank and a second electrolyte side operably connected to the second tank. The battery system further includes a direct connection line directly connecting the first tank and the second tank and configured such that the hydrogen reactant passes between the first tank and the second tank.

Abstract: A fuel cell system comprising: a fuel cell, a fuel gas supplier configured to supply fuel gas to an anode of the fuel cell, an oxidant gas supplier configured to supply oxidant gas to a cathode of the fuel cell, a humidity adjuster configured to adjust a relative humidity of the fuel gas and a relative humidity of the oxidant gas, and a controller, wherein the controller detects the relative humidity of the fuel gas at an anode inlet of the fuel cell, and the controller detects the relative humidity of the oxidant gas at a cathode outlet of the fuel cell, and wherein, based on detection results, the controller controls the humidity adjuster so that the relative humidity of the fuel gas at the anode inlet is higher than the relative humidity of the oxidant gas at the cathode outlet.

Abstract: The Ce—H2 redox flow cell is optimized using commercially-available cell materials. Cell performance is found to be sensitive to the upper charge cutoff voltage, membrane boiling pretreatment, methanesulfonic-acid concentration, (+) electrode surface area and flow pattern, and operating temperature. Performance is relatively insensitive to membrane thickness, Cerium concentration, and all features of the (?) electrode including hydrogen flow. Cell performance appears to be limited by mass transport and kinetics in the cerium (+) electrode. Maximum discharge power of 895 mW cm?2 was observed at 60° C.; an energy efficiency of 90% was achieved at 50° C. The Ce—H2 cell is promising for energy storage assuming one can optimize Ce reaction kinetics and electrolyte.

Abstract: A flow battery system includes a first tank having a hydrogen reactant, a second tank having a bromine electrolyte, at least one cell including a hydrogen reactant side operably connected to the first tank through an ¾ feed and return system and a bromine electrolyte side operably connected to the second tank, and a crossover return system. The crossover return system includes a vessel operably connected to the ¾ feed and return system and configured to receive an effluent containing a first portion of the hydrogen reactant and a second portion of the bromine electrolyte, the vessel configured to separate the first portion from the second portion. A first return line returns the first portion of the hydrogen reactant to the first tank and a second return line returns the bromine electrolyte to the second tank.

Abstract: The Ce—H2 redox flow cell is optimized using commercially-available cell materials. Cell performance is found to be sensitive to the upper charge cutoff voltage, membrane boiling pretreatment, methanesulfonic-acid concentration, (+) electrode surface area and flow pattern, and operating temperature. Performance is relatively insensitive to membrane thickness, Cerium concentration, and all features of the (?) electrode including hydrogen flow. Cell performance appears to be limited by mass transport and kinetics in the cerium (+) electrode. Maximum discharge power of 895 mW cm?2 was observed at 60° C.; an energy efficiency of 90% was achieved at 50° C. The Ce—H2 cell is promising for energy storage assuming one can optimize Ce reaction kinetics and electrolyte.

Abstract: Various embodiments may comprise an ion exchange membrane (IEM) redox flow cell comprising a IEM, a negative electrode in contact with a reactive fluid, a liquid electrolyte comprising reactants, a positive electrode in contact with the liquid electrolyte, and a diffusion barrier layer disposed between the IEM and the positive electrode, and wherein the negative electrode is isolated from the positive electrode by the IEM.

Abstract: A flow battery system includes a first tank having a hydrogen reactant, a second tank having a bromine electrolyte, at least one cell including a hydrogen reactant side operably connected to the first tank through an ¾ feed and return system and a bromine electrolyte side operably connected to the second tank, and a crossover return system. The crossover return system includes a vessel operably connected to the ¾ feed and return system and configured to receive an effluent containing a first portion of the hydrogen reactant and a second portion of the bromine electrolyte, the vessel configured to separate the first portion from the second portion. A first return line returns the first portion of the hydrogen reactant to the first tank and a second return line returns the bromine electrolyte to the second tank.

Abstract: A flow battery system includes a first tank including a hydrogen reactant, a second tank including a bromine electrolyte, and at least one cell including a first electrolyte side operably connected to the first tank and a second electrolyte side operably connected to the second tank. The battery system further includes a direct connection line directly connecting the first tank and the second tank and configured such that the hydrogen reactant passes between the first tank and the second tank.