Abstract: A redox flow cell membrane includes a porous membrane that has a mean flow pore size of not more than 100 nm, that has a thickness of not more than 500 ?m, and that has an air flow rate of not less than 0.1 ml/s·cm2. When the redox flow cell membrane is used for a V—V-based redox flow cell, the porous membrane preferably has a mean flow pore size of not more than 30 nm.

Abstract: A redox flow battery charged and discharged by supply of a positive electrode electrolyte stored in a positive electrode tank and a negative electrode electrolyte stored in a negative electrode tank to a battery element, in which the positive electrode electrolyte contains a Mn ion as a positive electrode active material, and the positive electrode tank includes a positive electrode charging pipe opening to a position close to a liquid level of the positive electrode electrolyte in the positive electrode tank, and a positive electrode discharging pipe opening to a position close to the bottom of the positive electrode tank. This redox flow battery can include a stirring mechanism for stirring the electrolytes in the tanks, and can include a connection pipe connecting the positive electrode tank to the negative electrode tank.

Abstract: Provided are a redox flow battery (RF battery) in which a positive electrode electrolyte and a negative electrode electrolyte are supplied to a battery cell including a positive electrode, a negative electrode, and a membrane, to charge and discharge the battery, and a method of operating the RF battery. The positive electrode electrolyte contains a manganese ion, or both of a manganese ion and a titanium ion. The negative electrode electrolyte contains at least one type of metal ion selected from a titanium ion, a vanadium ion, a chromium ion, a zinc ion, and a tin ion. The RF battery can have a high electromotive force and can suppress generation of a precipitation of MnO2 by containing a titanium ion in the positive electrode electrolyte, or by being operated such that the positive electrode electrolyte has an SOC of not more than 90%.

Abstract: This invention provides a cell stack for a redox flow battery that can provide battery efficiencies with high reliability over a long term, without any adhesive bonding between a bipolar plate and electrodes. In the cell stack 1 for the redox flow battery of a cell frame 2, electrodes 3, 4 and a membrane 5 being stacked in layers, the cell frame 2 comprises a frame 2A and a bipolar plate 9 arranged inside of the frame 2A, and the electrodes 3, 4 are put into close contact with the bipolar plate 9 by a clamping force, without being adhesively bonded to the bipolar plate 9. It is preferable that when the electrodes 3, 4 are compressed to a thickness corresponding to a level difference between the frame 2A and the bipolar plate 9, repulsive force of the electrodes is in the range of more than 15 kPa to less than 150 kPa (more than 0.153 kgf/cm2 to less than 1.53 kgf/cm2).

Abstract: A redox flow cell membrane includes a porous membrane that has a mean flow pore size of not more than 100 nm, that has a thickness of not more than 500 ?m, and that has an air flow rate of not less than 0.1 ml/s·cm2. When the redox flow cell membrane is used for a V—V-based redox flow cell, the porous membrane preferably has a mean flow pore size of not more than 30 nm.

Abstract: A redox flow (RF) battery performs charge and discharge by supplying a positive electrode electrolyte and a negative electrode electrolyte to a battery cell. Each of the positive electrode electrolyte and the negative electrode electrolyte contains a vanadium (V) ion as active material. At least one of the positive electrode electrolyte and the negative electrode electrolyte further contains another metal ion, for example, a metal ion such as a manganese ion that exhibits a higher redox potential than a V ion or a metal ion such as a chromium ion that exhibits a lower redox potential than a V ion.

Abstract: A redox flow battery charged and discharged by supply of a positive electrode electrolyte stored in a positive electrode tank and a negative electrode electrolyte stored in a negative electrode tank to a battery element, in which the positive electrode electrolyte contains a Mn ion as a positive electrode active material, and the positive electrode tank includes a positive electrode charging pipe opening to a position close to a liquid level of the positive electrode electrolyte in the positive electrode tank, and a positive electrode discharging pipe opening to a position close to the bottom of the positive electrode tank. This redox flow battery can include a stirring mechanism for stirring the electrolytes in the tanks, and can include a connection pipe connecting the positive electrode tank to the negative electrode tank.

Abstract: A redox flow battery in which a positive electrode electrolyte stored in a positive electrode tank and a negative electrode electrolyte stored in a negative electrode tank are supplied to a battery element to charge and discharge the battery is provided, the positive electrode electrolyte in the redox flow battery containing a Mn ion as a positive electrode active material, the negative electrode electrolyte containing at least one of a Ti ion, a V ion, and a Cr ion as a negative electrode active material, in which the redox flow battery includes a negative-electrode-side introduction duct in communication with inside of the negative electrode tank from outside thereof, for introducing oxidizing gas into the negative electrode tank, and a supply mechanism for supplying the oxidizing gas into the negative electrode tank via the negative-electrode-side introduction duct.

Abstract: A redox flow battery in which a positive electrode electrolyte stored in a positive electrode tank and a negative electrode electrolyte stored in a negative electrode tank are supplied to a battery element to charge and discharge the battery is provided, the positive electrode electrolyte in the redox flow battery containing a Mn ion as a positive electrode active material, the negative electrode electrolyte containing at least one of a Ti ion, a V ion, and a Cr ion as a negative electrode active material, in which the redox flow battery includes a negative-electrode-side introduction duct in communication with inside of the negative electrode tank from outside thereof, for introducing oxidizing gas into the negative electrode tank, and a supply mechanism for supplying the oxidizing gas into the negative electrode tank via the negative-electrode-side introduction duct.

Abstract: Provided are a redox flow battery (RF battery) in which a positive electrode electrolyte and a negative electrode electrolyte are supplied to a battery cell including a positive electrode, a negative electrode, and a membrane, to charge and discharge the battery, and a method of operating the RF battery. The positive electrode electrolyte contains a manganese ion, or both of a manganese ion and a titanium ion. The negative electrode electrolyte contains at least one type of metal ion selected from a titanium ion, a vanadium ion, a chromium ion, a zinc ion, and a tin ion. The RF battery can have a high electromotive force and can suppress generation of a precipitation of MnO2 by containing a titanium ion in the positive electrode electrolyte, or by being operated such that the positive electrode electrolyte has an SOC of not more than 90%.

Abstract: A redox flow (RF) battery is provided that performs charge and discharge by supplying a positive electrode electrolyte and a negative electrode electrolyte to a positive electrode cell and a negative cell, respectively. Each of the positive and negative electrode electrolytes contains a vanadium (V) ion as active material. At least one of the positive and negative electrode electrolytes further contains another metal ion, for example, a manganese ion that exhibits a higher redox potential than a V ion or a chromium ion that exhibits a lower redox potential than a V ion. Even in cases where the RF battery is nearly fully charged, side reactions such as generation of oxygen has or hydrogen gas due to water decomposition and oxidation degradation of an electrode can be suppressed since the above-mentioned another metal ion contained together with the V ion is oxidized or reduced in the late stage of charge.

Abstract: A redox flow battery having a high electromotive force and capable of suppressing generation of a precipitation is provided. In a redox flow battery 100, a positive electrode electrolyte and a negative electrode electrolyte are supplied to a battery cell including a positive electrode 104, a negative electrode 105, and a membrane 101 interposed between the electrodes 104 and 105, to charge and discharge the battery. The positive electrode electrolyte contains a manganese ion, or both of a manganese ion and a titanium ion. The negative electrode electrolyte contains at least one type of metal ion selected from a titanium ion, a vanadium ion, a chromium ion, a zinc ion, and a tin ion. The redox flow battery 100 can suppress generation of a precipitation of MnO2, and can be charged and discharged well by containing a titanium ion in the positive electrode electrolyte, or by being operated such that the positive electrode electrolyte has an SOC of not more than 90%.

Abstract: A redox flow (RF) battery performs charge and discharge by supplying a positive electrode electrolyte and a negative electrode electrolyte to a battery cell. Each of the positive electrode electrolyte and the negative electrode electrolyte contains a vanadium (V) ion as active material. At least one of the positive electrode electrolyte and the negative electrode electrolyte further contains another metal ion, for example, a metal ion such as a manganese ion that exhibits a higher redox potential than a V ion or a metal ion such as a chromium ion that exhibits a lower redox potential than a V ion.

Abstract: A redox flow battery having a high electromotive force and capable of suppressing generation of a precipitation is provided. In a redox flow battery 100, a positive electrode electrolyte and a negative electrode electrolyte are supplied to a battery cell including a positive electrode 104, a negative electrode 105, and a membrane 101 interposed between the electrodes 104 and 105, to charge and discharge the battery. The positive electrode electrolyte contains a manganese ion, or both of a manganese ion and a titanium ion. The negative electrode electrolyte contains at least one type of metal ion selected from a titanium ion, a vanadium ion, a chromium ion, a zinc ion, and a tin ion. The redox flow battery 100 can suppress generation of a precipitation of MnO2, and can be charged and discharged well by containing a titanium ion in the positive electrode electrolyte, or by being operated such that the positive electrode electrolyte has an SOC of not more than 90%.

Abstract: The present invention provides a method of designing a redox flow battery system that can prevent system efficiency loss caused by weak generation power or load power at the time of electric charge or discharge, without using any lead storage battery, and can also provide further improved system efficiency. In the present invention, generating equipment that varies irregularly in output of power generation is provided with the redox flow battery to smooth the output of power generation. An average value of output distribution of the battery with respect to the smoothed output of power generation and standard deviation are determined. Then, at least either of a specified output of the battery and a specified output of the converter for converting the battery output is determined based on the standard deviation.

Abstract: This invention provides a cell frame for a redox flow battery that prevents leakage of electrolyte out of the cell frame and also provides a good workability in assembling the redox flow battery. Also, this invention provides a redox flow battery using the cell frame. In the cell frame 30 for the redox flow battery 30 comprising a bipolar plate 21 and a frame 31 fitted around a periphery of the bipolar plate 21, the frame 31 has, on each side thereof, an inner seal and an outer seal to press-contact with a membrane and also seal electrolyte. The frame 31 has, on each side thereof, an inner seal groove 34 and an outer seal groove 35 for placing therein the inner seal and the outer seal, respectively, to prevent the electrolyte from leaking out, and O-rings are placed in the respective seal grooves.

Abstract: This invention provides a cell frame for a redox flow battery that prevents leakage of electrolyte out of the cell frame and also provides a good workability in assembling the redox flow battery. Also, this invention provides a redox flow battery using the cell frame. In the cell frame 30 for the redox flow battery 30 comprising a bipolar plate 21 and a frame 31 fitted around a periphery of the bipolar plate 21, the frame 31 has, on each side thereof, an inner seal and an outer seal to press-contact with a membrane and also seal electrolyte. The frame 31 has, on each side thereof, an inner seal groove 34 and an outer seal groove 35 for placing therein the inner seal and the outer seal, respectively, to prevent the electrolyte from leaking out, and O-rings are placed in the respective seal grooves.

Abstract: An operating method of a redox flow battery system that can provide a stabilized output to a system from a redox flow battery system annexed to a wind power generator, to produce an improved battery efficiency. The redox flow battery system comprises the wind power generator 10, a redox flow battery 30 annexed to the wind power generator, and an AC/DC converter 40 connected to the redox flow battery.

Abstract: An operating method of a redox flow battery system that can provide a stabilized output to a system from a redox flow battery system annexed to a wind power generator, to produce an improved battery efficiency. The redox flow battery system comprises the wind power generator 10, a redox flow battery 30 annexed to the wind power generator, and an AC/DC converter 40 connected to the redox flow battery.

Abstract: This invention provides a cell stack for a redox flow battery that can provide battery efficiencies with high reliability over a long term, without any adhesive bonding between a bipolar plate and electrodes. In the cell stack 1 for the redox flow battery of a cell frame 2, electrodes 3, 4 and a membrane 5 being stacked in layers, the cell frame 2 comprises a frame 2A and a bipolar plate 9 arranged inside of the frame 2A, and the electrodes 3, 4 are put into close contact with the bipolar plate 9 by a clamping force, without being adhesively bonded to the bipolar plate 9. It is preferable that when the electrodes 3, 4 are compressed to a thickness corresponding to a level difference between the frame 2A and the bipolar plate 9, repulsive force of the electrodes is in the range of more than 15 kPa to less than 150 kPa (more than 0.153 kgf/cm2 to less than 1.53 kgf/cm2).