System and method for low-cost redox flow batteries

Abstract

This disclosure provides batteries with long operating time or long lifespan for energy storage applications. In one embodiment, this disclosure provides a perylenediimide molecule that is water-soluble and can be used as an energy storage material. During operation, the perylenediimide molecule is oxidized in the anode chamber, and the electrons released during this oxidation process flow into the cathode chamber, reducing the molecules in the cathode chamber. In many embodiments, the perylenediimide molecule has extremely high compatibility with inexpensive and easily processed polymer materials, thereby enabling a significant reduction in manufacturing costs.

Description

[Technical Field]

[0001] The present invention relates to a generally low-cost redox flow battery, and more specifically to a redox flow battery using a mild aqueous electrolyte and low-cost battery components. [Background technology]

[0002] In redox flow batteries, the electrolyte solution is stored in a tank, pumped through an electrochemical cell, and returned to the tank. The number of cells (cell stack) determines the system's power output (watts), and the size of the tank can determine the energy (watt-hours). This separation of power and energy is an advantage that allows for easy scale-up of flow batteries. Vanadium oxide redox flow batteries use highly acidic electrolyte solutions, such as those containing sulfuric acid. In addition, vanadium itself is extremely corrosive. As a result, the acidic and corrosive solution components of vanadium oxide redox flow batteries may require cell manufacturing components to be made from highly chemical-resistant materials. For example, vanadium redox flow batteries may require fluorinated polymers as components of the flow battery. These special materials can increase manufacturing costs, especially when scaling up flow battery production. There is a strong need for redox flow batteries for long-term storage that are chemically stable, compatible with inexpensive, mass-producible materials, and have a long-life electrolyte solution. For widespread application of redox flow batteries, a new flow battery system compatible with low-cost, mass-producible materials may be needed. [Overview of the project]

[0003] This specification summarizes, and is described in detail below, a redox flow battery that is suitable for low-cost, non-highly chemical-resistant materials as its various components. In many embodiments, the redox flow battery contains a neutral pH aqueous electrolyte solution. In several embodiments, the low-cost, non-highly chemical-resistant materials remain stable for several weeks to several months under the operating conditions of the redox flow battery. This mild electrolyte solution enables the manufacture of flow batteries incorporating non-highly chemical-resistant materials, allowing for scale-up using readily available materials and cost-reduced mass production techniques.

[0004] In many embodiments, the electrolyte solution may contain water-soluble perylenediimide molecules for charge storage applications, and the aqueous solution is compatible with materials not designated as having high chemical resistance (i.e., non-high chemical-resistant materials). In several embodiments, the electrolyte solution may contain water-soluble perylenediimide molecules and water-soluble ferrocene molecules for charge storage applications, and the aqueous solution is compatible with materials not designated as having high chemical resistance. Compatibility is defined as the absence of little to no harmful electrochemical or physical reactions between any component of the cell and the electrolyte solution that would impair the long-term and multi-year lifespan of the device.

[0005] In many embodiments, a redox flow battery comprises a first half-cell containing an anode solution and a second half-cell containing a cathode solution. The anode solution may include (but are not limited to) water-soluble perylenediimide molecules or water-soluble perylenediimide derivatives. The cathode solution may include (but are not limited to) water-soluble ferrocene molecules or water-soluble ferrocene derivatives. In several embodiments, one or more battery components can be made from non-high chemical-resistant materials. Examples of various battery components include (but are not limited to) electrodes, gaskets, flow frames, diodes, membranes, seals, and tubes. Examples of low-cost and non-high chemical-resistant materials include (but are not limited to) plastics, rubber, elastomers, ceramics, glass, metals, metal alloys, membranes, ion exchange membranes, size exclusion membranes, and any combination thereof. In some embodiments, battery components can be made from non-fluorinated polymers. In several embodiments, the non-fluorinated polymer may include (but is not limited to) polyolefins, polyethers, polyketones, polyamides, polyureas, natural rubber, or any combination thereof.

[0006] In many embodiments, non-high chemical-resistant materials are provided that are suitable for the operating conditions of redox flow batteries across various charge states (SOC) in cycle tests and long-term high SOC exposure tests. Examples of suitable non-high chemical-resistant materials include, but are not limited to, ethylene propylene diene monomer rubber (EPDM), polychloroprene (neoprene), polyamide (nylon), polyether ether ketone (PEEK), polyoxymethylene (POM), polyvinyl chloride (PVC), sodium benzenesulfonate (sodium besylate), sodium 4-toluenesulfonate (sodium tosylate), propylene carbonate, sulfolane, acrylonitrile butadiene rubber (BUNA-N), natural latex rubber, polyethylene (PE), polymethyl methacrylate (PMMA), polypropylene (PP), polyurethane (PUR), and EPDM polypropylene matrix elastomer (santoprene). Certain non-highly chemical-resistant materials, such as 316 stainless steel, 6061 aluminum, and polysiloxane rubber (silicone), may be undesirable for use with redox flow batteries in several embodiments.

[0007] In many embodiments, the battery may be a redox flow battery. In some embodiments, the redox flow battery maintains a capacity retention rate of more than 99% for a period of at least two weeks. In some embodiments, the redox flow battery maintains a capacity retention rate of more than 99.9% for a period of at least two weeks.

[0008] In certain embodiments, the components of a flow battery can be manufactured using a variety of processes including, but not limited to, melting, thermoforming, additive manufacturing, 3D printing, and any combination thereof. Examples of thermoforming methods include, but are not limited to, injection molding, blow molding, and extrusion molding. In several embodiments, the components can be manufactured from materials including hydrocarbon plastics, elastomers, and / or rubber. Specific examples include, but are not limited to, polyethylene, polypropylene, polycarbonate, polystyrene, polyoxymethylene, santoprene, EPDM, neoprene, PEEK, POM, PVC, PMMA, polyurethane, nylon, sodium besylate, sodium tosylate, propylene carbonate, sulfolane, BUNA-N, natural latex rubber, latex, natural rubber, and any combination thereof.

[0009] In many embodiments, the reaction vessel (also known as the flow frame) that defines the inside of a half-cell of the battery can be made from at least one non-fluorinated polymer. Examples of non-fluorinated polymers include (but are not limited to) polyethylene, polypropylene, polymethylpentene (PMP), polybutene-1, PVC, polystyrene, PMMA, acrylonitrile butadiene styrene (ABS), nylon, POM, polycarbonate, PEEK, and any combination thereof. In some embodiments, the reaction vessel can be made from a copolymer derived from two or more of the above polymers.

[0010] Diode plates that come into contact with the cathode solution or anode solution within a half-cell can be made from graphite or a polymer composite. In some embodiments, diode plates can be made from a resin-filled graphite composite. In certain embodiments, the polymer of the resin-filled graphite composite may be polyethylene or polypropylene. In some embodiments, the resin-filled graphite composite may be a thermosetting resin containing (but not limited to) a phenolic resin.

[0011] In several embodiments, gaskets that come into contact with the cathode or anode solution within a half-cell can be made from a non-fluorinated elastomer material. In some embodiments, the non-fluorinated elastomer material is a non-high chemical-resistant rubber material that includes (but is not limited to) EPDM, santoprene, neoprene, butadiene-styrene (BUNA-S), BUNA-N, latex, trans-isoprene, silicone, or polyurethane.

[0012] In many embodiments, the redox flow cell may include supply lines and / or tubes positioned outside the half-cells, carrying the anodic solution and cathode solution to the first and second half-cells, respectively. Supply lines in several embodiments can be made from materials not specified as having high chemical resistance. In certain embodiments, supply lines can be made from non-fluorinated elastomer polymers. In various embodiments, supply lines can be made from non-high chemical-resistant rubber materials, including but not limited to EPDM, Santoprene, neoprene, BUNA-S, BUNA-N, latex, trans-isoprene, silicone, or polyurethane. In several embodiments, supply lines can be made from rigid plastics, including but not limited to polyethylene, polypropylene, or polyvinyl chloride.

[0013] In some embodiments, the membrane of a redox flow cell can be made from an ion exchange membrane, including (but not limited to) an anion exchange membrane. In several embodiments, in a redox flow cell, Selemion TM anion exchange membrane or cation exchange membrane, and / or Selemion TM AMVN and / or Selemion TM CMVN film is used. Selemion TM AMVN is a styrene-based anion exchange membrane and may contain various functional groups. TMCMVN is a styrenic cation exchange membrane and may contain various functional groups. In certain embodiments, in a redox flow battery, Fumasep TM FAA-3-20 is used as the anion exchange membrane. In certain embodiments, in a redox flow battery, Fumasep TM FAA-3-50 is used as the anion exchange membrane. In certain embodiments, in a redox flow battery, Fumasep TM FAS-30 is used as the anion exchange membrane. In certain embodiments, in a redox flow battery, Fumasep TM FAM-PP is used as the anion exchange membrane. In certain embodiments, in a redox flow battery, Fumasep TM FAPQ-375-PP is used as the anion exchange membrane. In certain embodiments, in a redox flow battery, Fumasep TM FKS-PK-75 is used as the cation exchange membrane. In certain embodiments, in a redox flow battery, Fumasep TM FKS-50 is used as the cation exchange membrane. In certain embodiments, in a redox flow battery, Fumasep TM E620K is used. Fumasep TM FAA-3-~30, FAA-3-50, FAS-30, FAM-PP, and FAPQ-375-PP are anion exchange membranes. Fumasep TM FKS-PK-75, FKS-50, and E620K are anion exchange membranes. Fumasep TM The membrane is a polyether ether ketone-based membrane and may contain various functional groups.

[0014] In many embodiments, it is provided that the redox flow battery is compatible with functional groups including, but not limited to, small molecules such as sodium besylate, sodium tosylate, propylene carbonate, sulfolane, and any combination thereof.

[0015] In some embodiments, the compound of formula (I) [ka] or containing the salt thereof, T is -(LG) n -X is, T' represents H, (C1-C6) alkyl, or -(LG) n -X is, L is a -(C2-C5)-alkyl group, optionally substituted with OH, OCH3, or halogen. [ka] And, Each X is independently H, -(C1-C 10 ) alkyl, -(C2-C6)alkenyl, -(C2-C6)alkynyl, and -(C1-C6)alkoxy, each of which is unsubstituted or independently selected with 1, 2, or 3 R 1 It is substituted with the base, Each R 1 These are independently -OH, -O(C1-C6)-alkyl, -O(C1-C6)-alkyl-O(C1-C6)-alkyl, -O(C1-C6)-alkyl-O(C1-C6)-alkyl-O(C1-C6)alkyl, -[O(C1-C6)-alkyl] p -O(C1-C6), -O(C=O)(C1-C6)alkyl, -O(C=O)O(C1-C6)alkyl, -O(C=O)OH, -O(C=O)NH2, -O(C=O)NH(C1-C6)alkyl, O(C=O)N[(C1-C6)alkyl]2, -NH(C=O)(C1-C6)alkyl, N(C1-C6)alkyl(C=O)(C1-C6)alkyl, halogen, -CN, -NO2, NH2, NH(C1-C6)alkyl, and N[(C1-C6)alkyl]2. n=2 to 8, p = 3 to 20.

[0016] In some embodiments, T and T' are each independently -(LG) n -X is the case.

[0017] In some embodiments, L is an unsubstituted -(C2-C5)-alkyl group.

[0018] In some embodiments, L is ethyl or propyl.

[0019] In some embodiments, n is 2, 3, or 4.

[0020] In some embodiments, G is [ka] That is the case.

[0021] In some embodiments, X is H, methyl, or -CH2CH2OH.

[0022] In some embodiments, each X is independently H or -(C1-C6)-alkyl.

[0023] In some embodiments, at least one X is -CH2CH2OH.

[0024] In some embodiments, the compound of formula (I) is [ka] [ka] [ka] [ka] [ka] [ka] That is the case.

[0025] In some embodiments, the compound of formula (II) is [ka] Includes, Each Y is independently -O-, -S-, or -NH-. Each q is independently between 1 and 8. Each X is independently H, -(C1-C 10 )-alkyl, -(C2-C6)alkenyl, -(C2-C6)alkynyl, and -(C1-C6)alkoxy, each of which is unsubstituted or independently selected with 1, 2, or 3 R 1 It is substituted with the base, Each R 1 These are independently -OH, -O(C1-C6)-alkyl, -O(C1-C6)-alkyl-O(C1-C6)-alkyl, -O(C1-C6)-alkyl-O(C1-C6)-alkyl-O(C1-C6)alkyl, -[O(C1-C6)-alkyl] p -O(C1-C6), -O(C=O)(C1-C6)alkyl, -O(C=O)O(C1-C6)alkyl, -O(C=O)OH, -O(C=O)NH2, -O(C=O)NH(C1-C6)alkyl, O(C=O)N[(C1-C6)alkyl]2, -NH(C=O)(C1-C6)alkyl, N(C1-C6)alkyl(C=O)(C1-C6)alkyl, halogen, -CN, -NO2, NH2, NH(C1-C6)alkyl, and N[(C1-C6)alkyl]2. Each V is a counterion.

[0026] In some embodiments, the compound of formula (II) is [ka] That is the case.

[0027] In some embodiments, the compound of formula (III) is [ka] Includes, Each X is independently H, -(C1-C 10 )-alkyl, -(C2-C6)alkenyl, -(C2-C6)alkynyl, and -(C1-C6)alkoxy, each of which is unsubstituted or independently selected with 1, 2, or 3 R 1 It is substituted with the base, Each R 1 These are independently -OH, -O(C1-C6)-alkyl, -O(C1-C6)-alkyl-O(C1-C6)-alkyl, -O(C1-C6)-alkyl-O(C1-C6)-alkyl-O(C1-C6)alkyl, -[O(C1-C6)-alkyl] p -O(C1-C6), -O(C=O)(C1-C6)alkyl, -O(C=O)O(C1-C6)alkyl, -O(C=O)OH, -O(C=O)NH2, -O(C=O)NH(C1-C6)alkyl, O(C=O)N[(C1-C6)alkyl]2, -NH(C=O)(C1-C6)alkyl, N(C1-C6)alkyl(C=O)(C1-C6)alkyl, halogen, -CN, -NO2, NH2, NH(C1-C6)alkyl, and N[(C1-C6)alkyl]2. Each s is independently between 2 and 4. Each R is independently H, -CH2OH, -CH2CH2OH, -CH2CH2OCH2CH2OH, or -CH2CH2OCH2CH2O(C1-6)alkyl. Each V - It is a counterion.

[0028] In some embodiments, the compound of formula (III) is [ka] [ka] That is the case.

[0029] In some embodiments, the compound of formula (IV) [ka] Includes, R is [ka] [ka] [ka] That is the case.

[0030] In some embodiments, the compound of formula (IV) is [ka] That is the case.

[0031] In some embodiments, the compound of formula (V) [ka] or containing the salt thereof, L is -(C1-C6)-alkyl, Each G is [ka] And, A is a positive ion, n=1 to 5

[0032] In some embodiments, L is substituted with OH, OCH3, and halogens.

[0033] In some embodiments, each A is lithium, sodium, potassium, or ammonium.

[0034] In some embodiments, each G is [ka] That is the case.

[0035] In some embodiments, each L is propyl.

[0036] In some embodiments, n is 2.

[0037] In some embodiments, LG n The group has at least one chiral center.

[0038] In some embodiments, formula (V) has at least one stereoisomer.

[0039] In some embodiments, the compound of formula (V) is [ka] That is the case.

[0040] In some embodiments, the compound of formula (V) is [ka] That is the case.

[0041] In some embodiments, the compound of formula (V) is [ka] That is the case.

[0042] In some embodiments, the compound of formula (V) is [ka] The group is selected from the group consisting of any combination of these.

[0043] In some embodiments, A is lithium, sodium, potassium, or ammonium.

[0044] In some embodiments, the compound of formula (V) is [ka] That is the case.

[0045] In some embodiments, [ka] , [ka] , [ka] , [ka] , [ka] , [ka] , [ka] , [ka] , [ka] [ka] It includes compounds having a formula selected from the group consisting of the following.

[0046] In some embodiments, the compound of formula (VI) [ka] Includes, L is -(C1-C 10 )-alkyl, -(C1-C6)-alkenyl, -(C1-C6)-alkynyl, -(C1-C6)-alkyl-O(C1-C6)-alkyl, -(C1-C6)-alkyl-O-(C=O)-(C1-C6)alkyl, -(C1-C6)-alkyl-(C=O)-O-(C1-C6)alkyl, -(C1-C6)alkyl-NH-(C=O)(C1-C6)alkyl, -(C1-C6)alkyl-NR 2 -(C=O)(C1-C6)alkyl, -(C1-C6)alkyl-(C=O)-NH-(C1-C6)alkyl, -(C1-C6)alkyl-(C=O)-NR 2 -(C1-C6)alkyl, or -(C1-C 10 It is an alkyl-aryl compound.

[0047] L' is -H, -(C1-C 10 )-alkyl, -(C1-C6)-alkenyl, -(C1-C6)-alkynyl, -(C1-C6)-alkyl-O(C1-C6)-alkyl, -(C1-C6)-alkyl-O-(C=O)-(C1-C6)alkyl, -(C1-C6)-alkyl-(C=O)-O-(C1-C6)alkyl, -(C1-C6)alkyl-NH-(C=O)(C1-C6)alkyl, -(C1-C6)alkyl-NR 2 -(C=O)(C1-C6)alkyl, -(C1-C6)alkyl-(C=O)-NH-(C1-C6)alkyl, -(C1-C6)alkyl-(C=O)-NR 2 -(C1-C6)alkyl, or -(C1-C 10 )-alkyl-aryl, G is [ka] Selected from the group consisting of, G is 2 or greater, A is Li, K, Na, or NH4. R 2 is, -(C1-C 10 )-alkyl, -(C1-C6)-alkenyl, -(C1-C6)-alkynyl, -(C1-C 10 It is an alkyl-aryl, -aryl, or -(C=O)-(C1-C6)-alkyl.

[0048] In some embodiments, L is substituted with at least one group selected from the group consisting of G, -OH, -OCH3, and -halogens.

[0049] In some embodiments, L′ is substituted with at least one group selected from the group consisting of G, -OH, -OCH3, and -halogens.

[0050] In some embodiments, R 2 It is replaced by at least one G.

[0051] In some embodiments, LG n It has at least one chiral center.

[0052] In some embodiments, the compound has at least one stereoisomer.

[0053] In some embodiments, the compound of formula (VI) is [ka] That is the case.

[0054] In some embodiments, the compound of formula (VI) is [ka] That is the case.

[0055] In some embodiments, the compound of formula (VI) is [ka] That is the case.

[0056] In some embodiments, the compound of formula (VI) is [ka] The group is selected from the group consisting of any combination of these.

[0057] In some embodiments, the compound of formula (VI) is [ka] That is the case.

[0058] Some embodiments include a redox flow battery, the redox flow battery comprising: a first half-cell containing a first aqueous solution comprising a first electrode and an anode liquid, the anode liquid comprising a perylenediimide compound; a second half-cell containing a second aqueous solution comprising a second electrode and a cathode liquid; and a separator interposed between the first half-cell and the second half-cell, wherein the inner surface of the first half-cell in contact with the first aqueous solution and the inner surface of the second half-cell in contact with the second aqueous solution comprises one or more non-highly chemical-resistant materials.

[0059] In some embodiments, the non-highly chemical-resistant material is a polymer.

[0060] In some embodiments, the polymer is a non-fluorinated polymer.

[0061] In some embodiments, the non-fluorinated polymer is selected from the group consisting of polyolefins, polyethers, polyketones, polyamides, polyureas, natural rubber, and combinations thereof.

[0062] In some embodiments, the non-fluorinated polymer is a copolymer of two or more polymers selected from the group consisting of polyolefins, polyethers, polyketones, polyamides, polyureas, and natural rubber.

[0063] In some embodiments, the non-fluorinated polymer is selected from the group consisting of ethylene propylene diene monomer rubber (EPDM), polychloroprene (neoprene), polyamide (nylon), polyether ether ketone (PEEK), polyoxymethylene (POM), polyvinyl chloride (PVC), sodium benzenesulfonate (sodium besylate), sodium 4-toluenesulfonate (sodium tosylate), propylene carbonate, sulfolane, acrylonitrile butadiene rubber (BUNA-N), natural latex rubber, polyethylene (PE), polymethyl methacrylate (PMMA), polypropylene (PP), polyurethane (PUR), EPDM polypropylene matrix elastomer (santoprene), and combinations thereof.

[0064] In some embodiments, the non-fluorinated polymer is a copolymer of two or more polymers selected from the group consisting of ethylene propylene diene monomer rubber (EPDM), polychloroprene (neoprene), polyamide (nylon), polyether ether ketone (PEEK), polyoxymethylene (POM), polyvinyl chloride (PVC), sodium benzenesulfonate (sodium besylate), sodium 4-toluenesulfonate (sodium tosylate), propylene carbonate, sulfolane, acrylonitrile butadiene rubber (BUNA-N), natural latex rubber, polyethylene (PE), polymethyl methacrylate (PMMA), polypropylene (PP), polyurethane (PUR), and EPDM polypropylene matrix elastomer (santoprene).

[0065] In some embodiments, the first half-cell includes a first diode plate, the second half-cell includes a second diode plate, and the first diode plate includes a composite material of graphite and polymer.

[0066] In some embodiments, the composite material is resin-filled graphite.

[0067] In some embodiments, the first electrode plate material comprises graphite in a thermosetting resin matrix.

[0068] In some embodiments, the polymer of the composite material is polyethylene or polypropylene.

[0069] In some embodiments, the system further includes a gasket separating the reaction vessel from the first electrode plate, the gasket comprising a non-highly chemical-resistant elastomer material.

[0070] In some embodiments, the non-high chemical-resistant elastomer material is a non-fluorinated elastomer material.

[0071] In some embodiments, non-highly chemical-resistant elastomer materials are selected from the group consisting of ethylene propylene diene monomer rubber (EPDM), polychloroprene (neoprene), polyamide (nylon), polyether ether ketone (PEEK), polyoxymethylene (POM), polyvinyl chloride (PVC), sodium benzenesulfonate (sodium besylate), sodium 4-toluenesulfonate (sodium tosylate), propylene carbonate, sulfolane, acrylonitrile butadiene rubber (BUNA-N), natural latex rubber, polyethylene (PE), polymethyl methacrylate (PMMA), polypropylene (PP), polyurethane (PUR), EPDM polypropylene matrix elastomer (santoprene), and combinations thereof.

[0072] In some embodiments, the separator includes an ion exchange membrane.

[0073] In some embodiments, the ion exchange membrane includes a non-fluorinated polymer.

[0074] In some embodiments, the ion exchange membrane is a polystyrene-based ion exchange membrane.

[0075] In some embodiments, the system further includes a supply line positioned outside the first half-cell to supply an anodic acid to the first half-cell, the supply line comprising a non-highly chemical-resistant elastomer material.

[0076] In some embodiments, the non-high chemical-resistant elastomer material is a non-fluorinated elastomer polymer.

[0077] In some embodiments, non-highly chemical-resistant elastomer materials are selected from the group consisting of ethylene propylene diene monomer rubber (EPDM), polychloroprene (neoprene), polyamide (nylon), polyether ether ketone (PEEK), polyoxymethylene (POM), polyvinyl chloride (PVC), sodium benzenesulfonate (sodium besylate), sodium 4-toluenesulfonate (sodium tosylate), propylene carbonate, sulfolane, acrylonitrile butadiene rubber (BUNA-N), natural latex rubber, polyethylene (PE), polymethyl methacrylate (PMMA), polypropylene (PP), polyurethane (PUR), EPDM polypropylene matrix elastomer (santoprene), and combinations thereof.

[0078] In some embodiments, the perylenediimide compound is of formula (I) [ka] or having a salt thereof, T is -(LG) n -X is, T' is H, C1-6 alkyl, or -(LG) n -X is, L is a -(C2-C5)-alkyl group, optionally substituted with OH, OCH3, or halogen. [ka] And, Each X is independently H, -(C1-C 10 ) alkyl, -(C2-C6)alkenyl, -(C2-C6)alkynyl, and -(C1-C6)alkoxy, each of which is unsubstituted or independently selected with 1, 2, or 3 R 1 It is substituted with the base, Each R 1 These are independently -OH, -O(C1-C6)-alkyl, -O(C1-C6)-alkyl-O(C1-C6)-alkyl, -O(C1-C6)-alkyl-O(C1-C6)-alkyl-O(C1-C6)alkyl, -[O(C1-C6)-alkyl] p -O(C1-C6), -O(C=O)(C1-C6)alkyl, -O(C=O)O(C1-C6)alkyl, -O(C=O)OH, -O(C=O)NH2, -O(C=O)NH(C1-C6)alkyl, O(C=O)N[(C1-C6)alkyl]2, -NH(C=O)(C1-C6)alkyl, N(C1-C6)alkyl(C=O)(C1-C6)alkyl, halogen, -CN, -NO2, NH2, NH(C1-C6)alkyl, and N[(C1-C6)alkyl]2. n=2 to 8, p = 3 to 20.

[0079] In some embodiments, the perylenediimide compound is of formula (II) [ka] It has, Each Y is independently -O-, -S-, or -NH-. Each q is independently between 1 and 8. Each X is independently H, -(C1-C 10 )-alkyl, -(C2-C6)alkenyl, -(C2-C6)alkynyl, and -(C1-C6)alkoxy, each of which is unsubstituted or independently selected with 1, 2, or 3 R 1 It is substituted with the base, Each R 1These are independently -OH, -O(C1-C6)-alkyl, -O(C1-C6)-alkyl-O(C1-C6)-alkyl, -O(C1-C6)-alkyl-O(C1-C6)-alkyl-O(C1-C6)alkyl, -[O(C1-C6)-alkyl] p -O(C1-C6), -O(C=O)(C1-C6)alkyl, -O(C=O)O(C1-C6)alkyl, -O(C=O)OH, -O(C=O)NH2, -O(C=O)NH(C1-C6)alkyl, O(C=O)N[(C1-C6)alkyl]2, -NH(C=O)(C1-C6)alkyl, N(C1-C6)alkyl(C=O)(C1-C6)alkyl, halogen, -CN, -NO2, NH2, NH(C1-C6)alkyl, and N[(C1-C6)alkyl]2. Each V is a counterion.

[0080] In some embodiments, the perylenediimide compound is of formula (III) [ka] It has, Each X is independently H, -(C1-C 10 )-alkyl, -(C2-C6)alkenyl, -(C2-C6)alkynyl, and -(C1-C6)alkoxy, each of which is unsubstituted or independently selected with 1, 2, or 3 R 1 It is substituted with the base, Each R 1 These are independently -OH, -O(C1-C6)-alkyl, -O(C1-C6)-alkyl-O(C1-C6)-alkyl, -O(C1-C6)-alkyl-O(C1-C6)-alkyl-O(C1-C6)alkyl, -[O(C1-C6)-alkyl] p-O(C1-C6), -O(C=O)(C1-C6)alkyl, -O(C=O)O(C1-C6)alkyl, -O(C=O)OH, -O(C=O)NH2, -O(C=O)NH(C1-C6)alkyl, O(C=O)N[(C1-C6)alkyl]2, -NH(C=O)(C1-C6)alkyl, N(C1-C6)alkyl(C=O)(C1-C6)alkyl, halogen, -CN, -NO2, NH2, NH(C1-C6)alkyl, and N[(C1-C6)alkyl]2. Each s is independently between 2 and 4. Each R is independently H, -CH2OH, -CH2CH2OH, -CH2CH2OCH2CH2OH, or -CH2CH2OCH2CH2O(C1-6)alkyl. Each V - It is a counterion.

[0081] In some embodiments, the perylenediimide compound is of formula (IV) [ka] It has, R is [ka] , [ka] [ka] That is the case.

[0082] In some embodiments, the perylenediimide compound is of formula (V) [ka] or having a salt thereof, L is -(C1-C6)-alkyl, Each G is [ka] And, A is a positive ion, n=1 to 5

[0083] In some embodiments, the cathode liquid contains a ferrocene compound.

[0084] In some embodiments, the ferrocene compound is [ka] , [ka] , [ka] [ka] , [ka] [ka] , [ka] , [ka] , [ka] [ka] It has an expression selected from the group consisting of the following.

[0085] In some embodiments, the ferrocene compound is of formula (VI) [ka] It has, L is -(C1-C 10 )-alkyl, -(C1-C6)-alkenyl, -(C1-C6)-alkynyl, -(C1-C6)-alkyl-O(C1-C6)-alkyl, -(C1-C6)-alkyl-O-(C=O)-(C1-C6)alkyl, -(C1-C6)-alkyl-(C=O)-O-(C1-C6)alkyl, -(C1-C6)alkyl-NH-(C=O)(C1-C6)alkyl, -(C1-C6)alkyl-NR 2 -(C=O)(C1-C6)alkyl, -(C1-C6)alkyl-(C=O)-NH-(C1-C6)alkyl, -(C1-C6)alkyl-(C=O)-NR 2 -(C1-C6)alkyl, or -(C1-C 10 )-alkyl-aryl, L' is -H, -(C1-C 10 )-alkyl, -(C1-C6)-alkenyl, -(C1-C6)-alkynyl, -(C1-C6)-alkyl-O(C1-C6)-alkyl, -(C1-C6)-alkyl-O-(C=O)-(C1-C6)alkyl, -(C1-C6)-alkyl-(C=O)-O-(C1-C6)alkyl, -(C1-C6)alkyl-NH-(C=O)(C1-C6)alkyl, -(C1-C6)alkyl-NR 2 -(C=O)(C1-C6)alkyl, -(C1-C6)alkyl-(C=O)-NH-(C1-C6)alkyl, -(C1-C6)alkyl-(C=O)-NR 2 -(C1-C6)alkyl, or -(C1-C 10 )-alkyl-aryl, G is [ka] Selected from the group consisting of, G is 2 or greater, A is Li, K, Na, or NH4. R 2 is, -(C1-C 10 )-alkyl, -(C1-C6)-alkenyl, -(C1-C6)-alkynyl, -(C1-C 10 It is an alkyl-aryl, -aryl, or -(C=O)-(C1-C6)-alkyl.

[0086] Additional embodiments and configurations are described in part in the following description and will become apparent to those skilled in the art by a close examination of this specification or will be understood by carrying out the subject matter of the disclosed invention. A further understanding of the nature and advantages of this disclosure can be obtained by referring to the remainder of this specification and the drawings that constitute parts of this disclosure. [Brief explanation of the drawing]

[0087] [Figure 1] This document shows a redox flow battery using components made from low-cost materials, according to one embodiment of the present invention. [Figure 2] This shows a prototype of a redox flow battery according to one embodiment of the present invention. [Figure 3A] The components of an H-cell according to one embodiment of the present invention are shown. [Figure 3B] An assembled H-cell according to one embodiment of the present invention is shown. [Figure 4A] The capacity of an H-cell cycle test using nylon according to one embodiment of the present invention is shown. [Figure 4B] This shows the capacity of an H-cell cycle test using 316 stainless steel according to one embodiment of the present invention. [Figure 5] This is a schematic diagram of the H-cell cycle process using one embodiment of the present invention. [Figure 6A] The HPLC results of EPDM in a high-charge state exposure test according to one embodiment of the present invention are shown. [Figure 6B] The HPLC results of EPDM in a high-charge state exposure test according to one embodiment of the present invention are shown. [Figure 6C]The HPLC results of EPDM in a high-charge state exposure test according to one embodiment of the present invention are shown. [Figure 7] The Coulomb efficiency of a 10mAh flow cell according to one embodiment of the present invention is shown. [Figure 8A] This shows the capacity retention rate after a 14-day cycle of a redox flow battery manufactured using a polypropylene flow frame in contact with an electrolyte solution, according to one embodiment of the present invention. [Figure 8B] This shows the Coulomb efficiency after a 14-day cycle of a redox flow battery manufactured using a polypropylene flow frame in contact with an electrolyte solution, according to one embodiment of the present invention. [Figure 9] The cycle of glutamate-PDI and bis-propylsulfonate ferrocene according to one embodiment of the present invention is shown. [Figure 10] The cycle of glutamate-PDI and glutamate amide ferrocene according to one embodiment of the present invention is shown. [Modes for carrying out the invention]

[0088] The following figures will provide a more comprehensive understanding of the contents of this specification. These figures are presented as illustrative embodiments of the present invention and should not be construed as a complete enumeration of the scope of the invention.

[0089] Here, with reference to the drawings, a redox flow battery comprising low-cost, non-highly chemical-resistant components and a mild electrolyte solution is described.

[0090] Vanadium redox flow batteries are robust systems due to the long lifespan of their electrolytes. However, their high system cost limits their commercialization and widespread adoption. This cost is primarily due to the cell components and the extremely high corrosiveness of vanadium-based compositions. Conventional vanadium redox flow batteries use V 2+ / V 3+ and VO 2+ / VO 2+Ions are dissolved in a sulfuric acid aqueous solution with a pH of less than 1 (H + , HSO4 - , SO4 2- ions), containing a highly oxidizing electrolyte. Due to the extremely acidic and corrosive environment of the vanadium redox flow battery, it is necessary to fluorinate the polymer main chain to impart high chemical resistance. This is because the bond energy of the C-F bond is higher compared to the C-H bond. Fluorinated materials are very expensive when used in the components of the device because their synthesis is complex, the material cost is high, and manufacturing is difficult. For example, polytetrafluoroethylene (PTFE), also known as Teflon (registered trademark), needs to be formed into parts by compression molding and machining using special processing techniques because the polymer does not melt or flow.

[0091] In conventional vanadium redox flow batteries, fluorinated elastomers such as PTFE as a soft material, isostatic pressing graphite as a bipolar plate, fluorinated Nafion membrane as an ion exchange membrane, and fluorinated rubber for cell manufacturing may be required. These materials are generally difficult to manufacture and time-consuming due to their low manufacturability and properties such as not having the melting point required for injection molding or thermoforming. By replacing these highly chemically resistant materials with cheaper and easier-to-manufacture plastics and rubbers, the scalable structure that separates power and energy can be maximally utilized, and the ability to manufacture cells with high throughput can be significantly improved. In an attempt to replace the vanadium-based pyrolytic and highly resistant graphite bipolar plate with a plastic-filled composite, rapid deterioration of the parts and a decrease in battery performance were confirmed. (For example, Liu, H.; et al., Corrosion behavior of a bipolar plate of carbon-polyethylene composite in a vanadium redox flow battery. RSC Advances 2015, 5 (8), 5928-5932, this disclosure is incorporated herein by reference.)

[0092] The organic molecules used as charge carriers allow for the use of various organic solvents and / or aqueous solutions under non-corrosive, near-neutral pH conditions. However, organic redox flow batteries do not exhibit long-term molecular stability because the organic radicals generated when charge is stored in the organic molecules are extremely unstable. The instability of most organic radicals is also reflected in the short lifespan of organic redox flow batteries, due to chemical events that consume, eliminate, or decompose active substances in the electrolyte. These chemical events include, but are not limited to, reactions between neutral or active charge carrier species and materials used to construct the device itself. In addition, degradation of cell manufacturing materials through contact with the electrolyte composition can alter the mechanical and chemical properties of the materials, potentially shortening the lifespan by causing brittleness, leakage, or other undesirable performance. The radical species generated in organic redox flow batteries are highly reactive radical reducing and oxidizing agents and can react with many functional groups present in cheaper, less chemically resistant materials, including olefins, esters, CH bonds, and / or amides. Conventional vanadium redox flow batteries are assembled from the following: 1) Fluorinated polymers, PTFE (Teflon®), PVDF (Viton), Nafion, Karles®, and other highly chemical-resistant materials (but not limited to these); 2) Non-reactive minerals such as glass, graphite, and carbon felt (but not limited to these); 3) Other resistant materials and any coatings to enhance chemical resistance; 4) Chemical-resistant separators such as fluorinated films.

[0093] In many embodiments, electrolyte compositions containing stable radicals for redox flow batteries are provided. Stable radicals from electrolyte compositions according to several embodiments may not cause oxidation or reduction reactions with cell manufacturing materials. In some embodiments, the electrolyte composition can be dissolved in an aqueous solution of neutral pH (pH from about 5.5 to about 8.5), thereby enabling inexpensive plastics and natural and synthetic rubbers to be easily melted, injection molded, and processed in high-throughput devices. In several embodiments, the cost of cell manufacturing can be reduced by eliminating corrosive solvents and reactive radical species. Polyolefin plastics such as polypropylene and polyethylene can be synthesized from natural gas and petroleum. In many embodiments, by using non-highly chemical-resistant materials for various components of the battery system, the manufacturing cost and raw material cost can be reduced, and the cost of the redox flow battery can be decreased.

[0094] In many embodiments, long-duration operation and / or long-life redox flow batteries for energy storage applications are provided. In several embodiments, water-soluble perylene diimide molecules or perylene diimide-based molecules can be used as energy storage materials. During operation, molecules containing a neutral perylene diimide backbone in the anode chamber (cell) can be reduced during charging to store energy, and then the reduced form can be oxidized during discharging to release energy. Similarly, in the cathode chamber, electrons can be released from the charge storage material during the charging oxidation process to store energy, and then the charge storage material can be reduced during discharging to release energy. In several embodiments, ferrocene or ferrocene-based molecules are implemented as the cathode charge storage material. In many embodiments, perylene diimide molecules, perylene diimide-based molecules, ferrocene molecules, and ferrocene-based molecules are compatible with inexpensive and easily processed polymer materials, thus reducing the manufacturing cost of the redox flow battery.

[0095] In many embodiments, the anodic solution can contain water-soluble perylenediimide (PDI) molecules. The highly conjugated, electron-deficient skeleton of PDI is readily and reversibly reduced to accept two electrons. In several embodiments, perylenediimides having functional groups on one or both of the imide nitrogen atoms can be synthesized from perylenetetracarboxylic dianhydride (PD / 1) by condensation with a primary amine. Organic, water-soluble, polymeric, and liquid crystalline perylenediimides have been developed, and the properties of perylenediimides can be modified by selecting functional groups bonded to one or both of the nitrogen atoms. We have found that while these molecular modifications can alter specific properties of perylenediimides, they do not significantly affect the charge storage stability of perylenediimides. The electron and frontier molecular orbital densities of the perylenediimide skeleton are concentrated in the aromatic main chain, meaning that the redox properties of N-functionalized perylenediimides can be identical in energy level, reversibility, and stability in solution, with or without modification. Consequently, such molecular modifications do not affect charge storage stability.

[0096] In several embodiments, the perylenediimide molecule used as the anode liquid may contain a perylenediimide redox skeleton covalently bonded to a solubilizing group. In certain embodiments, the perylenediimide skeleton can be solubilized by the addition of an ionic scaffold. Any common ionic group, including but not limited to ammonium ions, carboxylates, phosphonates, sulfonates, imidizolium, pyridinium, and thiazolium, can be used to solubilize the perylenediimide skeleton. In various embodiments, one or both nitrogen atoms of the perylenediimide skeleton may be covalently bonded to a quaternated aminoalkyl group. In some embodiments, one or both nitrogen atoms of the perylenediimide skeleton may be covalently bonded to a carboxylate group.

[0097] In many embodiments, perylenediimide molecules can exhibit high stability in both charged and / or uncharged states. Perylenediimide in several embodiments exhibits stability in a two-electron reduced state when present at high concentrations in an aqueous medium. In some embodiments, perylenediimide molecules are compatible with both ion exchange membranes and size exclusion membranes.

[0098] In many embodiments, the perylenediimide molecule is provided to be water-soluble. In certain embodiments, the anolyte solution may contain a perylenediimide compound dissolved in water without the use of additional solvents. The perylenediimide compound can be dissolved in water, tap water, groundwater, well water, filtered water, or deionized water (but not limited to these). For ease of understanding, various water sources can be used as appropriate depending on the requirements of the specific application according to various embodiments of the present invention. Before use, filtration can be performed to filter out unwanted components. For ease of understanding, various filtered waters and / or various water filtration processes can be used as appropriate depending on the requirements of the specific application according to various embodiments of the present invention. In some embodiments, the anolyte solution may contain a supporting electrolyte including (but not limited to) NaCl, KCl, NH4Cl, Na2SO4, MgCl2, or mixtures thereof. In certain embodiments, the anolyte solution may contain a co-solvent to increase the solubility of the perylenediimide compound in aqueous solution. Examples of co-solvents include (but not limited to) methanol, propylene carbonate, and ethylene glycol.

[0099] Perylenediimide molecules according to several embodiments may be chemically stable under various pH conditions. In some embodiments, the anodic solution can be prepared in an acidic, neutral, or basic aqueous medium. In several embodiments, the anodic solution can be prepared at a neutral pH (pH about 7) or at a pH of about 6 to about 8, and further at a pH of about 6.5 to about 7.5. In several embodiments, the anodic solution is prepared in a basic medium. In these embodiments, the pH of the anodic solution can vary in the range of about 7.5 to about 10. In several embodiments, the anodic solution is prepared in an acidic medium, and the pH of the anodic solution is in the range of about 4 to about 6.5, or about 5 to about 6.5.

[0100] In many embodiments, the cathode solution can be prepared in an acidic, neutral, or basic medium. In several embodiments, the cathode solution can be prepared at a neutral pH (pH about 7), or at a pH of about 6 to about 8, and further at a pH of about 6.5 to about 7.5. In some embodiments, the cathode solution is prepared in a basic medium, and the pH of the cathode solution is in the range of about 7.5 to about 10. In several embodiments, the cathode solution can be prepared in an acidic medium, and the pH of the cathode solution is in the range of about 4 to about 6.5, or about 5 to about 6.5.

[0101] In some embodiments, the pH of both the anode solution and the cathode solution can be set to a neutral or near-neutral value (in the range of approximately 5.5 to 8.5). In several embodiments, the anode solution and the cathode solution can be prepared using tap water.

[0102] In various embodiments, the perylenediimide compound has the structure of formula (I). [ka] or it may have a salt thereof T is -(LG) n -X is, T' is H, C 1-6 Alkyl, or -(LG) n -X is, L is a -(C2-C5)-alkyl group, optionally substituted with OH, OCH3, or halogen. [ka] And, Each X is independently H, -(C1-C 10 ) alkyl, -(C2-C6)alkenyl, -(C2-C6)alkynyl, and -(C1-C6)alkoxy, each of which is unsubstituted or independently selected with 1, 2, or 3 R 1 It is substituted with the base, Each R 1 These are independently -OH, -O(C1-C6)-alkyl, -O(C1-C6)-alkyl-O(C1-C6)-alkyl, -O(C1-C6)-alkyl-O(C1-C6)-alkyl-O(C1-C6)alkyl, -[O(C1-C6)-alkyl] p -O(C1-C6), -O(C=O)(C1-C6)alkyl, -O(C=O)O(C1-C6)alkyl, -O(C=O)OH, -O(C=O)NH2, -O(C=O)NH(C1-C6)alkyl, O(C=O)N[(C1-C6)alkyl]2, -NH(C=O)(C1-C6)alkyl, N(C1-C6)alkyl(C=O)(C1-C6)alkyl, halogen, -CN, -NO2, NH2, NH(C1-C6)alkyl, and N[(C1-C6)alkyl]2. n=2 to 8, p = 3 to 20.

[0103] In the compound of formula (I), each LG group of variable T may be the same or different. In some embodiments, when n is 2, each L may be ethyl. In certain embodiments, the first L group may be ethyl and the second L group may be propyl. According to some embodiments, the G groups of variable T may be the same or different. In some embodiments, when n is 2, each G group of LG may be an ammonium group. In some embodiments, the first G group may be an ammonium group and the second G group may be a pyridinium group.

[0104] In some embodiments, the perylene diimide molecule of formula (I) may be such that the perylene diimide compound is symmetric (i.e., T = T′). In certain embodiments, the perylene diimide compound is asymmetric (i.e., T and T′ are not equivalent).

[0105] In several embodiments, in the perylene diimide molecule of formula (I), each L of L-G is ethyl or propyl.

[0106] In some embodiments, the perylene diimide molecule may be a compound in which n is 2 in formula (I). In several embodiments, the perylene diimide molecule may be a compound in which n is 3 in formula (I). In certain embodiments, the perylene diimide molecule may be a compound in which n is 4 in formula (I).

[0107] In many embodiments, in the perylene diimide molecule of formula (I), L may be -(C2-C5)-alkyl without substituents. In certain embodiments, L may be ethyl without substituents. In some embodiments, L may be propyl without substituents.

[0108] In some embodiments, in the perylene diimide molecule of formula (I), G is

Chemical formula

[0109] In some embodiments, in the perylene diimide molecule of formula (I), each X may be independently H or -(C1-C6)-alkyl.

[0110] In several embodiments, in the perylenediimide molecule of formula (I), at least one X may be -(C1-C6)-alkyl-OH. In some embodiments, at least one X may be -CH3CH2OH.

[0111] In many embodiments, the compound of formula (I) has the following structure. [ka]

[0112] In certain embodiments, the compound of formula (I) has the following structure. [ka]

[0113] In some embodiments, the compound of formula (I) has the following structure. [ka]

[0114] In several embodiments, the compound of formula (I) has the following structure. [ka]

[0115] In many embodiments, the compound of formula (I) has the following structure. [ka]

[0116] In some embodiments, the compound of formula (I) has the following structure. [ka]

[0117] In several embodiments, the perylenediimide compound has the structure of formula (II). [Chemical formula] having each Y is independently -O-, -S- or -NH-; each q is independently from 1 to 8; each X is independently H, -(C1-C 10 )-alkyl, -(C2-C6)alkenyl, -(C2-C6)alkynyl, and -(C1-C6)alkoxy, each of which has no substituent or is substituted with 1, 2 or 3 R 1 groups selected independently; each R 1 is independently -OH, -O(C1-C6)-alkyl, -O(C1-C6)-alkyl-O(C1-C6)-alkyl, -O(C1-C6)-alkyl-O(C1-C6)-alkyl-O(C1-C6)alkyl, -[O(C1-C6)-alkyl] p -O(C1-C6), -O(C=O)(C1-C6)alkyl, -O(C=O)O(C1-C6)alkyl, -O(C=O)OH, -O(C=O)NH2, -O(C=O)NH(C1-C6)alkyl, O(C=O)N[(C1-C6)alkyl]2, -NH(C=O)(C1-C6)alkyl, N(C1-C6)alkyl(C=O)(C1-C6)alkyl, halogen, -CN, -NO2, NH2, NH(C1-C6)alkyl, and N[(C1-C6)alkyl]2; each V is a counter ion.

[0118] In some embodiments, the compound of formula (II) has the following structure.

化

[0119] In various embodiments, the perylene diimide compound has the structure of formula (III)

化

[0120] In several embodiments, the compound of formula (III) has the following structure. [ka]

[0121] In some embodiments, the compound of formula (III) has the following structure. [ka]

[0122] In certain embodiments, the perylenediimide compound has the structure of formula (IV). [ka]

[0123] In some embodiments, the compound of formula (IV) has the following structure. [ka]

[0124] In some embodiments, the perylenediimide compound has the structure of formula (V). [ka] or having a salt thereof, Each L is independently a -(C1-C6)-alkyl group, optionally substituted with OH, OCH3, and halogens. Each G is independent [ka] Selected from, A is a positive ion, n=1 to 5

[0125] In certain embodiments, in formula (V), A may be lithium, sodium, potassium, or ammonium.

[0126] In some embodiments, in formula (V), G is [ka] It is possible.

[0127] In several embodiments, L in formula (V) may be propyl.

[0128] In certain embodiments, n may be 2 in equation (V).

[0129] In a particular embodiment, LG n The group may have one or more chiral centers. In this case, the compound obtained from formula (V) may have several stereoisomers. In some embodiments, the compound may be a single stereoisomer. In other embodiments, the compound may be a mixture of two or more stereoisomers in any ratio. The mixture may contain all stereoisomers of the compound, or it may exclude one or more stereoisomers. If chirality is not shown for the stereocenter, the compound may consist of a mixture of any stereoisomers.

[0130] In many embodiments, the compound of formula (V) is [ka] It is possible.

[0131] In certain embodiments, the compound of formula (V) is [ka] It is possible.

[0132] In certain embodiments, the compound of formula (V) is [ka] It is possible.

[0133] In certain embodiments, the compound of formula (V) has the following stereoisomers [ka] It can be any mixture of the following.

[0134] In certain embodiments, the compound of formula (V) is [ka] It is possible.

[0135] Many embodiments of redox flow batteries may include a cathode solution in the cathode chamber. In some embodiments, the cathode solution contains water-soluble redox-active organic molecules. In certain embodiments, the redox-active component of the cathode may include (but are not limited to) TEMPO, ferrocyanides, iodine, or other cathode materials.

[0136] In some embodiments, the redox active component of the cathode solution is a water-soluble ferrocene compound. In certain embodiments, the ferrocene skeleton can be solubilized by the addition of an ionic scaffold. In several embodiments, the scaffold may contain an ammonium ion. In several embodiments, the scaffold may contain a carboxylate ion. In some embodiments, the scaffold may contain a sulfonate ion. The ferrocene skeleton can be solubilized using any common ionic group, including but not limited to carboxylates, phosphonates, sulfonates, imidizolium, pyridinium, and thiazolium.

[0137] In various embodiments, the ferrocene molecule has one of the following structures. [ka] [ka] [ka] [ka] [ka] [Chemistry] [Chemistry] [Chemistry] [Chemistry] [Chemistry]

[0138] In some embodiments, the ferrocene compound has the structure of formula (VI) [Chemistry] and L is -(C1-C 10 )-alkyl, -(C1-C6)-alkenyl, -(C1-C6)-alkynyl, -(C1-C6)-alkyl-O(C1-C6)-alkyl, -(C1-C6)-alkyl-O-(C=O)-(C1-C6)alkyl, -(C1-C6)-alkyl-(C=O)-O-(C1-C6)alkyl, -(C1-C6)-alkyl-NH-(C=O)(C1-C6)alkyl, -(C1-C6)alkyl-NR 2 -(C=O)(C1-C6)alkyl, -(C1-C6)-alkyl-(C=O)-NH-(C1-C6)alkyl, -(C1-C6)-alkyl-(C=O)-NR 2 -(C1-C6)alkyl, -(C1-C 10 )-alkyl-aryl, each optionally substituted with one or more G, -OH, -OCH3, -halogen, L' is -H, -(C1-C 10)-alkyl, -(C1-C6)-alkenyl, -(C1-C6)-alkynyl, -(C1-C6)-alkyl-O(C1-C6)-alkyl, -(C1-C6)-alkyl-O-(C=O)-(C1-C6)alkyl, -(C1-C6)-alkyl-(C=O)-O-(C1-C6)alkyl, -(C1-C6)alkyl-NH-(C=O)(C1-C6)alkyl, -(C1-C6)alkyl-NR 2 -(C=O)(C1-C6)alkyl, -(C1-C6)alkyl-(C=O)-NH-(C1-C6)alkyl, -(C1-C6)alkyl-(C=O)-NR 2 -(C1-C6)alkyl, -(C1-C 10 )-alkyl-aryl, each optionally substituted with one or more G, -OH, -OCH3, or -halogenates, Each G is independent [ka] You may choose from the following: The number of Gs is 2 or more. A is Li, K, Na, or NH4. R 2 is, -(C1-C 10 )-alkyl, -(C1-C6)-alkenyl, -(C1-C6)-alkynyl, -(C1-C 10 The elements are -alkyl-aryl, -aryl, or -(C=O)-(C1-C6)-alkyl, and may be optionally substituted with one or more Gs.

[0139] In a particular embodiment, LG n The group may have one or more chiral centers. In this case, the compound obtained from formula (VI) may have several stereoisomers. In some embodiments, the compound may be a single stereoisomer. In other embodiments, the compound may be a mixture of two or more stereoisomers in any ratio. The mixture may contain all stereoisomers of the compound, or it may exclude one or more stereoisomers. If chirality is not shown at the stereocenter, the compound may consist of a mixture of any stereoisomers.

[0140] In certain embodiments, the compound of formula (VI) is [ka] It is possible.

[0141] In certain embodiments, the compound of formula (VI) is [ka] It is possible.

[0142] In certain embodiments, the compound of formula (VI) is [ka] It is possible.

[0143] In certain embodiments, the compound of formula (VI) has the following stereoisomers [ka] It can be any mixture of the following.

[0144] In certain embodiments, the compound of formula (VI) is [ka] It is possible.

[0145] In certain embodiments, the anolyte solution and / or the cathode solution may contain a supporting electrolyte. In some embodiments, the supporting electrolyte may not be essential to the anolyte solution and / or the cathode solution. Any supporting electrolyte, including but not limited to inorganic and organic salts, can be used. Typical inorganic salts include, but are not limited to, NaCl, KCl, LiCl, NaBr, KBr, LiBr, NaI, KI, LiI, MgCl2, CaCl2, MgBr2, CaBr2, MgI2, and CaI2, NH4Cl, NH4Br, and NH4I. Typical organic salts include, but are not limited to, alkylammonium chloride, alkylammonium bromide, alkylammonium iodide, sodium tosylate, and sodium besylate. In some embodiments, the solution may also contain, but are not limited to, a cosolvent including sulfolane or propylene carbonate.

[0146] In many embodiments, a redox flow battery is provided comprising the anode solution and cathode solution described above. The anode solution and cathode solution can be pumped through a tube into a half-cell, where they undergo an electrochemical reaction. The anode solution and cathode solution can undergo repeated charge-discharge cycles within the half-cell. The materials used in the manufacture of the battery must be compatible with the anode solution and cathode solution to ensure a long battery life. Redox flow batteries manufactured from common materials according to several embodiments can be manufactured at low cost without compromising battery life. In certain embodiments, the materials can be manufactured using techniques including, but not limited to, melt processing, thermoforming, injection molding, blow molding, extrusion, additive manufacturing, or 3D printing. In several embodiments, the materials used in the manufacture of the battery include non-fluorinated polymers specified to be non-highly chemical resistant. In some embodiments, the materials used in the manufacture of the battery can be made from widely available hydrocarbon plastics and rubbers. In several embodiments, the materials used in the manufacture of the battery may be polyethers (e.g., PEEK or POM), polynitriles (e.g., ABS or BUNA-N), polyolefins (e.g., EPDM or Santoprene rubber or neoprene rubber) or latex or ABS, polyhalides (e.g., PVC), polyureas (e.g., polyurethane), polycarbonates (e.g., polycarbonate), amides (e.g., nylon), and polyaromatic materials (e.g., polystyrene or BUNA-S).

[0147] In some embodiments, at least one of the materials used to manufacture the battery is polyethylene. In several embodiments, at least one of the materials used to manufacture the battery is polypropylene. In certain embodiments, at least one of the materials used to manufacture the battery is polycarbonate. In several embodiments, at least one of the materials used to manufacture the battery is propylene carbonate. In many embodiments, at least one of the materials used to manufacture the battery is polyoxomethylene. In some embodiments, at least one of the materials used to manufacture the battery is EPDM. In various embodiments, at least one of the materials used to manufacture the battery is polyurethane. In several embodiments, at least one of the materials used to manufacture the battery is nylon. In some embodiments, at least one of the materials used to manufacture the battery is PVC. In certain embodiments, at least one of the materials used to manufacture the battery is latex or natural latex rubber. In several embodiments, at least one of the materials used to manufacture the battery is gum rubber. In various embodiments, at least one of the materials used to manufacture the battery is Santoprene rubber or Santoprene. In several embodiments, at least one of the materials used to manufacture the battery is PMMA. In some embodiments, at least one of the materials used in manufacturing the battery is neoprene. In certain embodiments, at least one of the materials used in manufacturing the battery is PEEK. In several embodiments, at least one of the materials used in manufacturing the battery is sodium besylate. In some embodiments, at least one of the materials used in manufacturing the battery is sodium tosylate. In multiple embodiments, at least one of the materials used in manufacturing the battery is BUNA-N.

[0148] Polymers may contain additional additives such as plasticizers, colorants, fillers, and stabilizers to adjust their performance. For example, common additives in polyethylene and PVC include phthalates and adipicates. Perylenediimide anodices in many embodiments are compatible with common plasticizers, colorants, and fillers. [Redox flow battery]

[0149] A single cell of a redox flow battery may include two half-cells. One of the two half-cells may be a cathode half-cell and the other an anode half-cell. The cathode liquid (or cathode electrolyte) can be pumped to the cathode half-cell, and the anode liquid (or anode electrolyte) can be pumped to the anode half-cell. The cathode half-cell and the anode half-cell may be connected by a membrane for ion transport. The half-cell of the battery includes, but is not limited to, electrodes, gaskets, flow plates, diode plates, and membranes. According to several embodiments, any or all of the components of the half-cell can be made from a non-fluorinated polymer that is not specified to have high chemical resistance. In many embodiments, a redox flow battery may include at least one single cell, or at least two single cells, or at least five single cells, or at least ten single cells, or at least fifteen single cells, or at least twenty single cells, or at least twenty-five single cells, or at least thirty single cells, or at least fifty single cells, or at least one hundred single cells, or at least one fifty single cells.

[0150] In many embodiments, a redox flow cell may comprise a first half-cell containing an anode solution and a second half-cell containing a cathode solution, the anode solution comprising water-soluble perylenediimide molecules, and one or more of the cell components (e.g., electrodes, gaskets, flow frame, diode plates, membranes) may be made from materials not specified to have high chemical resistance. The redox flow cell may comprise at least one rigid material for the flow frame, rigid pipe connections and electrolyte tank, at least one flexible material for seals and flexible tubing, a conductive rigid material for the flow field, conductive porous electrodes, and membranes. In some embodiments, the cell components may be made from non-fluorinated polymers. In several embodiments, the non-fluorinated polymer may be polyolefins, polyethers, polyketones, polyamides, polyureas, natural rubber, or combinations thereof.

[0151] The flow frame of a redox flow battery is the reaction vessel where charging and discharging take place. The flow frame houses porous electrodes and is exposed to a flowing active electrolyte. In certain embodiments, the reaction vessel (flow frame) defining the interior of a half-cell of the battery can be made from at least one non-fluorinated polymer. Examples of non-fluorinated polymers that can be used to manufacture the flow frame include (but are not limited to) polyethylene, polypropylene, PMP, polybutene-1, PVC, polystyrene, PMMA, ABS, nylon, POM, polycarbonate, nylon, PEEK, or combinations thereof. In some embodiments, the reaction vessel can be made from a copolymer derived from two or more of the above polymers. In various embodiments, the flow frame can be made from titanium. In various embodiments, the flow frame can be made from a titanium-containing metal alloy. In several embodiments, the flow frame can be made from stainless steel.

[0152] The diodes in a redox flow battery are in direct contact with the electrolyte solution and collect current while separating the cells in the stack. It is desirable that the diodes have high chemical and mechanical stability, high electrical conductivity, and impermeability to prevent leakage. In vanadium redox flow batteries, isotropically molded graphite diodes have traditionally been used due to their good chemical stability in addition to electrical conductivity. However, isotropically molded graphite diodes are expensive to machine, and the graphite is brittle and highly porous, making them prone to breakage and leakage. In some embodiments, perylene diimide anodes allow the use of carbon-polymer composites or graphite resin blends in the manufacture of the diodes. In certain embodiments, the diodes in an anode half-cell, or in both an anode half-cell and a cathode half-cell, can be made from extruded graphite. In several embodiments, the diodes in an anode half-cell, or in both an anode half-cell and a cathode half-cell, can be made from graphite / polymer composites. Graphite / polymer composites can be injection molded or bulk molded. In certain embodiments, the graphite / polymer composite is resin-filled graphite. In several embodiments, the polymer of the graphite / polymer composite is polyethylene or polypropylene.

[0153] The gasket is a rubber seal placed between each layer of a half-cell (for example, between the flow frame and the electrode plates). In many embodiments, the gasket in an anodeliquid half-cell, or in both an anodeliquid half-cell and a cathodeliquid half-cell, comes into contact with the electrolyte solution and may include a non-fluorinated elastomer material. In some embodiments, the non-fluorinated elastomer material may include, but is not limited to, EPDM, Santoprene, neoprene, BUNA-S, BUNA-N, latex, trans-isoprene, PUR, and polyurethane, which are non-highly chemical-resistant rubber materials.

[0154] In redox flow batteries, the membrane separates the anode and cathode. The membrane is desirable to prevent crossover of active species in each half-cell and to have high ionic conductivity, low area electrical resistance, and good chemical stability. In several embodiments, the membrane may be an ion exchange membrane or a size exclusion membrane. In some embodiments, the membrane can be made from a non-fluorinated polymer. In several embodiments, the membrane can be made from hydrocarbon polymers including, but not limited to, polyethylene, polypropylene, and polystyrene. These hydrocarbon membranes include, but are not limited to, ammonia-modified polystyrene, sulfonated polystyrene, and sulfonated polyether ketones, which are non-fluorinated charge conductors.

[0155] In many embodiments, the membrane frame of a redox flow cell can be made from a non-fluorinated polymer. In several embodiments, the membrane frame can be made from a non-fluorinated polymer including (but not limited to) polyethylene, polypropylene, PMP, polybutene-1, PVC, polystyrene, PMMA, ABS, nylon, POM, polycarbonate, PEEK, or combinations thereof. In some embodiments, the membrane frame can be made from a copolymer derived from two or more of the above polymers.

[0156] A redox flow battery may include supply lines and / or tubes positioned outside the anode and cathode to supply electrolyte to the battery and return the electrolyte to a storage tank. In several embodiments, the supply lines of a redox flow battery can be made from non-high chemical-resistant materials. In certain embodiments, the supply lines can be constructed from non-fluorinated polymers. In some embodiments, the supply lines can be made from non-fluorinated elastomer materials. In various embodiments, the non-fluorinated elastomer materials may be non-high chemical-resistant rubber materials including, but not limited to, EPDM, Santoprene, Neoprene, BUNA-S, BUNA-N, latex, trans-isoprene, PUR, and polyurethane.

[0157] A redox flow battery may include a supply manifold and an electrolyte tank for supplying the electrolyte. In many embodiments, the supply manifold and / or electrolyte tank can be made from at least one non-fluorinated polymer. Examples of non-fluorinated polymers that can be used to manufacture the flow frame include, but are not limited to, polyethylene, polypropylene, PMP, polybutene-1, PVC, polystyrene, PMMA, ABS, nylon, POM, polycarbonate, nylon, PEEK, or combinations thereof. In some embodiments, the supply manifold and / or electrolyte tank can be made from a copolymer derived from two or more of the above polymers.

[0158] In a redox flow battery, the number of cells (cell stack) determines the system's power output (watts), and the electrolyte is housed in a tank, with the tank size potentially determining the energy (watt-hours). This separation of power and energy in the design may be an advantage that allows for easy scaling up of redox flow batteries. Figure 1 is a schematic diagram of a redox flow cell using a non-highly chemical-resistant material according to one embodiment. The redox flow cell is connected to a cathode liquid reservoir and an anode liquid reservoir. The flow cell houses a dipole plate 101, a flow frame 102, a porous electrode 103, a membrane and membrane frame 104, and a gasket (seal layer) 105. The electrolyte (anode or cathode liquid) solution can flow through the inlet of a conductive current collector plate (in the case of a single cell) or the dipole plate (in the case of a cell stack). The plate can be fabricated with a flow field that helps distribute the electrolyte as it diffuses into the carbon felt electrode. The electrode is housed within the non-conductive flow frame 102. The flow frame 102 may be a chamber from which the electrolyte can be charged and discharged. The flow frame 102 is separated from the other half of the cell by an ion-conductive membrane 104 that allows the crossing of charged ions but retains electrolyte molecules. The electrolyte is then diffused from the electrodes and discharged from an outlet 107 on the opposite side of the current collector plate or dipole plate 101. The two half-cells can be pressed together so that each layer is in contact with a gasket 105 that prevents leakage.

[0159] In conventional vanadium redox flow batteries, the electrode plates can be made from isotropically formed graphite, the flow frame from PTFE, the porous electrodes from carbon felt, and the membrane from Nafion. TM It can be manufactured from various materials; the membrane frame can be made from PTFE, and the gasket (seal layer) can be made from Viton rubber.

[0160] In many embodiments, redox flow batteries utilize perylenediimide molecules in the anode liquid for charge storage, and the cells can be fabricated from non-fluorinated and low-cost materials. In several embodiments, the electrode plate 101 can be fabricated from a resin-filled graphite composite, the flow frame 102 can be fabricated from polypropylene, the porous electrode can be fabricated from carbon felt, and the membrane 104 is made of Selemion. TM It can be manufactured from, and gasket 105 can be manufactured from Santoprene. Polypropylene is a widely used melt-molded thermoplastic. Polypropylene is inexpensive, can be mass-produced, and is more rigid than polyethylene. In certain embodiments, backplates, flow frames, hose connectors, and / or electrolyte tanks can be constructed from polypropylene. Santoprene is a thermoplastic vulcanized elastomer containing EPDM rubber encapsulated in a polypropylene matrix. By adding polypropylene to this material, costs are reduced compared to pure EPDM, and Santoprene can melt and function like a thermoplastic. Santoprene is commonly used as a component of seals, hoses, and flexible connectors. According to some embodiments, Santoprene can be used in seals and flexible tubes. Impregnated graphite is cheaper than the pyrolysis-grade graphite required for corrosive vanadium redox flow batteries. As an ion exchange membrane, Selemion TM AMVN is available. (Selemion) TMAMVNs are water desalination membranes that are stable in mild, pH-neutral electrolytes. These materials significantly reduce the cost of each of these components. In many embodiments, the manufacturing cost of redox flow battery components is significantly lower than that of redox flow batteries made with conventional vanadium redox flow battery materials.

[0161] Figure 2 shows the components and assembled redox flow cell according to one embodiment of the present invention. The end plate (a) can be made from aluminum and functions as a press that provides sealing pressure to the cell when bolted together. The cell back plate (b) can be constructed from polypropylene and functions as an insulating layer between the current collector plate and the metal press, and also provides a surface that connects the fluid inlet and fluid outlet (via a polypropylene barb connector). A flat Santoprene seal (c) is placed between this layer and the current collector plate. Conventional vanadium-based seals are made from fluorinated elastomers such as PFA or Viton because the battery medium is corrosive. In many embodiments, inexpensive Santoprene seals are used in redox flow batteries. The current collector plate (d) is machined with a flow field and has inlet and outlet holes for supply. Resin-impregnated graphite can be used for the electrode plate or current collector plate. Resin-impregnated graphite is liquid-tight and is less expensive than high-grade isotropically molded graphite, in which the resin degrades due to acidic electrolytes. The current collector plate is separated from the flow frame by another Santoprene gasket (e). The flow frame can be constructed from polypropylene and has a space for the carbon felt electrode (g) to be installed. These components constitute one side of the cell and are separated from the other side by a membrane (h). The membrane is a polystyrene-based membrane called Selemion. TM AMVN is available. The other side of the cell has a mirror image structure of the other side, and the cell configuration is shown in Figure 2. The total area of ​​the cell (1 inch circle) is approximately 5 cm². 2 , or about 5cm 2 Less than, or about 5 cm 2 Super, about 5cm 2 From approximately 100cm 2, about 100cm 2 Super, about 100cm 2 From approximately 500cm 2 , about 500cm 2 From approximately 1500cm 2 , about 1500cm 2 In some cases, the tubes supplying the cells via the centrifugal pump can be made from polymers including (but not limited to) PVC, and the electrolyte supply tank can be made from plastic, polymer, or glass. [Redox flow battery performance]

[0162] The perylenediimides disclosed herein provide stability for long-life redox flow batteries. The ferrocenes disclosed herein provide stability for long-life redox flow batteries. As used herein, the term “long-life” means a battery that has a stable capacity retention rate over repeated charge-discharge cycles or elapsed time. In some embodiments, a redox flow battery may have a lifespan of at least 5 years, or at least 10 years, or at least 20 years, or at least 50 years, or 5 to 50 years, or 5 to 50 years, or 20 to 50 years.

[0163] Coulomb efficiency is a direct measure of molecular stability in organic flow batteries. Coulomb efficiency is the ratio of electrons discharged from a battery to the number of electrons injected into it. For example, if a battery discharges 99 electrons from 100 electrons charged into a device in a given cycle, its Coulomb efficiency is 99%. This can be a direct measure of molecular stability in organic flow batteries. Electrons can be lost through various pathways other than molecular decomposition, such as solution leakage from the cell or crossover of active species across the membrane. However, molecular decomposition is observed as a decrease in Coulomb efficiency. Not all decreases in Coulomb efficiency are due to molecular decomposition, but it can cause a decrease. If the cause of the decrease in Coulomb efficiency is leakage, the molecule may be more stable than indicated by the Coulomb efficiency. Conversely, the molecule cannot be more unstable than indicated by the Coulomb efficiency. Any molecular decomposition results in a decrease in Coulomb efficiency. Examples of such decomposition include the disappearance of organic radicals on charged molecules through destructive chemical events such as dimerization, the formation of permanent bonds using two radicals, or attack by a solvent. If the Coulomb efficiency indicates a lifetime of 500 years, the molecular stability may be 750 years, but the molecular stability will never be shorter than the 500 years indicated by the Coulomb efficiency.

[0164] In many embodiments, redox flow batteries comprising a stable, water-soluble perylenediimide anode and a stable, water-soluble ferrocene exhibit high Coulomb efficiency at a neutral pH (approximately pH 7) or near-neutral pH (approximately pH 6 to approximately pH 8, or approximately pH 5.5 to approximately pH 8.5). In several embodiments, the Coulomb efficiency of the redox flow battery may be at least 98% after at least approximately 200 charge / discharge cycles, or at least 380 charge / discharge cycles. In some embodiments, the Coulomb efficiency may be at least 98.5% after at least approximately 200 charge / discharge cycles, or at least 380 charge / discharge cycles. In certain embodiments, the Coulomb efficiency is at least 99% after at least approximately 200 charge / discharge cycles, or at least 380 charge / discharge cycles. In several embodiments, the Coulomb efficiency is at least 99.5% after at least approximately 200 charge / discharge cycles, or at least 380 charge / discharge cycles. In some embodiments, the Coulomb efficiency is at least 99.6% after at least about 200 charge / discharge cycles, or at least 380 charge / discharge cycles. In certain embodiments, the Coulomb efficiency is at least 99.7% after at least about 200 charge / discharge cycles, or at least 380 charge / discharge cycles. In many embodiments, the Coulomb efficiency is at least 99.9% after at least about 200 charge / discharge cycles, or at least 380 charge / discharge cycles. In some embodiments, the Coulomb efficiency is about 100% after at least about 200 charge / discharge cycles, or at least 380 charge / discharge cycles. In several embodiments, the Coulomb efficiency is about 98.5% to about 99.5% after at least about 200 charge / discharge cycles, or at least 380 charge / discharge cycles. In certain embodiments, the Coulomb efficiency is approximately 99% to approximately 99.5% after at least approximately 200 charge / discharge cycles, or at least 380 charge / discharge cycles.In several embodiments, the Coulomb efficiency is approximately 99.5% to 99.9% after at least approximately 200 charge / discharge cycles, or at least 380 charge / discharge cycles.

[0165] Many embodiments of redox flow batteries exhibit high Coulomb efficiency, enabling longer lifespans for charge storage species within the battery. In several embodiments, the half-life of the species within the battery (i.e., the time required for the battery's charge storage capacity to be halved due to molecular degradation) can exceed approximately 10 years. In some embodiments, the half-life of charge storage material for redox flow batteries can exceed approximately 20 years. In certain embodiments, the half-life of charge storage material for redox flow batteries can exceed approximately 50 years. In some embodiments, the half-life of charge storage material for redox flow batteries can exceed approximately 70 years. In several embodiments, the half-life of charge storage material for redox flow batteries can exceed approximately 100 years. In various embodiments, the half-life of charge storage material for redox flow batteries can exceed approximately 200 years. In many embodiments, the half-life of charge storage material for redox flow batteries can exceed approximately 500 years. In some embodiments, the half-life of charge storage material for redox flow batteries can exceed approximately 1,000 years. In several embodiments, the half-life of the charge storage material for redox flow batteries can exceed about 2,000 years. In certain embodiments, the half-life of the charge storage material for redox flow batteries can exceed about 3,000 years. In some embodiments, the half-life of the storage material for redox flow batteries of this disclosure can exceed about 5,000 years. In multiple embodiments, the half-life of the charge storage material for redox flow batteries is between about 50 years and about 100 years. In some embodiments, the half-life of the charge storage material for redox flow batteries is between about 100 years and about 500 years. In various embodiments, the half-life of the charge storage material for redox flow batteries is between about 500 years and about 1,000 years. In some embodiments, the half-life of the charge storage material for redox flow batteries is between about 1,000 years and about 2,000 years. In several embodiments, the half-life of the charge storage material for redox flow batteries is between approximately 2,000 and 3,000 years. In certain embodiments, the half-life of the charge storage material for redox flow batteries is between approximately 2,000 and 5,000 years.

[0166] The performance of a redox flow battery can be evaluated by its capacity retention rate. If the loss of charge storage capacity over multiple charge / discharge cycles of a redox flow battery is minimal, it can be guaranteed to have a sufficient lifespan. In many embodiments, the loss of charge storage capacity over numerous charge / discharge cycles of a redox flow battery is minimal. In some embodiments, the loss of charge storage capacity after approximately 300 or 380 full charge / discharge cycles of a redox flow battery is less than approximately 2%. In several embodiments, the loss of charge storage capacity after approximately 300 or 380 full charge / discharge cycles of a redox flow battery is less than approximately 1%. In certain embodiments, the loss of charge storage capacity after approximately 300 or 380 full charge / discharge cycles of a redox flow battery is less than approximately 0.5%. In various embodiments, the loss of charge storage capacity after approximately 300 full charge / discharge cycles or approximately 380 full charge / discharge cycles of a redox flow battery is less than approximately 0.25%. In several embodiments, the loss of charge storage capacity after approximately 300 full charge / discharge cycles or approximately 380 full charge / discharge cycles of a redox flow battery is less than approximately 0.1%. In some embodiments, the loss of charge storage capacity after approximately 300 full charge / discharge cycles or approximately 380 full charge / discharge cycles of a redox flow battery is less than approximately 0.05%. In several embodiments, the loss of charge storage capacity after approximately 300 full charge / discharge cycles or approximately 380 full charge / discharge cycles of a redox flow battery is less than approximately 0.03%. In some embodiments, the loss of charge storage capacity after approximately 300 full charge / discharge cycles or approximately 380 full charge / discharge cycles of a redox flow battery is less than approximately 0.01%. In certain embodiments, the loss of charge storage capacity after approximately 300 full charge / discharge cycles or approximately 380 full charge / discharge cycles of a redox flow battery is between approximately 0.05% and approximately 0.1%.In several embodiments, the loss of charge storage capacity after approximately 300 full charge / discharge cycles or approximately 380 full charge / discharge cycles of a redox flow battery is approximately 0.03% to approximately 0.1%. In some embodiments, the loss of charge storage capacity after approximately 300 full charge / discharge cycles or approximately 380 full charge / discharge cycles of a redox flow battery is approximately 0.01% to approximately 0.05%.

[0167] In many embodiments, the loss of charge storage capacity during operation of a redox flow battery is minimal. In some embodiments, the loss of charge storage capacity of a redox flow battery is less than approximately 2% per year. In several embodiments, the loss of charge storage capacity of a redox flow battery is less than approximately 1% per year. In certain embodiments, the loss of charge storage capacity of a redox flow battery is less than approximately 0.5% per year. In certain embodiments, the loss of charge storage capacity of a redox flow battery is less than approximately 0.25% per year. In some embodiments, the loss of charge storage capacity of a redox flow battery is less than approximately 0.1% per year. In several embodiments, the loss of charge storage capacity of a redox flow battery is less than approximately 0.05% per year. In certain embodiments, the loss of charge storage capacity of a redox flow battery is less than approximately 0.03% per year. In some embodiments, the loss of charge storage capacity of a redox flow battery is less than approximately 0.01% per year. In various embodiments, the loss of charge storage capacity of the redox flow battery is approximately 0.05% to approximately 0.1% per year. In several embodiments, the loss of charge storage capacity of the redox flow battery is approximately 0.03% to approximately 1% per year. In various embodiments, the loss of charge storage capacity of the redox flow battery is approximately 0.01% to approximately 0.05% per year. [Example Embodiments]

[0168] The following embodiments are provided to provide a complete disclosure and explanation of how those skilled in the art can manufacture and use the present invention, and are not intended to limit the scope of what the inventors consider to be their invention, nor to indicate that the experiments described below represent all or only experiments performed. While efforts have been made to ensure the accuracy of the numerical values ​​used (e.g., quantities, temperatures, etc.), some experimental errors and deviations should be taken into consideration. [Example 1: Non-high chemical-resistant material]

[0169] In many embodiments, readily available and easily manufactured common plastics and rubber materials are used in redox flow batteries. Various plastics, rubbers, and small molecules are suitable for redox flow batteries due to the mild operating conditions of the battery, such as the neutral electrolyte solution and non-corrosive redox molecules. Examples of plastics suitable for redox flow batteries include (but are not limited to) nylon, PEEK, POM, PVC, PE, PMMA, and PP. Plastic materials in some embodiments can be used to construct liquid contact parts such as flow frames, supply manifolds, and electrolyte tanks. Examples of flexible materials (rubber and elastomers) include (but are not limited to) EPDM, neoprene, silicone, BUNA-N, latex, PUR, and Santoprene. Flexible materials in several embodiments can be used for seals, tubes, and other parts in the battery system where flexibility is required. Examples of metals include (but are not limited to) 316 stainless steel, 6061 aluminum, Hastelloy, and Grade 2 titanium. In some embodiments, small molecules comprising (but not limited to) sodium besylate, sodium tosylate, propylene carbonate, and sulfolane are provided, which are compatible with redox flow batteries. The small molecules can be added to the electrolyte solution at concentrations several times higher than those of the charge carrier molecules for stability testing. These small molecules represent functional groups to ensure that the electrolyte does not interact with a particular class of structures in high-concentration stress tests. Sodium besylate is a form of sodium aromatic sulfonate salt, and SelemionTM This represents the functional groups grafted onto the polystyrene backbone of the AMVN anion exchange membrane. Adding this in excess allows for the determination of inherent stability issues with aryl sulfonates present in or leaching from the anion exchange membrane. Sodium tosylate has an additional structural motif, a benzyl carbon (methyl group), and functions as a water-soluble test reagent to evaluate the stability of this position, which can undergo radical-promoting reactions under certain conditions. Propylene carbonate and sulfolane are non-volatile solvents of interest from the perspective of viscosity reduction properties. The chemical structures of each material are shown in Table 1. The stability of the materials is evaluated by the H-cell cycle test and high SOC exposure test, which are detailed below. [Table 1-1] [Table 1-2] [Table 1-3] [Example 2. H-cell experiment]

[0170] In many embodiments, a redox flow cell (including, but not limited to, an H cell) is implemented to test the compatibility of an electrolyte solution with cell manufacturing material in both charged and uncharged states by exposing the material within a glass H cell containing a membrane. The cell manufacturing material is placed in a half-cell of the H cell for compatibility analysis. This static cell experiment setup allows for accurate measurement of Coulomb efficiency for analyzing the electrochemical and physical compatibility of the charged electrolyte solution with the cell manufacturing material. High Coulomb efficiency indicates that electrons introduced into the organic charge storage electrolyte during charging are returned during discharge, meaning that the electrolyte does not react electrochemically or physically with the cell manufacturing material in the charged state, thereby preventing charge loss. In addition, this static cell experiment allows for sampling of the H cell by taking small samples over time and performing high-performance liquid chromatography (HPLC) analysis. This analysis shows that the charged electrolyte reacts with various materials in the cell to generate new molecular species. The absence or slow generation of new molecular species indicates compatibility.

[0171] A glass H-cell with a theoretical capacity of 1 mAh can be used for material stability testing. Figure 3A shows the various components of the H-cell. Figure 3B shows the assembled H-cell. The H-cell includes two glass chambers, a metal clamp, a membrane, two carbon felt electrodes connected to a battery cycler via platinum wire, two PTFE stirrers, two Viton O-rings, and two scepter caps. To assemble the H-cell, the two glass chambers are connected with a metal clamp, with the membrane in between to separate the two sides. One side becomes the anode half-cell, and the other side becomes the cathode half-cell. The membrane can be sealed with one Viton O-ring on each side. One PTFE-coated stirrer can be placed in each glass chamber of the H-cell. A thin platinum wire is inserted through the scepter cap to connect an external load to the carbon felt electrode. This carbon felt electrode is secured to the end of the platinum wire through the scepter cap. Scepter caps can then be attached to both the anode and cathode. Empty H cells without electrodes can be assembled outside the glovebox. Empty H cells can be transferred to the glovebox after being subjected to at least three substitution and refilling cycles in a nitrogen atmosphere in the front chamber of the glovebox. Felt electrodes can be attached to platinum wires at both the anode and cathode, and the cells can be filled with deoxygenated anodic and cathode solutions.

[0172] The anode solution and cathode solution are electrolytes used at the anode and cathode of the H cell, respectively. The anode solution may be perylenediimide (PDI) and / or any perylenediimide according to many embodiments. The cathode solution may be ferrocene and / or any ferrocene derivative according to several embodiments. In some embodiments, PDI-tetraammonium-Cl4 is mounted in the anode solution half-cell and ferrocene-diammonium-Cl2 is mounted in the cathode solution half-cell for H cell testing. For ease of understanding, any form of PDI derivative may be used for the anode solution and any form of ferrocene derivative may be used for the cathode solution to suit the specific application requirements according to various embodiments of the present invention. The electrolytes can be dissolved in about 1 M sodium chloride for electrochemical stability testing. The number of moles of anode solution and cathode solution molecules present can be controlled to achieve a desired capacity of 1 mAh. During the charge-discharge cycle, PDI-tetraammonium-Cl4 accepts and donates 2 electrons per molecule, while ferrocene-diammonium-Cl2 accepts and donates only 1 electron per molecule. Therefore, the molar concentration of PDI-tetraammonium-Cl4 in the H cell is half the molar concentration of ferrocene-diammonium-Cl2. The H cell contains Selemion TM Anion exchange membranes (AMVNs) can be used. (Selemion) TM AMVN is a polystyrene-based ion exchange membrane. Materials used to construct H cells, such as glass, vitone, PTFE, platinum, and carbon, did not show undesirable interactions with electrolytes in cycle tests.

[0173] In the H-cell suitability test, the anode and cathode sides each contain approximately 7 mL of anodic and cathode liquid. After attaching rod electrodes to the H-cell and filling the glove box with electrolyte, the H-cell can be connected to the battery test system. The H-cell can be placed on an electromagnetic stirrer before the cycle. The operating temperature of the H-cell is approximately 30°C to 38°C. The capacity of the H-cell may vary slightly from test to test and may depend on the electrolyte refresh rate (or stirrer rotation speed), electrode position, and operating temperature variations.

[0174] The H-cell test method includes constant current and constant voltage protocols. The H-cell can first be left standing for about 10 seconds, and then charged with a constant current of about 0.25 mA (corresponding to a charge level of about 0.25 C). Once the voltage reaches about 1 V, it can be left standing for another 30 seconds. Next, a constant voltage charge of about 1 V can be applied until the charging current drops to about 0.05 mA (corresponding to a charge level of about 0.05 C). After that, the H-cell can be fully charged and left standing at the open-circuit voltage for about 30 seconds. For discharge, a two-stage current method can be employed. The H-cell is discharged with a constant current of about 0.25 mA until the voltage drops to about 0.1 V, and then discharged slowly until the discharge current is less than about 0.05 mA. After the completion of the first charge-discharge cycle, the same test protocol can be continued for the next cycle.

[0175] After performing several cycles to establish a baseline, the charge-discharge cycle test is paused, the two septa caps are opened, a small piece of one material is placed into both chambers of the H-cell, and the two septa caps are replaced. The charge-discharge cycle test of the H-cell can then be resumed. The cycle test may be continued for at least two weeks. During the test period, the Coulomb efficiency and capacity are monitored. If a Coulomb efficiency of more than 99.9% cannot be maintained, the material is considered incompatible with the electrolyte according to the various embodiments.

[0176] H-cell cycle tests in many embodiments demonstrated the suitability of various materials, with average Coulomb efficiencies exceeding approximately 99.9% during battery cycles spanning several weeks. This material suitability provides a diverse range of effective choices for structural elements of battery systems. Examples of suitable rigid materials include (but are not limited to) nylon, PEEK, POM, PVC, PE, PMMA, and PP. These suitable materials enable easily manufactured and low-cost redox flow batteries. Materials including (but not limited to) nylon, PE, and PP can be used as 3D printing filaments for rapid prototyping of elements such as liquid supply manifolds and flow frames. Examples of suitable flexible materials include (but are not limited to) EPDM, neoprene, BUNA-N, natural latex rubber, PUR, and Santoprene. Flexible materials can be used for flexible components of redox flow batteries, including (but not limited to) tubing and seals. However, not all test materials are suitable for redox flow batteries in many embodiments. In certain embodiments, silicone exhibits a Coulomb efficiency of approximately 99.89% during H-cell testing. The Coulomb efficiency of silicone in redox flow batteries falls below the desired value of approximately 99.9%, and therefore silicone may not be stable enough to provide the desired lifespan of at least 20 years. Examples of suitable small molecules include (but are not limited to) sodium besylate, sodium tosylate, propylene carbonate, and sulfolane. The stability of sodium besylate and sodium tosylate is demonstrated by Selemion. TMThis demonstrates that aryl sulfonic acid in the AMVN film does not adversely affect the stability of the cycle battery. In addition, the stability of sodium tosylate demonstrates the stability of the benzylmethyl group as a common motif. Cosolvents can be added to the electrolyte composition to improve solution properties such as viscosity, solubility, and volatility. Examples of suitable cosolvents include (but are not limited to) propylene carbonate and sulfolane. The compatibility of propylene carbonate with redox flow batteries demonstrates the compatibility of common carbonate groups, meaning that polycarbonate plastics and other carbonate-containing molecules can be stable. In some embodiments, metals such as 316 stainless steel and 6061 aluminum have been shown to be potentially unsuitable for the liquid contact parts of redox flow batteries. These alloys contain various transition metals and elements that can be electrochemically oxidized and reduced. When the battery is charged, electrons can move from redox molecules in the electrolyte to these metallic materials, potentially causing degradation. In several embodiments, any metal material used in a redox flow battery can be coated with a compatible plastic or rubber material, including (but not limited to) nylon, PEEK, POM, PVC, PE, PMMA, PP, EPDM, neoprene, BUNA-N, latex, Santoprene, polyurethane, and any combination thereof.

[0177] Figure 4A shows the results of an H-cell cycle test using nylon according to one embodiment of the present invention. Figure 4A shows that the Coulomb efficiency was approximately 99.95% after performing an H-cell cycle using nylon for approximately 19.9 days. The average Coulomb efficiency was approximately 99.95% over approximately 20 days, and the discharge capacity (orange line) and charge capacity (blue line) matched in each cycle after nylon was added to the cell. As shown in Figure 4A, the cell capacity remained flat, and no degradation of the nylon was detected under the operating conditions of the redox flow battery.

[0178] Figure 4B shows the results of an H-cell cycle test using 316 stainless steel according to one embodiment of the present invention. Figure 4B shows that the Coulomb efficiency was approximately 99.32% after an H-cell cycle using 316 stainless steel for approximately 12.9 days. The Coulomb efficiency of the steel test was approximately 99.32%, and the decreasing trend in capacity is clear. The capacity loss of 316 stainless steel in the redox flow battery shown in Figure 4B may be due to discharge to the steel, chemical reactions between the electrolyte and the steel, and / or adsorption of active species to the steel. When the battery capacity falls below 99.9% efficiency, a redox flow battery with steel in contact with the electrolyte solution may be too unstable.

[0179] Table 2 summarizes the results of H-cell cycle tests for exemplary materials. If the Coulomb efficiency is approximately 99.9% or higher after at least 14 days of H-cell testing, the material is considered stable. If the Coulomb efficiency is less than approximately 99.9% after at least 14 days of H-cell testing, the material is considered unstable. [Table 2] [Example 3. High-Charge Exposure Test]

[0180] Materials that pass the H-cell cycle test can undergo a high-SOC exposure test to assess their compatibility with a fully charged electrolyte over a long period. In the high-SOC test, the H-cell can be charged to 100%. The cycle is then stopped, and the fully charged anode and cathode can be transferred to separate vials. An additional vial containing approximately 1.0 M NaCl in water can be used as a reference. Each of the three vials can contain a small amount of material, representing a significant mass excess compared to the electrolyte molecules present in the solution. Small samples are periodically taken from these three vials and analyzed by HPLC to monitor chemical changes resulting from the charging species' exposure to the test material. The NaCl control solution can be used to monitor components that dissolve from the material in brine, which may interact with the electrolyte. Additionally, both electrolytes change color during discharge, allowing for a rapid and qualitative assessment of their stability. Since the high-SOC test does not require a battery cycler, the cycler channel can be allocated to H-cell experiments, allowing for workflow parallelization. Figure 5 shows a process that combines H-cell testing and high SOC exposure testing for a given material.

[0181] The stability, and thus usefulness, of each material that showed good results in the H-cell cycle test (Table 2) can be further investigated using high-SOC exposure tests. These tests are performed by storing the charged electrolyte in contact with the test material for up to approximately 133 days. The test results show interactions that may occur on a longer timescale than the initial cycle tests. For example, any interaction that adversely affects battery life, such as chemical reactions between electrolyte molecules and the material, or chemical reactions between electrolyte molecules and leaches or degradation products dissolved from the material into the solution, will inevitably generate new chemical species in the solution, which can be detected by HPLC. In addition, leaches and degradation products from materials in contact with saline solution, even if harmless, are easily detected. If no new chemical products are detected in the anodic or cathode solution, and no leaches or degradation products are observed in the saline control experiment, it can be concluded that no chemical degradation occurred over the test period in contact with the material. During the high-SOC test, a small amount of electrolyte, approximately 15 milligrams, is present for several hundred milligrams of test material such as plastic and / or rubber.

[0182] High SOC testing can be performed in parallel with H-cell testing. For example, polystyrene and polycarbonate can be tested by filling H-cells to 100% SOC, dispensing the electrolyte into small vials, and then placing and storing the material in them. The results of high SOC exposure tests using PDI-tetraammonium-Cl4 (PDI-XL-2), ferrocene-diammonium-Cl2 (Fc-XL-2), and sodium chloride control solutions are summarized in Table 3. Materials that showed suitability in H-cell testing also showed good results in exposure tests. In addition, any species leaching from the materials into pure salt water were below the detection limit. [Table 3]

[0183] HPLC testing was performed on all test materials. Figures 6A to 6C show the HPLC results over time for high SOC exposure tests of PDI-tetraammonium-Cl4, ferrocene-diammonium-Cl2, and NaCl control solutions, which were left standing in contact with EPDM rubber according to one embodiment of the present invention. Figure 6A shows the HPLC results over time for the high SOC exposure test of PDI-tetraammonium-Cl4 in contact with EPDM rubber. Figure 6B shows the HPLC results over time for the high SOC exposure test of ferrocene-diammonium-Cl2 in contact with EPDM rubber. Figure 6C shows the HPLC results over time for the high SOC exposure test of NaCl in contact with EPDM rubber. Since the samples are diluted to concentrations suitable for HPLC, slight variations in total peak absorbance may occur. Therefore, the chromatograms are normalized to the maximum peak height of the sample that shows the strongest absorbance at the detection wavelength. Furthermore, because retention times vary subtly with slight changes in temperature and concentration, the time is normalized so that the maximum product peaks for PDI-tetraammonium-Cl4 and ferrocene-diammonium-Cl2 coincide. To more directly compare the concentration of any leachate in the brine blank with the concentration of electrolyte molecules, the brine data is presented on the same scale as the ferrocene-diammonium-Cl2 data. All chromatography was performed on a C-18 reversed-phase column, and elution conditions were developed separately for PDI-tetraammonium-Cl4 and ferrocene-diammonium-Cl2, respectively. The ferrocene-diammonium-Cl2 method was used for the brine control experiments. Some HPLC spectra contain solvent-front-induced peaks with short retention times and randomly fluctuating intensity. These signals are due to changes in the UV absorption of the carrier solvent during injection and do not correspond to chemical species present in the analyte.

[0184] For PDI-tetraammonium-Cl4, the HPLC chromatogram remains unchanged even after a very long period (approximately 19 weeks) of exposure to EPDM. The small peak 601, visible at approximately 1.8 minutes, is the solvent front at injection and, unlike true impurities or degradation products, its intensity does not increase over time but rather fluctuates randomly between samples. This broadened, tailed peak shape is typical of PDI molecules and is due to aggregation in solution.

[0185] Furthermore, the results for ferrocene-diammonium-Cl2 exposed to EPDM were also good. Similar to the case of PDI-tetraammonium-Cl4, the earliest elution peak was at the solvent front at injection, which was independent of concentration or time and varied greatly from sample to sample. This peak 602 also appeared when uncharged ferrocene-diammonium-Cl2 was dissolved in brine. This is thought to be due to the elution of the column and trace products at the solvent front in brine. When polar ferrocene-diammonium-Cl2 was mixed with NaCl, it initially eluted very rapidly on the reversed-phase column. After the NaCl was washed and some of the ferrocene-diammonium-Cl2 co-eluted, the remaining ferrocene-diammonium-Cl2 was retained on the column and eluted as a single peak around 8 minutes. A small, sharp signal was also observed around 18 minutes. This signal did not increase with time and was observed even in brine unexposed to any test material, suggesting that it is an artifact (peak) caused by the HPLC column and system and is common to all samples. This peak appears even in the absence of ferrocene-diammonium-Cl2, therefore it is not a decomposition product. This indicates that no new products have been formed. [Example 4. Performance of the redox flow cell]

[0186] The compatible materials used in constructing the redox flow cell show no signs of degradation, and after approximately 20 days of testing, the flow cell exhibits an average Coulombic efficiency of approximately 100%. According to several embodiments, the electrolyte supply tank of the flow cell can be filled with PDI-tetraammonium-Cl4 as the anodelite and ferrocene-diammonium-Cl2 as the cathodelite. The flow rate can be set to approximately 10 mL / min, and the battery can be cycle-tested in the same manner as in H-cell stability testing.

[0187] Figure 7 shows cycle data from a 10mAh flow cell according to one embodiment of the present invention. Initially, there was a mismatch in pump operation, causing a slight delay in data acquisition. However, after equilibration, electrolyte supply was maintained and the cycle test commenced. The flow cell was cycled for approximately 20 days, totaling approximately 380 cycles. In this long-term cycle test shown in Figure 7, a high Coulomb efficiency of over 99.9% was confirmed. The average Coulomb efficiency was approximately 100%. [Example 5: Battery manufactured from non-high chemical-resistant material]

[0188] A battery was constructed consisting of a flow cell containing two non-porous resin-filled graphite dielectrode plates in contact with graphite felt separated by a FumasepFAPQ anion exchange membrane. The chambers housing the electrodes and graphite felt were constructed from polypropylene, with layers sealed with Santoprene rubber and polypropylene / EPDM elastomer. The graphite plates were perforated with inlets and outlets to allow the electrolyte solution to flow into and out of the two chambers separated by a separator. Rigid fixtures and piping were constructed from polypropylene, and flexible tubing used for electrolyte delivery was made from Santoprene rubber. Flow rate was provided by a peristaltic pump compressing the Santoprene rubber tubing. The electrolytes were dissolved in 5 mL each of 0.5 M NaCl aqueous solution and stored in a glass storage tank. The chemical structures of the anolyte (PDI-tetraammonium-Cl4) and cathodelyte (ferrocene-diammonium-Cl2) used are shown below. These solutions were pumped through the flow cell at a rate sufficient for charging and discharging. This cell was continuously charged and discharged for 14 days, and as shown in Figures 8A and 8B, the capacity retention rate was 97% and the total Coulomb efficiency was 99.99%. This example demonstrates that the electrolyte solution is stable even when in contact with these non-highly chemical-resistant materials. [ka] [ka] [Example 6: Perylenediimide molecules in a two-electron reduced state are compatible with non-highly chemical-resistant materials.]

[0189] In a battery similar to that of Example 5, the anode solution was highly charged on one side of a glass H-cell equipped with carbon felt electrodes and a platinum current collector. The anode solution was separated from the cathode solution by a Selemion ion exchange membrane. After charging, the anode material was removed from the electrochemical cell, and a dispensed portion of this solution was placed in glass sample vials that had been in contact with different material samples. At this time, the total mass of each material was much larger than the total mass of the charged electrolyte molecules in the sample. In the highly charged state, the anode solution is dark purple, while uncharged anode solution is bright red. This difference in color allows for easy determination of the charge state of any anode solution. After 5 months of contact, the anode samples in contact with polypropylene, polyurethane, polyethylene, Santoprene rubber, and control samples of the anode solution alone all remained purple, indicating no or incomplete disappearance of radical species, thus confirming that the anode solution is stable even when in contact with these materials. [Example 7: HPLC experiment to evaluate chemical stability]

[0190] In this example, the compatibility of battery materials is evaluated by high-performance liquid chromatography (HPLC). Chromatograms of the electrolyte solution after contact in a neutral or charged state indicate minimal or no decomposition of the material into the solvent, nor decomposition of the electrolyte into new chemical species. Test materials include ABS, BUNA-N, EPDM, latex, neoprene, nylon, polyethylene, PEEK, polycarbonate, polypropylene, polystyrene, POM, polyurethane, PVC, Santoprene, silicone, and titanium. Material compatibility is summarized in Table 3.

[0191] HPLC testing was performed using a similar procedure. In a typical immersion experiment, the anodic and cathode solutions were mixed separately to obtain solutions containing neutral pH water, NaCl auxiliary electrolyte, and PDI-tetraammonium-Cl4 and ferrocene-diammonium-Cl2, respectively. A portion of these solutions was divided into separate vials, and approximately 50 mg of the test material was then added to each vial. Another 1 mAh of solution was then placed in an H-cell battery with a SelemionAMV membrane and fully charged. After charging, the anodic and cathode solutions were divided into separate vials, and approximately 50 mg of the test material was then added to each vial. Separately, a control solution consisting of neutral pH water and NaCl was placed in a vial, and approximately 50 mg of the test material was added. The solutions were stored in an airless glove box, and sampling was performed continuously on a weekly basis. Small samples were taken from each vial and injected into an HPLC instrument for purity analysis to confirm the chemical compatibility of the test material with the charged anodic solution, charged cathode solution, neutral anodic solution, neutral cathode solution, and control solution. Chromatograms of ferrocene and perylenediimide after 14 weeks of exposure were recorded for analysis.

[0192] Small molecule test. Sodium besylate is a form of sodium aromatic sulfonate salt, Selemion TM This represents the functional groups grafted onto the polystyrene backbone of the AMVN membrane. Adding this in excess allows for determining whether there are inherent stability issues with aryl sulfonates present in or leaching from the membrane. Sodium tosylate has an additional structural motif, a benzyl carbon (methyl group), and functions as a water-soluble test reagent to evaluate the stability of this position, which is known to undergo radical-promoting reactions under certain conditions. Propylene carbonate and sulfolane are non-volatile solvents of interest from the standpoint of viscosity-reducing properties. [Example 8: Synthesis of water-soluble perylenediimide redox active compound] The synthesis procedure for obtaining perylenediimide is described below. [ka]

[0193] PTCDA (2.35 g, 6 mmol) was suspended in dimethylacetamide (20 mL) and stirred. N,N-dimethyldipropylthriamine (1.96 g, 2.22 mL, 12.3 mmol) was added, and the solution was heated to 120°C. The solution was reacted at 120°C for 12 hours, and then cooled to room temperature. The reaction mixture was poured into siRNA (100 mL) and vigorously stirred. The precipitated solid was collected by filtration, washed with siRNA, and dried under high vacuum to obtain the product as a dark purple / red solid (2.5 g, 3.7 mmol, 62%). 1H NMR: (CDCl3, 300MHz) δ1.67(tt, J=7.1Hz, 7.1Hz, 4H), 1.97(tt, J=6.8Hz, 6.8Hz, 4H), 2.21(s, 12H), 2.32(t, J= 7.4Hz, 4H), 2.71(dt, J=18.2Hz, 7Hz, 8H), 4.23(t, J=6.8Hz, 4H), 8.13(d, J=7.2Hz, 4H), 8.35(d, J=7.8Hz, 4H). [ka]

[0194] Tetraamine PDI (1.35 g, 2 mmol) and potassium carbonate (0.829 g, 6 mmol) were suspended in methanol (20 mL). Methyl tosylate (4.47 g, 3.62 mL, 24 mmol) was added, and the reaction mixture was heated overnight at 55°C. The reaction mixture was cooled to room temperature, diluted with methanol (20 mL), and filtered to remove the white solid. The filtrate was concentrated to dryness using a rotary vacuum evaporator and dissolved in the minimum amount of methanol. Upon addition of acetone, a red solid precipitated from the solution. The solid was isolated by filtration and vacuum-dried at 55°C to obtain a dark red solid (2.05 g, 1.41 mmol, 71%). ¹H NMR: (D₂O, 300 MHz) δ 2.17(s, ¹²H, OTs) -), 2.43-2.25(m, 8H), 3.14(s, 18H), 3.22(s, 12H), 3.38(m, 4H), 3.47(m, 4H) ), 3.62(m, 4H), 4.12(m, 4H), 7.29-7.10(bs, 4H), 7.17(d, J=8.2Hz, 8H, OTs - ), 7.51(d, J=8.2Hz, 8H, OTs - ), 7.69 (bs, 4H). [ka]

[0195] Tetraammonium tosylate PDI (2.90 g, 2 mmol) was dissolved in concentrated HCl (20 mL). The resulting mixture was heated at 85°C for 24 hours. The reaction mixture was cooled to room temperature and diluted with isopropanol (60 mL) while vigorously stirring. The precipitated solid was collected by filtration, washed with isopropanol, and then vacuum-dried at 70°C to obtain the product as a red / black solid (1.6 g, 1.77 mmol, 88%). ¹H NMR: (D₂O, 300 MHz) δ 2.71-2.12 (bm, 8H), 3.90-2.99 (bm, 42H), 4.21 (bs, 4H), 8.39-6.96 (bm, 8H). [ka]

[0196] Glutamic acid and PTCDA were suspended in DMSO. Tribasic potassium phosphate was added under stirring, and the solution was heated to 120°C. The reaction mixture was stirred for 18 hours and then cooled to room temperature. 1M HCl was added, and the precipitated solid was filtered to obtain the product as a purple / black solid (100% relative to the recovered starting material). [ka]

[0197] Aspartic acid (2.93 g, 22 mmol) and PTCDA (3.92 g, 10 mmol) were suspended in ethylene glycol. Tribasic potassium phosphate (9.9 g, 46 mmol) was added, and the resulting solution was heated at 140°C for 12 hours. The reaction mixture was cooled to room temperature and poured into 1 M HCl (aqueous solution) (50 mL). The resulting precipitate was collected by filtration, washed with water, and then vacuum-dried at 55°C to obtain the product as a purple solid (1.914 g, 3.07 mmol, 31%). ¹H NMR: (D6-DMSO, 300 MHz) δ 2.85 (dd, J=16.6 Hz, 4.5 Hz, 2H), 3.42 (m, 2H), 6.08-6.01 (m, 2H), 8.43-7.67 (bm, 8H). [Example 9: Synthesis of water-soluble ferrocene-based redox-active compounds] [ka]

[0198] Ferrocene (50 g, 269 mmol, 1.1 equivalents) was added to a 3 L three-necked round-bottom flask equipped with a stirring bar, an addition funnel, and a gas outlet connected to a bubbler filled with saturated water-soluble NaHCO3. The apparatus was purged with dry nitrogen gas. Dichloromethane (600 mL) was added and stirred to dissolve the ferrocene. The mixture was cooled to 0°C in an ice bath. A stirring bar was placed in another round-bottom flask, and aluminum trichloride (35.9 g, 269 mmol, 1.1 equivalents) was added, and the flask was purged with dry nitrogen. Dichloromethane (600 mL) was added and stirred to suspend the aluminum trichloride. 4-Chlorobutyryl chloride (34.4 g, 245.5 mmol, 1.0 equivalent) was added dropwise to the aluminum trichloride suspension and stirred until the dissolution of aluminum trichloride stopped. The acid chloride mixture was decanted from undissolved aluminum trichloride into the addition funnel of the reaction apparatus. This solution was slowly added to the ferrocene solution in the reaction vessel at 0°C, taking care to ensure the mixture did not exceed 10°C. The mixture was then stirred for 3 hours while gradually warming the bath to room temperature. The vessel was cooled again to 0°C. In a separate flask, sodium borohydride (18.5 g, 489 mmol, 2.0 equivalents) was combined with digrime (70 mL) and dichloromethane (20 mL) under a nitrogen atmosphere. This mixture was transferred to the addition funnel of the reaction vessel and added dropwise to the reaction mixture. The reaction mixture was stirred at room temperature for 18 hours. 1M ammonium chloride aqueous solution (100 mL), water (100 mL), and saturated potassium sodium tartrate aqueous solution (400 mL) were added sequentially, and the reaction was stopped at 0°C. After gas generation ceased, the organic layer was collected, the aqueous layer was extracted with dichloromethane (3 washes, 100 mL each), the solvent was removed from the combined organic layers, and the resulting liquid was dissolved in 500 mL of hexane. The hexane layer was washed with water (8 washes, 200 mL each) to remove the digrime, and the mixture was dried by shaking over saturated sodium chloride aqueous solution. The organic layer was further dried with solid magnesium sulfate (100 g), filtered, and the solvent was removed to obtain the desired product as an orange oily substance (60 g, 88%). 1¹H NMR (300 MHz, chloroform-d) δ (ppm) 4.11 (overlap, 9H), 3.58 (t, J=7.0 Hz, 2H), 2.40 (t, J=7.8 Hz, 2H), 1.84 (dt, J=6.8, 7.8, 2H), 1.71 (dt, J=6.8, 7.0, 2H). [ka]

[0199] 4-chlorobutylferrocene (75 g, 276.6 mmol, 1.0 equivalent), N,N,N′,N′-tetramethyl-1,3-propanediamine (105 g, 814 mmol, 3 equivalents), and acetonitrile (500 mL) were mixed in a round-bottom flask and heated at 60°C for 12 hours. The mixture was cooled and washed with hexane (5 times, 150 mL each), and the acetonitrile layer was set aside. After removing the combined hexane layer, an orange liquid was obtained. To this liquid, N,N,N′,N′-tetramethyl-1,3-propanediamine (50 g, 388 mmol, 1.43 equivalents) and acetonitrile (250 mL) were added in a round-bottom flask, and the mixture was heated at 60°C for 12 hours. After cooling, the acetonitrile solution was washed with hexane (5 times, 150 mL each), and the acetonitrile layer was combined with the acetonitrile layer set aside in the previous step. The solvent was removed from the combined layers to obtain an orange oily substance. This oily substance was triturated with diethyl ether (200 mL) while sonicating. The ether was decanted, and the residual solvent was further removed under vacuum to obtain the product as a very viscous orange oily substance (97 g, 88%). ¹H NMR (300 MHz, chloroform-d) δ (ppm) 4.08 (overlap, 9H), 3.53 (overlap, 4H), 3.40 (s, 6H), 2.44 (t, J=7.9, 2H), 2.36 (t, J=6.0, 2H), 2.19 (s, 6H), 1.83 (m, 2H), 1.70 (m, 2H), 1.58 (m, 2H). [ka]

[0200] N-[3-(dimethylamino)propyl]-N,N-dimethylferrocenylbutaniminium chloride (97 g, 238 mmol, 1.0 equivalent) was dissolved in methanol (1000 mL). Iodomethane (101 g, 715.3 mmol, 3.0 equivalents) was slowly added using a syringe, and the mixture was stirred at room temperature for 12 hours. The solvent and unreacted iodomethane were removed under reduced pressure, and the residue was dissolved in water (200 mL). After stirring for 1 hour with Amberlite IRA-400 ion exchange resin beads (200 cm³), the resin was filtered off, and this solution was passed through an Amberlite IRA-400 ion exchange resin bead (500 cm³) column, with water used as the eluent. Water was removed from the resulting solution to obtain the product as a very viscous orange oily substance. This product crystallized when left standing (94.4g, 87%). ¹H NMR (300MHz, heavy water) δ (ppm) 4.20 (overlap 9H), 3.34 (overlap, 6H), 3.16 (s, 9H), 3.09 (s, 6H), 2.42 (t, J=7.0, 2H), 2.27 (m, 2H), 1.76 (m, 2H), 1.55 (m, 2H). [ka]

[0201] Ferrocene (10.0 g, 53.4 mmol, 1.00 equivalent) was added to a 1 L three-necked round-bottom flask equipped with a stirring bar, an addition funnel, a reflux condenser, and a gas outlet connected to a bubbler filled with saturated aqueous solution NaHCO3. The apparatus was purged with dry nitrogen gas. Dichloromethane (100 mL) was added and stirred to dissolve the ferrocene. The mixture was cooled to 0°C in an ice bath. A stirring bar was placed in another round-bottom flask, and aluminum trichloride (18.0 g, 134 mmol, 2.50 equivalent) was added, and the flask was purged with dry nitrogen. Dichloromethane (100 mL) was added and stirred to suspend the aluminum trichloride. 3-Chloropropionyl chloride (17.0 g, 134 mmol, 2.50 equivalent) was added dropwise to the aluminum trichloride suspension and stirred until the dissolution of aluminum trichloride stopped. The acid chloride mixture was decanted from undissolved aluminum trichloride into the reaction apparatus's addition funnel. This solution was slowly added to the ferrocene solution at 0°C, taking care to ensure the mixture did not exceed 10°C. The mixture was then refluxed for 16 hours. The vessel was cooled again to 0°C. In a separate flask, sodium borohydride (8.00 g, 214 mmol, 4.00 equivalents) was combined with digrimé (40 mL) and dichloromethane (20 mL) under a nitrogen atmosphere. This mixture was transferred to the addition funnel of the reaction vessel and added dropwise to the reaction mixture. The reaction mixture was stirred at room temperature for 18 hours. 100 mL of 1 M ammonium chloride aqueous solution, 100 mL of water, and 100 mL of saturated potassium sodium tartrate aqueous solution were added sequentially, and the reaction was stopped at 0°C. After gas generation ceased, the organic layer was collected, the aqueous layer was extracted with dichloromethane (3 washes, 50 mL each), the solvent was removed from the combined organic layers, and the resulting liquid was dissolved in 200 mL of hexane. The hexane layer was washed with water (8 washes, 200 mL each) to remove the digrime, and the mixture was dried by shaking over saturated sodium chloride aqueous solution. The organic layer was further dried with solid magnesium sulfate (50 g), filtered, and the solvent was removed to obtain the desired product X as an orange oily substance (13 g, 72%). 1H NMR (300 MHz, chloroform-d) δ (ppm) 4.10 (overlap, 8H), 3.58 (t, J=6.2 Hz, 4H), 2.50 (t, J=7.1 Hz, 4H), 1.98 (tt, J=6.2 Hz, 7.1 Hz, 4H). [ka]

[0202] 1,1′-Bis(3-chloropropyl)ferrocene (1.5 g, 4.4 mmol, 1.0 equivalent), potassium sulfite (8.4 g, 53 mmol, 12 equivalents), and water (100 mL) were added to a 250 mL round-bottom flask equipped with a condenser. The mixture was heated under reflux for 4 days. During this time, the immiscible ferrocene starting material gradually disappeared while being converted to a water-soluble product. The mixture was cooled and extracted with ethyl acetate (washed 3 times, 200 mL) to remove the starting material. Water was removed from the aqueous layer and methanol (100 mL) was added. This mixture was filtered, and methanol was removed by distillation. The resulting yellow solid was washed with a large amount of isopropanol to remove acetate. After drying, the product was obtained as a yellow powder (1.2 g, 54%). 1H NMR (300MHz, heavy water) δ (ppm) 4.06 (overlap, 8H), 2.84 (t, J=7.8Hz, 4H), 2.40 (t, J=7.6Hz, 4H), 1.98 (tt, J=7.8Hz, 7.6Hz, 4H). [ka]

[0203] Ferrocenebutanecarboxylic acid (1.00 g, 3.67 mmol) and N-hydroxysuccinimide (0.423 g, 3.67 mmol) were dissolved in DCM (18.5 mL), and the resulting mixture was stirred at room temperature. EDC (0.733 g, 4.04 mmol) was added, and the mixture was stirred overnight at room temperature. Triethylamine (2.02 g, 2.78 mL, 20 mmol) was added to a solution of glutamic acid (1.08 g, 7.3 mmol) dissolved in isopropanol (10 mL). After dissolving the glutamic acid, a crude solution of ferrocene N-hydroxysuccinimide activated ester was added to the glutamic acid mixture. The resulting mixture was stirred at room temperature for 12 hours, and then heated at 90°C for 12 hours. The reaction of the reaction mixture was stopped by adding 1 M NaOH, and washed with ethyl acetate. The aqueous layer was acidified with 1 M HCl and extracted with ethyl acetate. The ethyl acetate layer was washed with 0.01 M NaOH, and the aqueous washing solution was discarded. The organic layer was then extracted in two parts with 0.1 M NaOH. The aqueous extracts were combined, acidified with 1 M HCl, and extracted with siRNA. The organic extract was washed with water and saline solution, dried over magnesium sulfate, filtered, and concentrated to obtain the product as a yellow solid (0.200 g, 0.5 mmol, 14%). 1H NMR: (d-DMSO, 300MHz) δ1.83-1.63(m, 4H), 2.03-1.90(m, 1H), 2.14(t, J=7.2Hz, 2H), 2.32-2.23(m, 4H), 4 .05-4.01(m, 1H), 4.08(d, J=1.3Hz, 2H), 4.1(s, 5H), 4.21(dt, J=8.5Hz, 5.0Hz, 1H), 8.08(d, J=7.5Hz, 1H). [ka]

[0204] Synthesis of N-(4-ferrocenylbutanoyl)-L-glutamic acid. 4-ferrocenylbutanoic acid (68.0 g, 250 mmol, 1.0 equivalent), DCM (125 mL), and a stirring bar were placed in a 1 L round-bottom flask. Under positive pressure of N2 (g), oxalyl chloride (23.6 mL, 275 mmol, 23.6 mL, 1.20 equivalents) was slowly added dropwise while vigorously stirring, taking care to avoid gas generation. The dark brown solution was stirred at 25°C until gas generation slowed down (approximately 5 minutes). The reaction mixture was then heated further to 40°C and reacted for 1 hour. The solvent was removed using a rotary vacuum evaporator.

[0205] A solution of L-sodium glutamate monohydrate (143 g, 763 mmol, 3.05 equivalents), sodium hydroxide (30.0 g, 750 mol, 3.0 equivalents), and water (68 mL) was prepared at 100°C. Once all solids were dissolved, the pre-prepared ferrocenoate chloride was quickly added to the glutamate solution while stirring. The formation of a brown precipitate was observed during the addition of the acid chloride. Approximately 50 mL of additional water was added to facilitate stirring of the reaction mixture. The reaction mixture was reacted at 100°C for approximately 5 minutes. The reaction mixture was cooled to room temperature, and water was added to completely dissolve all solids. NaCl (solid) was added to completely saturate the aqueous solution. The resulting aqueous solution was titrated with HCl (6 M) to pH 5.8. Impurities were extracted with MeCN (4 × 200 mL). The resulting aqueous layer was further titrated with HCl (6 M) to pH 3. The product was extracted from the aqueous layer using MeCN, and this process was repeated until the resulting aqueous layer turned blue (3 × approximately 200 mL). Approximately 200 mL of silica and approximately 200 mL of anhydrous sodium sulfate were added to the acetonitrile solution. The acetonitrile suspension was stirred at room temperature for 30 minutes. The suspension was filtered through a frit glass filter, and the acetonitrile solution was recovered. The dark red solution was concentrated using a rotary vacuum evaporator. The resulting dark red oily substance was further concentrated under vacuum to obtain a dark yellowish-brown solid (53.8 g, 113 mmol, yield 45%, purity 84%). [ka]

[0206] Synthesis of N-butanoyl-4-ferrocenyliminodiacetic acid. Ferrocene butyric acid (10 g, 0.037 mol) was dissolved in DCM (50 mL), and a few drops of DMF were added. Oxalil chloride (5.13 g, 3.47 mL, 0.40 mol) was added dropwise over 5 minutes, and the resulting mixture was stirred for 45 minutes. The solvent was removed using a rotary vacuum evaporator to obtain the product as a red oily substance. A solution of iminodiacetic acid (9.78 g, 0.074 mol) in 6 M NaOH (24 mL) was diluted with acetone (12 mL). The solution was diluted with water (30 mL) until the mixture was homogeneous. The iminodiacetic acid solution and the solvent-free acid chloride were simultaneously passed through a static mixer, and the resulting reaction mixture was stirred for 20 minutes. The reaction mixture was diluted to 150 mL. The pH was adjusted to 4.9 with 2 M HCl, and the solution was extracted in two parts using DCM. The organic layer was discarded. The aqueous layer was adjusted to pH 2.8 with 6 M HCl, and the solid was precipitated while vigorously stirring. The solid was recovered by filtration and washed twice more with water, 0.1 M HCl, and water. The solid was dried to obtain the product as a grayish-yellow solid (7.74 g, 0.02 mol, 54%).

[0207] 1H NMR: (d-DMSO, 500MHz) δ1.72-1.65(m, 2H), 2.29-2.24(m, 4H), 3.96(s, 1H), 4.03(t, J=1.75Hz, 2H), 4.075(t, J=1.8Hz, 1H), 4.11(s, 5H), 4.1(s, 5H), 4.14-4.12(bs, 2H). [Example 10: H-cell experiment demonstrating the stability of anionic water-soluble perylenediimide and ferrocene electrolyte solution]

[0208] These experiments demonstrate that the disclosed anionic electrolyte solution is compatible in both charged and uncharged states. This static cell experiment setup allows for accurate measurement of Coulomb efficiency for analyzing the electrochemical and physical compatibility between the charged electrolyte solution and the cell manufacturing material. High Coulomb efficiency indicates that electrons introduced into the organic charge storage electrolyte during charging are returned during discharge; that is, the electrolyte does not react electrochemically or physically with anything, including the cell manufacturing material, in the charged state, and thus no charge is lost.

[0209] An exemplary 1 mAh H cell was prepared using glutamate PDI as the anodic solution half-cell and bis-propylsulfonate ferrocene as the cathode solution half-cell. The structures of these molecules are shown below. Figure 9 shows the cycles of glutamate-PDI and bis-propylsulfonate ferrocene. The cell was made of glass and the membrane was Selemion. TM CMV was used. Each half-cell was mixed with a PTFE stirrer, and the electrodes were carbon felt. Coulomb efficiency was measured over a series of cycles. From 10 to 40 cycles, the average Coulomb efficiency exceeded 99.9%, indicating that both the anode and cathode electrolyte solutions were stable. That is, electrochemical or physical degradation was minimal in the charged state. The capacity also remained stable. [ka] [ka]

[0210] An exemplary 1 mAh H cell was prepared using glutamate PDI as the anodic solution half-cell and glutamate amide ferrocene as the cathode solution half-cell. The structures of these molecules are shown below. Figure 10 shows the cycle of glutamate-PDI and bis-propylsulfonate ferrocene. The cell was made of glass and the membrane was Selemion. TMCMV was used. Each half-cell was mixed with a PTFE stirrer, and the electrodes were carbon felt. Coulomb efficiency was measured over a series of cycles. From 10 to 40 cycles, the average Coulomb efficiency exceeded 99.9%, indicating that both the anode and cathode electrolyte solutions were stable. That is, electrochemical or physical degradation was minimal in the charged state. The capacity also remained stable. [ka] [ka] [Examples]

[0211] Example 1: A redox flow battery comprising: a first half-cell containing a first aqueous solution comprising a first electrode and an anode liquid, the anode liquid comprising a perylenediimide compound; a second half-cell containing a second aqueous solution comprising a second electrode and a cathode liquid; and a separator interposed between the first half-cell and the second half-cell, wherein the inner surface of the first half-cell in contact with the first aqueous solution and the inner surface of the second half-cell in contact with the second aqueous solution comprise one or more non-highly chemical-resistant materials.

[0212] Example 2: The redox flow battery according to Example 1, wherein the non-fluorinated polymer is selected from the group consisting of polyolefins, polyethers, polyketones, polyamides, polyureas, natural rubber, and combinations thereof.

[0213] Example 3: The redox flow battery according to Example 1 or Example 2, wherein the non-fluorinated polymer is a copolymer of two or more polymers selected from the group consisting of polyolefins, polyethers, polyketones, polyamides, polyureas, and natural rubber.

[0214] Example 4: A redox flow battery according to any one of Examples 1 to 3, wherein the non-fluorinated polymer is selected from the group consisting of ethylene propylene diene monomer rubber (EPDM), polychloroprene (neoprene), polyamide (nylon), polyether ether ketone (PEEK), polyoxymethylene (POM), polyvinyl chloride (PVC), sodium benzenesulfonate (sodium besylate), sodium 4-toluenesulfonate (sodium tosylate), propylene carbonate, sulfolane, acrylonitrile butadiene rubber (BUNA-N), natural latex rubber, polyethylene (PE), polymethyl methacrylate (PMMA), polypropylene (PP), polyurethane (PUR), EPDM polypropylene matrix elastomer (santoprene), and combinations thereof.

[0215] Example 5: A redox flow battery according to any one of Examples 1 to 4, wherein the non-fluorinated polymer is a copolymer of two or more polymers selected from the group consisting of ethylene propylene diene monomer rubber (EPDM), polychloroprene (neoprene), polyamide (nylon), polyether ether ketone (PEEK), polyoxymethylene (POM), polyvinyl chloride (PVC), sodium benzenesulfonate (sodium besylate), sodium 4-toluenesulfonate (sodium tosylate), propylene carbonate, sulfolane, acrylonitrile butadiene rubber (BUNA-N), natural latex rubber, polyethylene (PE), polymethyl methacrylate (PMMA), polypropylene (PP), polyurethane (PUR), and EPDM polypropylene matrix elastomer (santoprene).

[0216] Example 6: A redox flow battery according to any one of Examples 1 to 5, wherein the first half-cell includes a first electrode plate, the second half-cell includes a second electrode plate, and the first electrode plate includes a composite material of graphite and polymer.

[0217] Example 7: A redox flow battery according to any one of Examples 1 to 6, wherein the composite material is resin-filled graphite or graphite in a thermosetting resin matrix.

[0218] Example 8: A redox flow battery according to any one of Examples 1 to 7, wherein the polymer of the composite material is polyethylene or polypropylene.

[0219] Example 9: A redox flow battery according to any one of Examples 1 to 8, further comprising a gasket for separating the reaction vessel from the first electrode plate, wherein the gasket comprises a non-high chemical-resistant elastomer material, the non-high chemical-resistant elastomer material being selected from the group consisting of ethylene propylene diene monomer rubber (EPDM), polychloroprene (neoprene), polyamide (nylon), polyether ether ketone (PEEK), polyoxymethylene (POM), polyvinyl chloride (PVC), sodium benzenesulfonate (sodium besylate), sodium 4-toluenesulfonate (sodium tosylate), propylene carbonate, sulfolane, acrylonitrile butadiene rubber (BUNA-N), natural latex rubber, polyethylene (PE), polymethyl methacrylate (PMMA), polypropylene (PP), polyurethane (PUR), EPDM polypropylene matrix elastomer (santoprene), and combinations thereof.

[0220] Example 10: A redox flow battery according to any one of Examples 1 to 9, wherein the separator includes a polystyrene-based ion exchange membrane.

[0221] Example 11: A redox flow battery according to any one of Examples 1 to 10, further comprising a supply line positioned outside the first half-cell and supplying an anode liquid to the first half-cell, wherein the supply line comprises a non-highly chemical-resistant elastomer material, the non-highly chemical-resistant elastomer material being selected from the group consisting of ethylene propylene diene monomer rubber (EPDM), polychloroprene (neoprene), polyamide (nylon), polyether ether ketone (PEEK), polyoxymethylene (POM), polyvinyl chloride (PVC), sodium benzenesulfonate (sodium besylate), sodium 4-toluenesulfonate (sodium tosylate), propylene carbonate, sulfolane, acrylonitrile butadiene rubber (BUNA-N), natural latex rubber, polyethylene (PE), polymethyl methacrylate (PMMA), polypropylene (PP), polyurethane (PUR), EPDM polypropylene matrix elastomer (santoprene), and combinations thereof.

[0222] Example 12: Perylenediimide compounds are of formula (I) [ka] or having a salt thereof, T is -(LG) n -X is, T' represents H, (C1-C6) alkyl, or -(LG) n -X is, L is a -(C2-C5)-alkyl group, optionally substituted with OH, OCH3, or halogen. [ka] And, Each X is independently H, -(C1-C 10 ) alkyl, -(C2-C6)alkenyl, -(C2-C6)alkynyl, and -(C1-C6)alkoxy, each of which is unsubstituted or independently selected with 1, 2, or 3 R 1 It is substituted with the base, Each R1 These are independently -OH, -O(C1-C6)-alkyl, -O(C1-C6)-alkyl-O(C1-C6)-alkyl, -O(C1-C6)-alkyl-O(C1-C6)-alkyl-O(C1-C6)alkyl, -[O(C1-C6)-alkyl] p -O(C1-C6), -O(C=O)(C1-C6)alkyl, -O(C=O)O(C1-C6)alkyl, -O(C=O)OH, -O(C=O)NH2, -O(C=O)NH(C1-C6)alkyl, O(C=O)N[(C1-C6)alkyl]2, -NH(C=O)(C1-C6)alkyl, N(C1-C6)alkyl(C=O)(C1-C6)alkyl, halogen, -CN, -NO2, NH2, NH(C1-C6)alkyl, and N[(C1-C6)alkyl]2. n=2 to 8, A redox flow battery according to any one of Examples 1 to 11, wherein p = 3 to 20.

[0223] Example 13: T and T' independently -(LG) n -X, a redox flow battery according to any one of Examples 1 to 12.

[0224] Example 14: A redox flow battery according to any one of Examples 1 to 13, wherein L is selected from the group consisting of unsubstituted -(C2-C5)-alkyl, ethyl, and propyl.

[0225] Example 15: A redox flow battery according to any one of Examples 1 to 14, wherein n is 2, 3, or 4.

[0226] Example 16:G is, [ka] And, A redox flow battery according to any one of Examples 1 to 15, wherein X is H, methyl, -CH2CH2OH, or -(C1-C6)-alkyl.

[0227] Example 17: The compound of formula (I) is [ka] , [ka] , [ka] , [ka] , [ka] [ka] The redox flow battery described in any one of Examples 1 to 16.

[0228] Example 18: Perylenediimide compound is of formula (II) [ka] It has, Each Y is independently -O-, -S-, or -NH-. Each q is independently between 1 and 8. Each X is independently H, -(C1-C 10 )-alkyl, -(C2-C6)alkenyl, -(C2-C6)alkynyl, and -(C1-C6)alkoxy, each of which is unsubstituted or independently selected with 1, 2, or 3 R 1 It is substituted with the base, Each R 1 These are independently -OH, -O(C1-C6)-alkyl, -O(C1-C6)-alkyl-O(C1-C6)-alkyl, -O(C1-C6)-alkyl-O(C1-C6)-alkyl-O(C1-C6)alkyl, -[O(C1-C6)-alkyl] p-O(C1-C6), -O(C=O)(C1-C6)alkyl, -O(C=O)O(C1-C6)alkyl, -O(C=O)OH, -O(C=O)NH2, -O(C=O)NH(C1-C6)alkyl, O(C=O)N[(C1-C6)alkyl]2, -NH(C=O)(C1-C6)alkyl, N(C1-C6)alkyl(C=O)(C1-C6)alkyl, halogen, -CN, -NO2, NH2, NH(C1-C6)alkyl, and N[(C1-C6)alkyl]2. A redox flow battery according to any one of Examples 1 to 17, wherein each V is a counterion.

[0229] Example 19: Perylenediimide compound is of formula (III) [ka] It has, Each X is independently H, -(C1-C 10 )-alkyl, -(C2-C6)alkenyl, -(C2-C6)alkynyl, and -(C1-C6)alkoxy, each of which is unsubstituted or independently selected with 1, 2, or 3 R 1 It is substituted with the base, Each R 1 These are independently -OH, -O(C1-C6)-alkyl, -O(C1-C6)-alkyl-O(C1-C6)-alkyl, -O(C1-C6)-alkyl-O(C1-C6)-alkyl-O(C1-C6)alkyl, -[O(C1-C6)-alkyl] p -O(C1-C6), -O(C=O)(C1-C6)alkyl, -O(C=O)O(C1-C6)alkyl, -O(C=O)OH, -O(C=O)NH2, -O(C=O)NH(C1-C6)alkyl, O(C=O)N[(C1-C6)alkyl]2, -NH(C=O)(C1-C6)alkyl, N(C1-C6)alkyl(C=O)(C1-C6)alkyl, halogen, -CN, -NO2, NH2, NH(C1-C6)alkyl, and N[(C1-C6)alkyl]2. Each s is independently between 2 and 4. Each R is independently H, -CH2OH, -CH2CH2OH, -CH2CH2OCH2CH2OH, or -CH2CH2OCH2CH2O(C1-6)alkyl. Each V - A redox flow battery according to any one of Examples 1 to 18, wherein is a counterion.

[0230] Example 20: The compound of formula (III) is [ka] [ka] The redox flow battery described in any one of Examples 1 to 19.

[0231] Example 21: Perylenediimide compound is of formula (IV) [ka] It has, R is [ka] [ka] [ka] The redox flow battery described in any one of Examples 1 to 20.

[0232] Example 22: Perylenediimide compound is of formula (V) [ka] or having a salt thereof, L is -(C1-C6)-alkyl, Each G is [ka] And, A is a positive ion, A redox flow battery according to any one of Examples 1 to 21, wherein n=1 to 5.

[0233] Example 23: A redox flow battery according to any one of Examples 1 to 22, wherein L is substituted with OH, OCH3, and halogen, and each A is lithium, sodium, potassium, or ammonium.

[0234] Example 24: LG n The base is a redox flow battery according to any one of Examples 1 to 23, having at least one chiral center.

[0235] Example 25: The compound of formula (V) is [ka] [ka] [ka] A redox flow battery according to any one of Examples 1 to 24, selected from the group consisting of the following.

[0236] Example 26: A redox flow battery according to any one of Examples 1 to 25, wherein A is lithium, sodium, potassium, or ammonium.

[0237] Example 27: The cathode liquid contains a second compound having a ferrocene moiety, and the second compound is [ka] [ka] [ka] , [ka] [ka] [ka] [ka] [ka] [ka] [ka] A redox flow battery according to any one of Examples 1 to 26, having a formula selected from the group consisting of the following.

[0238] Example 28: The cathode liquid contains a second compound having a ferrocene moiety, the second compound being of formula (VI) [ka] It has, L is -(C1-C 10 )-alkyl, -(C1-C6)-alkenyl, -(C1-C6)-alkynyl, -(C1-C6)-alkyl-O(C1-C6)-alkyl, -(C1-C6)-alkyl-O-(C=O)-(C1-C6)alkyl, -(C1-C6)-alkyl-(C=O)-O-(C1-C6)alkyl, -(C1-C6)alkyl-NH-(C=O)(C1-C6)alkyl, -(C1-C6)alkyl-NR 2-(C=O)(C1-C6)alkyl, -(C1-C6)alkyl-(C=O)-NH-(C1-C6)alkyl, -(C1-C6)alkyl-(C=O)-NR 2 -(C1-C6)alkyl, or -(C1-C 10 A redox flow battery according to any one of Examples 1 to 27, wherein the battery is an alkyl-aryl battery.

[0239] Here, L' is -H, -(C1-C 10 )-alkyl, -(C1-C6)-alkenyl, -(C1-C6)-alkynyl, -(C1-C6)-alkyl-O(C1-C6)-alkyl, -(C1-C6)-alkyl-O-(C=O)-(C1-C6)alkyl, -(C1-C6)-alkyl-(C=O)-O-(C1-C6)alkyl, -(C1-C6)alkyl-NH-(C=O)(C1-C6)alkyl, -(C1-C6)alkyl-NR 2 -(C=O)(C1-C6)alkyl, -(C1-C6)alkyl-(C=O)-NH-(C1-C6)alkyl, -(C1-C6)alkyl-(C=O)-NR 2 -(C1-C6)alkyl, or -(C1-C 10 )-alkyl-aryl, G is [ka] Selected from the group consisting of, G is 2 or greater, A is Li, K, Na, or NH4. R 2 is, -(C1-C 10 )-alkyl, -(C1-C6)-alkenyl, -(C1-C6)-alkynyl, -(C1-C 10 It is an alkyl-aryl, -aryl, or -(C=O)-(C1-C6)-alkyl.

[0240] Example 29: L is substituted with at least one group selected from the group consisting of G, -OH, -OCH3, and -halogen, L' is substituted with at least one group selected from the group consisting of G, -OH, -OCH3, and -halogen, R 2 A redox flow battery according to any one of Examples 1 to 28, wherein at least one G is replaced.

[0241] Example 30: The compound of formula (VI) is [ka] [ka] [ka] [ka] The redox flow battery described in any one of Examples 1 to 29. [The doctrine of equivalence]

[0242] As can be inferred from the above discussion, the above-mentioned concepts can be implemented in various configurations according to the embodiments of the present invention. Therefore, although the present invention has been described in specific embodiments, many additional modifications and variations will be apparent to those skilled in the art. Accordingly, it should be understood that the present invention can be carried out in ways other than those specifically described. In other words, the embodiments of the present invention are merely illustrative and should not be considered limiting.

[0243] As used herein, the singular terms "a," "an," and "the" may refer to multiple subjects unless otherwise specified. When referring to a subject in the singular form, unless explicitly stated otherwise, it should be understood to mean "one or more" rather than "a single" subject.

[0244] As used herein, the terms “approximately” and “about” are used to describe and account for small variations. When used with an event or situation, these terms may refer to both instances where the event or situation occurs exactly and instances where it occurs approximately. When used with a number, these terms may refer to a range of variation of that number of ±10% or less, for example, ±5%, ±4%, ±3%, ±2%, ±1%, ±0.5%, ±0.1%, or ±0.05%.

[0245] In addition, quantities, ratios, and other numerical values ​​may be presented in range form in this specification. Such range forms are used for convenience and conciseness and should be flexibly understood to include not only the numerical values ​​explicitly designated as limits of the range, but also all individual numerical values ​​or subranges contained within that range, as if each numerical value and subrange were explicitly defined. For example, a ratio expressed in the range of about 1 to about 200 should be understood to include not only the explicitly listed limits of about 1 and about 200, but also individual ratios such as about 2, about 3, and about 4, as well as subranges such as about 10 to about 50 and about 20 to about 100.

Claims

1. Redox flow batteries including the following: A first-phase cell comprising a first electrode and a first aqueous solution containing an anode, wherein the anode contains a perylenediimide compound. The device includes a second electrode, a second aqueous solution containing a cathode solution, and a separator interposed between the first and second half-cells. Here, the inner surfaces of the first half-cell in contact with the first aqueous solution and the second half-cell in contact with the second aqueous solution include one or more non-high chemical-resistant materials.

2. The redox flow battery according to claim 1, wherein the non-fluorinated polymer is selected from the group consisting of polyolefins, polyethers, polyketones, polyamides, polyureas, natural rubber, and combinations thereof.

3. The redox flow battery according to claim 1, wherein the non-fluorinated polymer is a copolymer of two or more polymers selected from the group consisting of polyolefins, polyethers, polyketones, polyamides, polyureas, and natural rubber.

4. The redox flow battery according to claim 1, wherein the non-fluorinated polymer is selected from the group consisting of ethylene propylene diene monomer rubber (EPDM), polychloroprene (Neoprene), polyamide (nylon), polyether ether ketone (PEEK), polyoxymethylene (POM), polyvinyl chloride (PVC), sodium benzenesulfonate (sodium besylate), sodium 4-toluenesulfonate (sodium tosylate), propylene carbonate, sulfolane, acrylonitrile butadiene rubber (BUNA-N), natural latex rubber, polyethylene (PE), polymethyl methacrylate (PMMA), polypropylene (PP), polyurethane (PUR), EPDM polypropylene matrix elastomer (Santoprene), and combinations thereof.

5. The redox flow battery according to claim 1, wherein the non-fluorinated polymer is a copolymer of two or more polymers selected from the group consisting of ethylene propylene diene monomer rubber (EPDM), polychloroprene (Neoprene), polyamide (nylon), polyether ether ketone (PEEK), polyoxymethylene (POM), polyvinyl chloride (PVC), sodium benzenesulfonate (sodium besylate), sodium 4-toluenesulfonate (sodium tosylate), propylene carbonate, sulfolane, acrylonitrile butadiene rubber (BUNA-N), natural latex rubber, polyethylene (PE), polymethyl methacrylate (PMMA), polypropylene (PP), polyurethane (PUR), and EPDM polypropylene matrix elastomer (Santoprene).

6. The redox flow battery according to claim 1, wherein the first half-cell comprises a first bipolar plate, the second half-cell comprises a second bipolar plate, and the first bipolar plate comprises a composite material of graphite and polymer.

7. The redox flow battery according to claim 6, wherein the composite material is resin-filled graphite or graphite in a thermosetting resin matrix.

8. The redox flow battery according to claim 6, wherein the polymer of the composite material is polyethylene or polypropylene.

9. The redox flow battery according to claim 1, further comprising a gasket for separating the reaction vessel from the first bipolar plate, wherein the gasket comprises a non-high chemical-resistant elastomer material, the non-high chemical-resistant elastomer material being selected from the group consisting of ethylene propylene diene monomer rubber (EPDM), polychloroprene (Neoprene), polyamide (nylon), polyether ether ketone (PEEK), polyoxymethylene (POM), polyvinyl chloride (PVC), sodium dodecylbenzenesulfonate (sodium besylate), sodium 4-toluenesulfonate (sodium tosylate), propylene carbonate, sulfolane, acrylonitrile butadiene rubber (BUNA-N), natural latex rubber, polyethylene (PE), polymethyl methacrylate (PMMA), polypropylene (PP), polyurethane (PUR), EPDM polypropylene matrix elastomer (Santoprene), and combinations thereof.

10. The redox flow battery according to claim 1, wherein the separator includes a polystyrene-based ion exchange membrane.

11. A redox flow battery according to claim 1, further comprising a supply line positioned outside the first half of the battery for supplying anode liquid to the first half of the battery, wherein the supply line comprises a non-chemical-resistant elastomer material, the non-chemical-resistant elastomer material being selected from the group consisting of ethylene propylene diene monomer rubber (EPDM), polychloroprene (Neoprene), polyamide (Nylon), polyether ether ketone (PEEK), polyoxymethylene (POM), polyvinyl chloride (PVC), sodium benzenesulfonate (sodium besylate), sodium 4-toluenesulfonate (sodium tosylate), propylene carbonate, sulfolane, acrylonitrile butadiene rubber (BUNA-N), natural latex rubber, polyethylene (PE), polymethyl methacrylate (PMMA), polypropylene (PP), polyurethane (PUR), EPDM polypropylene matrix elastomer (Santoprene), and combinations thereof.

12. The redox flow battery according to claim 1, wherein the perylenediimide compound has formula (I). [Case 1] Examples include salts thereof. T is -(LG)n -X T' is H, (C1-C6) alkyl, or -(LG)n-X L is -(C2-C5)-alkyl and can be optionally substituted with OH, OCH3, or a halo. Each X is independently H, -(C1-C10)alkyl, -(C2-C6)alkyl, -(C2-C6)alkyl, and -(C1-C6)alkoxy group, each substituted with one, two, or three independently selected R1 groups; Each R1 is OH, C1-C6-O(, -O(C=O)OH, -O(C=O)NH2, -O(C=O)NH(C1-C6))-alkyl, -O(, -CN, -NO2, NH2, NH(C1-C6))-alkyl, -O(C1-C6)-alkyl, -O(C1-C6)-alkyl-O(C1-C6)-alkyl, -O(C1-C6)-alkyl, -[O(C1-C6)-alkyl)-alkyl, -O(C1-C6)-alkyl, -O(C1-C6)-alkyl-alkyl, -O(p-O(C1-C6), -O(C=O)(C1-C6))-alkyl, -O(OOI)-alkyl, , -O(C=O)O(C1-C6)alkyl, O(, -CN, -NO2, NH2, NH(C1-C6))N[(C1-C6)alkyl]2, -NH(C=O)(C1-C6), N(C1-C6)alkyl n = 2–8; and p = 3–20.

13. The redox flow battery according to claim 12, wherein T and T' are each independently -(LG)n -X.

14. The redox flow battery according to claim 12, wherein L is selected from the group consisting of unsubstituted-(C2-C5)-alkyl, ethyl, and propyl groups.

15. The redox flow battery according to claim 12, wherein n is 2, 3, or 4.

16. The redox flow battery according to claim 12, wherein G is a methyl group, -CH2CH2OH, or -(C1-C6)-alkyl group.

17. The redox flow battery according to claim 12, wherein the compound of formula (I) is [Case 2]

18. The redox flow battery according to claim 1, wherein the perylenediimide compound has formula (II). [C3] (In the formula, Each Y is independently -O-, -S-, or -NH-. Each q is independently 1 to 8, and each X is independently H, -(C1-C10)-alkyl, -(C2-C6)alkenyl, -(C2-C6)alkynyl, and -(C1-C6)alkoxy group, each unsubstituted or substituted with one, two, or three independently selected R1 groups. Each R1 is independently -OH, -O(C1-C6)-alkyl, -O(C1-C6)-alkyl-O(C1-C6)-alkyl, -O(C1-C6)-alkyl-O(C1-C6)-alkyl-O(C1-C6)alkyl, -[O(C1-C6)-alkyl]alkyl, -O(C=O)O(C1-C6)alkyl, -O(C=O)OH, -O(C=O)NH2, -O(C=O)NH(C1-C6)alkyl, O(C=O)N[(C1-C6)alkyl]2, -NH(C=O)(C1-C6)alkyl, N(C1-C6)alkyl(C=O)(C1-C6)alkyl, halo, -CN, -NO2, NH2, NH(C1-C6)alkyl, and N[(C1-C6)alkyl]p These are -O(C1 -C6) and -O(C=O)(C1 -C6), and in each case, V is the counterion.

19. The redox flow battery according to claim 1, wherein the perylenediimide compound has formula (III). [C4] Note X is independently H, -(C1-C10)-alkyl, -(C2-C6)alkenyl, -(C2-C6)alkynyl, and -(C1-C6)alkoxy, each being unsubstituted or substituted with one, two, or three independently selected R1 groups. Each R1 is OH, C1-C6-O(, -O(C=O)OH, -O(C=O)NH2, -O(C=O)NH(C1-C6))-alkyl, -O(, -CN, -NO2, NH2, NH(C1-C6))-alkyl, -O(C1-C6)-alkyl, -O(C1-C6)-alkyl-O(C1-C6)-alkyl, -O(C1-C6)-alkyl, -[O(C1-C6)-alkyl)-alkyl, -O(C1-C6)-alkyl, -O(C1-C6)-alkyl-alkyl, -O(p-O(C1-C6), -O(C=O)(C1-C6))-alkyl, -O(OOI)-alkyl, , -O(C=O)O(C1-C6)alkyl, O(, -CN, -NO2, NH2, NH(C1-C6))N[(C1-C6)alkyl]2, -NH(C=O)(C1-C6), N(C1-C6)alkyl s is independently 2 to 4. Each R is independently H, -CH2 OH, -CH2 CH2 OH, -CH2 CH2 OCH2 CH2 OH, or -CH2 CH2 OCH2 CH2 O(C1-6) alkyl, and each V- is an antione.

20. The compound according to claim 13, wherein the compound of formula (III) is [C5]

21. The redox flow battery according to claim 1, wherein the perylenediimide compound has formula (IV). [Case 6] (In the formula, R is , , or .

22. The redox flow battery according to claim 1, wherein the perylenediimide compound has formula (V). [Chem.7] Examples include salts thereof. L is -(C1-C6)-alkyl; Each G is; A is a cation, and n=1 to 5.

23. L is OH, OCH 3 , and replaced with a halo; where each A is lithium, sodium, potassium, or ammonium, the redox flow battery according to claim 22.

24. The redox flow battery according to claim 22, wherein the L-Gn group has at least one chiral center.

25. The redox flow battery according to claim 22, wherein the compound of formula (V) is selected from the group consisting of . [Chem.8]

26. A redox flow battery according to claim 25, wherein A is lithium, sodium, potassium, or ammonium.

27. The redox flow battery according to claim 1, wherein the cathode liquid comprises a second compound having a ferrocene portion, and the second compound has a formula selected from the group consisting of . [Chem.9]

28. The redox flow battery according to claim 1, wherein the cathode liquid comprises a second compound having a ferrocene portion, and the second compound has formula (VI). L is -(C1-C10)-alkyl, -(C1-C6)alkylnel, -(C1-C6)-alkylnel, -(C1-C6)-alkyl, C1-C6-O(C1-C6)-alkyl, -(C1-C6)-alkyl-O-(C=O)-(C1-C6)-alkyl, -(C1-C6)-(C=O)-O-(C1-C6)-alkyl, -(C1-C6)alkyl, -(alkyl)alkyl, -(C1-C6)alkyl-NR2-(C=O)(C1-C6)alkyl, -(-NR2-(C=O)(C1-C6))alkyl-(C=O)-NH-(C1-C6), -(C1-C6)alkyl-(C=O)-NR2-(C1-C6), or -(C1-C10)-alkyl-aryl. L' is -H, -(C1-C10)alkyl, -(C1)alkylnel, -(C1-C1)-alkyl, -(C1-C6)-alkyl(C1-C6)-O(C1-C6)alkyl)-alkyl, -(C1-C6)-O-(C=O)-(C1-C6)-alkyl, -(C1-C6)-(C=O)-O-(C1-C6)-alkyl, -(C1-C6)alkyl, -(alkyl)alkyl, -(lkyl--NR2-(C=O)(C1-C6), -(C1-C6)alkyl, -(C1-C6)-(C=O)-NR2-(C1-C6)alkyl, or -(C1-C10)-alkyl-aryl. G is selected from the group consisting of . g is 2 or greater. A is Li, K, Na, or NH4, and R2 is -(C1-C10)-alkyl, -(C1-C6)-alkenyl, -(C1-C6)-alkynyl, -(C1-C10)-alkyl, -aryl, or -(C=O)-(C1-C6)-alkyl.

29. The redox flow battery according to claim 28, wherein L is replaced by at least one group selected from the group consisting of G, -OH, -OCH3, and -halo; L' is replaced by at least one group selected from the group consisting of G, -OH, -OCH3, and -halo; and R2 is replaced by at least one G.

30. The redox flow battery according to claim 28, wherein the compound of formula (VI) is [Chemical formula 10]

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