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Energy Storage

Grid Energy Storage Patents

2018

  • U.S. Patent No. 9,960,443, Issued May. 1, 2018.
    Redox flow batteries having multiple electroactive elements
    Abstract:Introducing multiple redox reactions with a suitable voltage range can improve the energy density of redox flow battery (RFB) systems. One example includes RFB systems utilizing multiple redox pairs in the positive half cell, the negative half cell, or in both. Such RFB systems can have a negative electrolyte, a positive electrolyte, and a membrane between the negative electrolyte and the positive electrolyte, in which at least two electrochemically active elements exist in the negative electrolyte, the positive electrolyte, or both.

2017

  • U.S. Patent No. 9,819,039, Issued Nov. 14, 2017.
    Redox flow batteries based on supporting solutions containing chloride
    Abstract: Redox flow battery systems having a supporting solution that contains Cl ions can exhibit improved performance and characteristics. Furthermore, a supporting solution having mixed SO4 2− and Cl ions can provide increased energy density and improved stability and solubility of one or more of the ionic species in the catholyte and/or anolyte. According to one example, a vanadium-based redox flow battery system is characterized by an anolyte having V2+ and V3+ in a supporting solution and a catholyte having V4+ and V5+ in a supporting solution. The supporting solution can contain Cl ions or a mixture of SO4 2− and Cl ions.
  • U.S. Patent No. 9,793,566, Issued Oct. 17, 2017.
    Aqueous electrolytes for redox flow battery systems
    Abstract: An aqueous redox flow battery system includes an aqueous catholyte and an aqueous anolyte. The aqueous catholyte may comprise (i) an optionally substituted thiourea or a nitroxyl radical compound and (ii) a catholyte aqueous supporting solution. The aqueous anolyte may comprise (i) metal cations or a viologen compound and (ii) an anolyte aqueous supporting solution. The catholyte aqueous supporting solution and the anolyte aqueous supporting solution independently may comprise (i) a proton source, (ii) a halide source, or (iii) a proton source and a halide source.
  • U.S. Patent No. 9,748,595, Issued Aug. 29, 2017.
    High-energy-density, aqueous, metal-polyiodide redox flow batteries
    Abstract: Improved metal-based redox flow batteries (RFBs) can utilize a metal and a divalent cation of the metal (M2+) as an active redox couple for a first electrode and electrolyte, respectively, in a first half-cell. For example, the metal can be Zn. The RFBs can also utilize a second electrolyte having I, anions of Ix (for x≧3), or both in an aqueous solution, wherein the I and the anions of Ix (for x≧3) compose an active redox couple in a second half-cell.

2016

  • U.S. Patent No. 9,525,191, Issued Dec. 20, 2016.
    Magnesium-Based Energy Storage Systems and Methods Having Improved Electrolytes
    Abstract:Electrolytes for Mg-based energy storage devices can be formed from non-nucleophilic Mg2+ sources to provide outstanding electrochemical performance and improved electrophilic susceptibility compared to electrolytes employing nucleophilic sources. The instant electrolytes are characterized by high oxidation stability (up to 3.4 V vs Mg),improved electrophile compatibility and electrochemical reversibility (up to 100% coulombic efficiency). Synthesis of the Mg2+ electrolytes utilizes inexpensive and safe magnesium dihalides as non-nucleophilic Mg2+ sources in combination with Lewis acids, MRaX3_a (for 3≥a≥1). Furthermore, addition of free-halide-anion donors can improve the coulombic efficiency of Mg electrolytes from nucleophilic or non-nucleophilic Mg2+ sources.
  • U.S. Patent No. 9,444,091, Issued Sep. 13, 2016.
    Apparatuses for making cathodes for high-temperature, rechargeable batteries
    Abstract: The approaches and apparatuses for fabricating cathodes can be adapted to improve control over cathode composition and to better accommodate batteries of any shape and their assembly. For example, a first solid having an alkali metal halide, a second solid having a transition metal, and a third solid having an alkali metal aluminum halide are combined into a mixture. The mixture can be heated in a vacuum to a temperature that is greater than or equal to the melting point of the third solid. When the third solid is substantially molten liquid, the mixture is compressed into a desired cathode shape and then cooled to solidify the mixture in the desired cathode shape.
  • U.S. Patent No. 9,437,880, Issued Sep. 6, 2016.
    Method of manufacturing a fuel cell stack having an electrically conductive interconnect
    Abstract: A method of manufacturing a solid oxide fuel cell stack having an electrically conductive interconnect, including the steps of: (a) providing a first fuel cell and a second fuel cell, (b) providing a substrate having an iron-chromium alloy, (c) depositing a layer of metallic cobalt over a portion of substrate surface, (d) subjecting the layer of metallic cobalt to reducing conditions, (e) then exposing the remaining portion of the layer of metallic cobalt to oxidizing conditions for a predetermined time and temperature, such that the surface portion of the layer of metallic cobalt is oxidized to cobalt oxide, thereby forming the electrically conductive interconnect having a layer of metallic cobalt sandwiched between a surface layer of cobalt oxide and the layer of cobalt-iron-chromium alloy, and (f) sandwiching the substrate between the first and second fuel cells.
  • U.S. Patent No. 9,437,899, Issued Sep. 6, 2016.
    Solid-state rechargeable magnesium battery
    Abstract: Embodiments of a solid-state electrolyte comprising magnesium borohydride, polyethylene oxide, and optionally a Group IIA or transition metal oxide are disclosed. The solid-state electrolyte may be a thin film comprising a dispersion of magnesium borohydride and magnesium oxide nanoparticles in polyethylene oxide. Rechargeable magnesium batteries including the disclosed solid-state electrolyte may have a coulombic efficiency ≧95% and exhibit cycling stability for at least 50 cycles.
  • U.S. Patent No. 9,406,960, Issued Aug. 2, 2016.
    Energy storage systems having an electrode comprising LixSy
    Abstract: Improved lithium-sulfur energy storage systems can utilizes LixSy as a component in an electrode of the system. For example, the energy storage system can include a first electrode current collector, a second electrode current collector, and an ion-permeable separator separating the first and second electrode current collectors. A second electrode is arranged between the second electrode current collector and the separator. A first electrode is arranged between the first electrode current collector and the separator and comprises a first condensed-phase fluid comprising LixSy. The energy storage system can be arranged such that the first electrode functions as a positive or a negative electrode.
  • U.S. Patent No. 9,368,824, Issued Jun. 14, 2016.
    Iron-sulfide redox flow batteries
    Abstract: Iron-sulfide redox flow battery (RFB) systems can be advantageous for energy storage, particularly when the electrolytes have pH values greater than 6. Such systems can exhibit excellent energy conversion efficiency and stability and can utilize low-cost materials that are relatively safer and more environmentally friendly. One example of an iron-sulfide RFB is characterized by a positive electrolyte that comprises Fe(III) and/or Fe(II) in a positive electrolyte supporting solution, a negative electrolyte that comprises S2− and/or S in a negative electrolyte supporting solution, and a membrane, or a separator, that separates the positive electrolyte and electrode from the negative electrolyte and electrode.
  • U.S. Patent No. 9,356,314, Issued May. 31, 2016.
    Metallization pattern on solid electrolyte or porous support of sodium battery process
    Abstract: A new battery configuration and process are detailed. The battery cell includes a solid electrolyte configured with an engineered metallization layer that distributes sodium across the surface of the electrolyte extending the active area of the cathode in contact with the anode during operation. The metallization layer enhances performance, efficiency, and capacity of sodium batteries at intermediate temperatures at or below about 200°C.
  • U.S. Patent No. 9,276,294, Issued Mar. 1, 2016.
    Planar high density sodium battery
    Abstract: A method of making a molten sodium battery is disclosed. A first metallic interconnect frame having a first interconnect vent hole is provided. A second metallic interconnect frame having a second interconnect vent hole is also provided. An electrolyte plate having a cathode vent hole and an anode vent hole is interposed between the metallic interconnect frames. The metallic interconnect frames and the electrolyte plate are sealed thereby forming gaseous communication between an anode chamber through the anode vent hole and gaseous communication between a cathode chamber through the cathode vent hole.
  • U.S. Patent No. 9,252,461, Issued Feb. 2, 2016.
    Hybrid energy storage devices having sodium
    Abstract: Sodium energy storage devices employing aspects of both ZEBRA batteries and traditional Na—S batteries can perform better than either battery alone. The hybrid energy storage devices described herein can include a sodium anode, a molten sodium salt catholyte, and a positive electrode that has active species containing sulfur. Additional active species can include a transition metal source and NaCl. As a product of the energy discharge process, Na2Sx forms in which x is less than three.
  • U.S. Patent No. 9,236,620, Issued Jan. 12, 2016.
    Composite separators and redox flow batteries based on porous separators
    Abstract: Composite separators having a porous structure and including acid-stable, hydrophilic, inorganic particles enmeshed in a substantially fully fluorinated polyolefin matrix can be utilized in a number of applications. The inorganic particles can provide hydrophilic characteristics. The pores of the separator result in good selectivity and electrical conductivity. The fluorinated polymeric backbone can result in high chemical stability. Accordingly, one application of the composite separators is in redox flow batteries as low cost membranes. In such applications, the composite separator can also enable additional property-enhancing features compared to ion-ex-change membranes. For example, simple capacity control can be achieved through hydraulic pressure by balancing the volumes of electrolyte on each side of the separator. While a porous separator can also allow for volume and pressure regulation in RFBs that utilize corrosive and/or oxidizing compounds, the composite separators described herein are preferable for their robustness in the presence of such compounds.

2015

  • U.S. Patent No. 9,214,695, Issued Dec. 15, 2015.
    Hybrid anodes for redox flow batteries
    Abstract: RFBs having solid hybrid electrodes can address at least the problems of active material consumption, electrode passivation, and metal electrode dendrite growth that can be characteristic of traditional batteries, especially those operating at high current densities. The RFBs each have a first half cell containing a first redox couple dissolved in a solution or contained in a suspension. The solution or suspension can flow from a reservoir to the first half cell. A second half cell contains the solid hybrid electrode, which has a first electrode connected to a second electrode, thereby resulting in an equi-potential between the first and second electrodes. The first and second half cells are separated by a separator or membrane.
  • U.S. Patent No. 9,130,218, Issued Sep. 8, 2015.
    Hybrid energy storage systems utilizing redox active organic compounds
    Abstract: Redox flow batteries (RFB) have attracted considerable interestdue to their ability to store large amounts of power and energy. Non-aqueous energy storage systems that utilize at least some aspects of RFB systems are attractive because they can offer an expansion of the operating potential window, which can improve on the system energy and power densities. One example of such systems has a separator separating first and second electrodes. The first electrode includes a first current collector and volume containing a first active material. The second electrode includes a second current collector and volume containing a second active material. During operation, the first source provides a flow of first active material to the first volume. The first active material includes a redox active organic compound dissolved in a non-aqueous, liquid electrolyte and the second active material includes a redox active metal.
  • U.S. Patent No. 9,123,931, Issued Sep. 1, 2015.
    Redox flow batteries based on supporting solutions containing chloride
    Abstract: Redox flow battery systems having a supporting solution that contains C1- ions can exhibit improved performance and characteristics. Furthermore, a supporting solution having mixed SO42- and C1- ions can provide increased energy density and improved stability and solubility of one or more of the ionic species in the catholyte and/or anolyte. According to one example, a vanadium-based redox flow battery system is characterized by an anolyte having V2+ and V3+ in a supporting solution and a catholyte having V4+ and V5+ in a supporting solution. The supporting solution can contain C1- ions or a mixture of SO42- and C-1 ions. *(CIP of US 8,628,880 issued Jan 14, 2014)
  • U.S. Patent No. 9,077,011, Issued Jul. 7, 2015.
    Redox flow batteries based on supporting solutions containing chloride
    Abstract: Redox flow battery systems having a supporting solution that contains C1- ions can exhibit improved performance and characteristics. Furthermore, a supporting solution having mixed SO42- and C1- ions can provide increased energy density and improved stability and solubility of one or more of the ionic species in the catholyte and/or anolyte. According to one example, a vanadium-based redox flow battery system is characterized by an anolyte having V2+ and V3+ in a supporting solution and a catholyte having V4+ and V5+ in a supporting solution. The supporting solution can contain C1- ions or a mixture of SO42- and C-1 ions. *(CIP of US 8,628,880 issued Jan 14, 2014)
  • U.S. Patent No. 9,023,529, Issued May. 5, 2015.
    Nanomaterials for sodium-ion batteries
    Abstract: A crystalline nanowire and method of making a crystalline nanowire are disclosed. The method includes dissolving a first nitrate salt and a second nitrate salt in an acrylic acid aqueous solution. An initiator is added to the solution, which is then heated to form polyacrylatyes. The polyacrylates are dried and calcined. The nanowires show high reversible capacity, enhanced cycleability, and promising rate capability for a battery or capacitor.

2014

  • U.S. Patent No. 8,771,856, Issued Jul. 8, 2014.
    Fe-V redox flow batteries
    Abstract: A redox flow battery having a supporting solution that includes Cl anions is characterized by an anolyte having V2+ and V3+ in the supporting solution, a catholyte having Fe2+ and Fe3+ in the supporting solution, and a membrane separating the anolyte and the catholyte. The anolyte and catholyte can have V cations and Fe cations, respectively, or the anolyte and catholyte can each contain both V and Fe cations in a mixture. Furthermore, the supporting solution can contain a mixture of SO4 2− and Cl ¯ anions.
  • U.S. Patent No. 8,728,174, Issued May. 20, 2014.
    Methods and apparatuses for making cathodes for high-temperature, rechargeable batteries
    Abstract: The approaches for fabricating cathodes can be adapted to improve control over cathode composition and to better accommodate batteries of any shape and their assembly. For example, a first solid having an alkali metal halide, a second solid having a transition metal, and a third solid having an alkali metal aluminum halide are combined into a mixture. The mixture can be heated in a vacuum to a temperature that is greater than or equal to the melting point of the third solid. When the third solid is substantially molten liquid, the mixture is compressed into a desired cathode shape and then cooled to solidify the mixture in the desired cathode shape.
  • U.S. Patent No. 8,628,880, Issued Jan. 14, 2014.
    Redox flow batteries based on supporting solutions containing chloride
    Abstract: Redox flow battery systems having a supporting solution that contains C1- ions can exhibit improved performance and characteristics. Furthermore, a supporting solution having mixed SO42- and C1- ions can provide increased energy density and improved stability and solubility of one or more of the ionic species in the catholyte and/or anolyte. According to one example, a vanadium-based redox flow battery system is characterized by an anolyte having V2+ and V3+ in a supporting solution and a catholyte having V4+ and V5+ in a supporting solution. The supporting solution can contain C1- ions or a mixture of SO42- and C-1 ions.

2013

  • U.S. Patent No. 8,609,270, Issued Dec. 17, 2013.
    Iron-sulfide redox flow batteries
    Abstract: Iron-sulfide redox flow battery (RFB) systems can be advantageous for energy storage, particularly when the electrolytes have pH values greater than 6. Such systems can exhibit excellent energy conversion efficiency and stability and can utilize low-cost materials that are relatively safer and more environmentally friendly. One example of an iron-sulfide RFB is characterized by a positive electrolyte that comprises Fe(III) and/or Fe(II) in a positive electrolyte supporting solution, a negative electrolyte that comprises S2- and/or S in a negative electrolyte supporting solution, and a membrane, or a separator, that separates the positive electrolyte and electrode from the negative electrolyte and electrode.
  • U.S. Patent No. 8,450,014, Issued May. 28, 2013.
    Lithium-ion batteries with titania/graphene anodes
    Abstract: Lithium ion batteries having an anode comprising at least one graphene layer in electrical communication with titania to form a nanocomposite material, a cathode comprising a lithium olivine structure, and an electrolyte. The graphene layer has a carbon to oxygen ratio of between 15 to 1 and 500 to 1 and a surface area of between 400 and 2630 m2/g. The nanocomposite material has a specific capacity at least twice that of a titania material without graphene material at a charge/discharge rate greater than about 10 C. The olivine structure of the cathode of the lithium ion battery of the present invention is LiMPO4 where M is selected from the group consisting of Fe, Mn, Co, Ni and combinations thereof.

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