Abstract: Disclosed herein is a method of processing carbonaceous material that includes combining a first stream of a first carbonaceous material and a second stream of a second carbonaceous material into a combined stream of carbonaceous material. A parameter of the first carbonaceous material has a first value and the parameter of the second carbonaceous material has a second value that is different than the first value. The method also includes removing only a portion of an impurity, a contaminant, or a combination of the impurity and the contaminant from the combined stream of carbonaceous material. The method further includes carbonizing the combined stream of carbonaceous material by exposing the combined stream of carbonaceous material to energy in the form at least one of: heat, electricity, microwave radiation, or light. The method additionally includes converting the combined stream of carbonaceous material into activated carbon.

Abstract: A method of managing energy for a supercapacitor includes charging a plurality of cells of an energy storage module of a supercapacitor during a charge cycle. The energy storage module includes a plurality of strings connected to each other in a parallel configuration. Each string of the plurality of strings includes a plurality of stacks connected to each other in a series configuration. Each stack of the plurality of stacks includes a quantity of cells of the plurality of cells. The method includes, during the charge cycle, measuring a voltage of a cell of the plurality of cells. The method includes, during the charge cycle, and based at least in part on the measured voltage, increasing a quantity of the plurality of strings by decreasing a quantity of the stacks of at least one string of the plurality of strings.

Abstract: The present disclosure provides methods and devices for preparing electrolyte solutions containing unwanted impurities at the ?g/L levels. The methods generally comprise electrochemically reducing the impurity to a precipitated, plated, or volatilized form, and removing that reduced form from electrolyte solution. This disclosure describes the methods and devices for effecting such methods, and the electrochemical solutions derived or derivable from such methods.

Abstract: The present disclosure provides methods and devices for preparing electrolyte solutions containing unwanted impurities at the pg/L levels. The methods generally comprise electrochemically reducing the impurity to a precipitated, plated, or volatilized form, and removing that reduced form from electrolyte solution. This disclosure describes the methods and devices for effecting such methods, and the electrochemical solutions derived or derivable from such methods.

Abstract: Electrolyte solutions for flow batteries and other electrochemical systems can contain an active material that is capable of transferring one or more electrons per molecule during an oxidation-reduction cycle. Doubly bridged aromatic groups or their coordination compounds can be particularly suitable active materials. Flow batteries can include a first half-cell containing a first electrolyte solution, and a second half-cell containing a second electrolyte solution, in which at least one of the first electrolyte solution and the second electrolyte solution contains an active material having at least two aromatic groups doubly bridged by a carbonyl moiety and a bridging moiety containing a bridging atom selected from carbon, nitrogen, oxygen, sulfur, selenium and tellurium. Such bridged compounds can directly function as the active material, or coordination compounds containing the bridged compounds as at least one ligand can serve as the active material.

Abstract: Flow batteries can include a first half-cell containing a first aqueous electrolyte solution. a second half-cell containing a second aqueous electrolyte solution, and a separator disposed between the first half-cell and the second half-cell, The first aqueous electrolyte solution contains a first redox-active material, and the second aqueous electrolyte solution contains a second redox-active material. At least one of the first redox-active material and the second redox-active material is a nitroxide compound or a salt thereof. Particular nitroxide compounds can include a doubly bonded oxygen contained in a ring bearing the nitroxide group, a doubly bonded oxygen appended to a ring bearing the nitroxide group, sulfate or phosphate groups appended to a ring bearing the nitroxide group, various heterocyclic rings bearing the nitroxide group, or acyclic nitroxide compounds.

Abstract: Flow batteries can include a first half-cell containing a first aqueous electrolyte solution. a second half-cell containing a second aqueous electrolyte solution, and a separator disposed between the first half-cell and the second half-cell. The first aqueous electrolyte solution contains a first redox-active material, and the second aqueous electrolyte solution contains a second redox-active material. At least one of the first redox-active material and the second redox-active material is a nitroxide compound or a salt thereof. Particular nitroxide compounds can include a doubly bonded oxygen contained in a ring bearing the nitroxide group, a doubly bonded oxygen appended to a ring bearing the nitroxide group, sulfate or phosphate groups appended to a ring bearing the nitroxide group, various heterocyclic rings bearing the nitroxide group, or acyclic nitroxide compounds.

Abstract: The present disclosure provides methods and devices for preparing electrolyte solutions containing unwanted impurities at the pg/L levels. The methods generally comprise electrochemically reducing the impurity to a precipitated, plated, or volatilized form, and removing that reduced form from electrolyte solution. This disclosure describes the methods and devices for effecting such methods, and the electrochemical solutions derived or derivable from such methods.

Abstract: Flow batteries can include a first half-cell containing a first aqueous electrolyte solution, a second half-cell containing a second aqueous electrolyte solution, and a separator disposed between the first half-cell and the second half-cell, The first aqueous electrolyte solution contains a first redox-active material, and the second aqueous electrolyte solution contains a second redox-active material. At least one of the first redox-active material and the second redox-active material is a nitroxide compound or a salt thereof. Particular nitroxide compounds can include a doubly bonded oxygen contained in a ring bearing the nitroxide group, a doubly bonded oxygen appended to a ring bearing the nitroxide group, sulfate or phosphate groups appended to a ring bearing the nitroxide group, various heterocyclic rings bearing the nitroxide group, or acyclic nitroxide compounds.

Abstract: Electrolyte solutions for flow batteries and other electrochemical systems can contain an active material that is capable of transferring one or more electrons per molecule during an oxidation-reduction cycle. Doubly bridged aromatic groups or their coordination compounds can be particularly suitable active materials. Flow batteries can include a first half-cell containing a first electrolyte solution, and a second half-cell containing a second electrolyte solution, in which at least one of the first electrolyte solution and the second electrolyte solution contains an active material having at least two aromatic groups doubly bridged by a carbonyl moiety and a bridging moiety containing a bridging atom selected from carbon, nitrogen, oxygen, sulfur, selenium and tellurium. Such bridged compounds can directly function as the active material, or coordination compounds containing the bridged compounds as at least one ligand can serve as the active material.

Abstract: Flow batteries can include a first half-cell containing a first aqueous electrolyte solution, a second half-cell containing a second aqueous electrolyte solution, and a separator disposed between the first half-cell and the second half-cell. The first aqueous electrolyte solution contains a first redox-active material, and the second aqueous electrolyte solution contains a second redox-active material. At least one of the first redox-active material and the second redox-active material is a nitroxide compound or a salt thereof. Particular nitroxide compounds can include a doubly bonded oxygen contained in a ring bearing the nitroxide group, a doubly bonded oxygen appended to a ring bearing the nitroxide group, sulfate or phosphate groups appended to a ring bearing the nitroxide group, various heterocyclic rings bearing the nitroxide group, or acyclic nitroxide compounds.

Abstract: Electrolyte solutions for flow batteries and other electrochemical systems can contain an active material that is capable of transferring one or more electrons per molecule during an oxidation-reduction cycle. Doubly bridged aromatic groups or their coordination compounds can be particularly suitable active materials. Flow batteries can include a first half-cell containing a first electrolyte solution, and a second half-cell containing a second electrolyte solution, in which at least one of the first electrolyte solution and the second electrolyte solution contains an active material having at least two aromatic groups doubly bridged by a carbonyl moiety and a bridging moiety containing a bridging atom selected from carbon, nitrogen, oxygen, sulfur, selenium and tellurium. Such bridged compounds can directly function as the active material, or coordination compounds containing the bridged compounds as at least one ligand can serve as the active material.

Abstract: Titanium catecholate complexes can be desirable active materials for flow batteries and other electrochemical energy storage systems, particularly when incorporated in aqueous electrolyte solutions. It can be desirable to avoid introducing certain organic solvents and/or extraneous salts into aqueous electrolyte solutions. Methods for synthesizing titanium catecholate complexes that can help avoid the unwanted introduction of organic solvents and/or extraneous salts into aqueous electrolyte solutions can include: providing an aqueous solution containing a catechol compound, reacting a titanium reagent with the catechol compound in the aqueous solution to form an intermediate titanium catecholate complex, isolating the intermediate titanium catecholate complex as a solid or slurry, and reacting a ligatable compound with the intermediate titanium catecholate complex in the presence of a base to produce a salt form titanium catecholate complex containing at least one additional ligand.

Abstract: Flow batteries and other electrochemical systems can contain an active material that is a coordination complex having at least one monosulfonated catecholate ligand or a salt thereof bound to a metal center. The monosulfonated catecholate ligand has a structure of More particularly, the coordination complex can be a titanium coordination complex with a formula of DgTi(L1)(L2)(L3), in which D is a counterion selected from H, NH4+, Li+, Na+, K+, or any combination thereof; g ranges between 3 and 6; and L1, L2 and L3 are ligands, where at least one of L1, L2 and L3 is a monosulfonated catecholate ligand. Methods for synthesizing such monosulfonated catecholate ligands can include providing a neat mixture of catechol and up to about 1.3 stoichiometric equivalents of sulfuric acid, and heating the neat mixture at a temperature of about 80° C. or above to form 3,4-dihydroxybenzenesulfonic acid or a salt thereof.

Abstract: Flow batteries and other electrochemical systems can contain an active material that is a coordination complex having at least one monosulfonated catecholate ligand or a salt thereof bound to a metal center. The monosulfonated catecholate ligand has a structure of More particularly, the coordination complex can be a titanium coordination complex with a formula of DgTi(L1)(L2)(L3), in which D is a counterion selected from H, NH4+, Li+, Na+, K+, or any combination thereof g ranges between 3 and 6; and L1, L2 and L3 are ligands, where at least one of L1, L2 and L3 is a monosulfonated catecholate ligand. Methods for synthesizing such monosulfonated catecholate ligands can include providing a neat mixture of catechol and up to about 1.3 stoichiometric equivalents of sulfuric acid, and heating the neat mixture at a temperature of about 80° C. or above to form 3,4-dihydroxybenzenesulfonic acid or a salt thereof.

Abstract: Flow batteries can include a first half-cell containing a first aqueous electrolyte solution, a second half-cell containing a second aqueous electrolyte solution, and a separator disposed between the first half-cell and the second half-cell. The first aqueous electrolyte solution contains a first redox-active material, and the second aqueous electrolyte solution contains a second redox-active material. At least one of the first redox-active material and the second redox-active material is a nitroxide compound or a salt thereof. Particular nitroxide compounds can include a doubly bonded oxygen contained in a ring bearing the nitroxide group, a doubly bonded oxygen appended to a ring bearing the nitroxide group, sulfate or phosphate groups appended to a ring bearing the nitroxide group, various heterocyclic rings bearing the nitroxide group, or acyclic nitroxide compounds.

Abstract: Coordinatively saturated titanium (IV) coordination compounds containing catecholate ligands can be desirable active materials for flow batteries and other electrochemical energy storage systems. Such coordination compounds can be formed advantageously via an intermediate composition containing a coordinatively unsaturated titanium (IV) coordination compound. More specifically, such compositions can include a coordinatively unsaturated titanium (IV) coordination compound having a coordination number of 5 or less and containing two catecholate ligands, wherein the composition is substantially free of non-ligated catechol compound.

Abstract: Titanium complexes containing at least one catecholate ligand can be desirable active materials for flow batteries and other electrochemical energy storage systems. Such complexes can be formed through reacting a catechol compound with a titanium reagent in an organic solvent, removing a byproduct species, and then obtaining an aqueous phase containing a salt form of the titanium catechol complex, particularly an alkali metal salt form.

Abstract: Titanium complexes containing catecholate ligands can be desirable active materials for flow batteries and other electrochemical energy storage systems. Such complexes can be formed, potentially on very large scales, through reacting a catechol compound in an organic solvent with titanium tetrachloride, and then obtaining an aqueous phase containing an alkali metal salt form of the titanium catechol complex. More specifically, the methods can include: forming a catechol solution and heating, adding titanium tetrachloride to the catechol solution, reacting the titanium tetrachloride with a catechol compound to evolve HCl gas and to form an intermediate titanium catechol complex, and adding an alkaline aqueous solution to the intermediate titanium catechol complex to form an alkali metal salt form titanium catechol complex that is at least partially dissolved in an aqueous phase. The aqueous phase can be separated from an organic phase.

Abstract: Coordination complexes can have a metal center with at least one unsubstituted catecholate ligand and at least one monosulfonated catecholate ligand or a salt thereof bound thereto. Some coordination complexes can have a formula of DgTi(L1)x(L2)y, in which D is a counterion selected from NH4+, Li+, Na+, K+, or any combination thereof; g ranges between 2 and 6; L1 is an unsubstituted catecholate ligand; L2 is a monosulfonated catecholate ligand; and x and y are non-zero numbers such that x+y=3. Methods for synthesizing such coordination complexes can include providing a neat mixture of catechol and a sub-stoichiometric amount of sulfuric acid, heating the neat mixture to form a reaction product containing catechol and a monosulfonated catechol or a salt thereof, and forming a coordination complex from the reaction product without separating the catechol and the monosulfonated catechol or the salt thereof from one another.