Methods and systems for the controlled production of aqueous halogen solutions with varying compositions are disclosed. According to an embodiment, aqueous solutions of hypochlorite ions are modified through the sequential addition of pH adjusting chemicals, non-chloride halide ions, and halogen stabilizing compounds. Sensors, for measuring physical and chemical properties of the solutions as they change due to the impact of the various chemical reactions, are linked to a control system which, in turn, can control the input of one or more chemicals. The control system facilitates the production of a solution with desired characteristics in terms of pH, specific halogen composition, degree of halogen stabilization, and limiting the production of undesired by products such as bromate ions.

Methods and systems for the controlled production of aqueous halogen solutions with varying compositions are disclosed. According to an embodiment, aqueous solutions of hypochlorite ions are modified through the sequential addition of pH adjusting chemicals, non-chloride halide ions, and halogen stabilizing compounds. Sensors, for measuring physical and chemical properties of the solutions as they change due to the impact of the various chemical reactions, are linked to a control system which, in turn, can control the input of one or more chemicals. The control system facilitates the production of a solution with desired characteristics in terms of pH, specific halogen composition, degree of halogen stabilization, and limiting the production of undesired by products such as bromate ions.

The reaction of sodium hypochlorite with sodium bromide is slow, and commonly only part of the bromide is converted to hypobromite. Methods to accelerate the reaction by adding a regulated amount of acid to a solution comprising bleach and bromide are provided, whereby the yield of hypobromite can be increased. The amount of acid added can be predetermined based on the content of a base in the bleach, and acid can be added to neutralize the base. The amount of acid added can be based on a measured parameter of the reaction that is indicative of reaction kinetics. For example, the amount of acid can be actively controlled by measuring pH, absorbance of visible or near Ultraviolet light, or temperature of the reacting solution and adjusting acid.

The reaction of sodium hypochlorite with sodium bromide is slow, and commonly only part of the bromide is converted to hypobromite. Methods to accelerate the reaction by adding a regulated amount of acid to a solution comprising bleach and bromide are provided, whereby the yield of hypobromite can be increased. The amount of acid added can be predetermined based on the content of a base in the bleach, and acid can be added to neutralize the base. The amount of acid added can be based on a measured parameter of the reaction that is indicative of reaction kinetics. For example, the amount of acid can be actively controlled by measuring pH, absorbance of visible or near Ultraviolet light, or temperature of the reacting solution and adjusting acid.

A positive-electrode active material for a non-aqueous electrolyte secondary battery according to the present disclosure contains a layered lithium (Li)-containing transition metal composite oxide that contains Li in the transition metal layer and more than 0.4 μmol/g and less than 25 μmol/g of iodine (I) or bromine (Br).

A positive-electrode active material for a non-aqueous electrolyte secondary battery according to the present disclosure contains a layered lithium (Li)-containing transition metal composite oxide that contains Li in the transition metal layer and more than 0.4 μmol/g and less than 25 μmol/g of iodine (I) or bromine (Br).

Provided is a method for producing a one-liquid stabilized hypobromous acid composition which contains substantially no bromate ions, has excellent sterilization performance, exhibits almost no corrosiveness relative to metals, and displays excellent storage stability. This method for producing the stabilized hypobromous acid composition includes a step in which a reaction is induced by adding, under an inert gas atmosphere, bromine to a mixed solution including water, an alkali hydroxide, and sulfamic acid, wherein the proportion of bromine added is not more than 25 wt % relative to the total weight of the composition.

Provided is a method for producing a one-liquid stabilized hypobromous acid composition which contains substantially no bromate ions, has excellent sterilization performance, exhibits almost no corrosiveness relative to metals, and displays excellent storage stability. This method for producing the stabilized hypobromous acid composition includes a step in which a reaction is induced by adding, under an inert gas atmosphere, bromine to a mixed solution including water, an alkali hydroxide, and sulfamic acid, wherein the proportion of bromine added is not more than 25 wt % relative to the total weight of the composition.

Na-rich electrolyte compositions provided herein can be used in a variety of devices, such as sodium ionic batteries, capacitors and other electrochemical devices. Na-rich electrolyte compositions provided herein can have a chemical formula of Na.sub.3OX, Na.sub.3SX, Na .sub.(3-δ) M.sub.δ/2OX and Na .sub.(3-δ) M.sub.δ/2SX wherein 0<δ<0.8, wherein X is a monovalent anion selected from fluoride, chloride, bromide, iodide, H.sup.−, CN.sup.−, BF.sub.4.sup.−, BH.sub.4.sup.−, ClO.sub.4.sup.−, CH.sub.3.sup.−, NO.sub.2.sup.−, NH.sub.2.sup.− and mixtures thereof, and wherein M is a divalent metal selected from the group consisting of magnesium, calcium, barium, strontium and mixtures thereof. Na-rich electrolyte compositions provided herein can have a chemical formula of Na .sub.(3-δ) M.sub.δ/3OX and/or Na .sub.(3-δ) M.sub.δ/3SX; wherein 0<δ<0.5, wherein M is a trivalent cation M.sup.3, and wherein X is selected from fluoride, chloride, bromide, iodide, H.sup.−, CN.sup.−, BF.sub.4.sup.−, BH.sub.4.sup.−, ClO.sub.4.sup.−, CH.sub.3.sup.−, NO.sub.2.sup.−, NH.sup.2− and mixtures thereof. Synthesis and processing methods of NaRAP compositions for battery, capacitor, and other electrochemical applications are also provided.

Na-rich electrolyte compositions provided herein can be used in a variety of devices, such as sodium ionic batteries, capacitors and other electrochemical devices. Na-rich electrolyte compositions provided herein can have a chemical formula of Na.sub.3OX, Na.sub.3SX, Na .sub.(3-δ) M.sub.δ/2OX and Na .sub.(3-δ) M.sub.δ/2SX wherein 0<δ<0.8, wherein X is a monovalent anion selected from fluoride, chloride, bromide, iodide, H.sup.−, CN.sup.−, BF.sub.4.sup.−, BH.sub.4.sup.−, ClO.sub.4.sup.−, CH.sub.3.sup.−, NO.sub.2.sup.−, NH.sub.2.sup.− and mixtures thereof, and wherein M is a divalent metal selected from the group consisting of magnesium, calcium, barium, strontium and mixtures thereof. Na-rich electrolyte compositions provided herein can have a chemical formula of Na .sub.(3-δ) M.sub.δ/3OX and/or Na .sub.(3-δ) M.sub.δ/3SX; wherein 0<δ<0.5, wherein M is a trivalent cation M.sup.3, and wherein X is selected from fluoride, chloride, bromide, iodide, H.sup.−, CN.sup.−, BF.sub.4.sup.−, BH.sub.4.sup.−, ClO.sub.4.sup.−, CH.sub.3.sup.−, NO.sub.2.sup.−, NH.sup.2− and mixtures thereof. Synthesis and processing methods of NaRAP compositions for battery, capacitor, and other electrochemical applications are also provided.