Abstract: An alkaline cell having an anode comprising zinc, an alkaline electrolyte solution, a separator, and a cathode comprising copper iodate. The cathode preferably also includes a graphitic carbon to improve electrical conductivity. The graphtic carbon can comprise natural or synthetic graphites including expanded graphites and graphitic carbon fibers. Preferably, the graphitic carbon comprises graphitic carbon nanofibers. The carbon nanofibers desirably have a mean average diameter less than 500 nanometers. The cathode can also include sulfur in admixture with the copper iodate to improve cell performance.

Abstract: An alkaline cell having an anode comprising zinc, an alkaline electrolyte solution, a separator, and a cathode comprising copper iodate. The cathode preferably also includes a graphitic carbon to improve electrical conductivity. The graphtic carbon can comprise natural or synthetic graphites including expanded graphites and graphitic carbon fibers. Preferably, the graphitic carbon comprises graphitic carbon nanofibers. The carbon nanofibers desirably have a mean average diameter less than 500 nanometers. The cathode can also include sulfur in admixture with the copper iodate to improve cell performance.

Abstract: A process is described whereby commercial manganese dioxide, for example, electrolytic manganese dioxide (EMD), is treated with ozone before it is utilized as cathode active material in an alkaline cell. The pretreatment of the manganese dioxide is accomplished by contacting manganese dioxide with ozone gas. Alternatively, the manganese dioxide may be treated with ozone while the cathode comprising said manganese dioxide is already in the cell casing. The treatment of the manganese dioxide improves the cell's open circuit voltage (OCV) and results in an increase in service life of the cell, particularly under high power application.

Abstract: A method of making lithium manganese oxide of spinel structure is disclosed. The method involves the step of prelithiating a manganese oxide by reacting it with lithium hydroxide or lithium salt and then reacting the prelithiated manganese oxide in a second step at elevated temperature, for example, with lithium carbonate to form a lithium manganese oxide spinel. The spinel product may be used advantageously in secondary (rechargeable) batteries. The spinel product may be admixed with a partially substituted nickelite, preferably, LiNi.sub.x Co.sub.1-x O.sub.2 (0.1<x<0.9) or LiNi.sub.x Mg.sub.1-x O.sub.2 (0.85<x<0.97) and mixtures thereof to form the active material for the positive electrode of a rechargeable lithium ion cell. A preferred mixture for the positive electrode of lithium ion cells comprises lithium manganese oxide spinel and LiNi.sub.x Co.sub.1-x O.sub.2 (0.1<x<0.9).

Abstract: A method of treating lithium manganese oxide of spinel structure is disclosed. The method involves heating the lithium manganese oxide spinel in an atmosphere of an inert gas, e.g, argon, helium, nitrogen or carbon dioxide, which does not react with the spinel. Alternatively, the spinel may be first coated with an alkali metal hydroxide, preferably lithium, sodium or potassium hydroxide and then heated in an atmosphere preferably containing carbon dioxide. Such treatment of lithium manganese oxide spinel improves the performance of the spinel when employed as an electrode in rechargeable cells such as lithium-ion cells. Alternatively, the spinel may be first treated in an aqueous solution of a soluble metal salt of a carboxylic acid prior to treatment with heated carbon dioxide or inert gas. In such latter case the spinel may optionally also be treated with an alkali metal hydroxide prior to treatment with carbon dioxide or inert gas.

Abstract: A method of making lithium manganese oxide of spinel structure is disclosed. The method involves the step of prelithiating a manganese oxide by reacting it with lithium hydroxide or lithium salt and then reacting the prelithiated manganese oxide in a second step at elevated temperature to form a lithium manganese oxide spinel. In a specific embodiment manganese dioxide powder is reacted with lithium hydroxide to prelithiate the manganese dioxide and the prelithiated manganese dioxide is separated from the reaction mixture and heated and reacted with lithium carbonate at elevated temperature to convert it to lithium manganese oxide spinel. The spinel product may be used advantageously in secondary (rechargeable) batteries.

Abstract: A method of treating lithium manganese oxide of spinel structure is disclosed. The method involves heating the lithium manganese oxide spinel in an atmosphere of an inert gas which does not react with the spinel. Such gases may be selected advantageously from argon, helium, nitrogen, and carbon dioxide. Preferred nonreacting gases which may be employed for spinel treatment are nitrogen or carbon dioxide. The spinel is advantageously treated with such gases at elevated temperatures. Alternatively, the spinel may be first coated with a hydroxide, preferably lithium, sodium or potassium hydroxide and then heated in an atmosphere of carbon dioxide gas at elevated temperatures. Such treatment of lithium manganese oxide spinel has been determined to improve the performance of the spinel when employed as an electrode in rechargeable cells such as lithium-ion cells.

Abstract: The invention relates to the manufacture of manganese dioxide by a chemical process. The resulting product takes the form of gamma manganese dioxide particles characterized by filament-like protrusions of ramsdellite manganese dioxide jutting out from the surface of the particles. The manganese dioxide particles having such features can be manufactured by reacting manganese sulfate with sodium peroxodisulfate in an aqueous solution. The process can be controlled to yield high density manganese dioxide. The manganese dioxide formed in the process can be deposited directly onto the surface of electrolytic manganese dioxide (EMD). The manganese dioxide product is particularly suitable for use as a cathode active material in electrochemical cells.

Abstract: The invention relates to the manufacture of manganese dioxide by a chemical process. The resulting manganese dioxide product takes the form of particles characterized by filament-like protrusions jutting out from its surface. The manganese dioxide particles having such surface features can be manufactured by reacting manganese sulfate with sodium peroxodisulfate in an aqueous solution. The process can be controlled to yield high density manganese dioxide. The manganese dioxide formed in the process can be deposited directly onto the surface of electrolytic manganese dioxide (EMD). The manganese dioxide product is particularly suitable for use as a cathode active material in electrochemical cells.

Abstract: The invention relates to the manufacture of manganese dioxide by a chemical process. The resulting manganese dioxide product takes the form of particles characterized by filament-like protrusions jutting out from its surface. The manganese dioxide particles having such surface features can be manufactured by reacting manganese sulfate with sodium peroxodisulfate in an aqueous solution. The process can be controlled to yield manganese dioxide of varying density and surface area. The manganese dioxide formed in the process can be deposited directly onto the surface of electrolytic manganese dioxide (EMD) or onto the surface of other particles. The manganese dioxide product is particularly suitable for use as a cathode active material in electrochemical cells.

Abstract: The invention relates to the manufacture of manganese dioxide by a chemical process. The resulting manganese dioxide product takes the form of particles characterized by filament-like protrusions jutting out from its surface. The manganese dioxide particles having such surface features can be manufactured by reacting manganese sulfate with sodium peroxodisulfate in an aqueous solution. The process can be controlled to yield high density manganese dioxide. The manganese dioxide formed in the process can be deposited directly onto the surface of electrolytic manganese dioxide (EMD). The manganese dioxide product the is particularly suitable for use as a cathode active material in electrochemical cells.

Abstract: The invention relates to the manufacture of manganese dioxide by a chemical process. The resulting manganese dioxide product takes the form of particles characterized by filament-like protrusions jutting out from its surface. The manganese dioxide particles having such surface features can be manufactured by reacting manganese sulfate with sodium peroxodisulfate in an aqueous solution. The process can be controlled to yield high density manganese dioxide. The manganese dioxide formed in the process can be deposited directly onto the surface of electrolytic manganese dioxide (EMD). The manganese dioxide product the is particularly suitable for use as a cathode active material in electrochemical cells.