Inco Limited

The International Nickel Company, Inc.

Norvik Technologies Inc.

Other

The United States of America As Represented by the Secretary of

Victor A Ettel

Juraj Babjak

Eric A Devuyst

John Ambrose

Stephen Joseph Baksa

Charles E O'Neill

Aubrey Stewart Gendron

James A Bell

Jiri K Nor

Josef V Soltys

Vladimir Paserin

Shinichiro Abe

Marcel Alin Mosoiu

Peter Joseph Kalal

Ramamritham Sridhar

Lloyd Matt Timberg

Gerald Vernon Glaum

Kirt Kenneth Cushnie

Alexander Illis

John A Thomas

Feng Zou

Raymond Augustus Bradford

Gyula John Borbely

Kenneth R Dymock

Richard S Adams

Douglas K Charles

Paul A Hynek

David L Jones

David K Vallbacka

Konstantin J Schitka

Vladimiri Paserin

Robert William Elliott

Jan Hohercak

Alfredo Villazor

Peter G Garritsen

An improved apparatus and method of producing metal foam is provided which involves optimizing the natural convection of electrolyte through a foam being electroplated by inclining the foam during plating. A diagonal flow of electrolyte though the foam enhances electrolyte turnover within the foam while increasing electroplating efficiency. Further increases in plating efficiency are provided by shifting current density from higher plating zones to lower plating zones.

Apparatus and foam electroplating process

A process for decreasing the crystallinity of nickel hydroxide by generating and supplying large numbers of heteronuclei into the nickel hydroxide producing reaction system. Nickel sulfate and sodium hydroxide are initially forcefully and intimately combined to form a supersaturated solution of heteronuclei. These heteronuclei are introduced into a nickel powder containing slurry wherein nickel hydroxide having a crystallinity FWHM value of greater than about 0.5&deg; is generated.

Method for reducing the crystallinity of nickel hydroxide powders

The process precipitates additives onto nickel hydroxide seeds in an ammonia solution. Then introducing at least one metallic additive into the aqueous solution creates a slurry having a reducing potential. The additive is selected from the group consisting of aluminum, cadmium, cobalt, indium, iron, manganese and zinc. Introducing oxygen into the additive-containing slurry at a controlled rate maintains the reducing potential of the solution. At least one of the additives dissolves into the aqueous solution in excess of the slurry's solution solubility to precipitate the additive in the form of a hydroxide on the nickel hydroxide seeds.

Methods for doping and coating nickel hydroxide

A process for varying the density of porous plated metal foams. Especially useful for battery plate applications, a plated foam is coated with a slurry of predetermined size metal power, particularly nickel, and then sintered. The resultant density of the metal foam may be adjusted as needed.

Method for varying the density of plated foam

This process produces nickel hydroxide from elemental nickel. Introducing elemental nickel into at least a 4N aqueous ammonia solution forms a mixture. Activating the nickel powder of this mixture allows the nickel to react with oxygen in the solution. This results in the dissolving of the nickel, producing a loaded solution containing nickel and hydroxyl ions. The redox potential of the solution remains negative during the dissolution of nickel. Distilling the loaded solution to vaporize the aqueous ammonia solution results in the precipitating of nickel hydroxide.

Process for producing nickel hydroxide from elemental nickel

A porous nickel electrode substrate having a central high conductivity core sandwiched between two layers of porous conductive material such as nickel foam or nickel felt. The porous conductive material is plated with nickel and then sintered. By selectively controlling the plating of nickel on the porous material, variable conductivities may be designed into the substrate.

Porous nickel electrode substrate

The invention provides a method of producing nickel hydroxide from elemental metal. Elemental nickel is first introduced into an aqueous ammonia or ammonia/ammonium salt solution capable of dissolving nickel. The potential, as measured by a standard calomel electrode, is allowed to reach a negative or reducing level. Oxygen is added to the aqueous solution at a rate that maintains the negative potential to facilitate the conversion of elemental nickel to nickel hydroxide. Nickel hydroxide may be readily precipitated from the aqueous solution.

A battery charge is provided which automatically controls the charging process independent of individual battery construction or temperature. Control of the charging process is achieved by periodically interrupting the charging current, determining resistance-free voltage of the battery in fixed intervals after interruptions of current, and comparing the resistance-free voltage with a reference voltage. Reference voltage is automatically determined for each recharging subject by analyzing the change in resistance-free voltage with respect to time during an initial, constant current period to locate certain characteristic points indicative of the onset of overcharge. The charging current is reduced as necessary, so that the resistance-free voltage does not exceed the reference voltage and significant overcharge is avoided.

Battery charger

A process for producing nickel hydroxide from nickel powders, in which the feed nickel powder is directly converted in an aqueous solution containing nitrate and particulate nickel at least at room temperature and a pH in excess of about 6 into nickel hydroxide of a high density. Nickel powders of high surface area, e.g. 0.4 m.sup.2 /g or higher, typically produced by the thermal decomposition of nickel carbonyl, are particularly suitable as feed materials for this process.

Process for producing nickel hydroxide

A charger for rechargeable cells or batteries utilizes a mechanism whereby resistance-free voltage is continually monitored during periodic current-off intervals in the charging process and compared to an independent reference voltage to prevent overcharge. After a certain degree of charge has been obtained, the current is gradually reduced to a finishing charge. Several means are provided for terminating the finishing charge while avoiding overcharge. Another embodiment of a charger provides for measurement of the resistance-free voltage during the current-off period after sufficient time is allowed for the recombination of any oxygen which may have been produced during charging, thus taking into account inherent variations in cells of the same type.

A novel process for the production of nickel hydroxide wherein particulate nickel is reacted with oxygen in the presence of liquid water at a temperature of at least 180.degree. C. The invention also includes the nickel hydroxide product so produced.

Nickel hydroxide

The invention provides an apparatus for metal plating a substrate. The apparatus includes a chamber adapted to receive metal carbonyl gas. The chamber includes an infrared transparent window. The infrared transparent window has a cooling passage filled with liquid coolant. The liquid coolant has a temperature below which decomposition of the metal carbonyl gas occurs. The liquid coolant prevents decomposition of the metal carbonyl gas on the infrared transparent window. The liquid coolant also is substantially infrared transparent for allowing infrared radiation through the infrared transparent window and cooling passage into the chamber. An infrared radiation source sends infrared radiation into the chamber through the infrared transparent window and cooling passage to heat the substrate to a temperature at which decomposition of the metal carbonyl gas occurs.

Infrared window

The invention provides a nickel foam and a method of forming a nickel foam for a nickel containing battery. An open-cell foam structure is placed in a nickel carbonyl gas containing structure. The foam structure is heated to a temperature at which nickel carbonyl decomposes. Nickel from the nickel carbonyl gas decomposes on the foam structure to form a nickel plated foam structure. The nickel plated foam structure is then sintered leaving an open-cell nickel network to form the nickel foam. The open-cells of the nickel foam comprise substantially hollow wires having a substantially uniform transverse cross-section. The nickel foam is further characterized by the conductivity through the nickel foam multiplied by a factor of 3.4 being equal to or greater than the theoretical conductivity of nickel.

Method of forming nickel foam

The cyanide content of waste waters containing the same is removed by treatment with sulfur dioxide or an alkali or alkaline earth metal sulfite or bisulfite in the presence of excess oxygen and a metal catalyst which is perferably copper.

Cyanide removal from aqueous streams

Cobalt salts are produced by dissolving cobalt metal in hydrochloric acid containing a small amount of thiosulfate ions.

Growing community of inventors

Mississauga, Canada

Victor A Ettel