Gm Global Technolgoy Operations, Inc.

Romeo R Witherspoon

Stuart G Meibuhr

Gregory Charles Garabedian

Richard Leighton Adams

Edward Marion Domanski

Armand R Poirier

James Alvin Davis

In a preferred method, electrodes are formed with a catalyzed carbon substrate for use in an electrochemical cell. The catalyzed carbon substrate basically comprises carbon particles having internal and external surfaces defining a plethora of pores; and a pyrolyzed metal-doped copolymer material supported on the internal and external surfaces of the carbon particles. The pyrolyzed metal-doped material is a metal/nitrogen-carbon complex where the metal is complexed with the heterocarbon/nitrogen. Substrates of catalyzed carbon particles are prepared by first reacting an amine compound with formaldehyde and/or polymerized formaldehyde in solution, in the presence of a catalyst, carbon particles and a metal salt, at a temperature and at a rate of stirring sufficient to provide a polymerized product in the form of a gel. Then the gel is heated (pyrolyzed) in an inert atmosphere for a time sufficient to provide the catalytic carbon particles in the form of a powder. The powder is then mixed with a binder, and electrodes are pressed and formed into a suitably shaped substrate of catalytic carbon.

Method of preparing metal-heterocarbon-nitrogen catalyst for

Positive plates are prepared by forming partially oxidized tetrabasic lead sulfate (4 PbO.sub.n . PbSO.sub.4) having at least a part of the oxide (PbO.sub.n) portion in the form of alpha lead dioxide (.varies. - PbO.sub.n), and forming beta lead dioxide (B-PbO.sub.2). Next the oxidized tetrabasic lead sulfate (OXYTTB) and the beta lead dioxide are intermingled in a wet mixture. The wet mixture is applied to the oxidized surface of a lead support substrate. Then, it is heated and pressed for a time and at a temperature and compressive load sufficient to form an adhered or retained coating of active material on the substrate. The OXYTTB is formed by reaction of tetrabasic lead sulfate with magnesium hydroxide and sodium persulfate. Preferably, beta lead dioxide is formed by reacting red lead oxide (Pb.sub.3 O.sub.4) with nitric acid to provide an oxidation product, at least a major portion of which is beta PbO.sub.2, and which has a surface area of at least 10 m.sup.2 /gram.

Lead-acid battery electrode and method of manufacture

In a preferred method, an electrode for a lead-acid battery is prepared in a new continuous process without the conventional curing step. The general procedure for preparing electrodes includes preparing a mixture (paste) comprising an active material precursor and an inhibitor. The active material precursor includes lead oxides having at least 10% by weight lead oxide in the form of Pb.sub.3 O.sub.4 (red lead), and a BET surface area of at least about 0.8 m.sup.2 /gram; desirably about 1.00 to 1.50 m.sup.2 /gram and preferably about 1.0 to 1.25 m.sup.2 /gram. The inhibitor prevents formation of tribasic lead sulfate and tetrabasic lead sulfate from the precursor material, except at elevated temperature. The paste is applied to electrode grids and reacted at elevated temperatures for between about 5 and about 30 minutes, to form the active material of the electrode for both positive and negative electrodes. Plates are then assembled into batteries and charged. Negative electrodes differ from the positive, mainly in the additives used.

Method of forming lead-acid battery electrode

In a preferred embodiment is disclosed a zinc electrode for an alkaline zinc-nickel hydroxide cell wherein zinc-rich active electrode material is bonded to a conductive grid with hydrophilic polyethylene fibers.

Battery having electrode with hydrophilic polymer binder

An improved shape-stable zinc electrode is described for use in a zinc/nickel oxide cell and comprises a diatomaceous calcium silicate material to retain zincate ions in the area that they form for subsequent recovery there of the zinc.

Zinc electrode containing porous calcium silicate

An interelectrode separator for a secondary zinc alkaline battery comprising talc platelets in a fibrillated polytetrafluoroethylene binder with or without calcium acetate, calcium formate or zirconyl acetate and a method of making same. As little as 45% by weight talc may be used in separators containing calcium or zirconium salts.

PTFE-Bound talc separators for secondary zinc alkaline batteries

An ion permeable material particularly useful for electrode separators. The material is a uniform mixture of 30 to 70% by weight colloidal size asbestos fibers and 20 to 40% by weight unsintered fine polytetrafluoroethylene fibers, bonded together with uniformly dispersed particles of a fluorinated ethylene-propylene copolymer comprising about 5 to 15% by weight of the material. Colloidal size particles of an alkaline earth metal oxide are dispersed throughout the material. The material is initially prepared in a modified paper making process and then heated to a temperature high enough to fuse the fluorinated ethylene-propylene copolymer but not high enough to sinter the polytetrafluoroethylene fibers. An improved zinc-air hybrid fuel cell and an improved silver oxide-zinc secondary battery are made possible with electrode separators such as described herein.

Electrochemical cell electrode separator and method of making it and

In accordance with a preferred embodiment of this invention, the polarization or overvoltage of a carbon black-based air cathode is significantly reduced by adding from 1 to 5 percent, by weight based on the total carbon composition, of carbon derived from poly(vinylidene chloride) (hereinafter PVdC) to the carbon black, prior to the formation of the electrode. To accomplish this, the porous and particulate carbon black is initially blended with a solution of PVdC; the resulting blend is dried, and then dehydrochlorinated and baked at a temperature in the range of from 900.degree. C. to 1,100.degree. C. The electrocatalytic layer of the cathode is then prepared from this tailored carbon substrate.

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Utica, MI, United States of America

Romeo R Witherspoon