Non-sintered metallic overcoated non-woven fiber mats

Claim 2

A non-woven fiber mat having a multiplicity of pores which extend continuously from one surface of said mat to the other surface comprising: (A) A multiplicity of electrocoatable fibers overlaid and intersecting substantially within the same two dimensional plane; (B) A fibrillated binder in a structurally sup­portive amount dispersed within said mat wherein said binder fibrils contact said electrocoatable fibers; and (C) A substantially uniform metallic overcoat covering said electrocoatable fibers and at least partially incorporating within said overcoat said binder at the sites where said binder contacts said electrocoatable fibers.

Claim 3

The mat of Claim 1 wherein the majority of said fibrils of (B) contact said electrocoatable fibers substan­tially in dimensional planes angular to said two dimensional plane of (A).

Claim 4

The mat of Claim 1 wherein said electrocoatable fibers are randomly overlaid and randomly intersecting.

Claim 5

The mat of Claim 1 wherein said fibrils contact said electrocoatable fibers by wrapping around said electro­coatable fibers.

Claim 6

The mat of Claim 1 wherein said electrocoatable fibers are selected from the group consisting of: (a) metal coated electrically conductive fi­bers; (b) electrically conductive fibers; (c) metal coated non-conductive fibers; and (d) mixtures thereof.

Claim 7

The mat of Claim 5 wherein said metal of said metal ccated fibers of (a) and (c) is selected from the group consisting of: nickel, iron, cobalt, platinum, gold, silver, copper, palladium, aluminum, lead, zinc, tim, chromium, cad­mium, ruthenium, and alloys comprising at least one metal thereof as a main component; wherein said electrically con­ductive fibers of (a) and (b) are selected from the group consisting of: carbon fibers, graphite fibers, activated carbon fibers, pitch-based graphite fibers, intercalated graphite fibers, boron, silicon carbide, and mixtures there­of; and wherein said non-conductive fibers of (c) are selected from the group of fibers consisting of: polyesters, poly­olefins, acrylics, polyamides, copolymers thereof, glass, ceramic and mixtures thereof.

Claim 8

The mat of Claim 6 wherein said metal is nickel.

Claim 9

The mat of Claim 5 wherein said metal coated electrically conductive fibers are nickel coated carbon fi­bers or nickel coated graphite fibers; wherein said elec­trically conductive fibers are carbon fibers or graphite fibers; wherein said non-conductive fibers are acrylic fi­bers; and wherein said binder is selected from the group of fibers consisting of: acrylics, polyfluorocarbons, copoly­mers thereof and mixtures thereof.

Claim 10

The mat of Claim 8 wherein said binder is acrylic fibers.

Claim 11

The mat of Claim 1 wherein said electrocoatable fibers are present in an amount of about 80 to about 98 weight percent and said binder is present in an amount of about 2 to about 20 weight percent, said weight percents being based on the total weight of said electrocoatable fibers and said binder.

Claim 12

The mat of Claim 1 wherein said electrocoatable fibers are present in an amount of about 88 to about 96 weight percent and said binder is present in an amount of about 4 to about 12 weight percent, said weight percents being based on the total weight of said electrocoatable fibers and said binder.

Claim 13

The mat of Claim 1 wherein said electrocoatable fibers have lengths up to about 7mm.

Claim 14

The mat of Claim 1 wherein said electrocoatable fibers have lengths within the range of about 0.5 mm to about 7 mm.

Claim 15

The mat of Claim 1 wherein said electrocoatable fibers have diameters within the range of about 3 microns to about 15 microns.

Claim 16

The mat of Claim 1 wherein said binder fibrils have diameters up to about 5 microns.

Claim 17

The mat of Claim 1 wherein said metallic overcoat is up to about 3 microns thick.

Claim 18

The mat of Claim 1 wherein the metal of said metallic overcoat is selected from the group consisting of: nickel, iron, cobalt, platinum, gold, silver, copper, palla­dium, aluminum, lead, zinc, tin, chromium, cadmium, rutheni­um, and alloys comprising at least one metal thereof as a main component.

Claim 19

The mat of Claim 1 wherein: said electrocoatable fibers are randomly overlaid and ran­domly intersecting; have lengths within the range of about 0.5 mm to about 7 mm; are selected from the group consisting of metal coated electrically conductive carbon or graphite fibers; electrically conductive carbon or graphite fibers; metal coated non-conductive acrylic fibers, and mixtures thereof; have diameters within the range of about 3 microns to about 15 microns; and are present in an amount of about 88 to about 96 weight percent, based on the total weight of said electrocoatable fibers and said binder; said binder is selected from the group consisting of acrylic fibers, polyfluorocarbons and mixtures thereof; the majority of the fibrils of said binder contact said electrocoatable fibers substantially in dimensional planes angular to said two dimensional plane of said electrocoatable fibers; the di­ameter of said fibrils is up to about 5 microns; and said binder is present in an amount of about 4 to about 12 weight percent, based on the total weight of said electrocoatable fibers and said binder; said metallic overcoat is up to about 3 microns thick with said overcoat at least partially incorporating within said over­coat said binder at the sites where said binder contacts said electrocoatable fibers; and said metal of said metal coated fibers and of said metallic overcoat, is selected from the group consisting of: nickel, iron, cobalt, platinum, gold, silver, copper, palladium, aluminum, lead, zinc, tin, chromium, cadmium, ruthenium, and alloys comprising at least one metal thereof as a main com­ponent.

Claim 20

The mat of Claim 18 wherein said electrocoatable fibers are nickel coated carbon or graphite fibers present in an amount of about 94 weight percent and said binder is present in an amount of about 6 weight percent, said weight percents being based on the total weight of said electrocoatable fibers and said binder, and said overcoat is nickel; or said electro­coatable fibers are carbon or graphite fibers present in an amount of about 90 weight percent and said binder is present in an amount of about 10 weight percent, said weight percents being based on the total weight of said electrocoatable fibers and said binder; and said binder is a copolymer of at least about 89% by weight acrylonitrile and up to about 11% by weight methyl methacrylate.

Claim 21

A method of producing a non-woven fiber mat of Claim 1 comprising: (I) intimately admixing said electrocoatable fibers of (A) and said fibrillated binder of (B) with a suspending liquid and a floccu­lating agent until a substantially uniform well dispersed mixture is obtained; (II) adding said mixture of (I) to a suitable container having a support structure and outlets for controlling removal of said sus­pending liquid, said container having added thereto a minor amount of said suspending liquid before the addition of said mixture of (I); (III) adding additional suspending liquid whereby substantially all the volume of said con­tainer has been filled; (IV) stirring the mixture in said container; (V) allowing said mixture of (IV) to settle; (VI) removing a substantial amount of said sus­pending liquid whereby a minor amount of suspending liquid remains above the formed mat sufficient to allow the addition of at least one sheet of absorbing and/or porous material to be placed in the remaining sus­pending liquid without adversely disturbing the formed mat; (VII) adding at least one sheet of absorbing and/or porous material to said remaining suspending liquid; (VIII) removing said remaining suspending liquid thereby causing said absorbing and/or porous material to make contact with the surface of said mat; (IX) removing said mat from said container; (X) placing said mat in a drum dryer, optionally between sheets of absorbing and/or porous material; (XI) optionally, repeating (X) wherein the ab­sorbing and/or porous material is changed; (XII) optionally, drying said mat in a convection oven; (XIII) optionally, treating said mat with a wetting solution; (XIV) placing said mat in an electrolyte solution, optionally having a wetting solution added thereto, at the cathode position substan­tially symmetrically between two anodes comprising the metal to be deposited or two insoluble anodes; (XV) applying a current; and (XVI) providing bulk electrolyte solution to both sides of said mat.

Claim 22

The method of Claim 20 wherein said suspending liquid is deionized water; said mixture of (V) is allowed to gravity settle; said wetting solution of (XIV) is present in said electrolyte solution; and the direction of flow of the electrolyte solution is periodically reversed.

Claim 23

The method of Claim 20 wherein said mat of (XIII) is treated with a wetting solution.

Claim 24

The method of Claim 21 wherein said drum dryer of (X) is a steam heated drum dryer and said mat is thereafter dried in a convection oven.

Claim 25

The method of Claim 23 wherein said heated drum dryer is at a temperature of about 99°C to about 101°C and said convection oven is at a temperature of about 70°C.

Claim 26

The method of Claim 22 wherein said suspending liquid is deionized water; the mixture of (V) is allowed to gravity settle; and the direction of flow of the electrolyte solution is periodically reversed.

Claim 29

The method of Claim 26 wherein said mat of (I) is treated with a wetting solution, and the direction of flow of electrolyte solution is periodically reversed.

Claim 30

The method of Claim 26 wherein said wetting agent is present in said electrolyte solution, and the direction of flow of electrolyte solution is periodically reversed.

Claim 31

A battery electrode comprising a non-woven fiber mat of Claim 1.

Claim 32

A battery comprising at least one battery elec­trode of Claim 29.