Battery plate retainer mat and method of manufacture

Claim 2

BATTERY PLATE RETAINER MAT OR SEPARATOR CONSISTING ESSENTIALLY OF: A. A FIRST CONTINUOUS ELECTROLYTE PERMEABLE LAYER OF MATTED ELECTRICALLY INSULATIVE AND ELECTROLYTE RESISTANT FIBERS AND CONTAINING ESSENTIALLY NO BINDER MATERIALS, B. A SECOND ELECTROLYTE-PERMEABLE LAYER OF ELECTROLYTE RESISTANT FIBERS BOUND TOGETHER WITH A BINDER, C. SAID FIRST LAYER BEING ATTACHED TO SAID SECOND LAYER SUCH THAT A MAJOR SURFACE OF SAID FIRST LAYER CONTACTS A MAJOR SURFACE OF SAID SECOND LAYER, WITH ATTACHMENTS SELECTIVELY SPACED OVER AT LEAST ONE OF THE MAJOR SURFACES OF SAID FIRST AND SECOND LAYERS WHEREBY ONLY PORTIONS OF SAID FIRST LAYER ARE ATTACHED TO ADJACENT PORTIONS OF SAID SECOND LAYER.

Claim 3

The article of claim 1 wherein said second layer is higher in density, stronger, and thinner than at least the unattached portions of said first layer.

Claim 4

The article of claim 2 wherein the diameters of the fibers in said first layer and the thickness of said first layer are sufficient to act as a barrier to particles of battery plate paste and particles frequently present in the electrolyte of a functioning wet-cell battery.

Claim 5

The article of claim 3 wherein the diameters of the fibers in said first layer are less than about 13 microns.

Claim 6

The article of claim 4 wherein the fibers in said first layer comprise material selected from the group consisting of natural and synthetic organic materials, glasses, ceramic materials and combinations thereof.

Claim 7

The article of claim 5 wherein the fibers in said first layer comprise material selected from the group consisting of polypropylene, chemical grade glass, alumina, alumina-silica and combinations thereof.

Claim 8

The article of claim 5 wherein said first layer contains an effective amount of an anti-static agent.

Claim 9

The article of claim 7 wherein the antistatic agent is mineral oil.

Claim 10

The article of claim 1 wherein the thickness of said second layer is within the range of about 0.01 to about 0.030 inches.

Claim 11

The article of claim 9 wherein the fibers in said second layer comprise material selected from the group consisting of natural and synthetic organic materials, glasses, ceramic materials and combinations thereof.

Claim 12

The article of claim 10 wherein the fibers in said second layer comprise material selected from the group consisting of polypropylene, chemical grade glass, alumina, alumina-silica and combinations thereof.

Claim 13

The article of claim 9 wherein said second layer contains an effective amount of binder within the range of about 5 to about 20% by weight.

Claim 14

The article of claim 12 wherein said binder is selected from the group consisting of styrene resins, acrylic resins, urea formaldehyde resins and combinations thereof.

Claim 15

The article of claim 1 wherein the attachments are soluble in an electrolyte.

Claim 16

The article of claim 14 wherein the attachments are stitches.

Claim 17

The article of claim 15 wherein the stitches comprise threads of a synthetic resin.

Claim 18

The article of claim 1 whereIn the attachments are spots or strips of adhesive, said adhesive being essentially not deteriorated by an electrolyte.

Claim 19

A battery plate retainer mat or separator consisting essentially of: a. a first continuous electroylyte-permeable layer of matted electrolyte resistant and electrically insulating fibers having diameters of less than about 13 microns, said first layer being sufficiently thick to act as a barrier to particles of a battery plate paste and to particles frequently present in an electrolyte of a functioning wet-cell battery and being essentially free of a binder material; b. a second electrolyte-permeable layer of electrolyte resistant fibers, said second layer having a thickness of up to about 0.03 inches, the fibers in said second layer being bonded together with a binder that is essentially non-deteriorated by an electrolyte; c. said first continuous layer being attached to said second layer only by spaced attachments, said attachments being stitches, said first layer being attached to said second layer such that a major surface of said first layer is in contact with a major surface of said second layer.

Claim 20

A battery plate retainer mat or separator consisting essentially of: a. a first continuous electroylyte-permeable layer of matted electrolyte resistant and electrically insulating fibers having diameters of less than about 13 microns, said first layer being sufficiently thick to act as a barrier to particles of a battery plate paste and to particles frequently present in an electrolyte of a functioning wet-cell battery and being essentially free of a binder material; b. a second electrolyte-permeable layer of electrolyte resistant fibers, said second layer having a thickness of up to about 0.03 inches, the fibers in said second layer being bonded together with a binder that is essentially non-deteriorated by an electrolyte; c. said first continuous layer being attached to said second layer only by spaced attachments, said attachments being stitches, said first layer being attached to said second layer such that a major surface of said first layer is in contact with a major surface of said second layer.

Claim 21

The article of claim 18 wherein said first layer and said second layer contain chemical grade glass fibers.

Claim 22

The article of claim 19 wherein said first layer contains an effective amount of an anti-static agent.

Claim 23

The article of claim 19 wherein said stitches are soluble in an electrolyte.

Claim 24

The article of claim 18 wherein said first layer and said second layer contain synthetic resin fibers.

Claim 27

The method of claim 23 further comprising cutting said layered composite to a desired size.

Claim 28

The method of claim 24 wherein said layered composite is only cut transverse to the length thereof.

Claim 29

The method of claim 23 wherein the attaching step is achieved by stitching said first layer to said second layer with a material that is soluble in a conventional battery electrolyte.

Claim 30

The method of claim 23 wherein an adhesive is applied to spaced-apart areas of at least one of said major surfaces before said first and second layers are brought together.

Claim 31

A battery containing electrolyte and plates therein and further containing at least one battery plate retainer mat or separator as claimed in claim 18 having the first continuous fibrous layer in contact with either a battery plate or a layer of battery paste thereon.