Method of making a composite electrode

Claim 1

A method of making a composite electrode for a storage battery or the like which comprises the steps of: applying to opposite sides of a metal support, formed with a surface distribution of throughgoing openings, respective flexible screen-like synthetic-resin openworks of filamentary material to form a resulting three-layered assembly; sandwiching the entire resulting assembly between a pair of rigid ultrasonic welding plates having juxtaposed surfaces substantially coextensive with said openworks; applying a mechanical pressure of substantially 2 to 20 g/cm 2 to said assembly by pressing said plates toward one another to deflect said openworks and simultaneously subjecting same to ultrasonic welding by applying ultrasonic energy at a frequency of about 20,000 Hz across said plates for a period of about 1 to 2 seconds and only long enough to bond the filaments thereof together through said openings without bonding said filaments to the metal support, said openworks forming interstices on opposite sides of said support; thereafter placing an active mass in said interstices and in contact with said support; and fusing, by the application of heat and pressure, respective fine-porous flexible cover layers of synthetic resin to said openworks, the active mass being deposited in said interstices before said cover layers are emplaced thereon whereby the active mass is densified by the pressure subsequently applied to said cover layers.

Claim 2

A method of making a composite electrode for a storage battery or the like which comprises the steps of: applying to opposite sides of a metal support, formed with a surface distribution of throughgoing openings, respective flexible screen-like synthetic-resin openworks of filamentary material to form a resulting three-layered assembly; sandwiching the entire resulting assembly between a pair of rigid ultrasonic welding plates having juxtaposed surfaces substantially coextensive with said openworks; applying a mechanical pressure of substantially 2 to 20 g/cm 2 to said assembly by pressing said plates toward one another to deflect said openworks and simultaneously subjecting same to ultrasonic welding by applying ultrasonic energy at a frequency of about 20,000 Hz across said plates for a period of about 1 to 2 seconds and only long enough to bond the filaments thereof together through said openings without bonding said filaments to the metal support, said openworks forming interstices on opposite sides of said support; thereafter placing an active mass in said interstices and in contact with said support; and fusing, by the application of heat and pressure, respective fine-porous flexible cover layers of synthetic resin to said openworks, the active mass being deposited in said interstices before said cover layers are emplaced thereon whereby the active mass is densified by the pressure subsequently applied to said cover layers.