Greatbatch Ltd.

Brian D Panzer

Kenneth B Talamine

William C Thiebolt

Xiangyang Steve Dai

Kenneth L Grubb

William Thiebolt, Iii

A new weld configuration is used to obtain a robust and consistent resistance weld between the tabs of an anode current collector and the casing of an electrochemical cell. This is done by adding a resistive transferable electrode tip between at least one of the welding electrodes, preferably the movable welding electrode, and the stacked parts that are being joined together. The purpose of the transferable electrode tip is to generate a sufficient amount of heat during the welding process so that the stacked parts are joined together without adding any product functionality. In one embodiment of the present invention, the transferrable electrode tip is a stainless-steel ball, the stacked anode current collector tabs are of nickel, and the cell casing is of stainless-steel.

Transferable electrode tip for resistance welding an anode tab to the casing of an electrochemical cell

An electrochemical cell comprising an electrode assembly formed from an elongate anode that is folded into a serpentine configuration with a plurality of cathode plates interleaved between the folds is described. To make a robust and secure connection of the respective cathode tabs to a cathode terminal, the tabs are folded into an overlapping and stacked relationship. The proximal end of a metal strip is wrapped around the stacked cathode tabs and then a laser is used to weld through all layers of the metal strip and each of the bound cathode tabs. The laser welds are visible from the opposite side of the thusly formed strip-shaped hoop surrounding the stacked cathode tabs from which the laser beam first contacted the assembly. This provides the welding engineer with a visual indication that the welded connection of the metal strip-shaped hoop to the stacked cathode tabs is robust and structurally sound.

Electrochemical cell having a serpentine anode with a plurality of interleaved cathode plates having extending tabs stacked and connected to each other by a welded surrounding metal hoop

Improved methods for manufacturing electrode active tapes, including blanks/plates with essential homogeneity for consistently more reliable performing electrodes for electrochemical cells, and with lower rates of off-specification material, by forming an electrode active mixture; adjusting the solids content to form a filter cake mix; crumbling the filter cake into particles and performing at least one calendering step at a calendering station having a nip zone while applying a force to the particles axially with the direction of movement of the particles to compact the particles in the nip zone for more even presentation during calendering.

Electrode active blanks and methods of making

The present invention is directed to calendaring an electrode active admixture, such as of a transition metal oxide, and particularly silver vanadium oxide, into an electrode structure. To obtain electrode structures of a desired low basis weight requires calendaring a paste of the active material into a first sheet tape, which is subsequently subjected to secondary and ternary calendering steps. Secondary calendaring is performed in a direction reverse or orthogonal to that used to form the initial sheet tape. The final calendaring step is performed in a third direction aligned 180&#xb0; with respect to the first direction, but with the second structure rotated bottom over top with respect to the orientation that formed the first and second structures. The ternary calendaring step provides for fibrillation of the fluoro-polymeric binder in a direction reverse to the initial direction to form the product low basis weight electrode active structure.

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Williamsville, NY, United States of America

Brian D Panzer