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A process for enhancing chemical stability and corrosion resistance is described for perforated current collectors made by continuous production processes for use in electrochemical cells, including storage batteries such as lead-acid batteries. The process relies on utilizing a strip processing met

A process for enhancing chemical stability and corrosion resistance is described for perforated current collectors made by continuous production processes for use in electrochemical cells, including storage batteries such as lead-acid batteries. The process relies on utilizing a strip processing method, selected from the group of reciprocating expansion, rotary expansion and punching, to perforate the solid metal strip to form a grid or mesh, as a deformation treatment. The perforation-deformation treatment is followed in rapid succession by a heat-treatment to obtain a recrystallized microstructure in the current collector and optionally by quenching to rapidly reduce the temperature to below approximately 80° C. The process yields an improved microstructure consisting of a high frequency of special low &Sgr; CSL grain boundaries (>50%), exhibiting significantly improved resistance to intergranular corrosion and cracking. Perforated current collectors produced with this process from a solid lead-alloy strip exhibit superior growth and corrosion properties when employed as positive grids in a lead-acid battery.

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1. A method of manufacturing a metallic current collector for use in an electrochemical or galvanic cell, comprising the steps of: (i) perforating a solid, flat metal strip using a continuous process that results in deformation of the strip at least locally near the perforations, wherein said deform

1. A method of manufacturing a metallic current collector for use in an electrochemical or galvanic cell, comprising the steps of: (i) perforating a solid, flat metal strip using a continuous process that results in deformation of the strip at least locally near the perforations, wherein said deformation expressed by the ratio of the strip thickness before and after deformation is less than 10%; and (ii) immediately following step (i), annealing the perforated strip at a temperature below the melting point of said metal or metal-alloy to yield a special grain boundary content of at least 50% in deformed portions of the strip; with the proviso that said metal consists of lead or lead alloyed with an element selected from the group consisting of Ca, Sr, Ba, Al, Sn, Ag, Bi, and combinations thereof. 2. The method according to claim 1, wherein said continuous process is a process of reciprocating expansion. 3. The method according to claim 1, wherein said continuous process is a process of rotary expansion. 4. The method according to claim 1, wherein said continuous process comprises punching perforations through said metal strip. 5. The method according to claim 1, wherein said step of annealing is carried out at a temperature between 100 and 300° C. for a duration of between 10 seconds and 20 minutes. 6. The method according to claim 5, wherein said metallic current collector is a lead-acid battery grid. 7. The method according to claim 1, further comprising the step, following step (ii), of quenching said perforated strip. 8. The method according to claim 1, further comprising the step, following step (ii), of cooling the perforated strip to a temperature below 80° C. 9. The method according to claim 1, wherein a strip accumulator is used for feeding said solid, flat metal strip into a perforator in step (i) to eliminate or reduce stoppages in said continuous process. 10. The method according to claim 1, wherein said solid, flat metal strip is heat-treated prior to carrying out step (i). 11. A method of manufacturing a metallic current collector for use in an electrochemical or galvanic cell, comprising the steps of: (i) perforating a solid, flat metal strip using a continuous process that results in deformation of the strip by less than 10% when expressed by the ratio of the strip thickness before and after perforation; and (ii) annealing the perforated strip at a temperature below the melting point of said metal or metal-alloy to yield a special grain boundary content of at least 50% in deformed portions of the strip; with the proviso that said metal consists of lead or lead alloyed with an element selected from the group consisting of Ca, Sr, Ba, Al, Sn, Ag, Bi, and combinations thereof. 12. A method of manufacturing a lead or lead alloy current collector for use in an electrochemical or galvanic cell, comprising the steps of: (i) perforating a solid, flat metal strip using a continuous process that results in deformation of the strip by less than 10% when expressed by the ratio of the strip thickness before and after perforation; and (ii) annealing the perforated strip at a temperature between 100° C. and 300° C. to yield a special grain boundary content of at least 50% in deformed portions of the strip; with the proviso that said metal consists of lead or lead alloyed with an element selected from the group consisting of Ca, Sr, Ba, Al, Sn, Ag, Bi, and combinations thereof. 13. In a process for producing a metallic current collector in the form of a grid or mesh for use in an electrochemical or galvanic cell which comprises the steps of: a) making a deformed strip by perforating a solid flat metal strip using a continuous process that results in deformation of the strip at least locally near the perforations whereby said strip is formed into a grid or mesh configuration having a deformed portion, said deformation, expressed by the ratio of the strip thickness before and after perforation, being less than 10%; b) pasting the deformed strip with an electrochemically active material; c) flash curing the paste; and then d) cutting said pasted deformed strip into individual current collectors; wherein the improvement comprises: an annealing step wherein the deformed strip is annealed prior to pasting by heating the metal of said deformed strip to cause the formation of a a special grain boundary content of at least 50% in said deformed portion; said heat treatment being performed at a temperature below the melting point of said metal for up to 20 minutes with the proviso that said metal consists of lead or lead alloyed with an element selected from the group consisting of Ca, Sr, Ba, Al, Sn, Ag, Bi and combinations thereof. 14. The method according to claim 13, wherein said continuous process is a process of reciprocating expansion. 15. The method according to claim 13, wherein said continuous process is a process of rotary expansion. 16. The method according to claim 13, wherein said continuous process comprises punching perforations through said metal strip. 17. The method according to claim 13, wherein said step of annealing is carried out at a temperature between 100 and 300° C. for a duration of between 10 seconds and 20 minutes. 18. The method according to claim 17, wherein said metallic current collector is a lead-acid battery grid. 19. The method according to claim 13, further comprising quenching said deformed strip after said annealing step. 20. The method according to claim 13, further comprising cooling the deformed strip to a temperature below 80° C. after said annealing step. 21. The method according to claim 13, wherein a strip accumulator is used for feeding said solid, flat metal strip into a perforator in step a) to eliminate or reduce stoppages in said continuous process. 22. The method according to claim 13, wherein said solid, flat metal strip is heat-treated prior to carrying out step a).