Battery separators

Abstract

A battery separator is described that comprises a nonwoven, pre-strengthened by needling and calibrated with a calender, which is final-strengthened with an acid-resistant binder. The battery separators have a uniform thickness, are not hairy, and can be used in a versatile manner, in particular also for tubular pockets.

1 . Battery separator, comprising a nonwoven pre-strengthened by needling and calibrated with a calender, which is final-strengthened with an acid-resistant binder.  
     
     
         2 . Batter separator according to  claim 1 , characterized in that the nonwoven is a polyester nonwoven.  
     
     
         3 . Battery separator according to  claim 2 , characterized in that the nonwoven consists of manganese-free polyester fibers.  
     
     
         4 . Battery separator according to at least one of  claims 1  to  3 , characterized in that the nonwoven consists of endless fibers.  
     
     
         5 . Battery separator according to  claim 4 , characterized in that the nonwoven is a spun-bonded nonwoven.  
     
     
         6 . Battery separator according to at least one of  claims 1  to  5 , characterized in that the fabric weight of the nonwoven, including the binder, is 80 to 180 g/m 2 .  
     
     
         7 . Battery separator according to  claim 6 , characterized in that the fabric weight, including binder, is 100 to 150 g/m 2 .  
     
     
         8 . Battery separator according to at least one of  claims 1  to  7 , characterized in that the nonwoven is needled with a stitch density of 30 to 60 stitches per cm2.  
     
     
         9 . Battery separator according to at least one of  claims 1  to  8 , characterized in that the nonwoven is final-strengthened with an acrylate binder.  
     
     
         10 . Battery separator according to  claim 9 , characterized in that the nonwoven contains 5 to 25 weight acrylate binder.  
     
     
         11 . Battery separator according to at least one of  claims 1  to  10 , characterized in that the nonwoven has been calibrated with a calender with a temperature of 170 to 200° C.  
     
     
         12 . Battery separator according to at least one  claims 1  to  11 , characterized in that the battery separator is fabricated in the form of a tubular pocket.  
     
     
         13 . Method for producing battery separators, characterized in that an endless filament nonwoven is produced by spinning polymers, the nonwoven is pre-strengthened using needles, the nonwoven, pre-strengthened in this way, is calibrated using a calender and is then final-strengthened with an acid-resistant binder.  
     
     
         14 . Method for producing battery separators according to  claim 13 , characterized in that an endless filament nonwoven is produced by spinning polyester material, the nonwoven is pre-strengthened using needles, the nonwoven, pre-strengthened in this way, is calibrated using a calender and is then final-strengthened with an acid-resistant binder.  
     
     
         15 . Method according to  claim 14  for producing battery separators, characterized in that an endless filament nonwoven is produced by spinning polyethylene terephthalate, the nonwoven is pre-strengthened using needles, the nonwoven, pre-strengthened in this way, is calibrated using a calender and is then final-strengthened with an acid-resistant binder.  
     
     
         16 . Method according to one of claims  13 - 15 , characterized in that the calibration is performed using a calender with a temperature of 170 to 200° C.  
     
     
         17 . Method according to at least one of  claims 13  to  16 , characterized in that the needling is performed with a stitch density of 30 to 60 stitches per cm 2 .  
     
     
         18 . Method according to at least one of  claims 13  to  17 , characterized in that a cross-linking acrylate binder is used as acid-resistant binder.  
     
     
         19 . Use of the battery separators according to at least one of  claims 1  to  12  or produced by a method according to at least one of  claims 13  to  18  in lead accumulators.