Lead-acid battery separator having enhanced stiffness

摘要

A lead-acid battery separator comprised of a porous membrane substrate having a front surface and a back surface and said front surface having a plurality of ribs. To enhance the substrate's stiffness, one or more coatings of a stiffening material may be adhered to the ribs on the substrate's surface.

主权项

1. A lead-acid battery separator comprising:
a porous polyolefin membrane substrate having a flat microporous backweb with a front surface and a back surface; said front surface having a plurality of machine direction ribs protruding from the backweb; and a coating of a stiffening material adhered to said ribs, said stiffening material being selected from the group consisting of: sodium silicate, acrylic co-polymers, polyvinyl alcohols, inorganic salts, and combinations thereof, wherein said adhered stiffening material on said ribs provides an increase in stiffness in at least one of the machine direction or cross machine direction when compared to said porous polyolefin membrane substrate without said coating.