Battery separator with mud rest protectors

A porous, acid-resistant battery separator for use in a lead acid battery having a cell compartment that includes planar mud rests that extend along and upward from the bottom of the cell compartment, the planar mud rests configured to prevent contact between an electrode and a mud precipitate that is formed during operation of the lead acid battery and that accumulates at the bottom of the cell compartment, the battery separator comprising:

• a backweb having an upper planar surface and a lower planar surface separated by a backweb thickness;
• multiple spaced-apart major ribs extending a major rib height above the backweb and longitudinally disposed along the length of one of the upper planar surface or the lower planar surface to facilitate electrode spacing and to provide a space in which an electrolyte can reside;
• multiple submini-ribs extending a submini-rib height above the backweb and longitudinally disposed along the length of one of the upper planar surface or the lower planar surface such that a number of the multiple submini-ribs are positioned between adjacent major ribs, the submini-ribs having a submini-rib thickness that is greater than the backweb thickness, the submini-rib thickness and the number of and spacing between ones of the submini-ribs positioned between adjacent major ribs cooperating to cause the submini-ribs to be a primary point of contact between the battery separator and the mud rests and thereby to delay the formation of a wear area in the battery separator during operation of the lead acid battery.