Additives to lead±acid battery active materials and components are categorized as physical and chemical attribute additives. Separators are equally divided into two classes, those that have inner skeletal structures, commonly made of mixtures of polymers and precipitated silica, and those that are made of loose ®bers. Separator additives are also brie¯y discussed. Both physical and chemical impacts of active material additives on separators are considered. With the noted exception of negative plate expanders, very little interaction has been reported thus far between active material additives and separators. . | ELSEVIER Journal of Power Sources 95 2001 255-263 Battery additives any influence on separator bahavior Antonio L. Ferreira Hollingsworth Vose Co. Battery Separators Business Unit 219 Townsend Rd. West Groton MA 01472-0168 USA Abstract Additives to lead-acid battery active materials and components are categorized as physical and chemical attribute additives. Separators are equally divided into two classes those that have inner skeletal structures commonly made of mixtures of polymers and precipitated silica and those that are made of loose fibers. Separator additives are also briefly discussed. Both physical and chemical impacts of active material additives on separators are considered. With the noted exception of negative plate expanders very little interaction has been reported thus far between active material additives and separators. This question should be further investigated in the light of the growing importance of additives in improving the performance of the lead-acid battery. 2001 Elsevier Science . All rights reserved. Keywords Battery additive Skeletal structure separator Fiber structure separator Dendrite preventive additive DPA Physical attribute additive Chemical attribute additive 1. Introduction Some of the first types of separators used in lead-acid batteries were wood separators. Over many years of use battery experts began to understand the bene cial influence of some of the components of these wood separators. Thus the rst additive to battery active materials was pulverized wood added to the negative paste mixes. The earliest patent in this domain was given in 1919 1 . This rst active material additive was intended to preserve the spongy lead structure of negative plates. Besides pulverized wood other materials as diverse as lamp black barium sulfate powdered charcoal wood flour and other assorted wood extracts were used as additives. Additives to the negative active material became a major topic once lead-acid batteries stopped using wood
