The role of silica in separator technology

Agenda for
5-9 September

Dr Richard Pekala
Chief Technology Officer, ENTEK International LLC
Silica is a major component of separators used in Pb-acid batteries. In this paper, we review how silica is manufactured in both powder and fiber form, and then we discuss the influence of key characteristics such as particle size, oil absorption, surface area, and fiber diameter on separator processing and properties. We will examine the chemistry-structure-property relationships of three different separators, which are polyethylene, synthetic pulp and absorptive glass mat, as they relate to battery performance (e.g., cycling, impedance).

Finally, we will demonstrate the importance of controlling particle size on separator homogeneity and how under certain conditions, silica can be dissolved into the acid electrolyte of a Pb-acid battery.


Rick Pekala has a Sc.D. degree in polymeric materials from the Massachusetts Institute of Technology. After periods of research at the Lawrence Livermore National Laboratory and at PPG Industries, he joined ENTEK in 1999 where he assisted with the commercialization of various new products such as lithium-ion and lead‒acid battery separators, and electrically conductive porous film. Rick is currently the Chief Technology Officer for ENTEK International LLC.