Influence of compression on microfiber glass separator and effect of orientation on battery performance

As recombinant valve-regulated Pb-acid batteries continue to find acceptance as a replacement for flooded Pb-acid batteries, there is a need to understand the role of the microfiber glass mat which is used as the separator and acid reservoir in these batteries. Wicking experiments are instructive and can serve as a valuable analysis tool. In this paper, the effects of compression and thickness on the wicking rates are addressed and presented. The effects of thickness and compression on the acid uptake of the mat material were measured and data on specific gravity segregation are presented. The effects on battery capacities of cycling and subsequent varied recharges are included. The major characteristics of the absorbent glass mat separators tested provided a family of curves which shows retardation of the wicking rates with increasing compression. The cyclic capacity data as a function of battery orientation indicate that large power batteries could possibly benefit from cells constructed with plates in a horizontal position (parallel to the horizon)