Patent ID: 6495286
Filing Date: 2002-12-17
Classification: H01M,Y02E

Abstract:
A valve regulated lead/sulfuric acid recombinant storage battery comprising a plurality of lead plates in a closed case, a fibrous sheet plate separator between adjacent ones of said plates, and a body of a sulfuric acid electrolyte absorbed by each of said separators and maintained in contact with each of the adjacent ones of said plates, each of said separator sheets comprising a mass of intermeshed glass fibers substantially all of which have a fiber diameter not greater than about 20 &mgr;m, and at least 5 percent w/w of which have a fiber diameter less than 1 &mgr;m, and, distributed through the glass fibers, from 0.2 percent w/w to 20 percent w/w of beaten cellulose fibrils from a slurry which has a Canadian freeness not greater than 650 cc, said freeness being sufficiently low such that the battery has a service life, when cycled, at least 10 percent greater than a battery made with an otherwise identical separator where glass fibers having an average diameter greater than 1 &mgr;m replace the cellulose fibrils.