Construction of sealed starter batteries for use in lorries - features porous separators of plastic fibre resulting in a recombination efficiency of 30-50 per cent

摘要

The lead-acid battery with gas-recombination consists of multiple cells with at least one negative (8) and one positive (6) electrode each sepd by a porous material (10) which has been impregnated with acid. The feature is that the separator (10) has pores with a dia of 10-50 micron, pref 10-30 micron, and that the acid content is such that all pores are filled with acid. The cells also contain porous membranes, with a pore size of 2-10 micron, between the ends of the separators and the walls of the battery. The separators are pref made of a felt consisting of plastic fibres of the type : polyethylene, polyester, polyterephthalate and polyvinyl-resin. The metal electrodes used are an Sb-free alloy of Pb, featuring a Ag-content of 0.005-0.02 wt% or Co with a content of 0.005-0.03 wt%. The electrolyte pref contains dissolved metal salts or a mixt from the gp : Ag, Co, Sb, Ni in a concn of 0.055-0.03 wt%. USE/ADVANTAGE - The battery can function with a lower gas recombinationm efficiency because it spends a small part of its oeprational life, from 2-3% to 20-40%, being charged up. For the rest of the time the battery generates only small amts of gas. The batteries can be made with simpler lid construction without requiring a liquid trap and thinner walls, because the gas-pressure is lower. The replacement of glass-fibres by plastic fibres also reduces cost.