Additive for producing positive active compositions for lead accumulators

摘要

An additive for producing positive active compositions for lead accumulators based on finely divided 4-basic lead sulphate having an average particle size of less than about 3 μm and also finely divided silica, where the additive additionally contains red lead (2PbO.PbO2), is described. The finely divided silica prevents, in particular, agglomeration of the particles of the 4-basic lead sulphate, while the red lead leads to an optimized distribution of all constituents of the additive in the battery paste. The use of red lead also gives a cost advantage. Despite the replacement of part of the 4-basic lead sulphate by red lead, the properties achieved in the later use in battery operation are no worse. Thus, the batteries display, for example, improved charging behavior and a higher high-current discharging stability. The invention further relates to the use of the additive according to at least one of claims 1 to 15 for producing positive active pastes for lead accumulators, in particular for lead accumulators having a high total discharging stability.

主权项

1. An additive for production of positive active compositions for lead accumulators, the additive being based on finely divided tetrabasic lead sulphate having a mean particle size of less than about 3 μm and finely divided silica, wherein the additive comprises red lead (2PbO, PbO2), and wherein the mean particle size of the red lead is less than about 1.5 μm and/or there are less than 2.2 mol of PbO per 1 mol of PbO2 in the red lead.