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Why does recycled battery lead often contain antimony?

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Metallurgy — lead processing A zinc-lead blast furnace and lead-splash condenser. This technology is utilized mainly for producing zinc while managing both lead and zinc from raw materials, a technique that was highly influential in 20th-century smelting.

Recycled battery lead often contains antimony because it was intentionally added to the original lead-acid storage batteries during their manufacture.12

In the production of these batteries, antimony is alloyed with lead to provide essential hardness and strength to the battery's grids and terminals. Because this antimony remains present in the battery components after they are discarded, it persists in the scrap material during the recycling process. When these batteries are processed, the recovered lead bullion typically retains these small percentages of antimony. While some refining processes can remove antimony to produce pure lead or specific lead-calcium alloys, much of the secondary lead containing antimony is simply refined and resold to battery manufacturers to be reused in the production of new batteries.3214