The battery manufacturing process requires the use of concentrated metal nitrate solutions that result in dilute waste solutions and metal precipitates. Both nickel and cadmium are used in large quantities, and sometimes cobalt is used as an additive. The cobalt used in the creation of the most energy dense lithium-ion batteries is poisonous and extremely carcinogenic. The lithium-iron phosphate used in lower energy density batteries is better in terms of its carcinogenic effect, but might be worse in terms of the impact on the biosphere.
Exposure to lead is also a primary health concern in battery manufacturing. Any operation in which battery plates, lead scrap, or oxide is handled may be a significant source of lead exposure. Airborne dispersion of lead dust (which settles on equipment, floors and other surfaces) via cross-drafts, pedestrian and vehicular traffic, and dry sweeping, may be an additional source of lead exposure.
Battery manufacturing plants under federal jurisdiction are required to comply with Federal OSHA occupational safety and health standards for general industry (29 CFR 1910).