What Standards Must Battery Factory Wastewater Meet Before Discharge?

Battery manufacturing is a water-intensive industry. Electrode preparation, electrolyte mixing, formation processes, and equipment washing all generate wastewater containing heavy metals, acids, alkalis, and high concentrations of organic compounds. In China, these discharges are primarily regulated by the national standard GB 30484?2013, formally titled the Emission Standard of Pollutants for Battery Industry, which took effect on March 1, 2014.

Direct vs. Indirect Discharge

The standard sets different limits depending on where the wastewater ends up:

Direct discharge applies when treated wastewater is released directly into rivers, lakes, or other natural water bodies. These limits are stricter.

Indirect discharge applies when wastewater is pretreated on?site before being sent to a municipal or industrial centralized sewage treatment plant for further processing. These limits are somewhat more lenient.

For example, the chemical oxygen demand (COD) limit is 60?mg/L for direct discharge, compared with 100?mg/L for indirect discharge. Total lead must not exceed 0.5?mg/L in direct discharge but can be up to 1.0?mg/L in indirect discharge. Other common limits include:

pH: 6–9

Suspended solids (SS): ≤?140?mg/L

Ammonia nitrogen (NH??N): ≤?30?mg/L

These values illustrate the principle of pretreatment before pipe?in — even indirect dischargers must remove concentrated heavy metals or organic pollutants before sending wastewater to municipal networks.

Key Pollutants Vary by Battery Type

Different battery technologies produce different characteristic pollutants, and the standard applies separate limits for each category.

Lead?acid batteries: The primary concerns are lead (Pb), cadmium (Cd), and COD. Total lead is capped at 0.5?mg/L. In addition, an even stricter monitoring point — the “workshop wastewater treatment facility outlet” — must also meet the 0.5?mg/L lead limit.

Lithium ion batteries: Characteristic heavy metals include nickel (Ni), cobalt (Co), and manganese (Mn). Their respective limits are 0.1?mg/L, 0.05?mg/L, and 0.5?mg/L. Lithium battery waste streams also often contain high concentrations of ammonia?nitrogen, for which dedicated treatment and reuse specifications have been developed.

Zinc?manganese batteries: The primary metals to control are mercury (Hg), zinc (Zn), and manganese (Mn), with manganese limits varying depending on the discharge pathway.

Nickel?cadmium (Ni?Cd) and nickel?metal hydride (Ni?MH) batteries: The key indices are cadmium, nickel, and COD.

Special Limits in Key Regions