Spent batteries containing hazardous constituents — including lead-acid and lithium-ion scrap — may be regulated as hazardous waste under RCRA. Importers must determine whether the material qualifies for a universal waste exemption or requires a full hazardous-waste import permit. Transboundary movements of hazardous waste are also subject to Basel Convention controls, which EPA administers through its import/export notification process.

The NES (not elsewhere specified) designation is a residual classification — it applies only when no more specific heading covers the article. Importers should first exhaust more specific electrical and electronic headings before defaulting to NES. A detailed technical description of the part's function, construction, and end-use on the commercial invoice helps customs officers and brokers identify the correct heading and reduces the risk of a post-entry reclassification.