Old batteries leak toxins; experts outline safe disposal steps

Discarded household batteries leak heavy metals like cadmium and nickel into soil and water when they reach landfills. Some can also overheat and cause fires in garbage trucks and recycling centers.

Safely disposing of batteries takes just a few steps, and their materials can be recycled into new products, experts say.

Millions of household batteries are discarded yearly in the United States. Though individual batteries are small, their cumulative environmental impact — from mining the metals inside them to the toxins they release when improperly disposed of — makes careful recycling a matter of both environmental and public safety.

Why Battery Disposal Matters

Millions of household batteries are discarded every year in the United States, and many end up in junk drawers or landfills. Dead batteries create real hazards: they leak heavy metals like cadmium and nickel into soil and water, and some can overheat and cause fires in garbage trucks and recycling centers.

“Battery recycling keeps you safe, keeps the waste industry safe, keeps the first responders safe and responsibly sees that battery reach a proper end of life,” said Michael Hoffman, president of the National Waste and Recycling Association.

Safely disposing of batteries takes just a few steps, and once recycled, their materials can be made into new products.

Different Batteries Require Different Handling

Batteries come in different types, each with its own disposal requirements. Alkaline and zinc-carbon batteries — the most common single-use batteries, including AA and AAA sizes — can be safely thrown in household trash in most places. The Environmental Protection Agency still recommends recycling them so their materials can be reused.

Lithium-ion batteries pose a greater hazard. Commonly found in power tools and cordless vacuums, and increasingly in single-use batteries, lithium-ion batteries risk causing fires and leaking toxic gases in garbage trucks and landfills. Several jurisdictions have recognized this danger: New York, Vermont, and Washington, D.C. have enacted special rules for disposing of household and rechargeable batteries.

For batteries that look swollen, cracked, or are leaking, experts recommend contacting your local hazardous waste removal agency rather than dropping them off at a standard recycling location.

Finding a Drop-Off Location

To prepare batteries for recycling, tape their ends or place them in plastic bags to prevent the risk of sparking. Hardware and office supplies stores often accept old batteries. City and state drop-off programs vary by location.

The Battery Network, a nonprofit dedicated to safe battery recycling, provides a searchable database where people can find drop-off locations by ZIP code. “At some point, hopefully among all the other things that we all have in our lives, you can find a convenient drop-off location,” said Todd Ellis of The Battery Network.

Once batteries reach a recycling facility, they are sorted by type and broken down into their essential components — cobalt, nickel, and aluminum among them. These materials are used to make new batteries, stainless steel products, and other goods.

The Environmental Cost and Benefit

The environmental impact of batteries begins long before they are discarded. Elements like lithium and nickel are mined globally — over half the world’s cobalt reserves are in Congo. The production process, including refining and shipping, adds to batteries’ carbon footprint. Manufacturing batteries themselves releases carbon emissions and pollution into the air.

“One person’s single battery is not necessarily a lot,” said Jennifer Sun, an environmental scientist at Harvard University. “But everyone uses many batteries.”

Recycling prevents the need to mine new materials for battery production and other goods.

“You continue to recycle and you don’t have to go back to the Earth to mine,” said Oladele Ogunseitan, a public health expert who studies electronic waste at the University of California, Irvine.

Safely recycling a battery does not erase the environmental cost of making it, but it gives the battery’s materials their best chance at a second life — and protects homes, waste facilities, and the environment from the hazards of improper disposal.