You're bound to feel good when you learn how to recycle batteries.

We use batteries to power any number of household items: remote controls, cameras, flashlights and portable power tools, among others. According to the U.S. Environmental Protection Agency, each year Americans buy almost 3 billion dry-cell batteries to power these common household items. The average American discards eight batteries each year.

And as we do with other items that we no longer need, it's tempting to just throw used batteries in the trash, but that would be a mistake.

Inside a battery, heavy metals react with chemical electrolyte to generate power. The metals found in batteries include mercury, lead, cadmium and nickel.

Environmental hazards of batteries

If batteries are not recycled, these metals can pollute the environment.

Depending on how batteries are discarded, the metals can be released into the air or remain behind in the ash created by incineration.

Batteries that are disposed of in landfills can leach into the soil, contaminating groundwater supplies. This is especially true of automotive batteries, which contain lead and acid.

Instead consumers are encouraged to separate batteries from the regular household trash and find a proper place to dispose of the batteries.

Rechargeable batteries have reduced the amount of batteries that need to be recycled. But even so, the majority of batteries are single-use.

Batteries can be divided into two broad categories: dry-cell and wet-cell batteries.

The dry-cell type is used in most consumer electronics, and includes alkaline and carbon zinc batteries (namely 9-volt, D, C, AA and AAA) and lithium batteries (comprised of 9-volt, C, AA, button and rechargeable versions).

Wet-cell batteries are typically found in cars, boats and motorcycles.

Both types of batteries can be recycled.

A special note about alkaline batteries: These batteries, which are used in some of the most common consumer electronic products, are considered non-hazardous and many municipalities say residents can safely dispose of them with the rest of the household trash. However, these batteries do contain items that if recycled, could be reused.

How to recycle car batteries

The wet-cell batteries we use in our cars are the easiest to recycle, so let’s start there.

Most retailers of car batteries are also authorized collection and recycling centers for them. For example, chains such as AutoZone and Advance Auto Parts recycle used car batteries for free.

How to recycle dry-cell batteries

There are a variety of places where dry-cell batteries can be recycled, including municipal sites and for-profit entities such as retailers and sanitation companies.

Some cities have established permanent collection sites for hazardous household materials such as batteries (and indeed some cities have outlawed the disposal of batteries and other toxic materials in municipal dumps, though federal law permits it). Other cities hold special collection days one or more times a year.

Dry-cell batteriesConsumer electronic chains such as Best Buy, Circuit City and Office Depot also typically have recycling kiosks inside their stores or outside the front entrance. Recycling batteries at these locations is usually free and consumers do not need to have purchased batteries at a particular retailer to take advantage of its program.

Button batteries are often found in watches and hearing aids. Retailers of these items often recycle the batteries for customers for free.

Consumers can receive information about recycling centers from their municipalities, or they can consult Web sites such as http://earth911.com/, which is endorsed by the EPA, to find municipal and other collection sites. Visitors to the site plug in their zip codes and the types of batteries they want to recycle.

Another site that provides the same service is http://www.call2recycle.org/. The site is run by The Rechargeable Battery Recycling Corp., which is a non-profit organization that promotes sustainability.

Companies have sprung up to fill the need for recycling batteries.

For example, Battery Solutions will accept batteries by mail or will arrange pickups for customers. The Big Green Box is another firm that recycles batteries from anywhere. 

The company mails customers a cardboard box for safe disposal of up to 40 pounds of alkaline, lithium, mercury, zinc and other types of batteries. Consumers then mail the box back to the company.

This can be a solution for home offices and small businesses.

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