We are a country that loves our electronic gadgets, but when it comes to keeping them charged, it gets complicated.

The Sierra Club estimates about 5 billion batteries are purchased in the United States every year, but less than 10% get recycled.

Whether it's a standard alkaline AA battery in your smoke detector, a rechargeable nickel-metal hydride in your cellphone or a wet-cell car battery, most of them contain toxic chemicals like cadmium, lead, zinc, manganese, nickel, silver, mercury and lithium.

That kind of chemical concoction means batteries need to be disposed of or recycled safely and knowledgeably. When it comes to knowing what can go in the trash and what needs a special trip to a recycling center, it's hard to get a straight answer because recycling and disposal laws differ state by state.

Though it seems like a relatively minor act, tossing a battery in your trash can lead to some seriously harmful effects on the environment.

"Whether it's your standard alkaline AA battery, a rechargeable cell phone battery or the battery from your car, you should treat it with care by using safe storage and disposal methods," says James Dickerson, Consumer Reports' chief scientific officer.

If a battery winds up in an unlined landfill, it may leach its metals into the soil, contaminating groundwater supply. And if it burns up in an incinerator, that's just more toxic junk drifting up into the air we breathe.

If that's not scary enough, consider that if they're not disposed of properly, they can short circuit, overheat and burst into flames. Depending on where you live, it may even be illegal to dispose of a battery.

Battery life

a smushed battery split open on ground Check your state laws before tossing that battery in the trash. (Photo: Aaron Hall [CC by SA 2.0]/Flickr)

Over the years, batteries have been made out of some seriously toxic stuff. Thankfully, mercury is now out of the picture. Congress passed the Battery Act in 1996, which called for the phasing out of mercury in batteries, and with it, country-wide, cost-effective solutions to recycling and proper disposal.

This led to the creation of industry-backed recycling programs like the Call2Recycle program, which is still thriving today. It's thanks to them that there are more than 16,000 public drop-off sites across the nation these days.

When it comes to choosing the right battery, it all depends on how much you'll use it. The carbon footprint of manufacturing a single battery is huge. According to a study from MIT's Department of Materials Science and Engineering, 88% of a single-use battery's environmental output comes from its sourcing and processing.

The study states, "Of the phases … directly within control of the battery manufacturing industry, the manufacturing facility has the largest impact [through electricity use]." Creating a battery takes a lot of energy, and unfortunately, the majority of U.S. battery production uses fossil fuels to get its power.

Using the MIT study data, a paper published in the Journal of Industrial Ecology estimated that "it takes more than 100 times the energy to manufacture an alkaline battery than is available during its use phase." It's especially frustrating when you consider that battery technology is slow to advance, thanks to the combination of commercializing battery design and the chemical processes involved.

On top of that, the chemical compounds found in our batteries don't exactly grow on trees. They're full of manganese dioxide, graphite, zinc, and potassium hydroxide — all of which come from mining and refining.

The hidden costs of batteries

a man mines sulfur in Indonesia Men who work in this sulfur mine in Indonesia deal with brutal heat, toxic fumes and heavy loads in exchange for very little money. (Photo: Jean-Marie Hullot [CC by SA 2.0]/Wikimedia Commons)

A recent deep investigative dive into the hidden costs of Amazon's "store-brand" batteries revealed a host of problems behind a basic battery's life cycle. While big battery players like China, Japan and Korea are still in the game, Indonesia is an up-and-comer, thanks to its rich deposits of natural resources and lax environmental regulations.

Manganese, a key ingredient in alkaline batteries, is linked to human rights abuses, child labor and poor occupational health, while lithium mining puts workers' health and safety at risk. Figuring out if the metals in your battery were mined responsibly is also tricky because there's little to no traceability along the supply chain.

Before purchasing, first figure out how many times you'll need to charge a certain item. High-consumption items like flashlights, cameras and electronic toys are excellent candidates for rechargeable batteries — just consider that the International Journal of Life Cycle Assessment states you'll need to recharge them at least 150 times to offset their environmental impact.

Of course, none of the products that go into a battery are infinite resources. A more sustainable, less environmentally destructive source of power is needed; the crucial shift to truly renewable energy will be impossible without it.

Think sustainably, and assess all of your options before tossing that next battery pack in your shopping cart. Though they may seem innocuous lying dormant in your TV remote, a lot lurks beneath the surface of your everyday battery.

Dr. David Santillo, a senior scientist at Greenpeace Research Laboratories, told The Guardian: "We have to get smarter at recovering and reusing the vast quantities that we have already extracted from the earth, rather than relying on continued pursuit of new reserves of ever poorer quality and at substantial environmental cost."

Lindsey Reynolds ( @https://twitter.com/LindseyKateR ) takes an epicurean and academic approach to foodways, but she also writes about so many other things, including art, psychology and how to live an environmentally responsible life.

What's wrong with batteries?
This basic household item is full of hidden costs — from the environmental impact of mining to figuring out the safest way to dispose of them.