More than 700 potentially poisonous dead or used vehicle batteries are headed for recycling, thanks to participants in AAA Carolinas’ seventh annual Great Battery Roundup.

In conjunction with Earth Day (April 22), AAA Carolinas-affiliated facilities throughout North Carolina and South Carolina provided free battery checks and paid $1 for each battery brought in between April 16-21.

Repair facilities that accept dead batteries often charge a fee of up to $5, which is usually refunded with a new battery purchase.

More than 101 million lead-acid batteries are sold each year in the United States. A large number of batteries are illegally disposed of in dumps and water sources or simply sit in the corner of someone’s garage where they can contaminate soil and groundwater, explode in a fire or become a source of lead poisoning to humans and animals. The longer a battery sits, the more likely it is to leak dangerous acids.