Lithium-ion batteries are potent devices, which is why they’re so useful. That’s also why they can be a problem.
“The amount of energy you can pack in such a small object is great, but that energy can cause fires,” said state Deputy Fire Marshal Tony Booth.
In particular, they can cause fires at transfer stations — in dumpsters or compactors or garbage trucks — if people toss rechargeable batteries in the trash and they get crushed or broken.
Several organizations gathered Wednesday at the town of Moultonboro’s transfer station to dramatize the problem, showing three scenarios in which discarded batteries caused a fire.
That’s why the state Legislature last year made it against the law to throw rechargeable Lithium-ion batteries in the trash, recycling or incinerator. Facilities must offer a special place to put them.
Unfortunately, people still do throw them out, either because they don’t realize a battery is rechargeable — it’s perfectly fine to throw away old-fashioned alkaline batteries — or because it’s inside a device like a vape pen and they don’t realize it’s there.
“Anything that’s rechargeable is a problem,” said Booth. That’s includes e-bikes, scooters with batteries and other e-mobility devices.
“People have an old bike, they bring it to the transfer station,” said Booth.
The problem is that rechargeable batteries have a thin plastic separator which keeps the positive and negative layers apart, while letting ions move through a flammable liquid electrolyte. Shifting those ions back and forth is what makes the battery rechargeable.
If the separator gets damaged, the current can heat up the electrolyte and cause a “thermal runaway” in which heat leads to more heat which leads to flame.
This is a real concern in electric vehicles after road accidents because rechargeable battery fires can’t be extinguished by suffocating them, as can be done with gasoline fires. Basically you have to remove enough heat to stop the runaway, which can take huge amounts of water.
That’s not the problem in a transfer station fire, however, because those batteries are small. The problem is that a battery fire can ignite other material in the trash, which can spread the flames and release toxic gases.
An EPA study released in 2021 said Lithium-ion batteries caused over 245 fires at 64 landfills across the United States in seven years. By 2024, a report by the National Waste and Recycling Association estimated more than 5,000 fires occur every year at waste management facilities nationwide, many likely caused by rechargeable batteries although the cause is often not pinned down.
In New Hampshire, Lebanon, Keene and the town of Lee have reported fires at their solid waste facilities, causing thousands of dollars in damage.
