Hank: If you've heard that lithium-ion batteries don't go in the trash, here's why: They can accidentally cause literal dumpster fires.

Commonly used lithium-ion batteries leach toxic chemicals into the ground, so sending them to a landfill is bad. But on top of that, they are flammable. They can start fires when crushed, stabbed, heated, or aged. Over about 20 seconds, they will smoke and then spark, and then produce a jet flame up to 222 °C. This happens because punctures increase the pressure inside the battery and kicks off a chemical reaction. The added heat melts the film between positive and negative electrodes, causing a short-circuit. And if the battery isn't totally drained when you throw it out, its charge can fuel that fire.

So to avoid that fire and that danger, you can either recycle them with the manufacturer, or take them to hazardous waste collection points. There's a link in our pinned comment to help you find one.

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