Batteries thrown in household rubbish bins cause about 700 fires every year in dustcarts and waste-processing centres, local authorities say.
Lithium-ion batteries can explode if damaged or crushed. The Environmental Services Association says resulting fires cost fire services and waste operators some £158m a year.
Non-profit organisation Material Focus, which surveyed local authorities, runs an online search tool to help people find their nearest recycling point.
Found in small, rechargeable devices such as toothbrushes, toys, phones and laptops, lithium-ion batteries have become more powerful in recent years. Smaller, frequently used and cheaper devices – even some musical greeting cards – often have “hidden batteries”.
Ben Johnson, from the Environmental Services Association (ESA), told BBC News “more and more people were putting devices containing these batteries in with household rubbish” or mixing them with other recycling.
“That causes a real problem, because they have a tendency – when damaged – to explode or ignite,” he said.
“And when you put them in general rubbish or recycling, they’re likely to be crushed, compacted, smashed or they might get wet.
“That can cause them to short-circuit. And of course they’re then in the presence of other flammable material like plastic, paper and card and that can lead to quite big fires.”
The main type of rechargeable battery in portable consumer electronics, they consist of two electrodes divided by a separator that allows charged particles – lithium ions – to flow, through a solvent, from one to the other.
Recharging the battery pushes the ions back to where they started. If the battery is intact and contained, it is generally very safe.
But if the electrodes make direct contact with each other, it can cause all the charged particles to suddenly discharge in an explosion, which, as the chemicals inside the battery are flammable, can quickly cause a fire.