Research estimates that only 5% of batteries are recycled. Recycling batteries allows the important non-renewable resources in batteries such as cadmium, zinc, lithium, mercury and lead to be recovered and reused.
Those same chemicals that are so useful when reused can be dangerous in a landfill. When left out in the elements, these batteries can become toxic and leak chemicals into the ground where it can pollute the groundwater. Battery corrosion can also cause soil pollution and will harm any animals or birds that come in contact with the battery.
Lithium metal batteries can also cause explosions or fires if inappropriately stored or disposed of because of the tenuous nature of the interior chemicals.