Answer: Batteries

If you dutifully recycle your old household batteries, you may wonder exactly where they end up at the end of the recycling road. If you were curious enough to dig into it (and we certainly were), you might be surprised to learn that a big chunk of the batteries you drop off at the local waste management company end up as corn fertilizer.

If that sounds a bit hard to swallow, let’s walk through the process of how a bucket full of batteries ends up sprinkled on soil used to grow corn. The batteries are taken to a recycling facility where they are sorted by type. Alkaline batteries, the most common type of household battery, are sent through a machine that pulverizes them in order to break them up into small pieces.

Those small pieces are then sent through a mechanical and chemical sorting process that separates the paper and steel exterior of the battery away from the elemental components in the battery like zinc, manganese, and potassium. Those three elements are then mixed into a micronutrient rich powder (or sometimes a liquid slurry) and applied to crop land to boost micronutrient levels in the soil and create more favorable growing conditions—thus completing a curious journey for the battery that took it from your flashlight to a field.