What is the best way to dispose of used alkaline batteries? I have heard they should not go into the landfill, but I have also heard that battery recycling programs are not effective or efficient. I would love to know what is the most ecologically sensitive way to dispose of these batteries!
Asked by Kristi Holmes Espineira, '89, Highlands Ranch, Colo.
So, you've got your battery-recycling bin set up. Now what happens?
According to Dave Nelson of Battery Solutions (the recycling company Stanford uses for its batteries) nearly every part of the battery is recycled. The steel casing is stripped off and used for low-grade steel and rebar; the paper and plastic is removed and may be incorporated into road surfacing; and the zinc and alkaline manganese core is chemically processed and purified. Some of the manganese is even used for fertilizer.
So, even though battery recycling is often not profitable at current commodity prices, the batteries are squeezed for every material they can possibly provide. And, as Nelson suggests, this is better than sitting in a landfill, as it saves new materials from being mined. It can also save energy: recycling steel is 70 percent more energy efficient than mining and processing new ore.
But what about you? Is there anything else you can do, now that you're recycling batteries? And if you aren't recycling batteries, is there any way to reduce your battery waste? One step might be to use a different kind of battery. As I mentioned in the Essential Answer, there are many types of batteries.
1: Rechargeable batteries can be used in place of the single-use type. Rechargeable nickel-cadmium batteries last many times longer than single-use alkaline batteries, and some are good for 1,000 charge cycles. Rechargeable nickel metal hydride batteries will last for about 500 charges, and rechargeable alkaline batteries last for a few dozen charges.
Some rechargeable batteries are not useful for replacing alkaline batteries in household electronics, as they have specialized functions. But they are still worth knowing about, and I will describe them briefly here.
2: Lead-acid batteries are large and used in motor vehicles such as cars and boats. These batteries contain both lead and sulfuric acid, both of which could be quite damaging to groundwater. However, the recycling program for car batteries in the United States is one of the most successful recycling programs in the world: 97 percent of all spent car batteries are collected for recycling. The lead and plastic coverings are reprocessed for use in new batteries, and the acid is chemically neutralized and treated as wastewater.
3: Lithium-ion batteries receive a lot of attention, as these are the batteries found in laptops, cell phones and other portable electronics. These are not toxic per se, but are prone to exploding or catching fire when physically damaged, as could happen in a landfill. So, they should still be recycled instead of trashed. Their lithium innards are recoverable and reusable.
Even though rechargeable batteries can save a lot of single-use batteries, the inevitable run-down eventually occurs, and you're left with a little hunk of metal that was once useful but is now nothing more than scrap.
You may recall me saying that alkaline batteries are reasonably safe to throw away. This is not true for most rechargeable batteries, as you may have guessed from the descriptions of the batteries above. Nickel-cadmium batteries contain cadmium (it's right there in the name!), a toxic heavy metal. Even the nickel is considered somewhat toxic. Of course, since batteries are so small, it's tempting to just throw them in the garbage. After all, how much difference could one little battery make?
Unfortunately, batteries do make a difference, especially since we use so many of them. It is estimated that a good 88 percent of mercury in landfills comes from discarded batteries, despite the fact that batteries make up less than 0.1 percent of municipal solid waste by mass. The toxic, heavy metals (mostly lead, cadmium and mercury) can dissolve over time and seep into groundwater, poisoning wells and river systems. This is especially problematic when the waste is incinerated, as the heavy metals can vaporize and rise into the atmosphere, causing severe health problems for local people.
So, if you use rechargeable batteries, you need to recycle them, and in the case of nickel-cadmium batteries, you are required to by law. They are toxic when exposed to the environment and contain more valuable metals than alkaline batteries do. If you're already recycling alkaline batteries, recycling rechargeable batteries should not be a big deal, as many companies that take alkaline will also take nickel-cadmium and nickel metal hydride batteries. In addition, many retailers will take and recycle rechargeable batteries for free. Locations for battery drop-off can be found at the Rechargeable Battery Recycling Corporation website. Recycling aside, rechargeable alkaline batteries can save some of your waste. And that's something to get charged up about.
Rachael Monosson, '11, is an earth systems major.
