The overwhelming majority of AA and AAA alkaline batteries available to consumers are composed of manganese and zinc electrodes contained in a steel can. Electrons flow from the negative electrode, the anode, to the positive electrode, or cathode, producing a charge that we use to power our electronics. Both metals are surrounded by an electrolyte solution of potassium hydroxide, which allows the reaction to continue without building up charge on one end.
These batteries “die” when one electrode loses ions and becomes depleted, so the reaction cannot continue. Now that you are left with a dead battery, what should you do with it?
First and foremost, do not attempt to recharge it. Alkaline batteries are not designed to be recharged and the process can be quite dangerous without the proper equipment and knowledge. Because alkaline batteries are tightly sealed during production, gases formed during the recharging process normally cannot escape fast enough and can cause the cell to leak or rupture. So, as a general rule, if the battery is not explicitly marked as “rechargeable,” don’t recharge it.
Legal requirements for disposing of non-rechargeable batteries
The easiest thing to do with a dead battery is to simply dispose of it in the trash (in most parts of US). Since mercury has not been used in batteries since 1996, the United States does not consider alkaline batteries harmful. California is the exception to this, as the state’s Universal Waste Rule makes it illegal to throw out any type of battery.
The European Union has also instituted legislation to prevent batteries from ending up in landfills, such as the Batteries Directive. Rather than throwing out used batteries, the EU and California prefer to recycle them.
Why you should recycle batteries
Recycling batteries is favorable for both economic and environmental reasons. All batteries contain metals, in some cases very expensive metals, such as the indium hydroxide that replaced mercury in alkaline batteries (100 grams of this sells for about $300). However, even if a battery contains relatively inexpensive metals, it would still be a colossal waste of resources to permanently dispose of dead batteries.
Thanks to efficient recycling processes like the one developed by Retriev Technologies, battery recycling is an economical and prudent option; companies like Energizer have already started producing alkaline batteries containing some recycled material.
In terms of environmental concerns, batteries almost always contain some kind of corrosive material or heavy metal. When these substances escape the battery they can leach into the soil and pollute the area around the landfill as well as groundwater.
It is true that alkaline batteries no longer contain mercury, but the potassium hydroxide electrolyte they contain is not as benign as the potassium found in bananas. It is a strong and highly caustic base that can cause irritation and burns when in contact with skin, and is not a chemical we want in our environment.
How to recycle non-rechargeable batteries
If you are convinced that recycling batteries is the best option, keep in mind that you cannot simply dump batteries in the same recycling bin as paper, glass, and plastic as most recycling facilities are not equipped to recycle objects like electronics and light bulbs. However, there are easily accessible programs that collect batteries for recycling.
Many city halls and universities throughout the country host expansive recycling efforts, and usually collect batteries as a part of that. If access to these places is not convenient for you or they do not offer battery recycling, Earth911 offers a handy tool to locate places where you can drop off your dead batteries.
If you’re unable to physically bring your batteries in for recycling, there are mail-in options that allow you to ship your batteries to a recycling facility. Waste management companies, like the appropriately named Waste Management, run such programs, and can often send battery recycling kits at your convenience.
Finally, services like The Big Green Box allow you to purchase a box to collect batteries and electronics, and then ship it back to them for recycling.
Keep in mind that some battery collection locations may only collect specific types of batteries – many of them only accept rechargeable batteries. Make sure that your location accepts alkaline batteries before you ship them or bring them in.
Storing your dead batteries for recycling
Once your battery has died and you have removed it, cover the positive end (or both ends) with a piece of tape to insulate it and place the battery in a plastic bag or container designated for recycling.
It is convenient to wait until you have collected a dozen or so batteries before bringing them in for recycling to save you from multiple trips, but keep in mind that old, used batteries might leak.
If you encounter a battery with a white foamy crust around the rim, avoid touching the battery with your bare hands and place the battery in a separate plastic baggie or container. It can still be recycled along with the other batteries.