Some of these toxic heavy metals include nickel cadmium, alkaline, mercury, nickel metal hydride and lead acid, which can threaten our environment if not properly discarded. There are recycling programs in place for all of these materials - so batteries should be recycled when ever possible and never thrown in the trash.
In 1996, the Battery Act was signed into law to address two fundamental issues according to the U.S. EPA:
- to phase out the use of mercury in batteries and
- provide collection methods and recycling/proper disposal of batteries.
Batteries that end up in landfills and incinerators eventually leak into the environment and end up in the food chain, causing serious health risks to humans and animals.
Not all batteries are the same and they require specific instructions to ensure each type of battery is properly discarded or recycled. All batteries can be categorized as either primary (single-use) batteries or secondary (rechargeable) batteries. This guide breaks down the different types of batteries based on those two categories.
Each year, Americans throw out almost 180,000 tons of batteries. About 14,000 of those tons are rechargeable batteries; the rest are single-use. Fortunately, a lot of rechargeable batteries can be used to power the same products in which we typically use single-use batteries. If we start replacing those one-use batteries with rechargeable, we are not only saving money, but ensuring that less batteries end up in the landfills as well!
Each battery has a different chemical makeup, and therefore, there are different ways of properly disposing of them. The guide below should help you determine what type of battery you are dealing with, how to dispose of it, and give you a little bit of background on the battery, too.
Primary, One-use Batteries
This type of battery is one of the better choices for consumers. The batteries last longer, perform better at high and low temperatures and have a longer storage life. Alkaline batteries can be stored at room temperature for two years and retain 90 percent of their original capacities. They used to be more expensive than carbon-zinc and zinc-chloride batteries, but because of the increased manufacturing, these batteries are now comparably priced and outperform those other batteries.
According to the EPA, potassium hydroxide, a strong alkali, is contained within the cells of alkaline batteries. The potassium hydroxide can leak out of the battery cell if alkaline batteries are damaged or mishandled, causing severe chemical burns if the substance comes into contact with your skin or eyes.
- Standard Alkaline – typically used in low to moderate-drain devices like scanners and remote controls.
- Premium Alkaline – typically used in high drain devices such as digital cameras and CD players.
When disposing of household alkaline batteries, it is best to check with your local and State Recycling or Household Hazardous Waste Coordinators concerning the specifics of your program.
Carbon-Zinc and Zinc-Chloride Batteries - Carbon zincs have been almost entirely replaced by alkaline batteries. They don’t do well in extreme temperatures; excessive heat drives out the moisture from the chemical mix in the cell and drastically low temperatures decrease the life of the battery. These batteries are most commonly used in flashlights and products with intermittent use. They are inexpensive and therefore a popular choice among manufacturers that sell products with batteries included. Many reclamation companies will process these batteries, so check with your local recycling services before you dispose of these with the rest of your waste.
This type of battery is most often found as a button cell or cylindrical. Lithium manganese batteries have a much better storage life than most batteries and can be stored for several years. Temperatures have little effect on the operating capabilities of these batteries; they also work very well in low temperatures, so they are used a lot in outdoor devices, such as wireless weather devices.
The button cell form can be found in watches and pacemakers and most products with a slim profile. Products with other varieties of lithium manganese batteries include heavy-use flashlights, handheld video games, shavers and electric toothbrushes. One of the recycling processes currently available for lithium-containing batteries involves recovering the lithium in the battery and selling it back to battery manufacturers.
Silver Oxide Batteries
Silver oxide (silver-zinc) batteries are round and come in two types: sodium hydroxide and potassium hydroxide. Sodium hydroxides last about two to three years and are recommended for analog digital watches without backlights, while potassium hydroxides are a better option for LCD watches with backlights. Silver is expensive, but these batteries are available in small sizes where the amount of silver used is so small it does not affect the price or in larger sizes where the superior performance of the battery outweighs the cost. In addition to watches, silver oxide batteries are also found in hearing aids, calculators and pagers. These batteries contain mercury, so they are hazardous and should not be sent to a landfill. The recycling/disposal process of these batteries involves shredding the batteries, neutralizing the electrolytes and recovering the heavy metals.
Secondary, Rechargeable Batteries
Nickel-Cadmium Batteries (NiCd)
The nickel cadmium battery was the first rechargeable battery that was reasonably priced and available in the standard cylindrical sizes (AA, AAA, etc.). These batteries come in two types: vented cells and hermetically sealed cells. Vented cells must be positioned so they can vent properly and also require water for maintenance. They are commonly used in commercial and military applications. Hermetically sealed batteries, however, do not require any maintenance and they do not need to be specially positioned.
These batteries are used in low- to moderate-discharge devices such as scanners and portable radios. Since these batteries contain cadmium, a toxic heavy metal, they require special disposal. In the United States, there is a fee built into the price for nickel cadmium batteries which includes proper disposal of the batteries at the end of their lifetimes. All NiCd batteries are identified by the EPA as hazardous waste and must be recycled. The recycling process recovers cadmium and iron-nickel for steel production.
Nickel-Metal Hydride Batteries (NiMH)
The main difference between this battery and the NiCd battery is the metal hydride used instead of the cadmium. Nickel-metal hydride batteries are also available in the standard cylindrical sizes. These batteries also have two to three times the capacity of a nickel cadmium, and the memory effect is not as significant. Memory effect is when a battery’s maximum energy capacity gradually decreases as a result of being recharged before the battery has completely discharged.
Nickel-metal hydride batteries are commonly used in high-discharge devices like portable power tools, digital cameras and laptops. They are considered non-hazardous waste, but do contain elements that can be recycled. The individual materials of the batteries are mechanically separated, and a high nickel content is produced and used in the manufacture of stainless steel.
and Lithium-Ion Polymer Batteries
These batteries only come in rectangular or cylindrical shapes. There is no issue of a memory effect with these batteries, meaning they can be recharged before they are completely discharged without affecting the energy capacity. They are smaller, lighter and provide more energy than nickel cadmium or nickel-metal hydride batteries.
Lithium batteries are most often used in cell phones and mobile computing devices. They should not be stored in hot cars over the summer because when they reach high temperatures, they can easily ignite or explode. They can also explode if damaged, so do not mess with the casing of the batteries. It is highly advised that when storing these batteries for recycling you tape the terminals. These batteries are recyclable, and the metal content of these batteries can be recovered in the recycling process.
Acid Batteries (Automotive & Sealed Lead-Based)
Lead acid batteries are the oldest type of rechargeable battery. They should never be fully discharged because this will completely kill the battery. Hopefully, a battery will be created that can replace the lead acid battery because there are environmental concerns about improper disposal of these batteries, which are most frequently used in automobiles.
Sealed lead batteries should be recycled, as they contain hazardous materials and elements that can be reused. Over 97 percent of all battery lead between 1997 and 2001 was recycled, however, making lead acid battery recycling one of the most successful recycling programs in the world.
Vital Stats from U.S. EPA:
- Americans purchase nearly 3 billion dry-cell batteries every year to power radios, toys, cellular phones, watches, laptop computers, and portable power tools.
- Nearly 99 million wet-cell lead-acid car batteries are manufactured each year.
- A typical lead-acid battery contains 60 to 80 percent recycled lead and plastic.
- On average, each person in the United States discards eight dry-cell batteries per year.
Help the Environment - Batteries
by Earth 911 Staff on April 2nd, 2007
Prevention of Household Battery Waste
To reduce waste, start with prevention. Starting with prevention creates less or no leftover waste to become potentially hazardous waste. The following are steps to take to prevent household battery waste.
- Check to see if you already have the batteries on hand before buying more
- When suited to the task buy hand operated items that function without batteries
- Look for the batteries that have less mercury and heavy metals
- Consider rechargeable batteries for some needs, but remember that they also contain heavy metals such as nickel-cadmium.
Rechargeable batteries result in a longer life span and use fewer batteries. However rechargeable batteries still contain heavy metals such as nickel-cadmium. When disposing of rechargeable batteries, recycle if possible.
The use of rechargeable nickel-cadmium batteries can reduce the number of batteries entering the waste stream, but may increase the amount of heavy metals entering the waste stream unless they are more effectively recycled. As of 1992, the percentage of cadmium in nickel-cadmium batteries was higher than the percentage of mercury in alkaline batteries, so substitution might only replace one heavy metal for another, and rechargeable batteries do use energy resources in recharging.
Rechargeable alkaline batteries are available along with rechargers.
Additional Tips for Longest Life Use of Batteries
- Turn off any battery-operated appliances when not in use
- Remove batteries from appliances if they are not going to be used for a long time.
- Do not recharge a battery unless it is specifically marked rechargeable. Attempting to recharge a non-rechargeable battery can cause it to leak or rupture
- Do not dispose of batteries in a fire it may cause them to explode.
Usefull Link: How Batteries Work” by Energizer