When to Use Rechargeable Batteries

·4 min read

They can save you money and help save the planet

By Rena Behar

If you’re trying to find ways to move away from single-use items for the sake of the planet, don’t overlook the humble AA (or AAA, or C, or D) battery.

Rechargeable batteries can cost more than twice as much as single-use batteries, but if you use them properly they’ll save you money in the long run because you can recharge them hundreds of times. Even so, they’re not always the greenest choice. According to a 2016 comparative life cycle assessment published in the International Journal of Life Cycle Assessment, rechargeable batteries are more sustainable than disposables only after you’ve used them at least 50 times.

In terms of manufacturing, both rechargeable and disposable batteries take a toll on the planet. “They both contain toxic chemicals and heavy metals that can pollute the environment,” says Shanika Whitehurst, associate director of sustainability at Consumer Reports. The manufacturing process also requires water and energy and releases greenhouse gases into the atmosphere. “But the extended lifespan of rechargeable batteries may offset the toll that making them has on the environment,” Whitehurst says, adding that some rechargeable batteries are now being produced using recycled materials, which further reduces their environmental impact.

The Right Battery for the Job

The most important thing to consider when choosing between disposable and rechargeable batteries is how you’re going to use them.

Rechargeable batteries are best suited for something that draws a large amount of power over a short time. “You get the economic and environmental benefits of rechargeables a lot faster in high-consumption devices, like the remote control for your kid’s toy car that eats up AA or AAA batteries,” Whitehurst says. While children’s toys tend to be some of the biggest battery hogs, the same applies to devices like wireless computer mice.

Single-use disposable batteries, on the other hand, are better for products that have a low energy pull over a prolonged period of time and are replaced infrequently, such as smoke detectors or your TV’s remote control. Single-use batteries are also better for any emergency supplies you may be keeping on hand, like flashlights. “Regular batteries are designed to hold their charge for extended periods so that they’re ready when you need them to be ready,” Whitehurst says.

When shopping for rechargeable batteries, there are a couple of key things to remember. First, rechargeables have a shelf life of about 5 years and can be recharged roughly 500–1,000 times, depending on brand and usage. That means you’ll probably need to buy fewer of them than you do when purchasing single-use batteries. Second, make sure you buy a charger that can accommodate all of the various sizes you’ll be using.

Keeping Batteries Out of Landfills

Eventually, every battery, whether single-use or rechargeable, will reach the end of its useful life. When it does, it’s essential that you dispose of it properly. In a landfill, batteries can leak, which means that the metals and other toxic components in them can be absorbed into the soil and contaminate the water supply. (If you’ve ever forgotten about the batteries in an old device and opened it up to discover an unpleasant leakage, you can imagine what happens when countless millions of them are put in the ground.)

Disposing of batteries at dedicated drop-off points (see Call2Recycle and Earth911 to find them) helps keep batteries out of landfills and their toxic components out of the environment. And when you recycle rechargeables, you’ll even be reducing the need to mine the metals required to make them. According to Lucia Rigamonti, PhD, an associate professor in the Department of Civil and Environmental Engineering at Italy’s Polytechnic University of Milan, some NiMH rechargeable batteries today are made with 15 to 20 percent recycled material.



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