When to use rechargeable batteries and how to recycle them

PHILADELPHIA (WPVI) -- Batteries power all kinds of things from our TV remote to flashlights to toys. But before you buy a fresh batch, Consumer Reports has dug into why and when to use rechargeable batteries.

Not only can they save you money but they are better for the planet.

Meghan Patterson and her family have been using rechargeable batteries for about eight years.

"I worry a lot about our environmental impact when it comes to things like batteries," she said.

Both rechargeable and single-use batteries contain toxic chemicals and heavy metals that can pollute the environment. They both also require water and energy in the manufacturing process and release greenhouse gases into the atmosphere.

But a 2016 study in The International Journal of Life Cycle Assessment says that rechargeable batteries are more sustainable than disposables after you've used them at least 50 times, something that shouldn't be a problem for many families.

Consumer Reports says toys and your wireless computer mouse are great uses of rechargeables because they usually draw a lot of power over a short period of time.

"You know, you buy them once and you can recharge them around a thousand or so times," said Shanika Whitehurst of Consumer Reports' Product Sustainability.

Just make sure you also buy a charger that can accommodate all the different sizes you'll be using, she said.

As for single-use batteries, CR says they hold a charge longer and are best for things like smoke detectors and emergency tools like flashlights.

"That's what they're designed to have a slow discharge for those types of items where you kind of need them on the ready," said Whitehurst.

All batteries, even the rechargeable ones, eventually die. And if you've ever left batteries in an old device and found that they leaked, you can just imagine what happens to them in a landfill. To help keep those toxic chemicals out of the environment, recycle them.