When to choose rechargeable batteries over disposable

Whether it's for a camera, torch, clock or smoke alarm – battery needs change depending on the device.

This article was written by Chris Heinonen of Wirecutter (New York Times group) and republished by CHOICE. It was originally published on the Wirecutter website. You can read it here in its original version. Photo lead: Sarah Kobos © 2019 The New York Times.

Last year I went to change the batteries on my label maker only to find the back encrusted with whitish discharge from leaky alkaline batteries. I have a big stash of rechargeable batteries – would that have saved my label maker from corrosion?

Probably. I talked to our staff writer Sarah Witman, who recently updated Wirecutter's guide to rechargeable-battery chargers. Sarah told me that rechargeables are made of generally more corrosion-proof materials than disposables are. The latest ones are made with low-self-discharge nickel-metal hydride (LSD NiMH) and they tend not to leak the way that alkaline batteries do. They can still corrode but they don't tend to do it as often.

And you don't lose much by switching. Our favourite AA rechargeable batteries, the Energizer Recharge Universal, have two or more times the capacity of a cheapie disposable. And they have excellent shelf life – maybe not quite as long as disposables, but in our testing we found that they can last for years when stored in a cool, dry place. Sarah said, "Rechargeable batteries are almost always the better choice."

If you're trying to decide when to use alkaline over rechargeable, Sarah said, "Things with a low power draw – like some wall clocks, cameras, or flashlights – work better with alkalines because they release power consistently right up until they die, whereas a rechargeable battery's voltage will get gradually lower and lower over time and cause problems. 

"Also, most smoke-alarm brands tell you not to use rechargeable batteries. You should always check the manufacturer's instructions to find out what kind of batteries you should be using, and how often to swap them out."

See CHOICE's disposable battery reviews and rechargeable battery reviews to find out which brands we recommend.

When you find a device with corroded batteries, here's Sarah's advice: "Remove the batteries from your device and recycle them. Then you should clean out the battery compartment with a tablespoon of boric acid diluted in a gallon (3.8L) of water, or else a solution of equal parts vinegar (or lemon juice) and water."

© 2019 Wirecutter thewirecutter.com – Distributed by The New York Times Licensing Group