Battery Buying Guide

Getting started

AA batteries are the most widely sold battery type, used in digital cameras, flashlights, radios, remote controls, toys, and much more.

To find out whether you really need to buy expensive brand-name batteries to keep your gadgets up and running, we tested both alkaline and lithium batteries.

How we tested

To measure how long AA batteries lasted, testers loaded them into digital cameras, a typically high-drain device, and flashlights, a low-drain device. For cameras, the test mimicked everyday use by zooming, flashing, shooting, and resting until the batteries died.

The longest-lasting battery took 682 shots before dying, while the quickest to die took just 52.

For flashlights, the test included turning on a flashlight for 4 minutes every hour for 8 hours, and then letting the flashlight sit for 16 hours. Testers repeated this routine until the batteries died. The best batteries in our tough test could last 7.5 hours, while others made it to only about 5.2 hours.

Rechargeable batteries

Rechargeable batteries are a greener choice than any of the tested types. In past tests, precharged rechargeables from the major manufacturers provided about 300 shots out of the box and about 400 shots on their subsequent charges.

For information about tossing or recycling batteries, go to www.call2recycle.org or earth911.com.

Bottom line

Lithium batteries took more photos than alkaline, which have a shorter life but cost less. Use lithium batteries in high-drain devices such as cameras, and alkalines in low-drain devices such as flashlights and remote controls. When it came to low-drain devices, some alkaline batteries performed almost as well as lithium. For toys that are used a lot, such as game controllers, consider high-capacity rechargeable batteries. In past tests, we've found that rechargeables of 2,350 milliamp-hours or more are best for often-used toys such as these.

And remember, most alkaline batteries have a shelf life of about seven years, though some makers claim up to 10 years.