THE SAME, BUT DIFFERENT
Our experience has shown that batteries — even seemingly identical ones — aren’t necessarily the same.
In testing lights with rechargeable lithium-ions (like the one shown at right), we use the supplied batteries and charged them per instructions. For those using disposables, we use new, major-brand batteries just out of the box, purchased at the same place and time.
With Li-ions (which are more difficult to test than alkalines), we’ve found that burn times can vary noticeably, likely related to a battery’s use and charging history. And in this test, when the output of a AA light came out lower than expected, we tried another set of batteries — from the same package as the first. The result was nearly 40 percent more light output.
Bottom line: Use highquality batteries that meet the light manufacturer’s requirements, and replace them at the first sign of trouble.