Originally Posted by
Mondoman
I had the same problem with a pair of Costco house-brand Kirkland AAA alkaline batteries yesterday on my Mars 3.0. The light was nice and bright at first, indicating proper voltage in both batteries, but was very dim by the end of my ride. Voltmeter showed one of the batteries reading only 0.6V. It would be nice to know about short-life defective batteries in advance -- does anyone have suggestions for a load tester or similar that would help sort the wheat from the chaff in a 20-battery bulk package?
My gut feeling is that if you checked the voltage of both batteries with a volt meter before using them, the bad one would have been too low to start with. If it started at 1.2 V and the good one was close to 1.5 V, the light would have been pretty bright for a while. I've seen this happen with rechargeables that are starting to go bad.