|Posted by Klein on October 22, 2012 at 10:35 PM|
(6 Oct 2012)
After my AA NiMH batteries overheated in my home-made charger, I thought to test them. I had 13 good batteries out of my pack of 16.
The test rig is shown in the photos. The rig is a spring for the load (~1.2 ohm), a travel clock (PowerPuff girls!) for the timer, and a voltmeter to monitor progress. This puts about an amp load on the battery (the spring gets hot). The clock stops at about 0.8 volt, and I stood by to remove the battery after the clock stopped. Good batteries ran about 2 hours, spot-on for their rating of 2000 mA-hr. Bad batteries drained in 5 to 15 minutes.