On Monday, March 18, 2013 10:33:49 AM UTC-4, Andy wrote:
Applied voltage was 13.8.

Surely that isn't the voltage across the (six) batteries during charge, that would be much too high.

Possibly useful info:

I use a LaCrosse charger for AA batteries, most of which are the low self discharge type, usually charge at 500 mA. The batteries will get warm at end of charge and voltage usually peaks around 1.5V just before cutoff. I don't think the voltage goes above 1.4V for more than ten minutes (but have not paid close attention). Most of the charge happens at 1.2 - 1.35 V/cell. This gives perfect results in a charger that has four batteries more or less exposed. Same cycle in a totally enclosed space might get pretty toasty.

If you are seeing more than 9V across the batteries at any time during charge, I'd really wonder about that.

T8