I've been using the batteries regularly and generally don't let them go completely dead. I have 4 of them, and first noticed the charging problem with 2 of the batteries. However, when I tried to charge them again today, I got the flashing light on my charger with all 4 batteries -- either trying to charge them all together or just 2 at a time. I also tried charging them in another charger and the same thing happened, with the charge indicator light flashing on and off.