3

So, what I should do is:

  1. Drain the battery, say 50%.
  2. Charge with the flashlight and check the voltage.
  3. Drain the battery, say 50%.
  4. Charge with a charger and check the voltage.

I had thought there were 2 factors involved in charging a battery:

  1. The current voltage level.
  2. And the amount of charging current.

My thoughts(as a novice) were when the amount of charging current drops to a preset low value for a given voltage, the battery would be deemed fully charged.

As appears to be the case with my Opus c3100 charger, I see a charge rate of 400mA or 500mA and this gradually drops to about 20mA before the battery is shown fully charged. I do also see a voltage of 1.47 VDC for AAA and such, where the rechargeable battery rating is 1.2 VDC.

I did not expect a “good” charging circuit to stop charging based on voltage alone.