Gentlemen, many thanks for all the feedback.
To respond to Dave's questions first: the charger
I have been using is an MRC Super Brain 989, and the recorder is an Eagletree Micropower E-logger V2; both are off-the-shelf items and not calibrated. I know there can be some discrepancy between the two, but surely not enough to explain the numbers? I cannot check the temperature of the battery
. That will be affected by another variable - charge and discharge current, will it not?
As Dave and Doug have pointed out, I made a very, very rough, simple, conservative calculation of mAh looking at the chart. I did not try to be mathematically precise. it was a number for me to explain my question of whether the apparent charge and discharge efficiencies made sense and could they be explained.
I have learnt a lot from this exchange and, since I have already acquired 3 battery charger
s over the years, I am reluctant to invest in another one only to measure battery
impedance. Question is now, does future potential use of such a charger
make better financial sense than simply throwing away the questionable batteries
and replacing them. Decisions, decisions.
One final question, what charge and discharge efficiencies would you expect from a new battery
past its "running-in" duration?
I am aware that mAh capacities are not based on any recognised standard, but I have been led to believe that the stated capacities of Panasonic and Venom batteries
are more reliable than most.