Hi group,
I have an experiment under way to measure the performance of a Duracell Procell AA battery.
The test setup
a) HP3478A DMM for voltage measurement
b) HP6060A electronic load for discharge current
The test and data logging is being performed by a PC using HPIB.
To compress the data, the time and voltage are recorded when the battery voltage changes by more than 5mV, rather than recording the data at fixed time interval.
In addition every time the voltage changes by more than 50mV, the load is turned-off for 4 seconds. The battery voltage is measured twice while the load is off. This additional data point can be used to calculate ESR.
The DMM leads and load leads are connected directly to the battery, (Kelvin connection).
Starting with a fresh AA battery, I am now 40,000 seconds (11 hours) into the test and the battery voltage is 1.1V, this is with a constant load current of 150mA.
Here is some preliminary data, from a partially discharged cell, gathered while I was testing the software:
I should have good data later today.
Regards,
Jay_Diddy_B