I know that most people here are not fans of recharging disposable alkaline cells, and I agree. Self discharge rate is high, batteries are WAY more prone to leak, and rechargeables are efficient more than ever before. I have lots of good LSD NiMH cells and a late generation Maha C9000 that I use everyday. Consider this question just for experimental purposes.
I have a cheap, POS charger that does not have specs concerning voltage output or "charging finished" voltage termination for primary cells. In fact, it does not terminate at all when it thinks the battery is charged, the LED just goes from red to green. You've probably seen this charger before, it's the Sierra Electric JB5411 "Super Charger". RRIIIGHHHHTT.....
Notice the charing specs aren't listed....
Now, this charger does have short-circut protection and individual cell charging, but the benefits ends there. The charging light turns green when an alkaline cell reaches 1.35 volts, which makes me think that the charging routine for alkaline and nimh/nicd cells is not all that different. My guess is constant current regardless of battery chemistry. I've heard from several people that charging primary cells requires slow pulse-charging and pole switching every 5 pulses (or something to that effect) to keep the excess gases from building up and rupturing the weak seals in alkaline and zinc-xxx clhoride/carbon cells.
I want identify the charging rates of different cells in this charger to see what's really going on (ie: voltage, current, pulse vs constant charging, etc.). How would I go about measuring the voltage on the charger terminals? When a battery is not present, the AAA/AA/C/D bays measure 8 volts, but when a cell is inserted, the voltage drops. Taking the current change in consideration, how would I go about accurately measuring the voltage the charger puts out for certain cells without getting the cells voltage interfering with the measurement? Will I have to measure a component inside the charger while a battery is being charged?
Hopefully this is not an overloaded question... I am happy to clarify if that is the case.
Thanks for any input!