Quote:
Originally posted by Namuna
While you're doubling/trippling the voltage, you're also losing as much on the amperage...Those button batteries are actually LESS on the mAH rating than the stock NiCads!
|
That's the drawback to using this method, but if I'm understanding the Peak Charg'd thread right, it shouldn't matter much.
Until I read the peak charge thread, I figured that since a 50mah stock battery charges in 45 seconds, a 150mah NIMH should get charged three times. But it turns out that regular charging only fills up a stock battery a tiny bit.
FMZPLAYER1 calculated that a single charge on his z-car charger gave the car 11mah, much less than a stock battery holds. So in theory, a 50mAh NiCd could hold a triple charge just like a 150mAh NIMH. The longer run times after installing a 150mAh battery came from the fact that I charged it 3x and expected it to hold the charge. I had never tried charging the stock battery more than once.
Tinyrc found that a peak charged 50mah stock cell, just 10mah more than one of these, will run for about 45 minutes. If I can find a way to charge this 3-cell pack to its maximum capacity also, I could expect it to run for 4/5 of that, or 36 minutes, unless I'm misunderstanding something.
What I'm working on now is figuring out the easiest way to get the button cells charged to their max capacity of 40mAh each, or at least as close as I can safely get without detection circuitry. I'm already using an adjustable AC adapter @500mA, set to 3.0v for the dual cell and 4.5v for the tri cell. What I need to know is if this is enough voltage for each set of cells for them to get the full 500ma current. Then once I know the current for sure, I can figure out how long I need to charge at that current to get close to the max capacity. I imagine I will need to use a lower charging current to be safe, like 100mA or 300mA.
Any thoughts? I'm learning this as I go -- corrections welcome.
