Originally posted by holycow
I have more discharging questions...
I discharged my pack on my 16x7 at 30 amps, and it stops right about 5.4 volts. If I hook up my volt meter to the pack, in less then 1 second after the load is removed, the pack is up over 7 volts.
Voltage bounce. Batteries that have been discharged quickly do it, along with capacitors. It's an artifact of the chemicstry used in the cell and the discharge rate. It's normal, don't worry about it
Each cell is just about 1.2 volts. So I stick the pack on the tray, and let the blubs burn. Finally the first bulb starts to dim, and I read the voltage across that cell, and it reads about .95 volts. The second I take the blub out, WAM.. 1.2 volts.
Yup. Like I said, it's normal.
If I let a cell get down to .4 volts With the load, it reads .9 withOUT the load. So where are these cells supposed to be?
.9 with 1.2 without?
or
.4 with .9 without?
The generally accepted version is to discharge them to 0.9V in the tray and remove them, and they'll bounce back to 1.x V. (0.9 and 1.2 without)Be aware that the 1.2V you measured was
unloaded.
As NiMH cells discharge, they lose their ability to supply voltage under load, but not their ability to supply voltage open-circuit. When they get discharged, this is the kind fo behavior you can expect.
-dave