Del-- your NiCad charger is probably fine. however, in the words of an EV battery guru "Batteries don't die, they are murdered". (I am guilty of battery homicide, well make that manslaughter, in my EV at present.) I'd check the batteries during charge and make sure they aren't getting too toasty. Also check that there isn't a gunky greenish blue crystaline growth on the positive terminal (where the vent is). And don't leave them in the charger for months.
A typical "end of charge algorithm" for both NiCads and NiMh is delta V over delta T or change in voltage over time. NiMh chargers typically terminates charge when the voltage goes flat, i.e., it ain't increasing any more. NiCad chargers typically terminate the charge when the voltage slope goes neagative, i.e., after a period of rising or steady voltage whilst under charge, the voltage suddenly begins to go down. Some chargers go to a trickle charge, some do not. Some chargers cut off if the heat is too high, some do not. Some shut off after a period of time, some do not. And some "condition" or drain a NiCad before beginning its charge in order to reduce memory effects in NiCads and some do not. |
