9V Ni Cad's...Some Q's on re-charge time & topping off

[Darkflight]

Howdy!
I run Tesoro's. Silver U-max & an X2...

Finally got a pair of the rechargeable Ni-Cad. First question-how long to charge them fully?. I have a standard charger , on the bottom is listed 2X 9V---13mA.

Also-should I run them low before charging?. Or is it Ok to just top them off after a 4 hour hunt-wich is typical for me....

I have a multi-meter & I can read static voltage-is that a fair test of charge?


Thanks!

 

[Critterhunter]

Charge them first and then drain them dead with a flashlight or something. Do that over and over about six times to exercise the most capacity into them. Two or three times a year do this again to keep them in top shape. You can just top them off in between those 2 or 3 times a year that you drain them dead and charge 5 or 6 times.

You didn't mention if your charger has an automatic cut off. If it doesn't then divide the capacity of the cells by the MA output of the charger and that will give you roughly how long they need to charge when completely drained dead. However, if the charger doesn't shut off then I'd go past that length of time by about 2 hours because often nimhs and nicads hold a bit more capacity than they say on the label. It's not uncommon for a 1000ma pack to hold 1300 or 1400ma. If you bought those 9Vs in nimhs they'd probably have higher capacity as that's a rule of thumb over nicads in that nimhs usually hold more capacity, but remember you need a charger that is meant for nimhs then.

If you don't have a good charger than check out the Excal battery thread (about 10 pages long) in the Sovereign forum. We cover a great computerized charger for about $25 that you can't touch feature wise for less than about $125 in other brands. It'll do lipos, nimhs, nicads, and several other battery types. To charge hose 9Vs you'd just need to buy a $2 holder from Radio Shack. That thread covers various battery types, proper care, and features on this charger. It isn't meant for just the Excal as that was the original topic of the thread and has gone way beyond that. Do a search for "Accucel 6" in that forum and look for a real long 8 or 10 page thread. It's a long read but you'll be an expert on batteries and chargers by the time you're done.