Charging NiCds - Can you charge while enclosed

[bill marks]

I have two questions regarding NiCd battery packs.

I know you never charge a lead acid battery in a closed space such as a WTC. Can you charge NiCd batteries in a closed WTC?

I have three NiCd 7.2 volt battery packs. One is 3000 mah and the other two are the same but of unknown capacity. Can I operate charge and discharge these battery packs in parallel. It seems to me that since they are in parallel, their voltages will have to be the same and that terminal voltage indicates the state of charge, they will all charge and discharge at the same % of their capacity. Any experience?

Bill

[seasub88]

Bill, May I suggest that

Bill, May I suggest that you go to your nearest hobby shop and go to the rc auto (cars) section. Those guys are real experts at recharging batteries. And don't let their young ages fool you. They know the subject.

Shocking, isn't it? jim

[bill marks]

Good idea bbut I live

Good idea bbut I live up in the back country of New Hampshire. The nearest hobby shop that handles anything but craft supplies is an hour and a half away - but, hey, I could call them. Thanks.
Bill

[fung pang]

never, NEVER, charge any battery

never, NEVER, charge any battery in a close space, or put a just charge, still hot battery in a wtc!

it may explode!

please, play it save.

fung pang

[bill marks]

Fung,
Thanks. You advice agrees exactly

Fung,
Thanks. You advice agrees exactly with a NiCd tutorial I found online. NiCds will out gas hydrogen and oxygen in an explosive mixture if the battery is over-charged in a closed space. I also found that you can charge and discharge batteries of differing capacities (not differing voltages) while in parallel. The tutorial recommended periodically trickle charging at C/10 every third charge to remove any unbalances in indivual cells or packs.
Bill

[petn7]

well, it's not really worth

well, it's not really worth the effort of trickle charging that frequently. If you raced 1/10 scale r/c cars or trucks, sure, it's necessary, but then again, those people pretty much put in a new motor after every race. sub don't require that kind of performance, nor do they require that kind of longevity from batter packs. i mean, 1500mah nicad battery that drops to maybe 1300mah after a year...so what? those batteries cost $10 from the start.

and don't get me started about efficiency...



Edited By petn7 on 1071676186

[surge]

I am a newbie, but

I am a newbie, but I know a little about this. Well, more NiMH than NiCad spiral wound cells, but they aren't *too* different.

If you charge slowly, I bet you are fine. These cells aren't like wet NiCad (or wet lead acid), they are encased in metal. If they evolved hydrogen and oxygen gas at evey charge then you would need to water them, like you do wet batteries. I would think you would want a slower charge with good charge termination control (temperature, voltage, timer)

PS, I live in NH, too.

[petn7]

speaking of charging rates, the

speaking of charging rates, the slower you charge your battery packs the more juice they'll have; another good reason to slow charge, eh?