Battery questionmilliamps?
10-10-2008, 01:44 PM
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Battery questionmilliamps?
Let's say one cell rechargeable ni-cad is 1.2 v and 1500mah.
If you hook 2 in parallel (+ to + and - to-) will it double the mah and keep the voltage the same?
Same for 3 equalling 4500?
Not considering weight, is this a better arrangement than using one high mah cell?
If you hook 2 in parallel (+ to + and - to-) will it double the mah and keep the voltage the same?
Same for 3 equalling 4500?
Not considering weight, is this a better arrangement than using one high mah cell?
10-10-2008, 01:50 PM
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RE: Battery questionmilliamps?
First part, Yes. Series doubles voltage, capacity stays the same. Parallel, as you indicated, doubles capacity, voltage stays the same.
Second part, better depends upon what you are trying to do. What are you intending this battery to do?
Second part, better depends upon what you are trying to do. What are you intending this battery to do?
10-10-2008, 01:59 PM
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RE: Battery questionmilliamps?
If you use either NiCad or NiMh in parallel, you must seperate them and charge them individually, i.e. you cannot charge them in parallel.
10-10-2008, 08:55 PM
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RE: Battery questionmilliamps?
Wow, there's a big drawback I never thought would happen. That's gospel I take it? I'm getting one big one. Separate charging sounds like a pita.
10-10-2008, 09:46 PM
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RE: Battery questionmilliamps?
ORIGINAL: Rodney
If you use either NiCad or NiMh in parallel, you must seperate them and charge them individually, i.e. you cannot charge them in parallel.
If you use either NiCad or NiMh in parallel, you must seperate them and charge them individually, i.e. you cannot charge them in parallel.
Why not?
KW_Counter
10-11-2008, 07:08 AM
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RE: Battery questionmilliamps?
You are of course correct that no two batteries are the same....but you charge multi cell battery packs in parallel all the time with out a second thought....is it really that big a deal.....after all a battery pack is just cells wired together
10-11-2008, 07:14 AM
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RE: Battery questionmilliamps?
You CAN charge them together....
and they MAY over and undercharge....
What I would do is cycle both batteries to get them all charged up...
then
build the "pack" and cycle that... a nice slow charge should keep the batteries very close to each other.....
we do it all the time with our receiver and tx packs 
and they MAY over and undercharge....
What I would do is cycle both batteries to get them all charged up...
then
build the "pack" and cycle that... a nice slow charge should keep the batteries very close to each other.....
Because the two batteries may not share the current equally during charge. One may overcharge while the other undercharges. Batteries are not identical, even two samples from the same brand.
10-11-2008, 09:03 AM
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RE: Battery questionmilliamps?
Charging battery packs is no problem because the batteries are wired in series, so the same current flows through each cell. Parallel is the problem. The cells may not share the current equally.
But yes, certainly packs can be charged in parallel, but it is not the best idea.
And no, we don't charge rx and tx packs in parallel. If you're referring to the common wall wart that comes with transmitters, the two leads are not in parallel.
But yes, certainly packs can be charged in parallel, but it is not the best idea.
And no, we don't charge rx and tx packs in parallel. If you're referring to the common wall wart that comes with transmitters, the two leads are not in parallel.
