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Old Sep 05, 2006, 02:32 PM
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I'm wondering, if you use one of these on each 3s pack and then connect them in parallel, would the current rush still happen between uneven packs? Can the current pass easily back through these balancers?

Thanks, Terry
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Old Sep 05, 2006, 02:56 PM
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depending on how far off the voltages were would dictate the amount of current given off on cell to the other but why even use that device? Just plug the cells / Taps together in parallel with a "Y" splitter, of course your charging time will double as you doubled the total mah of the pack, therefore perhaps doing one at a time would be as quick. I am sure the device you listed works properly then you could hook up as many packs in parallel as you want and use any charger for charging/ balancing. The concern may be with a large inbalance the ability of that device to "bleed" off enough current fast enough to keep the cells below 4.2 volts no matter what.

Brian
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Old Sep 05, 2006, 03:03 PM
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I agree with Brian.

A major advantage of the parallel-charging method is precisely TO AVOID complicated machinery like balancers. Brian is also correct to point out that higher amperage chargers, or longer charging times, is a disadvantage. Pick you poison.

- RD
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Old Sep 05, 2006, 05:27 PM
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I guess I'm not following you. I was under the assumption that we were talking about parallel charging more than one pack. Are you guys just talking about parallel charging individual cells of one pack? I'm not sure that little "Cell Saver" is complicated machinery. I was just thinking that it might not allow current from one pack to rush into another. I guess I was looking for a way to charge more than one pack in parallel so that all could be charged in the same time it would take to charge one. I have used the little Cell Saver and I didn't notice any extended time for charging with it.

Quote:
Just plug the cells / Taps together in parallel with a "Y" splitter, of course your charging time will double as you doubled the total mAh of the pack, therefore perhaps doing one at a time would be as quick
I was under the impression that when charging multiple cells/packs in parallel, that you can add the total mAh and use that to figure the current, i.e. two 2000mAh packs in parallel could be charged at 4A. Am I wrong about this?

Seems easier to me to hook up the little Cell Savers than to have to rewire my packs.

Thanks, Terry
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Old Sep 05, 2006, 05:52 PM
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You're correct on all counts, Terry, as to series-wired, i.e. conventional, packs.

If you start out with individual cells (see posts 1 & 2), not conventional packs, there's no rewiring necessary.

- RD
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Old Sep 05, 2006, 06:49 PM
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Quote:
Originally Posted by RD Blakeslee
You're correct on all counts, Terry, as to series-wired, i.e. conventional, packs.

If you start out with individual cells (see posts 1 & 2), not conventional packs, there's no rewiring necessary.

- RD
Hi RD,

Thanks for clearing that up. I did read posts 1&2. I'm not ready to try making my own packs just yet. I guess I was under the impression that the little Cell Saver did charge the cells individually. That is what gave me the idea to use these as a way of paralleling several batteries at a time using the Cell Savers and it would "sort of" balance all of the cells at the same time, though I'm not sure it would work that way. I know the times I've used the Cell Saver and then measured the cells afterward, they were all exactly the same voltage. I only have one of them right now, but if this will work, I would buy more. Between my son and I, we will have several batteries going on the chargers all day at the field. Perhaps I would just be better off doing it the way I do now and just get a couple more cell savers. I have enough chargers to charge three packs at a time.

Blessings, Terry
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Old Jan 09, 2007, 03:18 AM
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oops, wrong topic
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Old Jan 09, 2007, 10:08 AM
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Quote:
Originally Posted by everydayflyer
I agree parallel charging and then series discharging would elimanate the imbalance issues and there are a few who take that approach.Charles
just a tack on note - parallel charging is how the balancing commonsenserc chargers works, perfectly balanced each charge. This is nothing really new, but always worth mentioning. charging through the taps is sure easier than rewiring the battery with powerpoles each time. tap that bat!
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Old Jan 10, 2007, 07:53 AM
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Actually, it's best to start with single LiPo cells, not conventional packs.

With conventional packs you have a point - after you've got all the adapters you need for all packs, and provided no cell fails in a pack. There's no easy way to replace a failed cell in a conventional pack.

Most of LiPo failure cost comes from having to replace a pack where a single cell in it has failed. That would be fine, if LiPos were a buck a cell, but they aren't.

- RD
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Old Jan 10, 2007, 08:19 AM
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which brings me nicely to the point ..
Where are the best lipo cells >??
I cannot find many dealer selling single cells ...
Also the choice,(different mah and c ratings) seem to be very limited
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