Lipo confusion

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Old 08-12-2008, 03:39 AM
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Hi,
I was just wondering if anyone has tested their charger to see how well it balances the packs? The reason I ask is I am yet to balance mine, so I checked with a multi-meter and found one pack was one millivolt out and the other was two millivolts out(.002volts). So obviously no need to balance, but at what point should I? I assume that chargers don't balance down to one millivolt but has anyone actually checked? I have searched but found nothing. I don't want to test it on my nicely balanced packs to find my charger balances them worse than what they are now.
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Ben
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Old 08-12-2008, 07:20 AM
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Actually our 5000 has a bit better performance than our 4000. Here is the discharge graph of single cell used in our 5000 pack. The cell is a 2500 as our 5000 pack uses two 2500 cells in parallel and then those 2 cells are put in series (2S2P).
Attached Thumbnails Lipo confusion-2500mah-graph.jpg  
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Old 08-12-2008, 07:41 AM
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Danny,

I'm a club racer and will never see a big race. What pack would you recommend that will fit into a Type R with no modifications?

You were talking about a pack to replace a 4 cell in 12th scale, Can you explain more about this and when do you expect this to happen? Will it be the same size as a 4 cell is now?

Thanks
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Old 08-12-2008, 08:57 AM
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Ok since this thread has gotten a little contested at times let me preface by saying this is a question. No motives one way or another.

Danny you have stated the importance of capacity in the performance of packs. Why did you use 2500 cells in a 2S2P configuration rather than 5000 cells in a 2S1P configuration for your 5000 mah packs? Is there some benefit one way or another?
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Old 08-12-2008, 09:31 AM
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Originally Posted by lidebt2 View Post
Danny,

I'm a club racer and will never see a big race. What pack would you recommend that will fit into a Type R with no modifications?

You were talking about a pack to replace a 4 cell in 12th scale, Can you explain more about this and when do you expect this to happen? Will it be the same size as a 4 cell is now?

Thanks
You will be fine with our 4000. I believe it fits with no mods in the Type R but you may want to ask rcracingkid to make sure as he has experience with our packs in a Type R.

The single cell Lipo will be in a hardcase that is very close to the same size as a 4 cell side by side pack. We will have 4 sample packs at the IIC and we hope to have some demo runs on the track.
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Old 08-12-2008, 09:35 AM
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Originally Posted by padailey View Post
Ok since this thread has gotten a little contested at times let me preface by saying this is a question. No motives one way or another.

Danny you have stated the importance of capacity in the performance of packs. Why did you use 2500 cells in a 2S2P configuration rather than 5000 cells in a 2S1P configuration for your 5000 mah packs? Is there some benefit one way or another?

I think it has to do with our supplier not having any high C rate cells ready in the 5000mAh range and possibly the size of a single 5000 cell could not fit the ROAR maximum size. As far as I know this doesn't really help our hurt the pack by having 2 cells in parallel.
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Old 08-12-2008, 09:46 AM
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Originally Posted by Danny/SMC View Post
You will be fine with our 4000. I believe it fits with no mods in the Type R but you may want to ask rcracingkid to make sure as he has experience with our packs in a Type R.

The single cell Lipo will be in a hardcase that is very close to the same size as a 4 cell side by side pack. We will have 4 sample packs at the IIC and we hope to have some demo runs on the track.
I have Mike's old packs since he can't use them in Vegas.

Any preview for the general public now? Would like to see if they would work in my oval car.
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Old 08-12-2008, 04:00 PM
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are there any companys out there that make a weight to place under a lipo pack to help comensate for the weight difference?
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Old 08-12-2008, 04:06 PM
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Yep. Try here.
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Old 08-12-2008, 04:38 PM
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How does the 5000 Mah SMC pack fit into an associated B4 or a XXX-CR???
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Old 08-12-2008, 07:58 PM
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Originally Posted by Number09 View Post
Hi,
I was just wondering if anyone has tested their charger to see how well it balances the packs? The reason I ask is I am yet to balance mine, so I checked with a multi-meter and found one pack was one millivolt out and the other was two millivolts out(.002volts). So obviously no need to balance, but at what point should I? I assume that chargers don't balance down to one millivolt but has anyone actually checked? I have searched but found nothing. I don't want to test it on my nicely balanced packs to find my charger balances them worse than what they are now.
Thanks
Ben
Ben, I don't have experience balancing 2s packs. But, I do with 5s packs. With a 5s pack and a respected balancer (Thunder Power), I was seeing anywhere from 12 to 18 mV gap between lowest and highest cell in the pack. With a 2s pack, I imagine you can expect the balancer to get it within 10 mV. I think you're wasting your time balancing a pack that's within 10 mV - unless your charger monitors cell voltages for additional safety.
-Adam
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Old 08-12-2008, 08:35 PM
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Originally Posted by bshack View Post
How does the 5000 Mah SMC pack fit into an associated B4 or a XXX-CR???
LIKE A GLOVE! You do have to dremel a slot on the chassis battery spine but other then that it slides in, i have not removed my pack since the start of the summer, And with 13.5 i have done back to back bump up B to A main runs without recharging.
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Old 08-13-2008, 04:25 PM
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Any word on making a saddle pack that will fit in a B44.
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Old 08-13-2008, 04:28 PM
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At the end of this month were shipping out our new hardcase 4900/25C saddle pack. It will fit in all popular 4wd cars.
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Old 08-14-2008, 07:59 PM
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Originally Posted by Danny/SMC View Post
Our newest goal is to try and figure out how to get a single cell Lipo to work for 12th scale road course and this could also be adapted to oval if a slower class is required.
..i'm VERY interested in this............one cell Lipo..wouldn't even need a balancer...........will 540 size motors be ran with one cell?.....or smaller motors like in the 1/18th cars?............one cell with 18th size motors would probably= exceptional tire wear as the cars would be VERY light.......
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