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Old 01-16-2009, 04:59 PM   #76
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Originally Posted by ultegrasti View Post
people should pay more attention to this pack and what it provides at its pricepoint. more than enuff for club racing w/o breakin the bank.

R

Actually some of our high end racers seem to prefer this pack over the 28C pack. Since the average voltage and IR is pretty much the same as the 28C pack and the C rate is lower it seems that the Chemicals get a bit warmer which results in good power in the limited motor classes. When using faster motors the higher C rate packs will have an advantage as they don't have as much voltage drop under load.
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Old 01-17-2009, 01:22 AM   #77
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Thanks Danny..appreciate this.

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Originally Posted by Danny/SMC View Post
Lipos shouldn't be stored with full charge as it will reduce capacity.

Check the voltage of the pack after the your run to prior to charging it. If it's 7.60 v or lower it will be ready for storage.

Here is the section on storage charge on our second generation charging/care instructions that will be inlcuded when we get our newest shipment of packs.

Storage:

LiPo packs have a very slow self discharge rate. This means they can be stored for long periods of time. The goal is to keep the cells above 3V to keep them from getting damaged. The standard has been 50% storage charge. This means a 7.4V (2 cells) pack should be stored at 7.6 volts. In some of our testing we have noticed that keeping the packs stored with more than 50% charge will reduce some of the packs capacity permanently. Serious car racers want their packs capacity to stay as high as possible. Our testing has revealed that storing them at 6.6 volts for a 2 cell pack will keep the capacity as high as possible.

If the pack is kept in storage for a long term (3 months or more), it is strongly recommended that the pack be preserved in a dry and low temperature atmosphere. For a pack stored at 6.6 volts we recommend you check the packs voltage every 2 months. If the voltage has dropped, charge it back up to 6.6 volts.
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Old 01-21-2009, 09:32 PM   #78
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Quote:
Originally Posted by Danny/SMC View Post
Storage:

LiPo packs have a very slow self discharge rate. This means they can be stored for long periods of time. The goal is to keep the cells above 3V to keep them from getting damaged. The standard has been 50% storage charge. This means a 7.4V (2 cells) pack should be stored at 7.6 volts. In some of our testing we have noticed that keeping the packs stored with more than 50% charge will reduce some of the packs capacity permanently. Serious car racers want their packs capacity to stay as high as possible. Our testing has revealed that storing them at 6.6 volts for a 2 cell pack will keep the capacity as high as possible.

If the pack is kept in storage for a long term (3 months or more), it is strongly recommended that the pack be preserved in a dry and low temperature atmosphere. For a pack stored at 6.6 volts we recommend you check the packs voltage every 2 months. If the voltage has dropped, charge it back up to 6.6 volts.
Danny, is the first thing a typo? Should it say 6.6v instead of 7.6v? Or do you mean to say anything in the 6.6-7.6v range is acceptable?
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Old 01-22-2009, 08:17 AM   #79
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Sorry for the confusion but what I mean is that the typical Lipo storage rate is 50% which equals 3.8V per cell or 7.6V for a 2 cell pack.

In our testing we have seen that a cell/pack will keep it's numbers closer to when it was new when keeping it stored around 6.6V so this is for the racers who want to keep the pack to keep it's numbers as good as possible.
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Old 01-22-2009, 08:54 AM   #80
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Danny, thanks for clarifying. Your knowledge is invaluable.

My pack is going to sit for longer than normal so I discharged to 6.6v on my ICE. I normally just leave the pack with whatever is left after my last run of the night, which is probably 7.4-7.8v.
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Old 01-22-2009, 09:03 AM   #81
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If you store it in a dry/cool place it can be stored for a few months for sure. You may want to check the voltage after a few months so see where it's at. You don't want the cells to go under 3 volts.
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Old 01-22-2009, 06:07 PM   #82
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Thanks Danny for sharing!

Last edited by stocker; 01-22-2009 at 08:19 PM.
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Old 01-27-2009, 09:30 AM   #83
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edit: it's already been answered.
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Last edited by M-Technic; 01-27-2009 at 09:49 AM.
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Old 01-28-2009, 05:28 PM   #84
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granted damn day indeed. I FOUND MY 4100!!!! Sadly after i bought 4 more lipos but hey, I FOUND MY 4100!!!!

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Old 02-24-2009, 02:06 PM   #85
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Iam totally new to the world of lipo.My question is this i got one of ure 4100 lipo packs and i got a new core charger so i tried it out last night and after 20 minutes or so of charging each cell read 4.0 volts im thinking the charge wasnt complete butt i was worried i might blow it up any help on what each cell will read when its fully charged thanx .
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Old 02-24-2009, 02:09 PM   #86
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If your charger is set on Lipo mode and for 2 cells you need to let it charge until it stops. The cells should be at 4.2v.
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Old 02-24-2009, 05:38 PM   #87
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Danny,
does anything bad happen if you don't fully charge the pack before using them? Does that count as one cycle too?
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Old 02-24-2009, 05:57 PM   #88
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That does do anything negative to the pack except it will have less capacity on the track. That would be considered a cycle as you will discharge the pack down.
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Old 04-05-2009, 02:28 AM   #89
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I know this is an old thread but I want to know about the 5200.

So my question is with a 17.5 is it even possible to tell the difference between this pack and the 28c? I want to be racing at a high level so it matters

Also does this pack have bumps on the bottom?
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Old 04-05-2009, 07:15 AM   #90
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No bumps on the bottom.

From what I have seen on our local track, there is no discernable difference in the 24c and the 28c pack (5200 vs. 5000).
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