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Old 02-16-2008, 11:51 PM   #61
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I wonder how heat not generated through the charging/discharging process will effect the performance of the cells? The 140F you are seeing is due to the discharge/charge cycle, correct? So if you used an external heat source to bring them to a controlled temp, and then measure any difference in performance, mabye the very high discharge/charge rates wouldn't be necessary.
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Old 02-16-2008, 11:52 PM   #62
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Originally Posted by Danny/SMC View Post
To discharge a Lipo you need a discharger that can be set at a 3 volt cutoff per cell so for a 7.4v pack you stop discharghing at 6 volts. I believe one of the keys to make the packs perform better is to get them warm/hot. So far by using a 35 amp discharge on a fully charged pack I'm seeing good results. The temperature is 140 degrees. I'm going to purchase equipment that will allow me to discharge up to 100 amps to see if helps the pack some more.

If your serious about racing and plan on racing for awhile I would reccomend you by a Competition Electronics Lipo T35GFX. This is a great charger/discharger.
I run offroad and usually run 2 or 3 classes and 2 or 3 GFX's aren't really user friendly to lug around.
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Old 02-17-2008, 12:00 AM   #63
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Originally Posted by WheelNut View Post
I wonder how heat not generated through the charging/discharging process will effect the performance of the cells? The 140F you are seeing is due to the discharge/charge cycle, correct? So if you used an external heat source to bring them to a controlled temp, and then measure any difference in performance, mabye the very high discharge/charge rates wouldn't be necessary.
Please don't attempt any of the tests I'm performing or use a charge rate higher than 1C. Never warmup your Lipo packs. Doing any of this can result in fire and can be dangerous


I'm trying to figure it out but it's pretty tough to test. As soon as I do have info I will post it.

I know that using a 12 amp charge rate over a 5 amp charge seems to yield better results. This is without warming the pack up.

When doing back to back cycles I see the best improvement which I believe is related to the heat build up from the discharge. I will be trying to heat up the packs prior to charging them to see if the results are the same.

Last edited by Danny/SMC; 02-19-2008 at 12:14 PM.
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Old 02-17-2008, 12:02 AM   #64
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I run offroad and usually run 2 or 3 classes and 2 or 3 GFX's aren't really user friendly to lug around.
Please don't attempt any of the tests I'm performing or use a charge rate higher than 1C. Never warmup your Lipo packs. Doing any of this can result in fire and can be dangerous

You don't need 3 GFXs. You only need one. Just set it to charge your packs at 12 amps which is pretty fast and you discharge them at 35 amps. One GFX can easily do this.

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Old 02-17-2008, 12:03 AM   #65
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You don't need 3 GFXs. You only need one. Just set it to charge your packs at 12 amps which is pretty fast and you discharge them at 35 amps. One GFX can easily do this.
i'll def. be looking into this then
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Old 02-17-2008, 05:36 AM   #66
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You don't need 3 GFXs. You only need one. Just set it to charge your packs at 12 amps which is pretty fast and you discharge them at 35 amps. One GFX can easily do this.
So you're recommending charging the packs at 3c !!!??? Sorry if my lipo ignorance is showing.
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Old 02-17-2008, 07:51 AM   #67
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If you want your Lipos to run faster then charging at 12 amps seems to help a bit plus it cuts down on charge time. Once again this is just what I have found out while testing.
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Old 02-17-2008, 11:01 AM   #68
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I'm waiting for EA to get your new lipo packs. Then when I blow them up, I can blame you. JK. Can't wait to get the new stuff. Thanks.
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Old 02-17-2008, 01:06 PM   #69
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Oh, and by the way Danny I'm one more person who would be interested in seeing you guys release a saddle pack!
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Old 02-17-2008, 02:36 PM   #70
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I believe we will do a saddle pack but it will take a bit of time as we need to get tooling for the cells then once the cells are done we need to get the mold for the casing.
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Old 02-17-2008, 09:43 PM   #71
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Only 3c? ca-mon, step up to the plate. everyone in the know is charging at 10-12c minimum.
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Old 02-17-2008, 09:51 PM   #72
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I believe we will do a saddle pack but it will take a bit of time as we need to get tooling for the cells then once the cells are done we need to get the mold for the casing.
that will be sweet
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Old 02-17-2008, 10:55 PM   #73
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Only 3c? ca-mon, step up to the plate. everyone in the know is charging at 10-12c minimum.



10 and 12C is not reccomended plus I have never seen a Lipo charger that charges past 12 amps.

Last edited by Danny/SMC; 02-19-2008 at 12:08 PM.
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Old 02-18-2008, 06:47 AM   #74
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10-12c is easy to do, take that silly little electronic monitoring device out of the equation, and plug directly into 12v source! j.k. please dont try this PPl.
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Old 02-18-2008, 07:16 AM   #75
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Hey Danny, can any discharge device be used to discharge at 35amps with 6v cutoff? Or only the GFX lipo version? I ask this because a friend tried to discharge one of the Orion lipos a few months back. I think it was either 30-35amps on a GFX. But the leads got hot very quickly! So he cut it off real quick. Just curious.
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