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Old 04-22-2013, 01:10 PM   #241
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Great way to sell more packs....
LOL!
The lipos come alive at charging 5C!!

I have a 2 cell lipo thats three years old and just turn the track record with it.
The internal resistance is as low as the day it was new...
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Old 04-22-2013, 01:19 PM   #242
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Is 20amp + charging limited only to full size packs? Or can the Shorty Lipo's be charged at the higher rates? And since shorty lipo's come in odd number mah amounts (e.g. 3800 or 4300) can you just simply "round up" when charging at 3c+? I.E. 4300 = 4.3 (1c), so 3c = 12.9amp (round up to 13amp charge rate?).
YES!

It seems that 12+ amps you start to see some benefits.
Lower IR.

Lower then 12 amps you need to cycle heat into the cells but IR gos up
as cells cool unlike the fast charging.
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Old 04-22-2013, 04:46 PM   #243
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It would seem that 5.55C charge for 12 to 14 Minutes is the way to go , but if your pack charges faster than 12Minutes at that charge rate, then you need to lower the charge rate... If your pack charges longer than 14Minutes at that charge rate, then you need to increase your charge rate...... It will need to be done on a fully discharged pack though (6.2v).....
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Old 04-22-2013, 05:04 PM   #244
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I would also round it down rather than up.....
My tp3200&3300 would need 17+ amps to 18amps....
My tp4200 would need about 23amps....
The tp5300 would need about 29amps...
Past 5300 mah to 7200mah you'll need more than 30amps, which my tp1430C can't do........... I'll need a higher amp power Supply to charge over 23amps , but will probably pass on the benefits and save a few bucks....
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Old 04-22-2013, 05:10 PM   #245
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I've bookmarked these links which might be helpful. I've yet to find guys who know more about batteries and chargers than these guys. "mrforsyth" is another one over there and him and Charles really, really seem to know their stuff.

1C charging of LiPolys is extremly out of date....

"The 1C max. charge rate was for back when LiPolys were rated atr max. of 6C discharge and there were no balancing leads ,balancers or balancing chargers..."

"...charging LiPolys at 3C and greater for over six years"
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Old 04-23-2013, 07:31 AM   #246
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What is the max discharge rate that the iCharger 4010Duo is capable of? Some places say 130W per channel, some say 40A. If my math is right 130W is ~30A with a 4.2v 1s pack.
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Old 04-23-2013, 08:13 AM   #247
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What is the max discharge rate that the iCharger 4010Duo is capable of? Some places say 130W per channel, some say 40A. If my math is right 130W is ~30A with a 4.2v 1s pack.
Mine has done a 1S at 36 amps fine. A 2S at 18 amps. You can actually set it for whatever discharge rate you want but it will max out at the 130 watts. But as the battery voltage drops the discharge rate will increase. Could be useful but I havent played with it much yet.



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Old 04-23-2013, 08:18 AM   #248
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Mine has done a 1S at 36 amps fine. A 2S at 18 amps. You can actually set it for whatever discharge rate you want but it will max out at the 130 watts. But as the battery voltage drops the discharge rate will increase. Could be useful but I havent played with it much yet.



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Do you dump your packs before rerunning them?

If you do, do you let them cool or charge right away?
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Old 04-23-2013, 04:16 PM   #249
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Do you dump your packs before rerunning them??
Only on the first charge or if they sat and cool down for a period of time.

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If you do, do you let them cool or charge right away?
Charge right away.
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Old 04-28-2013, 07:50 AM   #250
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A lot of you on here know Michael Bruce, on-road racer from Florida and one of the guys at Superior Hobbies. Yesterday a Lipo blew up in his face. If you're friends with his brother, Billy Bruce you can see the aftermath on Facebook. His face took a beating and the 12th scale he was charging his pack in is now just a pile of ash and melted plastic/carbon fiber.

I don't know how many amps he was charging at but for sure he wasn't using a Lipo Sack.

Just a reminder, be safe with your Lipos.
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Old 04-28-2013, 08:30 AM   #251
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wow, hope he'll be ok.
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Old 04-28-2013, 01:59 PM   #252
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A lot of you on here know Michael Bruce, on-road racer from Florida and one of the guys at Superior Hobbies. Yesterday a Lipo blew up in his face. If you're friends with his brother, Billy Bruce you can see the aftermath on Facebook. His face took a beating and the 12th scale he was charging his pack in is now just a pile of ash and melted plastic/carbon fiber.

I don't know how many amps he was charging at but for sure he wasn't using a Lipo Sack.

Just a reminder, be safe with your Lipos.
For sure! I'm going to invest in a lipo sack inside of a cash box!
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Old 04-28-2013, 03:22 PM   #253
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At the track I race at on Fri night, there was a lipo explosion, fireball about 2 1/2 feet round not sure on the specifics that caused it, but it was kind of terrifying. Was not in a lipo sack or bomb box. Pure dumb luck that no one was hurt at all, if the guy had been at his pit table things might have been rather different.
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Old 04-28-2013, 07:28 PM   #254
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Mine has done a 1S at 36 amps fine. A 2S at 18 amps. Yochannel actually set it for whatever discharge rate you want but it will max out at the 130 watts. But as the battery voltage drops the discharge rate will increase. Could be useful but I havent played with it much yet.



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If you have a dummy load (I.e light bulb discharger or resistors) it will do 1400w per channel , or 2000w synchronized mode. or you can do a regenritive discharge. So it can discharge at 476 amps for a 1cell............. really test those "c" ratings.
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Old 04-28-2013, 08:08 PM   #255
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Originally Posted by ground-round View Post
A lot of you on here know Michael Bruce, on-road racer from Florida and one of the guys at Superior Hobbies. Yesterday a Lipo blew up in his face. If you're friends with his brother, Billy Bruce you can see the aftermath on Facebook. His face took a beating and the 12th scale he was charging his pack in is now just a pile of ash and melted plastic/carbon fiber.

I don't know how many amps he was charging at but for sure he wasn't using a Lipo Sack.

Just a reminder, be safe with your Lipos.
Hope he gets well soon.

To be fair though - it looked like from the pictures that he wasnt using a lipo bag at the time considering the how fried the car was. Almost looked like the battery was being charged in the car without a bag.

Your comment and moral to the story are well taken though and good lessons for all of us.
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