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Discussion Starter #1 (Edited)
I'm using a competition electronics gfx lipo ready, with a Thunder Power 1cell 5000 mah 40c needed to know what amps i should be charging and all of the other settings should be on the charger. Im about 3 to 4 tenths a lap off the pace and the car is handling very good i'm not sure if i'm charging right. I'm charging at 5amps. I run in 13.5 cot class and if i dont get this straighted out i will not get 2 participate in Brl race coming up and it is about to run me so crazy im about to give up any help would be appreciated.
 

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I know some guys have been charging them at 2C which would be 10amps but I wouldn't see getting a racing edge by doing this. If anything, I would assume that it would be hurting the battery.
 

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You can charge all day long at 5 amps. No advantage with more amps. At 5 amps your battery will last a long time with little chance of ruining it. Your extra 10th's won't be solved by a battery.
 

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Just curiosity about lipo from an inexperienced lipo user,

Would cycling the battery once or twice say 1, 2, or 3 hours before the race help the pack any?
 

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Just curiosity about lipo from an inexperienced lipo user,

Would cycling the battery once or twice say 1, 2, or 3 hours before the race help the pack any?
NO CYCLING.
Cycling eats up battery life and makes the pack flat.

I take down .5-1 volt hour before a run at 15-20 amps.
Re-charge 10-15 minutes later.
Repeak 5 minutes before a race.
 

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ok im kinda curious here too.....im dog slow and know its not my packs but since i switched to lipo i have been constantly asking myself that it cant really be as simple as charge, run, repeat. lipos are great and user friendly but we are still dealing with a chemical reaction to produce power and there has to be a favorable method to extracting the most from this reaction. i have asked many racers and no one seems to be talking to much.....

maybe one of you seasoned factory type racers could walk us through your charge regimen and time frame

do people discharge after a run? down to what voltage?
what charge current?
do you repeak? and in what time frame before a run?
how many runs on a pack in a day before it feels flat?
are there any tricks to getting it to exactly 4.22 volts?
and the dreaded temp discussion... is it worth getting the pack to that 5* over ambient?

Maybe i am wrong but it seems to me there has to be a way to extract everything that is there and stay within the rules.....

thanks for any and all help
chris
 

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My understanding with lipo's is that you do not want to discharge them past 80% or else will harm the pack. I know this because I fly rc helicopters and have done lots of research on lipos batteries for the helis. You definately want to take care of them batteries, they're $400 buck a piece :) I really do not see an advantage to "topping" them off five minutes before a race but I could be wrong. As far charging a pack, most manufacturers say 1C is a safe charge rate (1C on a 5000mAh battery would be 5 amps) I know some companies are saying you can charge at 2C or 10amps.
Many guys say that they don't ever take the battery out of their car, they run it, then re-charge it right away for the second race. I'm not sure how good this is for the battery. For us, an average qualifer round takes about an hour. I personally don't think this is enough time to let the battery cool back down to room temp. (which is what the manufacturers are saying) and then to charge at 1C. There is not enough time. To me, I don't know why we aren't buying 4 batteries, charging them at home and not having to haul a power supply and charger to the track every weekend. That would give you one practice round, 2 qualifiers, and a main. That's what we do around here.

I am interested in seeing what other guys are doing. :)
 

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I run dirt short course truck, oval 1/10th Slider, Legend and run one battery. Charge it practice, recharge run qualifier, repeat, repeat, recharge run main. Never remove from car, never re-peak, and have not had any issues with this method in over two years. I charge at 1C and no more. Yes you can hit them harder and the new Lipos coming out are designed for 2C charging as I understand. Off road and Slider are 2cell lipos the Legend is 1cell pack. I store them with charge but not fully charged nor fully discharged.
 

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I really do not see an advantage to "topping" them off five minutes before a race but I could be wrong. As far charging a pack, most manufacturers say 1C is a safe charge rate (1C on a 5000mAh battery would be 5 amps) I know some companies are saying you can charge at 2C or 10amps.

I am interested in seeing what other guys are doing. :)
I should have stated also that I'm using the Competition Electronics Charger.

The Topping off charge is design to hold the lipo pack voltage at peek voltage
until the pack reaches 0 amp charge.
Maximizes voltage without overcharging.

I have tried just about every charger on the market.

If you race I suggest you look into the Competition Electronics Charger.
I think its the best charger money can buy! :thumbsup:

And I want to add that I'm not sponsored by them.
 
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