# Dead-Shorting 4600's



## NCFRC (Aug 4, 2005)

When your dead-shorting 4600's , how long are you leaving or have left them
dead to still have them come back and run strong ?


A day 

A week 

A month

Months


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## inman20k (Aug 28, 2008)

NEVER, You should not dead short batteries it will kill the run time. Yes, your avg. volt might be better but that is because your run time is shorter so the batterie might feel good but it will fall off faster. And yes it might make a pack that sucks before you dead short better but that is partialy because you are killing the other cells. But to ansure your question any amount of time if fine once you tray them down and put on a jumper wire just let them cool all the way. For at least an hour or two then just charge them slow at about 2A fo half cap. then charge full at about 5-6 amps the bat will work fine. But you will neaver hals to do this if you always keep your batteries full and re-peak once a week.


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## racerj3 (Feb 25, 2008)

i was always under the impression that once you dead shorted a pack you had to charge it right away.


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## NCFRC (Aug 4, 2005)

I've dead-shorted a green cell 4600 4 cell pack twice over night and before
doing this it discharged at 3694 mah.

After 1st dead short - 3750 mah

After 2nd dead short- 3766 mah

240 sec. and 300 sec. voltages both improved

Ir went from 8.5 to 7.1

   


I've never seen this with a 4200 pack , it turned into a paper weight.


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## DOUGHBOY (May 7, 2008)

you are not going to hurt your packs.. the most damage you might do will be done to the run time but most of these batteries have over 400 seconds of run time. and last time i checked we dont run 7 or 8 minute races.. you want to leave them dead shorted for atleast thre days and on the morning of your race day cycle your packs twice to wake them back up and your batteries will be better than when they weree new.. lower IR higher voltage little less run time... dead short them


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## katf1sh (Jan 17, 2002)

dead shorting works well...

once you start dead shorting a pack you can never go back...

once you remove the wire you place the pack on charge...

when done place pack in 0-30 tray for about a half hour depending on the amount of charge left in the pack

i always shorted the pack out with solder (it melted like a fuse if charge was left in pack) i never shorted new packs..i gave them about a month of racing before i started shorting them...

not every pack reacts the same to shorting though..some never improved..others loved it..


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## CClay1282 (Jan 5, 2006)

Well you cant just jump a lead across them and take them off the tray. The cells will want to come up in voltage so the stronger cells will pull the others into negative voltage. I use novak flatline trays (or the like) to keep each cell at 0v. Then to wake them up, i just pull them out of the tray, charge for 2 min at 6 amps, then bring them back down with a 0-30. Then equalize with smart tray. Then fully charge. That is right before i want to run them.

i have packs that are 4 month old now and the AV is 5.00 to 5.02, IR is 5.7 - 6.2, runtime around 400 sec on all four of them. WAY better than when they were new. They run strong on the track too!

These were all energ 4600's

I had two energ 4600 6 cell packs too
AV 7.49
IR 10.8 and 10.9
Runtime 403 and 405

They ran really strong too!


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## NCFRC (Aug 4, 2005)

3rd Dead-Short on this Energy 4600 4 cell pack,,, was only shorted over-night.

IR went from 7.1 to 6.8

Discharge Mah went from 3766 to 3808

So far , it works great on these cells :thumbsup:


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## ToddFalkowski (Aug 31, 2006)

You can certainly dead-short cells. You lose runtime, but gain voltage, and drop IR's. 

Deadshorting will help bring back cells that have been sitting, etc.


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## casper60 (Feb 10, 2008)

I started deadshorting with my latest batch of packs and they seem to get better every week. I throw a set of lights on them to DC them, once out for a couple minutes, I have a wire with ends that slide over the tabs so i don't have to solder. I don't touch them until I run them again.

Side note, I ran a pack in practice last night that hasn't been used in a couple months. Was just as good as my other packs.


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## 67-4-fun (Feb 23, 2004)

deadshorting new batteries works well, it does not work well with older packs that have been cycled differently, used packs don't seem to respond to deadshorting that much if any at all, in fact they may get worse. so if you have new cells and that I mean less than a month old you should be ok, as long as you pay attention to what you are doing and MAKE SURE!! each cell is at 0 volts!!!! and that there is no cell voltage reversal.. just my 2cents..

JP


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## NCFRC (Aug 4, 2005)

I agree as this four cell pack I've been experimenting with started out as a five cell ,, but the first dead-short one cell never came back from 0.0.
I now have a great 4 cell pack and it does wead out the weak ones.

I've been hitting it with 8 amps and it gets no hotter than at 6 amps.


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## ToddFalkowski (Aug 31, 2006)

See, I've seen just the opposite with deadshorting old cells. Now, if the cell is junk (maintains no voltage, and acts as a "pass through" in packs) then nothing brings it back. But, I've had many that I've left for dead, deadshorted them, and brought them back to life.


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## NCFRC (Aug 4, 2005)

I'll have to experiment with the couple cells that are at zero and see if I can get them to respond.

My experimenting so far with dead-shorting a ener G 4600 pack has shown that the pack has leveled out and " IS NOT " getting worse on every cycle.

I don't have exact data on the same pack not dead-shorted ,, but what I did test that way always showed your first cycle the best and then it deteriorated
rapidly from there.

This dead-shorted pack has consistently discharged at 3880 for the last few cycles.:thumbsup:


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## CClay1282 (Jan 5, 2006)

I have found that my numbers are pretty consistant. They fluctuate a little, but not far off. They have been dead shorted since i got them 4 months ago, and they are still as good now as they were on the second cycle.


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## trailranger (Feb 9, 2006)

I'll be honest, I never dead shorted untill this week. My last oval race was in September, and I had 4 almost new packs sitting with partial charges go bad. I cylced them and every one would peak at 3500 to 3900mah of charge. Discharged to .90V tired again and same results.. the PACKS were flat.

Pissed that I had $200 in dead batteries with less than a dozen charges each I dead shorted my cells using A 0-30 then integy trays to 0.0V. This was a act of desperation, but the results were better!!!

3 of the packs now take 4700mah of charge, and on pack is still holding back at 3800 because of a bad cell.

I have access to a battery zapper, should I go all out and Defiberlate that flat EP cell?. So when do you zapp a battery? Right after peak? Right at .90V (30A discharge) or at 0.0V? 

Next how much voltage? Zappers go up to like 90V, but 90V is scary deadly. What about 30V?


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## bojo (May 6, 2002)

I zapp batterys before I charge them.


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## NCFRC (Aug 4, 2005)

I havn't been able to get some weak cells to respond after going to zero , they
sit at 0.00 and won't come back ? Can't be an open circuit as when you try to charge your charger says .301 and then falls back to 0.00 when disconnected.

But this great 4 cell pack sits at zero for days and comes right back.

Still feel that Dead-shorting the Ener G 4600's works good ,, but it will KILL your weak cells , where if they maintained a charge they'd hang in there longer.


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