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A couple notes on the conditioning process are in order:
Caution: Not ALL cells respond to Dead Shorting. In fact it can adversly effect the runtime and voltage of your pack. Be sure to check our forum to make sure the cell you are using responds favortably to Dead Shorting.
1) Make sure the pack is completely discharged before connecting the "dead short" wire. Use a "zreo" discharge tray to take each cell down to 0 volts.
2) Connect the "dead short" wire fairly soon after you discharge them. If using a tray, connect the wire before you remove them from the tray.
If you don't the voltage can build back up in them. Most dischargers DO NOT discharge a pack down to zero volts. You MUST reset your discharger to do this and if it is not able to do so, use a bulb discharger to bring them COMPLETELY down to zero volts.
3) When charging the packs, you may get a false peak during the first few minutes. Just restart your charger. Or you can take the "dead short" wire off a couple hours before charging as this seems to eliminate most false peaks.
I know... you are wondering just what this conditioning method does? I've been able to get some actual test completed and have found that:
Pack runtime increases an average of 5 seconds. Not a big deal, but we pay quite a bit more to get only a few extra seconds.
Lowest runtime increase seen was 3 seconds.
Highest runtime increase was 10 seconds. The higher runtime increases are generally rare with most in the 5 (or less) second range.
Voltage increases can vary greatly but have the potential of offering the greatest performance increases.
Out of 5 packs that I have data for, some have small increases from 1.132 volts to 1.146 volts per cell.
Most increases took packs into the mid 1.15 voltage range.
One pack's voltage increased from 1.151 volts to 1.171 volts per cell!!!
All tests were run using a CE Turbo 30. I have heard from people using this method for a number of months and none of them have reported any damage to their packs. It would seem that the stock class drivers can benefit the most from these methods as it has the largest effect on voltage.
As always, I just pass on tips and tricks that I hear about. Your results can be different then what I report here and I will not assume any responsibility for use (or misuse) of these tips and tricks."
I think the gp 3300 and the 3700 are good to dead short for stock and 19turn racing but not good for mod!! the new ib3800 have been proven better not to be dead shorted for any type of racing thougt i would just share some info on what i have heard.I dead short all my pack except the 3800 and have good luck with all of them
Dead shorting is a very legitimate theory and works well if used in the right way.
NASA and the military still use this type of battery maintainance today.
A nicad cell loves it and the early nimh cells would tollerate it without major run time losses.
With todays high-tech advances in capacity and voltage it probably isn't worth the time and effort and kills the cells capacity.
The biggest thing I see about "dead-shorting" is that a pack should NEVER be dead shorted , I don't care if you tray to 0.0 overnight then put a wire across the pack , DON'T DO IT !!!
The ony way to dead-short is to jumper each cell individually .
If you have many 0.0 trays , you can just leave them there all week , if not build your self some dead short wires with alligator clips to short each cell , a very cheap alternative to 3-4 trays.
Experiment with a single pack before you attempt any of this as todays nicad's are hybrid cells and don't like it , you may even kill some cells.
Been there , tryed that , but unfortunately thats the only way you know.
If its a pack you care anything about then don't do it !!!!!!!!!!!
The runtime loss will be huge , like 100 sec plus and the small voltage gain if you put the discharge curves over the top of each other will be minimal.
You can gain faster lap times other ways without ruining your batteries.
To quote Hank , check with your battery supplier for advise, as they have alot more experience than us.
My good 3800 + 4200's have never seen less than .50 per cell for just a few minutes.
Using the Much More CTXD you can dead short your pack and the CTXD will deadshort each cell down to zero volts.
I have played with deadshorting IB3800's and 4200's. The results were very intersting. While testing with my "new" CTXD I accidentally deadshorted a 3800 over night. The pack lost about 40 seconds of runtime but gained a ton of voltage. You may say this is typical when deadshorting but here was the big difference.
I chart my voltage on every pack every 15 second through 300. The deadshorted 3800 pulled more voltage for the first 60 seconds than it had done before deadshorting.
Here are the numbers on a few 3800 6-cells. Cycled at 6.0 amps, single peak, discharge at 35 amps, 5.4 cut-off.
Non-deadshort Deadshort
Run 407 370
Volt 7.20 7.27
@1V 7.23 7.29
IR 12.8 12.6
As you can see deadshorting the packs does help. The second set of numbers only had the pack deadshorted for 1 hour. Before charging I deadshorted the pack for 1 minute and then went directly into a charge. Track performance was also noticable. I was able to pick up a full tenth of a second up front. I then geared the car down a tooth so it ran the same number up front as before. The car finished better but still ran big numbers up front.
This is just my findings. I have not deadshorted any 4200 SHV or Worlds Edition cells so I'm not sure how they will handle to the deadshorting.
New pack's after build, Novack adj. tray to .05 then charge at 6 amps for 500 sec.'s
At the track,first pack discharge at 25 amps, equalize to .05, charge at 6 amps. till fully charged (23-2700) sec.
Coming out of car after run, discharge at 25 amps, equalize to .05, charge at 6 amps for 500 sec.
After a couple of mos. of racing you can cycle (At MFG. Spec.'s) your pack's to see what you have. ONLY CYCLE EVERY 2-3 MOS.
My good 3800 + 4200's have never seen less than .50 per cell for just a few minutes.[/QUOTE]
I killed some 3800s dead shorting. my new 4200s will never be dead shorted.
I did sort of the same test with one of my 3800's and they came out about the same...... except mine were 4c..... Now my only question would be how much longer will that pack last, months wise compared to one that never gets deadshorted and raced everyweekend.......... I can post at a later date my findings from the test once I find that sheet of paper, LOL, justmoved so give me a week or so, LOL.......
But the greatest thing I saw was runtime loss and down to about 300 sec also not real noticeable if even any loss, I really dont care what the pack does after that point since I only race for 240 sec...................
__________________ Team DCM -- Darrell Clevenger Motorsports dcmotorsports100@hotmail.com Yeah were still out here, just took a break for military reasons!!!!!!!!
I am currently dead shorting my 4200's. I cant race every weekend, and at times they have went pretty low on voltage. According to my battery guy. He said to start dead shorting them. I was amazed at the results. My voltage increased, my RT went from actual 350+ sec to over 400+sec, the IR went down. And now I am getting a ton more mAhr in them. I would only recommend this to cells that have fallen past the low voltage marks, not new or good cells that havent had this happen to.
Just my 2-cents worth.
Kevin
Last edited by glgraphix; 11-06-2007 at 08:07 PM..
My good 3800 + 4200's have never seen less than .50 per cell for just a few minutes.
I killed some 3800s dead shorting. my new 4200s will never be dead shorted.[/QUOTE]You want to be very carefull i had a brand new 42000 blow up in my face NEWcells are junk
Its been over a year since this post. I know have been dead shorting all my cells.I recently bought new cells and deadshorted them right off. Ive seen alot of new cells blow up. Not any of mine. Guess ive been lucky.
