I have heard you are not supposed to do this, but most of the top racers a the track I race at do it to all of thier packs. In the opinion of most of the guys it adds a considerable amount of punch to the pack. Does anyone know why you are not supposed to do this and why it seems to add punch? Thanks

The main reason they don't recomend dead shorting is a liability issue.

I've always dead shorted the old long button cells with good results. When I got 4 new packs of short button cells I was a little reluctant and decided to do a little experiment. I dead shorted 1 pack right out of the gate and treated the others by just dischsrging to 3.60V and store. After all the packs had about 7 runs on I decided to cycle all the packs to see the results. Much to my surprise, there was no difference in runtime between the dead and non-dead shorted packs (they all had the same numbers to start), I expected the dead shorted pack would have lost more runtime but that was not the case. The dead shorted pack actually had the highest IR, and the lowest average voltage! In the past I had dead shorted packs only after they had begun to degrade and they turned into killer packs. Conclusion: dead shorting packs when new does absolutely nothing but lose runtime. I wont be dead shorting any of my packs until they start to drop off or after about 30 runs. the new 3rd generation 3300 cells will be out this month and I will do the same test on thosa as well...

dead shorting... its like chevy or ford. some swear by it.. some dont.

thing is.. if you dont do it right.... you can get hurt.. or cause a fire or mini explosion. i did it a couple of times, didnt see a difference really... well at least on the track i didnt.

if your a club racer, who races on weekend, just charge and discharge properly, and store them with a bit of a charge. really no BIG advantage.. and the disadvatages surely are more ... well bad.

im sure some will contradict or say otherwise.. if they seem to lose punch.. cycle them once or twice, or put them into your line of practice or qualifying packs.

i still use 2400'sa 3000's that work GREAT for practice and qualifying.

Ok. I'm confused. Higher IR and lower volts is bad, right? I tried dead shorting one pack of my year old, used hard tall button 3300's and had good results after 2nd charge. 1st charge took about 10mins longer to peak and were very flat. After discharging, traying and recharge they were killer. I agree with mayhem and wait until they start to degrade before dead shorting.

This is from their site:

FROM SMC WEB SITE

"Gold Peak GP3300SCHR NiMH

Charge:

We have been using a linear 6 amp charge rate with very good results. For maximum performance try to get your pack peak just before your race. If it has been sitting for awhile repeak with the same setup as the initial charge. If it's been sitting for 5 minutes or less repeak it with a .01( 10 mv ) peak detect.

Peak detect ( voltage threshold ):
-We use a .05 ( 50 mv ) for 6 cell packs.
-We use a .03 ( 30mv ) for 4 cell packs.

Discharge & Storage:

After the race discharge the pack down to .90 volts per cell. This equals to 5.40 ( 6 cell ) or 3.60 ( 4 cell ). Let the pack rest until the next time you plan on using them. Don't put them on a tray.

Cycling:

We are under the conclusion that cycling these cells brings no benefit other then determining if your pack has fallen off.

New charging updates for GP 3300’s

SMC is really growing at a rapid pace and we will continue to keep the best quality possible. We will not sacrifice quality even though we are producing higher amounts of cells.I have been testing many methods of setting up my matchers in the past 6 months or so. Here is the latest care info that we have been using on the newer high voltage GP's.1: After a run discharge the pack down to 3.6 (4 cell) and 5.4 (6 cell) let it rest until the next time you plan on using it.

Before you go to charge it put the pack on a pure resistor (no diodes) use a tray such as the Integy Indi Octane 2, for 2-3 minutes and then charge it.

This will improve the runtime by a few seconds and keep the voltage and AIR in good shape.

2: For those who aren't concerned about capacity you can use the following method

After a run discharge the pack down to 3.6 (4 cell) and 5.4 (6 cell) and then place it on the resistor only tray for 5 minutes or so then short the pack and store it shorted until the next time you plan on using it.

If you run your pack a second time in one day you should put it on the resistor only tray for 45 - 60 minutes and then let it rest until you are ready to use it again

This method will drop the runtime by 20-25 seconds but will increase the average voltage and may reduce the AIR."

END OF QUOTE FROM SMC.

I think they explain the tradeoffs of deadshorting.