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Old 09-29-2003, 06:08 PM   #1
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Default Dead shorting batteries

Hey
i tryed something new on all of my stick batteries last night (1 RC2400SP, 3 3000sanyo's, 2 GP3300 matched SMC stick packs). What i did was discharge then dows to 2.6v ( duratrax digital Peak charger dishcarges down to that auto) @ 10amp then again @ 2 amp to drain as much as i could out of then then i put a bit of metel over the pos and neg terminals for about 1 min, then on the charger and put:
2400 = 240mah
3000 = 300mah
3300 = 330mah
into them and left them for the night.

this morning ( i live in australia) i did the same as last night with the discharging and shorting them. out i am now in the process of charging them @
2400 = 5.5amp
3000 = 4.8amp
3300 = 6amp

i tryed this on an OLD (like 2.5 years) cheapy $10us 1700 last night and it peaked @ 9.43v and took 1901mah charging at 3.6amp which is pritty good (well i think so) does the lowish peak voltage mean that the ir has lowerd. because before i did this the 1700 was peaking at around 10.50v.
can any one tell me if im going to stuff up my batteries in going this, or am i going the batteries better?
thanks
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Old 09-29-2003, 06:16 PM   #2
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i heard dead shorting nicds would help, but im not sure about nimh! i never heard anyone dead shorting them and was told not to. nimh doesnt like dead shorting!
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Old 09-29-2003, 06:20 PM   #3
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i will post my results as the batteries charge
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Old 09-29-2003, 06:27 PM   #4
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dead shorting nimh's is not a good thing, but for nicads i think that used to be how to get more punch out of them(i havent run nicad's in a long time)
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Old 09-29-2003, 06:29 PM   #5
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1.5 year old 3000 # 1
peak 9.32v
2891mah
4.8amp charge

any coments on those numbers
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Old 09-29-2003, 06:38 PM   #6
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Default Dead shorting batteries

Quote:
dead shorting nimh's is not a good thing
If you read the latest info from the SMC site, they will tell you otherwise.

I have personally tried the Dead Shorting technique and was not pleased with the results. Though my Packs are only about 2 months old.

Currently, I discharge @30a to 0.9v at the Track. Store, then tray my packs the night before the next race. This seems to provide consistant performance weekend after weekend.
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Old 09-29-2003, 07:01 PM   #7
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hmm
yeah all my batteries becides my 2 Gp3300's are atleast 1.5 years old my gp's are 3 months but im lloking at getting new batteriees any way so i thought wat the heck

does any 1 know why they are peaking so low compaired to before??
they are now peaking at 1700 = 9.5
3000 = 9.3

would it be that with i shorted them it lowerd the IR???
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Old 09-29-2003, 07:19 PM   #8
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second 3000
peak volt 9.45

2785mah

4.8amp
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Old 09-29-2003, 09:46 PM   #9
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SMC has been dead shorting new 3300 with good voltage increasing results..


I not sure your analizing the right things here though. First off you cannot properly equilez and discharge a stick pack to be dead shorted. Your bound to hurt your stick packs. Proper dead shorting involves using a proper discharging tray and then shorting out the entire pack..

Unless you have a Charger that can cylce your packs you cannot really start to compare results of dead shorting before and after stats. The numbers your posting a of very little use as peak voltage and mah of charge tells u nothing of the packs abilities. Also im not sure why your charging all those different packs at different amp rates?

You should be chargin all packs at 6amps. Just about every matcher is matching with 6amps and thats with 3300s back to 2000s and 1700s.

Anyway to get usefull test results you need to cylce your packs and look at comparing:
run time
average volts
ir

EXAMPLE @30amp discharge:
RUN TIME= 400
IR= 17.9
AVERAGE VOLTS= 7.02
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Old 09-29-2003, 10:04 PM   #10
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A buddy of mine deadshorts his nicad battery packs. He gets great punch out of them....great for stock racing. Although, I think runtime goes down. As for nimh, I havent heard any good things out of deadshorting them.
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Old 09-29-2003, 10:21 PM   #11
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Default Re: Dead shorting batteries

Quote:
Originally posted by acid_rain182
Hey
i tryed something new on all of my stick batteries last night (1 RC2400SP, 3 3000sanyo's, 2 GP3300 matched SMC stick packs). What i did was discharge then dows to 2.6v ( duratrax digital Peak charger dishcarges down to that auto) @ 10amp then again @ 2 amp to drain as much as i could out of then then i put a bit of metel over the pos and neg terminals for about 1 min, then on the charger and put:
2400 = 240mah
3000 = 300mah
3300 = 330mah
into them and left them for the night.

this morning ( i live in australia) i did the same as last night with the discharging and shorting them. out i am now in the process of charging them @
2400 = 5.5amp
3000 = 4.8amp
3300 = 6amp
i tryed this on an OLD (like 2.5 years) cheapy $10us 1700 last night and it peaked @ 9.43v and took 1901mah charging at 3.6amp which is pritty good (well i think so) does the lowish peak voltage mean that the ir has lowerd. because before i did this the 1700 was peaking at around 10.50v.
can any one tell me if im going to stuff up my batteries in going this, or am i going the batteries better?
thanks

AHHHHH! Never, never, never, never use a discharger that discharges the entire pack as a whole and bring it down that low!! You run the serious risk of reversing cell polarity and ruinng your packs! If you want to do that you need to use a discharge tray that discharges the cells individually. If you're not racing or serious about batteries (especially with NiMH) just do the normal discharge methods and skip dead shorting.
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Old 09-30-2003, 02:03 AM   #12
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hey the reason im charging at differant rates is becuse the OLD 1700 pack wont eben take 4.5 amps it just fulse peaks non stop ( on any charger)
i will let u kno whow well they run later tonight ( i race tonight) hopefully they will run well
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Old 09-30-2003, 02:20 AM   #13
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i would not recommend shorting out any batts bcause of the damage caused is so much long term.
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Old 09-30-2003, 06:00 AM   #14
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iszit impt to discharge at 30 mAh??? wat if i discharge it only at 20 mAh?
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Old 09-30-2003, 06:05 AM   #15
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Guys,

Check out http://www.smc-racing.com

Go to "New charging updates for GP 3300's" (middle of the page) and click on "Read More"

This should help explain a few things.

Thanks,
Mark
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