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Neglected IP3800's - need some batt experts to read this for me please. >

Neglected IP3800's - need some batt experts to read this for me please.

Neglected IP3800's - need some batt experts to read this for me please.

Old 04-10-2007, 05:02 PM
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Default Neglected IP3800's - need some batt experts to read this for me please.

ackground:

Good used JOE 3800 IP packs. Extremly happy with the performance. Been away from racing for 2-3 months. Never pulled the batts out from the case. After reading XRC's batt care article - decided to pull the batts out. They were strored as per the article with 10-15minutes charge in them.

Guess what - voltage was less than 3 volts for the pack and took multiple attempts to even get a charge in the pack (was not false peaking - rather was a low voltage issue with the pack/ICE). I was able to put 500 Mah and it would trip off - I toasted them at 30A and trayed to 0.9V. Did that multiple times. Never was able to get more then 500-700 MAh in.

Got home today and decided to try again - got ~3750 at 7.87some volts. To the touch - a couple of cells felt noticebly warmer than the others. Took out the infra red and measured just as the batts peaked. Starting with the cell at the positive side I got the following temps...

1 - 105F
2 - 98.5F
3 - 114F
4 - 153F
5 - 149F
6 - 116F

During my attempts to "revive" the pack - I noticed that cell #2 was always reaching 0.9V immediatly while the others took a while and *somewhat* clicked off at the same time.

Considering all of this - any explanation for the ~150 temp reached by cells 4 & 5?
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Old 04-10-2007, 05:39 PM
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i would say the pack is dead.
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Old 04-10-2007, 05:43 PM
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Sounds like Cell #2 is dead/dying and is messing up the rest of the pack. I would take cell #2 out and cycle again.

-James
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Old 04-10-2007, 05:46 PM
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it sounds to me like you now have a practice pack, I wouldnt say its trash
Me unlike many think the IB cell is fairly durable. as long as the cell isnt just plain dead meaning 0.00 then its good enough to run.
I would get some cycles through a car and see how the temps are after you do that 4 or five times. I have had many cells reach different temps during charge and the battery still run pretty good.
hope this helps
Mo
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Old 04-10-2007, 05:48 PM
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Time to do some 4cell racing dude.

I think your problem was how you tried to revive it..

I have heard many people say that when you leave 3800+ batteries for a while you have to be VERY gentle in bringing them back.
Trickle charge it for a day or two.. or at most a 1-1.5 amp charge rate. Then use only a equalizer or the discharge function of the charger at no more than 5-10 amp. Once or twice and it should come to life.

this is what I have read from more than a few..

I am still running 6 year old 2400 nicads in my son's car.. and I am still getting 2200 mah in them.

James
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Old 04-10-2007, 05:53 PM
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yeah - I think I muscled them up a little to much.....since I run 1/12th as well - its not as much as a piss off.

These IP's sure make me enjoy my well used GP3300 that you can't killed.
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Old 04-10-2007, 05:56 PM
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BikerBob - I plan for my first "away" race to be the big race in Jan. at Fastcats - hope to see you there.
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Old 04-11-2007, 08:34 AM
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About 3 months ago my three 3800 packs started to take no more than about 400 0r 500 mah, altho they'd been regularly used until that point. I think I'll try Bikerbob's suggestion.
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Old 04-11-2007, 08:55 AM
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I have had pretty good luck using the syntac 35 amp pack disharger, It brought back my 3800 that were setting for 6 mos. some totally discharged and brought back my 3300 that were setting for over 6 mos.
the cell voltage and run time are as good or better according the display read out. I averaged around 1.24-1.25 volts per cell after discharging. ran good on the track.

the discharger pulse discharges at 35 amps so the batteries never heat up, heat being the enemy, it takes several hours to discharge a pack.

my friend has a trinity individual cell pulse discharger, it takes about one hour per pack.
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Old 04-11-2007, 11:01 AM
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Originally Posted by c-lyon
About 3 months ago my three 3800 packs started to take no more than about 400 0r 500 mah, altho they'd been regularly used until that point. I think I'll try Bikerbob's suggestion.

This one is more puzzling to me??

I would worry about a dead cell in the packs.. but if all three packs are doing it.. hmmm

The new Trinity DPD might be what you need to see if these packs are ok?

I am sure someone at your track went out and bought one... see if they will put the packs in for you so you can get and idea of what each cell is doing.

Packs used regularly should not do this unless something IS WRONG.

Good luck!!

James
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Old 04-11-2007, 11:15 AM
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Seems like I got the same problem as CaliberX on my ib4200. They can only receive 1400 mah in it. But the IR when discharge is nt too bad 62mOhm. Mine is a stick pack, guess i'll just use it for practice.
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Old 04-12-2007, 09:14 AM
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Hey. I have 12 IB3800 race cells. I have cycled them 2 times as single cells. How would you match them up,by average volts from dis-charge or by run-time? Dan
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Old 04-12-2007, 07:19 PM
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Runtime in my opinion (thats what I do with all the used packs I buy off the local "connected" batt guy.
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Old 04-15-2007, 10:42 AM
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Thanks for the above info. i have been charging these 3800's at 5 to 6 amps and delta peak of 5 mv/cell like SMC says to. My question is if I'm only getting 3100 to 3300mah in them with peak temps of 89f to 100f,(SMC says 140f)should I continue to increase the delta peak #'s to maybe improve there capacity? They are only practice packs and have lost some punch. I've read in the ice charger forum that some guys go as high as 10 m/v cell. I do have the temp sencor and it set at 124f.what do you think? Dan.
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