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Old 08-25-2007, 07:54 PM   #1
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Default 40 amp matching!

TQ Cells is matching at 40 amps?

What do you think?
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Old 08-25-2007, 10:09 PM   #2
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I think the same thing that I think with any of the new sub-c cells, KA-BOOM
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Old 08-25-2007, 10:39 PM   #3
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Sounds like another attempt to make numbers look better to me. My local matcher said he did a test matching at 30 and 35. He saw no difference other then the way the numbers came out. Cell performance was no different. So I would say 40 is not going to do anything different either.
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Old 08-26-2007, 01:26 AM   #4
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The idea behind higher discharge rate isn't to produce better cells but to find the weaker ones

More stress while matching and you get what cells can take it and what can't.
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Old 08-26-2007, 07:00 AM   #5
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The idea behind higher discharge rate isn't to produce better cells but to find the weaker ones

More stress while matching and you get what cells can take it and what can't.
This is true but it will also drastically shorten the life of the cells that survive the matching process. No thanks, IB4200's go bad faster than a jug of milk already.
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Old 08-26-2007, 08:56 AM   #6
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Not to mention it helps their throughput. They can process more cells in the same time period and claim advantages to boot! (with the caveat that the amount of cells killed may offset any economical gain)

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Old 08-26-2007, 09:39 AM   #7
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I don't think reason IB are so fragile is their matching process! 2-5 cycles cells are getting from a matcher and then public gets them. After all when we run the cell discharge rate is way more than 30 or even 40A!!
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Old 08-26-2007, 10:08 AM   #8
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Actually I thought most motors only drew around 35Amps?
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Old 08-26-2007, 10:22 AM   #9
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Actually I thought most motors only drew around 35Amps?
And I don't think they do that at a continuous rate anyway, but thats the way they are matched.

Rod
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Old 08-26-2007, 11:10 AM   #10
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Quote:
Originally Posted by nnick View Post
I don't think reason IB are so fragile is their matching process! 2-5 cycles cells are getting from a matcher and then public gets them. After all when we run the cell discharge rate is way more than 30 or even 40A!!
Racing stock or 19T sedan is the easiest time in a cells life.

Cycling cells is harder on them (even at 30A) than running them in a car unless you are a world class open mod racer.

Also, IB4200WC cells are the most fragile cells since the Sanyo 1700SCE and Panasonic P-170.

All of the following will kill a IB4200:

1. Getting them over 150deg F (this happens all the time in 19T and Mod Sedan).
2. Over peaking....they get hottest a minute or two AFTER peaking.
3. Letting them sit on a shelf for 2 months without running them.
4. Running them them once in a mod sedan (if you are fast you will lose one cell per 6 cell pack every single run).
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Old 08-26-2007, 01:15 PM   #11
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Actually I thought most motors only drew around 35Amps?
Do the math... a typical 35 amp pack reads around 430. We run five minutes. Five minutes is 300 seconds. The batteries get much more abuse in the car than on the matcher. I always hear someone claim that the matchers want to use 40 amps to save time. Does everyone think that the matchers are out to screw the consumers? We take what we have to work with, go through it the best we can so the consumer does not end up buying bad cells, and enhance the performance by zapping. What is so bad about that? There is very little money to be made in the matching business. If we feel that 40 amps gives a better match and does not sacrifice longevity of the cell, we will do it. We have actually cycled cells at 40 amps once every day for two weeks straight with no decline in the numbers, so I doubt 40 amps kills the cells.

Adrian- you are right about a couple things, letting them sit is their worst enemy. ( Although the new ones are much better) Over peaking is also a sure fire way to kill a pack. However, running in mod won't necessarily kill the pack...DUMPING the car will. You do not want to dump a car with IB4200's.

Yeti35- why would it make the numbers look better? It gives LOWER numbers than 30 or 35 amp matching. When we went from 30 to 35 our sales dropped because we were putting out lower numbers that people were not used to seeing. The ONLY reason to do it is to try to extract better performance.
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Old 08-26-2007, 06:24 PM   #12
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Quote:
Originally Posted by Jeremy Otis View Post
TQ Cells is matching at 40 amps?

What do you think?
TQ has been on the cutting edge and winning races for many years. They do quite a bit of R&D and when they decide to come out with something, there is a good reason for it.

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Old 08-26-2007, 07:04 PM   #13
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Default 3800

This might seem like a stupid question, why couldn't IB stick with the 3800's? They were strong and stable cells and had lots of run time even when I ran mod, you know the old saying "If it ain't broke don't fix it". Don't get me wrong I love innovation in this hobby but as long as quality keeps up with the innovation. Just my .02
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Old 08-26-2007, 08:16 PM   #14
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They had to keep pace with EP and IP. A battle of one-upmanship. In this business, only the best performing cell survives.
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Old 08-26-2007, 08:24 PM   #15
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Same crap when 20amps went to 25 and then 30, 35 now 40 ect ect...

Matchers weed out the junk and cherry pick the good stuff so we dont have to do it our selves..... You all think the IB4200s are bad now? Imagine that we had not matchers at all, and you dropped by your LHS and randomly picked loose cells for your packs!! YIKES!! If they where GP3300s i would not be so worried.. But IB4200s??? No thanks, ill LEt SMC and the boys hit them hard first before i buy them...

the numbers are actually going to drop, the discharge curve is going to be lower because of the extra load...

One thing that would be intresting to see is a AVG VOLTS @ 300sec. This would be a nice standard used to compare numbers from brands XYZ. But again a 35 vs 40 amp draw would effect the numbers at 300seconds too. One gets hit harder so the 40's would look worse on paper initially.
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