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Old 11-25-2007, 01:33 PM   #61
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Reducing the cell size will do nothing to improve the cells in fact it will make them worse as far as reliability.

The key is to put into effect a maximum weight and leave the size as it is now. We have been running these slightly longer cells for 3 years now so it makes no sense to go backwards.

I really don't see how it can benefit racers to buy cells that are .5mm shorter that will be less reliable.
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Old 11-25-2007, 02:50 PM   #62
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I am actually surprised there is such a big deal being made about sub-c reliability when there is an alternative already here - LiPo. Why re-invent the wheel when much better batteries exist?

We should be looking at ways to integrate this technology into our rules an chassis designs while looking at ways to improve electric racing by going to longer races and improving race programs (bump-ups for example).

With brushless and LiPo, electric racing can be more desirable than ever. Going to lower capacity sub-c cells is a way to solve an immediate problem. But the fix is only temporary.

LiPo is the future. The problems with sub-c batteries is the signal to move forward, not backward.
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Old 11-25-2007, 03:50 PM   #63
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Lipo will come. EFRA has already aired their interest into including lipo in 2009. And if they ligalize it, BRCA will aswell and then it'll only be a question before every other organisation will follow suit.

I, for one, definately hope that happen. 8000mah, here I come!
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Old 11-25-2007, 03:51 PM   #64
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Originally Posted by Rick Hohwart View Post
I am actually surprised there is such a big deal being made about sub-c reliability when there is an alternative already here - LiPo. Why re-invent the wheel when much better batteries exist?

We should be looking at ways to integrate this technology into our rules an chassis designs while looking at ways to improve electric racing by going to longer races and improving race programs (bump-ups for example).

With brushless and LiPo, electric racing can be more desirable than ever. Going to lower capacity sub-c cells is a way to solve an immediate problem. But the fix is only temporary.

LiPo is the future. The problems with sub-c batteries is the signal to move forward, not backward.
Well said. I could'nt agree more. And your take on the 5 cell trend is?
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Old 11-25-2007, 04:43 PM   #65
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Once Lipos become legal for racing expect the samething that happened with sub-c cells as Lipo manufacturers will be pushing the limits to get more power which will most likely be at the expense of reliability and life expectancy.
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Old 11-25-2007, 07:19 PM   #66
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Lipo will come. EFRA has already aired their interest into including lipo in 2009. And if they ligalize it, BRCA will aswell and then it'll only be a question before every other organisation will follow suit.

I, for one, definately hope that happen. 8000mah, here I come!
The problem we have in the U.S. is that racers and promoters, for some, reason, do not want to follow ROAR rules. Or any rules set for that matter. They all want to make up their own rules to "personalize' their races and make them unique.

But anyway, enforcing existing rules now for one year (until Lipo) may not be the smartest decision. With TC popularity falling, another year of uncertainty could accelerate the decline. We will see.

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Well said. I could'nt agree more. And your take on the 5 cell trend is?
It has worked perfectly in the U.S. people choose to go 5-cell because they can perform better. Where it is mandated it seems to work well too.

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Once Lipos become legal for racing expect the samething that happened with sub-c cells as Lipo manufacturers will be pushing the limits to get more power which will most likely be at the expense of reliability and life expectancy.
I started racing in 1982. I had only raced for about a month when the first 1/12 World Championships was held in Anaheim, California (at the Disneyland Hotel). New to the hobby, I of course went to watch the best drivers in the World racing in my own back yard.

Only after the race was it known that the Jomac (they made cars) team figured out that if you used a new battery pack and charged it at a very high rate, you would get the best performance the first time charge. And after that, the battery was not as good (or junk, I can't recall).

The point is that racers and manufacturers have, from the very beginning, looked for any performance advantage even if it reduced the lifespan of the product manipulated.

We are at a point where the situation can't get any worse. LiPo is probably the best solution since that is the direction batteries are headed and where all development and improvements will be realized. But I doubt there will ever be truly equal batteries.
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Old 11-25-2007, 11:40 PM   #67
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Originally Posted by Victor Vector View Post
Thanks Sosidge.

Maybe some one can post pix of vent holes and their violations. We are talking defencive soldering here.

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i will bite, im bored.....here ya go

little background, new ib4200 wc.....sorry for the crappy cell pic, didnt wanna get my camera
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Old 11-25-2007, 11:50 PM   #68
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Holy crap if you are getting that much solder on there to cover those holes you need to take a soldering course.
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Old 11-25-2007, 11:55 PM   #69
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Rick, I really hope that your attitude towards NiMh is open to change...

If you run Off-Road or TC Stock/Spec, then you can go to LiPo. If you run 12th, Oval, 18th, or TC Mod, then the choice is likely to be NiMh, NiMH, or , er... NiMh. Even if you run Off-Road, you will have to buy a new car that can take the weight necessary to run LiPo - everyone here adds weights to their Off-Road cars over and above the kit weight already!! So LiPo only fits one part of one of the Electric Classes...

It is too simplistic to say that the future is LiPo when it is clearly going to cost each racer a lot of money and modifications to go LiPo, and LiPo doesn't help a huge part of Electric RC. What do you mean, you aren't going to do anything about NiMh and let half the market go? Why is your Company debuting the new 12L5 if there is no future in a more relaible NiMh cell?

It is essential that every manufacturer takes part in the NiMh debate, and is part of fixing the problem. It is also essential that you take part in preventing exactly the situations that you and Danny describe - abuse of the product in the name of performance. You could do that with NiCads and live to tell the tale, but that is not going to be the case with LiPo. There is a debate about NiMh reliability beause for most RC Classes there is no current alternative for us to race next month, or next year.

Your dismissal of the concerns that Danny and I have (irrespective of the size of the cell! ) is not something I would expect from someone representing one of our most respected manufacturers.
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Old 11-26-2007, 12:10 AM   #70
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...I've only read some of this thread, but I've also read so many that are discussions of NiMh vs. Lipo, etc.

Based on this you would think that R/C has ALWAYS run NiMh batteries...

Granted there are a lot of "NEWER" raceres that probably never ran the old NiCads...but when R/C switched to NIHM the battery technology has been moving at such a rapid pace...it seems every two months there is a NEW battery someplace in this market (Yes, a lot of them were not worth running...but they were there all the same)

2200 Green Nimh cells
3000's
3300's
3600's
3700's
3800's
4200's
4300's
4400's
4500's
now 4600's

At this rate...we should see 4800's by February and 5000's by next Christmas...

Do we really NEED THIS? Do the HOBBY Shops need this?

I was in my LHS this weekend...they have such a pile of 3000's, 3300's, 3600, 3700's still in stock..both in PACKS and individual cells...

Some dirty RAT at a Distributor made them think they NEEDED to stock this stuff..and now they are STUCK with probably 2500 - 3000 dollars worth of JUNK that Nobody will ever buy. (They have SMC packs that have been sitting there for almost 3 years they still want over $90.00 a pack for.

These guys are NOT really involved with RACING - they are a HOBBY SHOP that sells R/C Planes, Nitro Cars, Electric Cars and lots of other Hobby and Toy stuff. ..and we wonder WHY Hobby Shops go under.
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Old 11-26-2007, 12:29 AM   #71
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Holy crap if you are getting that much solder on there to cover those holes you need to take a soldering course.
it happens, i have people send them back that have half a roll of solder on em

problem is if a pack does blow up it usually gets thrown out and you cant pick the pack apart to see waht happend, i would have to say that most packs i have gotten back have been soldered wrong, tops melted, vents filled, solder gobbed on...
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Old 11-26-2007, 12:30 AM   #72
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I'm trying to get the IEEE Standard for sub-c cells as this is what cell manufacturers use as the guideline. It's my understanding that the standard is for cells to be 43mm max and cells need to be tested at 1c charge and discharge. This means 4.2 amps for 4200s. The problem is that cells will expand when subjected to high charge or discharge rates. It's my understanding that the current cells are at 43mm or less but once we charge and discharge them they expand and this is why cells are 43.2-43.8 mm after being used.


As far as Lipos go for racing the major problem that I see is that there are way more Lipo manufacturers which will result in pack of the month problem. I also see that Lipos have a memory effect and need to be cycled at high amp loads to keep high average voltage and low IR. Then you can charge Lipos in a certain way that makes them faster but unsafe at the sametime.

I really understand why some want to go to Lipos as the sub-c cell market has had it's shares of issues in the past 12 months or so but were finally seeing improvements that seem encouraging.

If you look at the results from Cleveland you will see that the lap times are very close and they have been very close in the last couple of years as there is plenty of good cells for everyone which makes races closer. Our guys used the IB4200s and we were very competitive even if our competitors were using 4600s.
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Old 11-26-2007, 12:47 AM   #73
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I also see that Lipos have a memory effect and need to be cycled at high amp loads to keep high average voltage and low IR. Then you can charge Lipos in a certain way that makes them faster but unsafe at the sametime.
That's interesting about the memory effect, I haven't noticed anything about that before.
Just when I was looking into lipos only because of a lack of NiMh availability at this time, all the more reason to wait for your new supply.
Thanks for the info Danny.
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Old 11-26-2007, 04:50 AM   #74
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Originally Posted by Jan Larsen View Post
Lipo will come. EFRA has already aired their interest into including lipo in 2009. And if they ligalize it, BRCA will aswell and then it'll only be a question before every other organisation will follow suit.

I, for one, definately hope that happen. 8000mah, here I come!
Ermmm... BRCA already has legalised LiPo, even if only for the 19t/10.5t class...
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Old 11-26-2007, 09:14 AM   #75
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Rick, I really hope that your attitude towards NiMh is open to change...

If you run Off-Road or TC Stock/Spec, then you can go to LiPo. If you run 12th, Oval, 18th, or TC Mod, then the choice is likely to be NiMh, NiMH, or , er... NiMh. Even if you run Off-Road, you will have to buy a new car that can take the weight necessary to run LiPo - everyone here adds weights to their Off-Road cars over and above the kit weight already!! So LiPo only fits one part of one of the Electric Classes...

It is too simplistic to say that the future is LiPo when it is clearly going to cost each racer a lot of money and modifications to go LiPo, and LiPo doesn't help a huge part of Electric RC. What do you mean, you aren't going to do anything about NiMh and let half the market go? Why is your Company debuting the new 12L5 if there is no future in a more relaible NiMh cell?

It is essential that every manufacturer takes part in the NiMh debate, and is part of fixing the problem. It is also essential that you take part in preventing exactly the situations that you and Danny describe - abuse of the product in the name of performance. You could do that with NiCads and live to tell the tale, but that is not going to be the case with LiPo. There is a debate about NiMh reliability beause for most RC Classes there is no current alternative for us to race next month, or next year.

Your dismissal of the concerns that Danny and I have (irrespective of the size of the cell! ) is not something I would expect from someone representing one of our most respected manufacturers.
I don't think I ever said we should ignore NiMH. My opinion is that we should not spend so much time and resources with NiMH when there is another technology here NOW that needs addressing.

PERSONALLY, I think that integrating LiPo into R/C racing is more important for the long term health of electric R/C racing than worrying about NiMH cell dimensions and the possibility that this MAY solve a problem.

If there are unsafe defective NiMH cells on the market, ban them.
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