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Old 11-19-2008, 06:20 PM   #61
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So how come this whole "C" rating thing was never big with Nimh?

Shouldn't the cells be all about matched, high av, low ir, high mAH and mWH?

Maybe i'm confused about wtf "c" rating is anyway, the cells ability to discharge?

Then the higher "C" means lower resistance, right?

So why not put a label on each cell like in the good old days with all the info competitive racers need?
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Old 11-19-2008, 06:21 PM   #62
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From the way the lipos are going, it would make sense to me that a company like Competition Electronics would jump on board and make another standardized matcher like their Turbomatcher. Obviously not for actually cycling to match individual cells, but to be able to cycle lipo packs and print labels that we all got used to seeing and reading.

Maybe even be able to put the true C ratings on the packs, along with the AV, IR and runtime.
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Old 11-19-2008, 06:26 PM   #63
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I don't mind not getting something I'm NOT NEEDING. What difference does it make if my 5000mah pack is 25C (125 amps continuous) or 30C (150 amps continuous), when my car is drawing maybe 20 to 25 amps average during a race? I don't think even a full throttle standing start will spike over 100 amps in my situation.

Everything I've ever known leads me to look at voltage, IR and runtime to determine how my packs will perform on the track. You discolsed those numbers on every NIMH cell I ever bought from you. All I'm saying is I'd like to see everyone selling LiPO's disclose those same numbers so I can make an informed choice.

I understand it's not like you can put eight LiPO cells into a turbomatcher (I[m not even sure if a Turbomatcher has the settings range to do this, after all you can't take a LiPO down to .9 volts, and I KNOW the Turbomatcher can't safely charge a LiPO cell, so there is definitely a logistical problem facing you if you want to do this...

I also know that higher C ratings usually indicate lower IR, but I'd just like to see a move toward publishing the numbers that actually matter to me...

Would it make sense to choose my real car's tires based on whether they are H rated (SAFE TO 130MPH) or V rated (safe to 149 mph) when I'm driving a car that will never see the better side of 80mph? Or would it make more sense to look at skidpad numbers to comparison shop (if I'm looking for the highest grip) or mileage numbers (if I'm looking for longest life)??? Suppose I bought H rated tires that tested to be grippier than some other set of V rated tires? Would I worry that i was paying for something I wasn't getting No, because again, it's something I don't need.

I understand what your saying but if companies are selling packs with inflated C rate they could also sell packs with inflated numbers but if they are GFX numbers many do own one to see how close the numbers are. With C rate you need 2000 dollars worth of equipment to pull that kind of power.

When we first released our 28C packs we decided to put the numbers on them and we thought others would do it but it seems like no one wants to do it so were considering not printing them anymore.
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Old 11-19-2008, 06:28 PM   #64
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I would of thought ROAR would see this is a safety issue.

Perhaps ROAR should do this occasionally , Seeing they are the Governing and ruling Body , It would only have to be at random and structured into the approval costs.

As menttioned i do beleive the "C" rating issue is more important that seeing if a hard case meets a drop test??
Getting true C rating out of a battery is not a safety concern. Dropping a battery in the pits, putting it on a charger or in a car and catch fire because of damage from the drop is a safety concern.

huge difference between the two.
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Old 11-19-2008, 06:28 PM   #65
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Originally Posted by a_main_attendee View Post
So how come this whole "C" rating thing was never big with Nimh?

Shouldn't the cells be all about matched, high av, low ir, high mAH and mWH?

Maybe i'm confused about wtf "c" rating is anyway, the cells ability to discharge?

Then the higher "C" means lower resistance, right?

So why not put a label on each cell like in the good old days with all the info competitive racers need?

Sub-c cells have always been rated by capacity.

Lipos have always been rated by C rate and I don't think the RC car market is going to change this. There is nothing wrong with ways Lipos are rated what is wrong is that some companies are claiming certain C rates which aren't true.
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Old 11-19-2008, 06:29 PM   #66
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Originally Posted by sprint5h View Post
From the way the lipos are going, it would make sense to me that a company like Competition Electronics would jump on board and make another standardized matcher like their Turbomatcher. Obviously not for actually cycling to match individual cells, but to be able to cycle lipo packs and print labels that we all got used to seeing and reading.

Maybe even be able to put the true C ratings on the packs, along with the AV, IR and runtime.

They already have this it's called a T35-GFX Lipo and that is what we use to print the info on our 28C packs.
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Old 11-19-2008, 06:33 PM   #67
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Danny, Just because others aren't doing is not a good reason to quit. Continue to be a leader. Don't lower yourself to their level, rise above and stay on top. Keep informing your customer as as you are in this thread and continue to produce and sell the best with pride.
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Old 11-19-2008, 06:43 PM   #68
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See there Danny , you use C-rating , yet condeem others for doing the same ...

Thats the bad...

BDW do I need a hotplate to heat your product before testing ?

I have no doubts SMC will be manufacturing 35c real soon ....

Then do the same like now when the other company`s comes out with a 40c....
I think you are missing Danny's point. Yes SMC uses a C rating on their packs. He is not condemning others for also using C ratings. He is condemning them for using FALSE C rating's on their packs.

I have known Danny for a long long time and have witnessed him taking money out of his pocket and buying other packs from the hobbyshops. When I asked him why he simply replied that he just wanted to make sure that he (SMC) was offering batteries that were as good or better than the competition. He always wants to have the best cells available and just because we now have Lipo's does not change that.

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Old 11-19-2008, 06:44 PM   #69
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Great thread Danny!!! Please keep printing pack's numbers!!! Don't stop doing this!!! It is making a big difference and setting the bar in how we buy Lipos and we couldn't be happier with your products...SMC Packs are the best packs in the business today and we really appreciate your honesty and dedication to provide us with super products. Everyone at our track has them now and we do notice and big difference in performance and lap times after using your packs!!!
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Old 11-19-2008, 06:53 PM   #70
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Originally Posted by a_main_attendee View Post
So why not put a label on each cell like in the good old days with all the info competitive racers need?
In the good old days, a matcher would have a climate controlled room with a bunch of turbomatchers in it, and when they'd get a shipment of cells they could process a whole bunch in a workable time frame.

Turbomatchers won't work with liPO's, they can't charge them and from what I remember of mine, there's no way to set a discharge cutoff voltage that would work with a LiPO cell.

That leaves a matcher in the unenviable position of running every LiPO cell on a Turbo35GFX to get similar numbers... it would take forever (or a crapload of Turbo35GFX's, not an attractive proposition) to process a batch of LiPO cells, because a Turbo35 GFX can handle one cell at a time, where a turbomatcher could handle 4, 6 or eight at a time depending on which models you had.
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Old 11-19-2008, 06:55 PM   #71
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Originally Posted by EAMotorsports View Post
I think you are missing Danny's point. Yes SMC uses a C rating on their packs. He is not condemning others for also using C ratings. He is condemning them for using FALSE C rating's on their packs.

I have known Danny for a long long time and have witnessed him taking money out of his pocket and buying other packs from the hobbyshops. When I asked him why he simply replied that he just wanted to make sure that he (SMC) was offering batteries that were as good or better than the competition. He always wants to have the best cells available and just because we now have Lipo's does not change that.

EA
Have not miss the point , and still say when SMC introduces its 35C they will howl same as now when the other`s come out with 40C.....

If SMC says C-ratings are not truth full, why even
use C ratings on their products ?
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Old 11-19-2008, 06:59 PM   #72
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Have not miss the point , and still say when SMC introduces its 35C they will howl same as now when the other`s come out with 40C.....

If SMC says C-ratings are not truth full, why even
use C ratings on their products ?
We will not release 35C packs.

C rate is the way to truly rate a Lipo and we use this and take this very seriously. I guess you have troubles understanding when I explain myself.

This thread is about warning the racers/cosnumers about false C rates.
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Old 11-19-2008, 06:59 PM   #73
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Getting true C rating out of a battery is not a safety concern. Dropping a battery in the pits, putting it on a charger or in a car and catch fire because of damage from the drop is a safety concern.

huge difference between the two.
I havent a problem with this statement( 'TRUE C RATING) But we are talking about 'falsified C Ratings" If you have a pack stated at 20c / 3200 mAh = constant of 64 amps

If you therefore use this pack with a discharge current of 64 Amps it shouldnt be a problem BUT if this was only a 12c or even 15c labelled at 20c you would consequently be over discharging the pack, Which in effect could cause a thermal run away due to over heating. ie cell fire,

To me this is aslo a safety issue, This test should be performed as an approval .

How hard would it be to perform this basic tests on submission.
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Old 11-19-2008, 06:59 PM   #74
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Quick note to Danny...

Please don't take any of my comments in this thread as slams at you or SMC, I've never had anything but complete satisfaction with anything I've bought with the SMC label on it... I know it's sometimes hard to read intention in a forum posting, so I wanted to make sure I'm not misconstrued here...
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Old 11-19-2008, 07:00 PM   #75
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Have not miss the point , and still say when SMC introduces its 35C they will howl same as now when the other`s come out with 40C.....

If SMC says C-ratings are not truth full, why even
use C ratings on their products ?
I may be able to answer this one-
people will buy the biggest, think about it, if one says 25, and the other says 30, bigger is better right?

its all marketing, true numbers or not.

Remember the old panasonic 3600's? they sucked!! yet, people still purchased them because they where "bigger" than 33's, regardless of actual cell facts.
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