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Old 11-19-2008, 05:08 PM   #46
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not all manufactors use the same test to get a "c" rating, so until that is done, its pretty much useless info when comparing lipos, that is unless someone is willing to take a sample of all the labels and run them through tests, and these 'test' batteries need to be random off the shelf batteries and not factory or label test batteries. IMO
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Old 11-19-2008, 05:09 PM   #47
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It doesn't really make sense for ROAR to worry about C rating or mAH hour as a manufacturer can submit packs with true C rate and mAH and then sell packs with lower C rate cells. Unless ROAR wants to start buying packs from every company from time to time to check as see what they are selling but that could get pricey.
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??
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Old 11-19-2008, 05:14 PM   #48
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Correct me if I'm wrong:

3T 540-size sensored brushless is less than 900W. LRP says its X12 3T is 797W but at what voltage? So lets say it is maximum 900W which at 7.4V makes 121A. When we consider ESC's internal resistance we can say that the MAXIMUM current can go up to 125A.

For 5Ah battery it has to be 25C to give out the 125A. So we don't need more than 25C capable 5Ah battery. Newer hardcase LiPos go up to 5300-5400mAh capacity. To get 125Amps from 5400mAh LiPo it has to be only rated at 23C.
and That's why I am happy with my 20c 3200mah li-pos! They still out perform a Nimh, and give me plenty of punch/ runtime running spec classes and mild to mid mod classes without taxing the battery.I personally think ROAR should put a cap on the c rating of li-pos @ 25c because for the time being it is all we as racers are going to need for quite a while.
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Old 11-19-2008, 05:15 PM   #49
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Originally Posted by skypilot View Post
not all manufactors use the same test to get a "c" rating, so until that is done, its pretty much useless info when comparing lipos, that is unless someone is willing to take a sample of all the labels and run them through tests, and these 'test' batteries need to be random off the shelf batteries and not factory or label test batteries. IMO
I'm actully thinking of doing such a test. If I do it I will be accused of bias so I may purchase the equipment and packs and let an independent person do the test.

Normally the industry standard is 90% but some do go down to 80%. If you read my first post some are way off and I have no issue with those who use 80% and say so. The problem is when you claim 35C and it's only 80% at 25C that is a big difference.

Last edited by Danny/SMC; 11-19-2008 at 05:45 PM.
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Old 11-19-2008, 05:25 PM   #50
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not all manufactors use the same test to get a "c" rating, so until that is done, its pretty much useless info when comparing lipos, that is unless someone is willing to take a sample of all the labels and run them through tests, and these 'test' batteries need to be random off the shelf batteries and not factory or label test batteries. IMO




Yet, SMC uses the same standard & prints C-rating on its Li-Po products .....
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Old 11-19-2008, 05:38 PM   #51
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I'm actully thinking of doing such a test. If I do it I will be accused of bias so I my purchase the equipment and packs and let an independent person so the test.

Normally the industry standard is 90% but some do go down to 80%. If you read my first post some are way off and I have no issue with those who use 80% and say so. The problem is when you claim 35C and it's only 80% at 25C that is a big difference.
just create a new screen name and have someone else type the info, many do


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Yet, SMC uses the same standard & prints C-rating on its Li-Po products .....
SMC has a standard for testing and printing labels it uses on its lipos? thanks for pointing that out, that is a good thing right.
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Old 11-19-2008, 05:42 PM   #52
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I still see a simple solution

MAX WATTAGE @ LOAD CURRENT

Example 1000W @ 135A

60 second test....average the sustained wattage.

Like I said, this test would not be a subjective test. It would be repeatable and easy to compare other batteries.

The C rating has no standardized test to compare C rating. Some use C as a safety barrier, others as a 90% capactiy limit.
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Old 11-19-2008, 05:43 PM   #53
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SMC has a standard for testing and printing labels it uses on its lipos? thanks for pointing that out, that is a good thing right.
Yes it is good news, just bad when SMC say`s others can`t be trusted, but their C-rating still is Ok ....
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Old 11-19-2008, 05:48 PM   #54
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I still see a simple solution

MAX WATTAGE @ LOAD CURRENT

Example 1000W @ 135A

60 second test....average the sustained wattage.

Like I said, this test would not be a subjective test. It would be repeatable and easy to compare other batteries.

The C rating has no standardized test to compare C rating. Some use C as a safety barrier, others as a 90% capactiy limit.
I don't understand what your testing method would achieve ?

So I would take a pack and discharge it @ 135 amps for 60 seconds then what would that tell me ?
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Old 11-19-2008, 05:51 PM   #55
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Originally Posted by Wild Cherry View Post
Yes it is good news, just bad when SMC say`s others can`t be trusted, but their C-rating still is Ok ....
Feel free to buy one of our packs with the proper equipment to discharge it at 28C and give us your results. It should look like the graph below.
Attached Thumbnails
False Lipo advertising-4000mah-graph.jpg  
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Old 11-19-2008, 05:54 PM   #56
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Yes it is good news, just bad when SMC say`s others can`t be trusted, but their C-rating still is Ok ....
I guess that depends if you just ran out and bought the "c" rating of the week battery or not.
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Old 11-19-2008, 05:56 PM   #57
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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....
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Old 11-19-2008, 06:01 PM   #58
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Originally Posted by Wild Cherry View Post
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....


Yes we use C rate as this is how Lipos are rated so what are you trying to say ?

No we have no plans on manufacturing a 35C pack.
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Old 11-19-2008, 06:02 PM   #59
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ok i was wonderin how liposuction was false advertising since ur taking away not adding. now it makes sense....

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Old 11-19-2008, 06:13 PM   #60
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So you don't mind paying for something your not getting as long as it has good IR and voltage ?
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.
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