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Thread: While testing Elite against others we found big C Rating trickery

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Old 10-04-2010, 02:54 PM   #1
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Default While testing Elite against others we found big C Rating trickery

I apologize in advance to be so winded. There is alot to absorb. But good info.


Since the beginning of our business we have brought in product only if it meets our standards. We will get samples, test them, and if they check out we stock them. I know that we are not considered a huge name brand, with big flashy adds and claims, but we have always had a reputation for carrying inexpensive, high quality product.


We have been out of some good crawler lipos for a while. Now we have found some stuff that really shreds. The power is impressive!. We decided to get a secret shopper, have him/her order up some packs that people are commonly using for crawling. Then we tested them all under the same conditions. Our findings were actually very surprising. We expected to see good results from the brands we brought in and just advertise that we were as good as these brands but at a lower price. Our findings were shocking!

We discharged all the packs(or cells rather) under the same conditions. We applied a constant load and recorded voltage over MAH. This showed us how high the voltage was under load and how much MAH the pack delivered at a 3v cutoff. This is similar to the industry standard for testing lipos. We started testing at 20C (well below the max ratings of all the cells) and we were shocked to see the known brands did not perform well even at a fraction of their labeled C rating.

Note: The other brands brought in, were dissected and I soldered directly to an individual cell, to have more accurate results. We did not discharge as a complete pack rather individual cells. Running single cells is going to give better results for all and does not bias one brand over another. Keep in mind that when testing packs as a whole it introduces variables, such as build quality and materials used, into the mix. To remove said variables we only test single cells.



Subjects:
Elite 850mah 25C
Elite 1000mah 35C
Elite 1300mah 35C
Brand P 860mah 50C?
Brand P 1100mah 50C?
Brand X 850mah 45C








Brand P:

Although both brands results were a little shocking, this brand, that we will call brand P, was especially shocking. We got an 860mah 2S, and an 1100mah 2S pack in. Both claim 50C max on the label. This brand doesn't seem to believe in C ratings as per their site so it was hard to figure out if 50C was a burst or constant rating. The 860 had a normal discharge curve, but performed poorly. The 1100 on the other hand, was terrible. At a 20C load, it tanked to 100mah then was done. I had a hunch that the cell had a really high IR, so I opted to do a 10C load. It actually had a somewhat normal curve but performed extremely poorly considering we had to go to 11amps to make it even compete with the rest of the cells. The Elite had much higher voltage at twice the amperage. This was a sure sign that the cells were only about a true 10C cell.

Both the 860 and 1100, got extremely hot. Whereas Brand X and Elite were room temperature which is another sign of high internal resistance, and low C rating.

In crawlers, these could still work fine, and have proven to supply *adequate* power. But why pay for what is being labeled as a 50c when in fact it is barely a 10C?





Brand X:


Brand X is a well known brand as well and has been around almost since the beginning of lipos. They have good packs, so we were shocked to see that our 25C cell out performed it. It is an 850mah 45C cell but ours had better runtime and slightly better voltage too. We thought that perhaps, the cells would kick ass at 40C+, but instead, the curves got much worse. This cell is a 20C at best. The cell build quality is superb, BUT, the C rating is way overrated.


-------------------------------------------------------------------------


I am going to post clearer curves. I know there is alot to read. The blue curves are the 3 Elite cells. The green is Brand X. The red is Brand P 860. The black is the very poor performing Brand P 1100mah @ 20C and 10C. Obviously the small black curve is the 20C test for Brand P's 1100mah. As you can see ,the 850 Elite and the Brand X are close. The Elite actually out performs the Brand X a little and is about 30% cheaper.





So what does this all mean? Well:

A: Higher voltage under load = more power and runtime. (Volts * Amps= Watts)
B: The Elite cells are cheaper than both brands P and X, and out perform them in power.


A basic way to understand your batteries is to think of a light bulb. They are rated in watts. The higher the watts, the more light they produce. Well this is true for batteries. The more watts the pack can supply, the more power you get. This is pretty much a horsepower rating for batteries.

Volt's x amp's = watts.

On the discharge curve above, the best example is the Elite 1000 compared to the Brand P 1100 mah. For the Brand P to even register, we had to decrease our starting testing load to 10C(11amps). That pack produced 38.5 watts under load. The Elite produced 71 watts under twice the load. As you can see the Elite produced TWICE the power, under TWICE the load. If you can increase load and maintain high voltage you will always produce more power. The object of the game is to have cells that at a "high load" will still remain at near full charge voltage. It is our opinion that when giving a lipo a C rating it must maintain a minimum usable voltage to qualify for that rating. (i.e.: if someone calls a pack a 35C pack then it should, at 35c, have at least a 3.4-3.6v average discharge voltage for each cell in the pack)






There aren't really any brands that supply discharge graphs to support their ratings. We used to do this, and are going to start doing it again. So when you go to buy your next packs, ask the supplier to supply you with discharge graphs. Have them prove their ratings.


We will guarantee, that our Elite packs will perform at our C ratings or your money back. We have the discharge graphs to prove our cells ratings.

Last edited by Chris_The_Battery_Man; 10-04-2010 at 03:02 PM.
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Old 10-04-2010, 03:12 PM   #2
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Great info Chris! This is why CBP gets my business. You back your packs cause you know they perform as you claim! Thanks for taking the time to post this!

Packs ordered!
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Old 10-04-2010, 03:17 PM   #3
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Ive been waiting for someone to do real world comparisons with lipo cells. You just earned a new customer next time I order packs.
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Old 10-04-2010, 03:23 PM   #4
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Quote:
Originally Posted by killswitch View Post
Ive been waiting for someone to do real world comparisons with lipo cells. You just earned a new customer next time I order packs.
Thanks for the kind words. Glad proof earned a customer over hype. Id rather die honest than rich
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Old 10-04-2010, 03:32 PM   #5
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Thanks for the kind words. Glad proof earned a customer over hype. Id rather die honest than rich
Its so hard to find legit info when it comes to lipos. I managed a LHS when the lipo craze hit and was building packs for my airplane customers from the get go and Ive bought a lot of packs since and only once have I been able to reproduce the manufacturer's claimed ratings with a GFX. Makes me miss the old days of racing matched sub Cs, although I always hated them when used on a crawler.
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Old 10-04-2010, 03:35 PM   #6
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Good info....I like tests like these with real world results....

Curious though, why blur out the other battery packs names? I sure would like to know who's packs are not up to snuff....

Later EddieO
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Old 10-04-2010, 03:38 PM   #7
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Quote:
Originally Posted by EddieO View Post
Good info....I like tests like these with real world results....

Curious though, why blur out the other battery packs names? I sure would like to know who's packs are not up to snuff....

Later EddieO
even while blured i can make out the logos... both of which i run
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Old 10-04-2010, 03:39 PM   #8
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Quote:
Originally Posted by EddieO View Post
Good info....I like tests like these with real world results....

Curious though, why blur out the other battery packs names? I sure would like to know who's packs are not up to snuff....

Later EddieO
We would like to maintain the peace. Don't wanna start any Sh!t. You're welcome to PM me, and I will gladly tell you. I would just ask you keep it to yourself. But to go public, would cause drama I don't want. Plus, one of the 2, is a vendor here. My run in's with them have been less than pleasant.
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Old 10-04-2010, 03:41 PM   #9
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Quote:
Originally Posted by robbio4422 View Post
even while blured i can make out the logos... both of which i run

Not everything is as it seems, or claimed. Remember that in the future. Weather you buy from me, or some other reputable brands. I just don't like seeing people paying for something they're not getting. That's like buying a Ferrari, with a motor that Kia made... Just not fair. I surely don't think everyone should buy from us, just that they get what they pay for, and that their purchases work best for them. Unfortunately that's not always the case.
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Old 10-04-2010, 03:52 PM   #10
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even while blured i can make out the logos...

yeah it isn't that hard to figure out. Thanks for the info, CBM.
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Old 10-04-2010, 03:52 PM   #11
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Very nice!
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Old 10-04-2010, 04:01 PM   #12
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Do you plan on testing any other brands? I wouldn't mind seeing how the Hyperion EX series stacks up.

Nice work.
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Old 10-04-2010, 04:10 PM   #13
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I purchased a couple of Elite packs a few years ago when I built an 1/8 RC8e. They were 4S 20C (this was well before C ratings of more than 20C was common) and if I remember correctly they were in the 4800 mAh range. They provided excellent power, ran cool, were well balanced, and were still running strong after innumerous cycles and hard use in the RC8.

Good to see they are still making quality packs.
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Old 10-04-2010, 04:14 PM   #14
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Originally Posted by dezfan View Post
I purchased a couple of Elite packs a few years ago when I built an 1/8 RC8e. They were 4S 20C (this was well before C ratings of more than 20C was common) and if I remember correctly they were in the 4800 mAh range. They provided excellent power, ran cool, were well balanced, and were still running strong after innumerous cycles and hard use in the RC8.

Good to see they are still making quality packs.

That's actually funny, because I made Mike stop carrying those, because to us, those were crap. Glad you're happy with em though.


ol' gravy leg:

You're not the first to have asked that. I may bring in some other brands to test.....
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Old 10-04-2010, 04:21 PM   #15
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They wern't as nice as my Polyquest packs, but they ran pretty good. By todays standards, they may not be all that, but in 2008 they ripped in my ebuggy.
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Old 10-04-2010, 04:41 PM   #16
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this is a perfect example of the highest level of customer service.....from people who actually give a crap about what their products are really being used for....not just to make a sale....

way to go guys keep up the great work.....

i will be buying from you from now on...
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Old 10-04-2010, 04:53 PM   #17
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Hmm, good to know.

Very interesting
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Old 10-04-2010, 06:01 PM   #18
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I started to read this post. But then I caught myself staring at your avatar in a trance and forgot all about it. I'm sure you probably have good info in here though.
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Old 10-04-2010, 06:21 PM   #19
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Great info illustrating that power isn't just about amps, it is about volts under load. Glad you guys have some solid manufacturers for your packs, and that you have the capability to test them out.


Did you consider retesting the p1 cell with the other cell harvested? Maybe you just had a bum cell?
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Old 10-04-2010, 06:34 PM   #20
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Quote:
Originally Posted by JohnRobHolmes View Post
Great info illustrating that power isn't just about amps, it is about volts under load. Glad you guys have some solid manufacturers for your packs, and that you have the capability to test them out.


Did you consider retesting the p1 cell with the other cell harvested? Maybe you just had a bum cell?

We actually thought the same thing, so we actually tested the whole pack, and cut the voltage in half. The fact that the cell had a somewhat normal curve @ a 10C load, was a sheer indicator that the cells were a low C rating and quality.
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