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Discussion Starter #1
two 2400 mah cells rated @ 40c packed inside a unit rated at 4900 mah and 50+C, wired in parallel.

Why did I take it apart????

I was testing the packs, pump them up to 4.22 @ 1 amp on T35BL before discharging. First seven times went fine, redid a pack as a control, I fell asleep at the computer. I took it off at 4.55v and puffed......but didn't burn the house down.

Yes, I'm a dumba$$ for that.

But I did always find it weird a 40C and 50C pack from same company tested identical @ 35 amps, now I know why.

XXX784283
3.7V/40C
2400mah
2009.07.07

I'll have pics later, camera is in the garage and it's snowing.
 

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Talentless Hack
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keep in mind your not going to see a difference in voltage, only the burst rate the battery can handle under load.

In the end however, your right. Your not going to see any difference until you pair it up with a lower wind motor. Cycling it on a charger won't tell you much.
 

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Discussion Starter #3
keep in mind your not going to see a difference in voltage, only the burst rate the battery can handle under load.

In the end however, your right. Your not going to see any difference until you pair it up with a lower wind motor. Cycling it on a charger won't tell you much.
But, I was not sold what was advertised. Seems a company just slapped a 50C sticker on a 40C pack.

I understand how big this is. The cells INSIDE are rated at 40C, but 50C sticker on the outside.

I'm not looking to have to pack replaced either. I paid $70 shipped for it and messed it up on MY account. But if I didn't mess it up, how many others have been dupped?

It would be like Ford selling you a 450 hp car, but it only puts out 375...wait, they got busted doing exactly that.
 

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Yea, I know what you mean... This is something we talked about when this "my C rating is better than yours" war started. It doesn't really suprise me, when you consider they dropped a 40c pack on us, only to make a 50c pack available less than a month later.
 

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That is what gets me. I have "Power Push" 5000 40c which is in same case as the above, 5300 mah with WAY better numbers.....if I could only drive :) There was a lap difference between the 4900 50C+ and 5000 40C pack, both in the same cases, likely from same company.

Battery wars is what knocked me out of RC racing 18 years ago when the 1700 SCR Blacks came out......and the Tekin 411 ESC's.........history repeats.

I ran the boxy Novak T1X for the longest time, 1/2 oz over weight, but was top three...way back then.
 

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Did you test them at 40C or 50C ?
Perhaps it is the 40C that is mislabeled and they are actuallly 50C.

One thing is sure, they are easier to test one at a time.
 

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Discussion Starter #7
When the label on the outside states 50C+ 4900mah, which I paid for, but both cells inside state 40C 2400 mah AND the hand written info on the flap also states 40C.

My other thread with pics......

http://www.hobbytalk.com/bbs1/showthread.php?t=276798

If needed I can have several WELL respected local racers confirm the info, four of them have national wins, two of them supply the tires we love, all four are members on this board.
 

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That is what gets me. I have "Power Push" 5000 40c which is in same case as the above, 5300 mah with WAY better numbers.....if I could only drive :) There was a lap difference between the 4900 50C+ and 5000 40C pack, both in the same cases, likely from same company.

Battery wars is what knocked me out of RC racing 18 years ago when the 1700 SCR Blacks came out......and the Tekin 411 ESC's.........history repeats.

I ran the boxy Novak T1X for the longest time, 1/2 oz over weight, but was top three...way back then.

Wasnt 411p that OWNED you... It was Tekin 410K..
 

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As you found out, labels can say anything. Maybe the 2400mAh 40C labels are wrong and they would actually test higher. Unless you actually test against the numbers you were sold, you don't know. Back in the NiMh days, it was not uncommon for for cells labeled as, for example, 4000mAh to actually have more then that.
 

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Discussion Starter #13
It would be smarter if he didn't charge a LiPo on a NiMH setting.
I have Lipo chargers, was charging on the TP-1010 @ 10 amps, then topping off on the TC35BL @ 1 amp.....only I fell asleep at the desk waiting on the last one.

$70 error that could have been 2000 times worse.
 

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I have Lipo chargers, was charging on the TP-1010 @ 10 amps, then topping off on the TC35BL @ 1 amp.....only I fell asleep at the desk waiting on the last one.

$70 error that could have been 2000 times worse.
But in the end, you were still charging a LiPo on a NiMH charger setting. Otherwise it wouldn't have gotton to 4.55V
 
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