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C-rating for boats question

C-rating for boats question

Old 06-18-2014, 02:12 PM
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Default C-rating for boats question

The Mrs. bought me a ShockWave 26 V3 BL RTR, so far i'm very happy with it being my first boat. At first i getting used to it i ran my 2s race packs, that got boring fairly quickly. My local hobby shop had a battery sale so i picked up a Duratrax 3s 25c 5000, a week later i snagged a couple of used 3s 30c 5000 Tenergy packs from a fellow racer. I hadn't ran it for a week or so and noticed the new Duratrax pack puffed, not horribly bad but noticeable. So here's my question, all 3 packs get warm, not hot. I always balance charge and storage charge after the packs are cool before storing, is it pulling that many amps to puff that pack? Is 5c really that much of a difference in a boat? Or did i just end up with a bad pack? I would have just posted this in the boat section but there really isn't that much activity there. Thanks
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Old 06-18-2014, 08:22 PM
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Boats pull lots of power so the higher the c rating the better. I tried some 25 c's in my stilleto at first and first run they puffed a litttle. From what I can tell c ratings are not all that accurate. I ran some zippy 25c batts in the same boat and had no issues at all.
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Old 06-19-2014, 02:25 AM
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Originally Posted by hotrod87
Boats pull lots of power so the higher the c rating the better. I tried some 25 c's in my stilleto at first and first run they puffed a litttle. From what I can tell c ratings are not all that accurate. I ran some zippy 25c batts in the same boat and had no issues at all.
C ratings aren't accurate all the time, but it's a guideline.
A battery is a chemical process so it won't be the same every time and experiences may differ with the same product.

For boats you're indeed better of taking higher C values, 45C batteries would sure do the job. It's more expensive to replaced puffed batteries than to invest a bit more in better batteries beforehand.

Please be careful with puffed LiPo's, you'd think it won't happen, but they do really explode..
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Old 06-19-2014, 04:56 AM
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C-ratings are voodoo and not all are equal of course. But environmental factors can even come into play like a cool vs warm lipo.

As a rule though, the higher C-rating you can afford from your brand of choice the better off you will be.
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Old 06-19-2014, 06:02 AM
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I kinda had a feeling it was the pack only being 25c but at the time it was cheap. The weird thing is if you look at the Traxxas Spartan, Traxxas actually suggests using their 25c packs and i know from my buddies boat it draws way more amps than mine.
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Old 06-19-2014, 07:27 AM
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Originally Posted by Thaan
Please be careful with puffed LiPo's, you'd think it won't happen, but they do really explode..
Lipo's don't explode, they just catch fire if you screw up...and screw up bad. nimh batteries explode!! P.S. puffed lipo's = trash can
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Old 06-19-2014, 01:17 PM
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Originally Posted by Johnnysplits
Lipo's don't explode, they just catch fire if you screw up...and screw up bad. nimh batteries explode!! P.S. puffed lipo's = trash can
They do, we had a visitor racing his F1, and his LiPo catched fire and exploded within seconds.
His entire F1 burned down and he had 3rd degree burns, simply because he held it for 2 seconds before he dropped it.
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Old 06-19-2014, 03:20 PM
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Originally Posted by Thaan
They do, we had a visitor racing his F1, and his LiPo catched fire and exploded within seconds.
His entire F1 burned down and he had 3rd degree burns, simply because he held it for 2 seconds before he dropped it.
WOW!! That's a first I've heard of a lipo exploding.
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Old 06-20-2014, 07:16 PM
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Somewhat semantics I suspect. Going by the most literal definition I don't think lipos actually explode like a nimh can. But if you've ever seen a lipo go off, they can very quickly throw off quite intense flame and lots of nasty toxic smoke, it's very easy to relate it to an explosion. And yes burn up a car and anything in the general area.


+ on boats needing really good batteries, boats are typically a high nearly constant load. Suggest being especially careful with run time / ending voltage, as lipos tend to heat up more as they approach discharged when under a high constant load.
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Old 06-21-2014, 07:44 AM
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Well again i appreciate the input guys, I'll be sure to get higher C-rated packs on the next battery order i make.
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