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Old 08-25-2007, 06:31 PM   #31
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Originally Posted by bxpitbull View Post
You do realize Kokam cells are Korean? Not the much of a difference in stuff coming from Asia. Can you say Hyundai, Kia...DAEWOO
I highly recommend you look up posts/ask questions directly of linger. He knows the factories, procedures, and qualities of cells available.

External problems and user errors have NOTHING to do with internal cell faults that are more likely in certain cells than others.

Oh and let me know when you find those American made cells. Wait you mean there aren't any? Crap.
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Old 08-25-2007, 07:35 PM   #32
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I highly recommend you look up posts/ask questions directly of linger. He knows the factories, procedures, and qualities of cells available.

External problems and user errors have NOTHING to do with internal cell faults that are more likely in certain cells than others.

Oh and let me know when you find those American made cells. Wait you mean there aren't any? Crap.
Kuzo, you are about a day late and a dollar short. I made mention of the Kokam cells being made in Korea only because of the amount of times people talk about chinese cells. Thats it. And for the errors, look at how many people mentioned shorts and how Orions packs save their electronics....thats what you need to make mention of. Stop coming in on the tail end of a conversation critiqueing.....and stay out of my crosshairs.
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Old 08-25-2007, 07:39 PM   #33
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Ummmyeah..."check for shorts".

I raise a significant safety advantage of the Orion packs and you start building a straw man. Nice one. I see why you have to constantly threaten people...LOL
Advantage being that you didnt safety check your gear before plugging your pack to your ESC??? Tsk tsk. I dont have to threaten people, I just call it as I see it. You dummies make it seem like I dont like Orion. I think they are excellent cells, I prefer the Mah selection of Maxamps. If I decide I want more than 4800, well, Orion is shit out of luck huh? The case, makes it safer, the internal fuse is great for you forgetful ones but you know what, I have yet to short out anything. So I ask again, out of all the people that have bought Maxamps packs, where are the horror stories???????
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Old 08-25-2007, 07:46 PM   #34
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Isn't this about the first time I've ever actually said anything directly to you in disagreement? Don't worry, you won't hurt my feelings if you attempt to take me to task though.

A little less than a day though, I'll agree to 24 minutes. You mentioned Korea, China same difference 24 minutes before I posted. I simply pointed out you were so very wrong in my opinion and gave you resources that may assist in correcting your misconception regarding lipo manufacturing qualities.

Crosshairs? WTF have you been drinking tonight? Jack Daniels here.
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Old 08-25-2007, 07:52 PM   #35
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Uhhh...no...it was running just fine and had been. The ESC shorted while it was running and it went "nuclear".

The battery saved the car from burning to the ground on the other side of the track. It singed the chassis, bubbled-out the body and melted the reciever case...then the battery fuse blew, it stopped cold and cooled off. I don't know of another battery that will do that.

The pack wasn't puffed and it could have probably been salvaged and I bet it would then have been at least as good as a soft Lipo... I lost a pack, but I didn't have to buy a chassis.

You run what you want, just be fair and accurate when you're comparing batteries.

You may now resume the name-calling, otherwise rude and boorish behavior that you apparently take such pride in.

Quote:
Originally Posted by bxpitbull View Post
Advantage being that you didnt safety check your gear before plugging your pack to your ESC??? Tsk tsk. I dont have to threaten people, I just call it as I see it. You dummies make it seem like I dont like Orion. I think they are excellent cells, I prefer the Mah selection of Maxamps. If I decide I want more than 4800, well, Orion is shit out of luck huh? The case, makes it safer, the internal fuse is great for you forgetful ones but you know what, I have yet to short out anything. So I ask again, out of all the people that have bought Maxamps packs, where are the horror stories???????
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Old 08-25-2007, 08:03 PM   #36
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Because I know very few people ever bother to do a search, I found this for you. From the Orion 3200 thread a serious look into Chinese cell quality. This is from a series of posts from linger - someone who actually knows the lipo industry. I hope he doesn't mind my reposting of this info; when he is back on the board he is free to tell me to remove. This is probably the best look into the differences in lipo quality you can get and the reasons why.

Quote:
QUALITY CONTROL:
Quality control is a joke in most China factories. Incoming material inspection, statistical process control, in-process measurements, Hi-Pot testing, six sigma etc are completely foreign concepts. In a lipo cell, the main source of failure is from internal shorts. In most cases, an internal short burns off a little material, creates a little gas, and you have a puffy cell with less capacity. Othertimes, the short can melt enough of the separator which causes shorts in other areas of the cell and the chain reaction causes a flame situation. These shorts may be prevented in manufacturing with good control over contaminants and manufacturing burrs. All the top tier manufacturers will have automated Hi-Pot testing where a large voltage is applied (200-300 volts) before the electrolyte is applied and the resultant current is measured - high current means that something is shorted out. The China factories don’t do this. The top tier factories will have specialized equipment to transfer material without exposing it to the environment thus reducing contaminants. The China factories literally use cooking pots and scoop them out manually. I could write a whole book about what the China manufacturers do wrong with respect to quality control, like how they measure coating thickness on a moving roll with a micrometer!!!, but I won’t bore you guys with that.
When asked about their failure rate after manufacturing – the China sales rep was proud to say that 0.3% of their cells swell up just sitting on a rack after manufacturing due to internal shorting – who knows how many cells are close to shorting out internally. Out of only 1 million cells – that’s 3000 failures. I asked a top tier manufacturer the same question – they produce 4 million cells a month – in 1 year, or 48 million cells later – they had a total of 0 cells swell up by themselves after manufacturing. 3000 cells out of 1 mil failure or 0 cells out of 48 million cells failure – that’s what you are paying for.

PERFORMANCE:

Current Rating – Most of the top tier manufacturers are fairly close to their published current rating. I find that most all the manufacturers are a little optimistic in their C-rating. Some of the China cells do live up to their C-rating, but I’ve tested some 20C rated cells from China that are virtually destroyed at a modest 10C discharge rate. Basically, there is no guarantee that a 20C cell from China can really do 20C. Some of the cells from China actually can do 20C and they hold a higher voltage than the top tier manufacturers - due to more volatile cathode chemistry, but at the expense of safety (see the safety section).

Cycle Life – the cycle life of the top tier manufacturers is stunning. I’ve tested many cells that perform just as good on their 400th cycle as they did their first. For whatever reason – every China cell has a degrading profile, where the capacity drops slightly every cycle. The rate of degradation varies depending on manufacturer. Some don’t last 100 cycles, while others are about 80% capacity at 300 cycles. The bottom line is that the cycle life is virtually guaranteed with a top tier manufacturer and it’s a crapshoot when you buy a cheap cell.

SAFETY:

The first step in safety is a top quality cell construction (see quality control). The elimination of contaminants and internal shorts is good prevention. I’ve tested enough cells to know that there is not a single Lipo cell on the market that can take an extreme overcharge condition without going up in flames. The distributors that show a little video about how the cells “can’t” be ignited through overcharging are sending the wrong message. Give the cell to me, I guarantee you that I can ignite it (except for the A123 Li-Ion cell). The next step in safety is the cell design itself. Most of the China cells use pure LiCo2 coating on the cathode which is the most volatile and also the most powerful molecule. That way, they have a great looking discharge curve for the first few cycles. Most of the top tier cells will have other additives that greatly reduce the volatility and also suppresses voltage slightly. This means that the cell can take a higher temperature before it reaches thermal runaway, and even if it does reach thermal runaway, the resultant flame is much less. I’ve purposely overcharged and ignited China Lipo’s and all of them turn into immense flamethrowers that burn for about 30 seconds. When I purposely ignited a Kokam cell, it’s chemistry self extinguished in about 2 seconds – the flame was an order of magnitude less than it’s China counterpart. Furthermore, the Kokam cells use the negative tab as a built in overcurrent fuse. If you short out the cell, the negative tab vaporizes and creates an open circuit.

I have yet to visit a “top tier” manufacturer in China, though I admit, I haven’t visited all of them, but I’ve visited enough to understand their pardigm. However, these Chinese factories are evolving at an accelerated pace. These low quality factories may equal the quality of top tier manufacturers in just a few years, but they definitely aren’t there yet. Just about every China factory I visited was in the process of building another newer, better factory. I’ve referenced Kokam as a top tier lipo manufacturer. There definitely are more top tier lipo manufacturers and some even have superior manufacturing quality vs Kokam, but their pricing is the same as Kokam – which is nearly 4x more than their equivalent China counterpart. The top tier manufacturers admit that the RC market rates price over quality and it’s obvious that the low price lipos are now dominating the RC marketplace. The good news is that some of these top tier lipo manufacturers are currently teaming up with top tier RC manufacturers to come out with high quality and high performance packs though I guarantee you that they won’t be able to touch MaxAmps pricing.

So there you have it. Other than the hard case – this is why the Peak/Team Orion Lipo is so much more expensive than their competitors.
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Old 08-25-2007, 10:24 PM   #37
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The sound of people breathing through their mouths in this thread is deafening. It's like a damn wind tunnel.
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Old 08-26-2007, 01:42 AM   #38
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Turbo, welcome to the world of the pitbull. I talk trash, slander and otherwise, dis to keep the conversation going. I could care less what you or anyone else runs, I do it to keep ish going. You read waaayyy to far into it, and trust me, it wasnt that serious. We all develop brand loyalties and its obvious, you have yours...cool. Dont take anything I say serious...unless you ask for it directly.

Kuzo, you definately read waaayy to far into it. Quoting stuff from websites and all that crap, unnecessary. Dude asked about his cells and I plainly stated what he could have gotten for the same price with more Mah. All this chatter about orion this and fuses that, irrelevant. Maxamps works for me (and many other folks) and if orion is doing the job for you, play on playa. Now, to all of you dudes, time to let it go. This is getting stale.
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Old 08-26-2007, 02:14 AM   #39
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This is getting stale.
So is the bully act.
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Old 08-26-2007, 02:32 AM   #40
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So is the bully act.
Well DUH. And it isnt an act...I'm an arrogant prick..and damn proud!
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Old 08-26-2007, 05:12 AM   #41
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Well DUH. And it isnt an act...I'm an arrogant prick..and damn proud!
I bet you are "proud" of whatever. It's still getting old.
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Old 08-26-2007, 08:48 AM   #42
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Kuzo, you definately read waaayy to far into it. Quoting stuff from websites and all that crap, unnecessary. Dude asked about his cells and I plainly stated what he could have gotten for the same price with more Mah. All this chatter about orion this and fuses that, irrelevant. Maxamps works for me (and many other folks) and if orion is doing the job for you, play on playa. Now, to all of you dudes, time to let it go. This is getting stale.
Don't worry, that post wasn't for you. There are other people in this thread besides you and me. It would be a failed effort to try to convince you to change your mind about anything am I right?
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Old 08-26-2007, 12:43 PM   #43
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Originally Posted by bxpitbull View Post
Turbo, welcome to the world of the pitbull. I talk trash, slander and otherwise, dis to keep the conversation going. I could care less what you or anyone else runs, I do it to keep ish going. You read waaayyy to far into it, and trust me, it wasnt that serious. We all develop brand loyalties and its obvious, you have yours...cool. Dont take anything I say serious...unless you ask for it directly.

Kuzo, you definately read waaayy to far into it. Quoting stuff from websites and all that crap, unnecessary. Dude asked about his cells and I plainly stated what he could have gotten for the same price with more Mah. All this chatter about orion this and fuses that, irrelevant. Maxamps works for me (and many other folks) and if orion is doing the job for you, play on playa. Now, to all of you dudes, time to let it go. This is getting stale.
Translation: Git 'er done.
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Old 08-26-2007, 12:52 PM   #44
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If a fuse is so important, fit one externally. By the sounds of it the fuse in the Orion pack doesn't work all that well if you car still melts lol.

I'm in the same boat as pitbull. I have nothing but praise for kokam cells performance, but not their price...

All the bike racers were banging on about how kokam are so much better than everything else, and using anything else is dangerous. Now half of them use enerland cell'ed packs, cause they realize they are still good quality and much cheaper.

I like enerland cells, but my most pleasant lipo experience so far has been with a 6000mah maxamps pack. I leave it in my car, race then put it straight back on charge and use it in the next one. Been doing this for quite a while and no sign of performance loss. I've been using a novak 5.5 sintered, and pack is just slightly warm after a race. I tried to race against gas cars once but only lasted 15 mins haha.
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Old 08-26-2007, 12:54 PM   #45
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Don't worry, that post wasn't for you. There are other people in this thread besides you and me. It would be a failed effort to try to convince you to change your mind about anything am I right?
What excatly do you want to change his mind about?

Do you want him to suddenly believe that the maxamp pack he is very happy with is shit because you told him so? lol
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