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Old 03-13-2008, 05:22 AM   #16
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Okay. I have a question. I am a controls electrician, and these wire guage sizes frighten me.

If I am understanding this correctly, these lipo packs can deliver up to 150A of current? The last time I checked, 150A using high temp wire like silicone, needed #1AWG wire. How are they using anything less without melting the casing?

Even 40A should use #10awg high temp wire..... I know that once I get back into the swing of things with this new technology, I will be asked by my friends how this is possible, and I really want to understand this so I can give them a reasonable response....
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Old 03-13-2008, 06:16 AM   #17
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Originally Posted by Zagar View Post
Okay. I have a question. I am a controls electrician, and these wire guage sizes frighten me.

If I am understanding this correctly, these lipo packs can deliver up to 150A of current? The last time I checked, 150A using high temp wire like silicone, needed #1AWG wire. How are they using anything less without melting the casing?

Even 40A should use #10awg high temp wire..... I know that once I get back into the swing of things with this new technology, I will be asked by my friends how this is possible, and I really want to understand this so I can give them a reasonable response....
Can a battery pack have a Peak current at 150 Amps or more – yes it is possible. I’m not sure of the method of the peak current measurement the manufacturer was using. Normally you should never see the motor peak at 150Amps during the race, the peak should occurred only from stop and go it called inrush current (instantaneous current drawn by the motor). Unless you hit things all the time during the race then your motor may peak more then one.

Be able to sustain higher continuous current is what make the battery pack shine.

#12-16 AWG should be adequate for what we are doing. If I am not mistaken the measurement (Resistance, Max current, voltage drop, wire temperature and so on) were calculated at 1000 feet. Conductor size and material, Insulator size and material is matter at a 1000 feet. But a few inches here and there on our RC car I wouldn’t bring out my slide rule and a note book just for that.
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Old 03-13-2008, 06:24 AM   #18
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That's a good point komkit.... I forget that the NEC measures over long distance, not merely a few inches. Even still...

Does this mean that the 150A rating is an FLA type of rating? I wasn't aware that that was what they were referring to...

After initial inrush, what is the typical sustained current draw of these ESC's and motors on the tracks? Both off-road and on-road?

Thanks for the info!
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Old 03-13-2008, 07:57 AM   #19
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the real bug is not in C rating but who will buy 1000 pack and more at 25C when 1 month later the 35C is spirit to leave and your 25C cell is out of date

for 4 months later the pack more hot pack had 20C and now I see 33C in production soon

And for the price The lipo is not very good +- 100 cycle for racing and +- 200 for bashing very low lifecycle

Ok yes it was very powerfull and light

But when i test lifepo4 cell at 20C rate and 2C charge and after 100 cycle the capacity is same and more i think change for it soon


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Old 03-13-2008, 08:10 AM   #20
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I'm not entirely sure of which Lipo's your using but realistically if taken care of the cycle life in into the 300's which is well worth the money.

It's when the cells are abused that your cycle life drops to 100 or so

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the real bug is not in C rating but who will buy 1000 pack and more at 25C when 1 month later the 35C is spirit to leave and your 25C cell is out of date

for 4 months later the pack more hot pack had 20C and now I see 33C in production soon

And for the price The lipo is not very good +- 100 cycle for racing and +- 200 for bashing very low lifecycle

Ok yes it was very powerfull and light

But when i test lifepo4 cell at 20C rate and 2C charge and after 100 cycle the capacity is same and more i think change for it soon


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Old 03-13-2008, 09:00 AM   #21
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Remember I think in this case that this bench spec racing is somewhat irrelevent. As noted by others this performance is beyond how we are actually using these things. Which is exactly opposite of back in the day.
Danny, how do you know that the packs are being tested this way? Seems a little surprising to me, isn't the company name Superior Matching Concepts, not Superior Manufacturer Commision? Which if represented properly can be a legitimate biz model. But as an established industry player, you are claiming the best numbers, and you apparently aren't verifying the manufactures claims? I may be off base here, my apologies if so, feel free to call me out, but how is what you have offered so far different from all the other resellers jumping in? That seems to be at least one point of the thread to me.
I don't think what we offer is so different from what some others offer. We have seen some very good packs during our testing of other brands. We are being as forthcoming as we can in an attempt to learn and understand what constitutes a good, quality lipo pack. We have nothing to hide.
What is wrong with cycling the packs on a GFX and printing the numbers on the package? I don't see anyone else volunteering to do it. I know that it is a far cry from the high amp loads used to determine C ratings, but it is a start. At least it is a way to quantify performance that racers are already used to and understand.
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Old 03-13-2008, 09:15 AM   #22
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Originally Posted by Zagar View Post
Okay. I have a question. I am a controls electrician, and these wire guage sizes frighten me.

If I am understanding this correctly, these lipo packs can deliver up to 150A of current? The last time I checked, 150A using high temp wire like silicone, needed #1AWG wire. How are they using anything less without melting the casing?

Even 40A should use #10awg high temp wire..... I know that once I get back into the swing of things with this new technology, I will be asked by my friends how this is possible, and I really want to understand this so I can give them a reasonable response....
The C rate is checked direct from the lipo cell, not through the wire.
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Old 03-13-2008, 09:24 AM   #23
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Originally Posted by Jack Rimer View Post
The C rate is checked direct from the lipo cell, not through the wire.
Okay, I understand that. In controls wiring, you size the wire for the delivery. If you have a 200A feed, and a 100A breaker for example, you have to size the wire to cover that 200A feed.

If lipos are capable of delivering 150A at FLA, how is it that the wires won't melt in the rare occurance of a malfunction of some sort?

I don't mean to be thick about this, but I am trying to understand. As I asked before, after the initial inrush, what is the typical sustained current draw of these lipo-based ESC's and motors on the tracks, both off-road and on-road, that don't require a more substantial wire?

Is the 150A rating a showoff number? Am I looking at this incorrectly? This is interesting to me, and hopefully to others that want to understand the rating and wire sizing of these packs.
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Old 03-13-2008, 09:51 AM   #24
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I'm no expert when it comes to wire sizes and it's limits but I can tell you that a higher C rate pack performs better than a lower C rate pack. I believe this is due to the higher C rate having lower IR and higher average voltage. Lower IR means less voltage drop under load.

A long time ago I mentioned on this message board that Lipos would not be the perfect solution like some want it to be. I was basically told that I didn't know what I was talking about and all I wanted to do was keep my matching business alive.

Here is what we have since proved about Lipos. Not all Lipos are the same and some do offer more performance than others. Lipos are improving by increasing the C rate which makes for better performing packs. To fully extract the most performance out of your Lipos youi need to warm/heat them up prior to using them.

This is a learning process but some of the so called benefits of Lipos that were originally stated aren't that accurate when you start using Lipos in high end racing.
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Old 03-13-2008, 10:01 AM   #25
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...what I find interesting is that with 'Sub c' cells (NiMh or the old NiCad), we were only allowed to use certain 'approved' cells. These cells had to be of certain size and mah ratings.

With LIPO it seems nobody wants to use a similar criteria...and they are just trying to DUMP something "Better than the other guy" on the market

IF the market were capped to a 3200 mah or a 5000 mah or what ever cap was agreed upon, and a MAX 'c' rating as well, I think you'd find a lot more of these batteries would be a lot closer in thier performance.

I can also tell you that while at the "ULTRA WORLDS" type of events LIPO may not be the answer ...at the local CLUB LEVEL and the Regional Level events - LIPO RACING is AWESOME! (Especially where the rules are VERY TIGHT)
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Old 03-13-2008, 10:06 AM   #26
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The ROAR rules do have a size limit which will keep things under control. There is no way to control a Lipo manufacturer from imrpoving his blending formula , buying better materials and finding better ways to make there Lipos.

Lipos aren't different than sub-c cells as they will get better overtime. What we may see is improvements coming out faster than sub-c as there is more manufacturers making Lipos.
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Old 03-13-2008, 10:53 AM   #27
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Our Lipo manufacturer has informed me that the common industry standard used for C rate is for the capacity to stay at 90% under a full C rate discharge down to 2.8v per cell. The cell needs to hold up for 50 cycles at 90% of its capacity.


Not all companies use this standard and this explains why we have sent some packs from different manufacturers for C rate testing and some of them were not at the advertised C rate.

For anyone doubting our C rate feel free to buy a pack and have it sent to the proper lab for tetsing. You will see we have nothing to hide and our packs are what they are advertised to be.
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Old 03-13-2008, 10:59 AM   #28
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Matchers messed with the "standard" matching process of the CE Turbomatcher and advertised bogus numbers with Nicd/Nimh, its no different with lipo. Eventually racers will try all the different packs and the word will spread of which lipo's are good and which ones are bad. The situation isn't really any bigger of a deal then before. It will work itself out.
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Old 03-13-2008, 11:26 AM   #29
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Quote:
Originally Posted by Zagar View Post
Okay. I have a question. I am a controls electrician, and these wire guage sizes frighten me.

If I am understanding this correctly, these lipo packs can deliver up to 150A of current? The last time I checked, 150A using high temp wire like silicone, needed #1AWG wire. How are they using anything less without melting the casing?

Even 40A should use #10awg high temp wire..... I know that once I get back into the swing of things with this new technology, I will be asked by my friends how this is possible, and I really want to understand this so I can give them a reasonable response....
let me say up front, i have no idea how most of this works, but just thinking out loud, i'm gonna assume that when these load tests are being done, they are not using the deans plug that comes on the pack, there fore i am also gonna assume that they are not using the wire the deans plug is soldered to. i would imagine that it is a direct connect test.

i imagine someone a lot smart then most of us, will sit down, and take how each battery company is getting their numbers, and tell us how they actually compare, using non cycled batteries, (cause i ain't gonna cycle my batteries 6 times before every heat and main), non heated batteries (cause that also fudges the numbers) just a straight up side by side test.

battery numbers have always be fudged, and the apparently always will be.
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Old 03-13-2008, 11:31 AM   #30
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Default Useless C scores

C rating means nothing to me.

I already know the "battery matcher`s" will always claim higher C number`s than other battery`s available, no matter what ....
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