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Thread: SPC Lipo's

  1. #1
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    SPC Lipo's

    Thought I'd get some advice from you guys!!!! I had 2 batteries take a dump today, and I need to replace them. I got 2 SPC 6500mah 50C 2s a couple weeks ago and I'm really impress'd!!! My question, is it worth step'n up to the 55c/65c packs or should I stick with the 50c packs and save a lil $$$??? I do race (and so does my 14yo son) and that's pretty much where they will get used. Appreciate any advice!!!!!!


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    Last edited by ksb51rl; 01-28-2013 at 12:51 AM. Reason: Content
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    It would only improve charge time, you can charge at a higher amp rate with what you have in mind. This will help you with charge time at the track, although you probably have more than one pack if you race.
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    I've owned both the SPC 50C and 65 C and you will notice a difference in the punch. You really can go wrong with either pack. What kind of esc and motor are you using??

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  5. #5
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    Can someone show me the spc sight where I can get a spc lipo?

  6. #6
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    Quote Originally Posted by Bash'n'slash View Post
    Can someone show me the spc sight where I can get a spc lipo?
    SPC RACING
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  7. #7
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    Quote Originally Posted by Dgb007 View Post
    It would only improve charge time, you can charge at a higher amp rate with what you have in mind. This will help you with charge time at the track, although you probably have more than one pack if you race.
    not true, the c rating has nothing to do with charge time. that is to be specified by the manufacturer of the pack. charging at anything over 1c is not good for the battery and will decrease its life.

    going higher than 50c with a 6500mah pack is a waste of money, in fact, you could go less. your packs are good for over 300amps and not many motors will pull that much. so id stay with the 50c range and you will never have a problem with amp draw.

  8. #8
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    I got 4 of there 3S soft packs and love em. Just a basher here.

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    Quote Originally Posted by WJ Jeep Guy View Post
    not true, the c rating has nothing to do with charge time. that is to be specified by the manufacturer of the pack. charging at anything over 1c is not good for the battery and will decrease its life.

    going higher than 50c with a 6500mah pack is a waste of money, in fact, you could go less. your packs are good for over 300amps and not many motors will pull that much. so id stay with the 50c range and you will never have a problem with amp draw.
    Well yes and no. The C rating for charge and discharge are usually directly proportional, some manufacturers will issue a lower charge rate. Charging above 1C for a pack that is rated for it will not decrease its life. The issue with charging too high is increased risk of exploding the pack. I usually charge at 2C and when Im in a hurry to get packs recharged I charge up to 4C on packs rated for 5C charge rate. I will agree that extremely high C rated batteries are simply marketing fluff. You simply need to figure out your load and find what you need from there.

    Slash 4x4=1200watts max load (average is around 1000watts)
    If you want to run 2s 5000mAh
    1200/7.4=162amps
    5000mAh=5amps
    162/5=32.4C
    32.4x1.4=45.36C peak
    So anything over 50C is a waste of money as you will never use it.

  10. #10
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    Once my tax refund clears, I am getting some. Heard so much good stuff about them.
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  11. #11
    RC Turnbuckle Jr. rag6's Avatar
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    I would like to see if jakey can clear some of this up...

    He told me in that even in a 17.5 stock class, an accurately rated boosted c-rating (that will go way above and beyond the amps that the motor can pull) will have a benefit in competitive racing. This goes against a statement above that says anything over this c rating will be wasted with a particular motor.

    I was thinking that my there would be no benefit to running my 50c's over my 25c's in a 17.5 stock class. I was told that it would be important to run the 50c's for a performance boost.
    Last edited by rag6; 01-29-2013 at 03:22 PM.
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    Quote Originally Posted by rag6 View Post
    I would like to see if jakey can clear some of this up...

    He told me in that even in a 17.5 stock class, an accurately rated boosted c-rating (that will go way above and beyond the amps that the motor can pull) will have a benefit in competitive racing. This goes against a statement above that says anything over this c rating will be wasted with a particular motor.

    I was thinking that my there would be no benefit to running my 50c's over my 25c's in a 17.5 stock class. I was told that it would be important to run the 50c's for a performance boost.
    well to a point it does matter. a 25c over a 50c is going to make a difference. but going from a 350 amp pack to a 400 amp pack will not make a difference. these motors are using such a small percentage of the packs rating its not going to make any noticeable gains.

    he was looking at going from a 6500 50c (325 amps) to a 6500 65c (422 amps) and thats not going to do anything. ive ran 65c and 50c in pan cars, sc trucks, buggies, and savage flux's, and in most of them the 65c was actually slower, at that point it came down to the quality of cells not the c rating. and both were very high quality packs. in the savage we could tell the difference but thats a little bit different situation than these smaller trucks.

    so my recommendation is to save the $20 a pack and get the 6500 50c because your wasting money on something you wont benefit from.

  13. #13
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    Let me put it in a simpler term.
    Regardless of if you run a 120 volt 1600 watt hair dryer on a 20 amp or a 200 amp breaker its going to draw 13.33 amps. Power is certain as are the mathematical calculations for it. Watts will always=VxA.

    Same applies for DC motors, Watts=VxA
    A 1200 watt motor load @ 7.4 volts will pull 162amps continous with a set peak crest factor of 1.4 regardless of it pulling from a 300 amp pack or a 500 amp pack.

    I=V/R is a constant of electrical propagation that will never change, it is what it is. Cant change Ohms law.

    The above mentioned is like saying that if you put a 1200 CCA battery in a car whose starter only pulls 500 CCA that it will make your car start faster, just isnt happening.

    Yes there is a difference when you are talking abour 25C vs 50C. In a 5000mAh pack 25C is under rated for the load and 50C is not.

    The only thing you really have to worry about outside of the constants of the calcualtions is if the brand of battery you have chosen has provided an accurate C rating. If your calculation said 40C and you put a 50C pack in and it caused the ESC to undercurrent someone was lying and it wasnt the calculation.
    Last edited by JustinThyme; 01-29-2013 at 05:58 PM.

  14. #14
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    Quote Originally Posted by JustinThyme View Post
    Let me put it in a simpler term.
    Regardless of if you run a 120 volt 1600 watt hair dryer on a 20 amp or a 200 amp breaker its going to draw 13.33 amps. Power is certain as are the mathematical calculations for it. Watts will always=VxA.

    Same applies for DC motors, Watts=VxA
    A 1200 watt motor load @ 7.4 volts will pull 162amps continous with a set peak crest factor of 1.4 regardless of it pulling from a 300 amp pack or a 500 amp pack.

    I=V/R is a constant of electrical propagation that will never change, it is what it is. Cant change Ohms law.

    The above mentioned is like saying that if you put a 1200 CCA battery in a car whose starter only pulls 500 CCA that it will make your car start faster, just isnt happening.

    Yes there is a difference when you are talking abour 25C vs 50C. In a 5000mAh pack 25C is under rated for the load and 50C is not.

    The only thing you really have to worry about outside of the constants of the calcualtions is if the brand of battery you have chosen has provided an accurate C rating. If your calculation said 40C and you put a 50C pack in and it caused the ESC to undercurrent someone was lying and it wasnt the calculation.
    True, but not correct. you have all of the math right and all of the laws, but.....the higher the rating of a pack, the better it will hold voltage under load. so yes the basic theory that getting a battery that is rated for what you need, is all you need, is correct in theory. however voltage sources dont only work on the fact that they can provide just enough power. for example, in your house when the fridge or air conditioning kicks on there is a voltage drop and the lights slightly dim, thats normal. but if you live in a much older home with older wiring, and that kicks on most often everything flashes or almost turns off. thats just like the c rating with batteries. the 25c pack being the older home, and the 50c being the newer home. they both work, but the newer home handles it better.

    its also much easier to just put everything into amps. most people are running 2s packs so the 100 amp rule is correct for the vxl or similar motors. watts just isnt necessary and batteries are more or less rated in amps, so why make it more complicated than it has to be. also, if you do watts you have to account for the drop in voltage as the pack runs down. so at the start at 8v its different than when its at 7.6v, so thats a changing "constant", and you dont want to use that at all.

    so a 5000 25c battery is perfectly fine for a vxl motor. it wont puff or do anything, but the voltage will drop more under load than a 50c battery. however you do get to a point where upping the c rating wont make the voltage drop significant enough to make it worth the money.

    also, putting a 500cca battery in a car that pulls 500cca is not a good idea. it wont start very well. in fact it probably wont start in the winter at all. my car "requires" around 800cca but i have a 1100cca battery in it. and it starts a lot better than when i had a 1000cca battery in it.
    Last edited by WJ Jeep Guy; 01-29-2013 at 11:07 PM.

  15. #15
    RC Turnbuckle Jr. mike-susieq1's Avatar
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    I have to agree get some spc lipos and you can't go wrong there. I plan to get some more after my icharger first for my maxx at least. I want the 65c going for 40 right now I think work it for sure I need the amps here!
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  16. #16
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    If the C rating on packs are accurate or at the very least relative to each other, then the pack with the higher C and corresponding lower IR will allow the motor to make more power due to the pack holding higher voltage under a given load. This is with all other things being equal.
    Within reason this will hold true regardless of the RC motor used, whether it be a 17.5 turn stock-type or low turn mod. The often repeated comment that there is no reason to go over a certain C range because the motor Amp load does not exceed the calculated C potential, is just a myth.

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