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  1. #1
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    ? about C rating for charging

    Hi all i was wondering if you guys can explain to me how 5C's would relate to how high amperage wise you can charge that battery at.

    For example if you could charge it at 5C what would that translate to amperage wise.

  2. #2
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    it depends on the size of the pack
    a 5000mah pack charged at a 5c rating would be 25amps
    and you need a big charger to charge at that rating..
    most lipos can be charged at a greater rate than 1C
    2-3C is possible with most lipos
    but most do no know this
    First MiniSlash
    HK6XL Revo 4s 60mph Amsoil dealer

  3. #3
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    What kind of charger would be able to charge at that kind of amperage....

  4. #4
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    so if my batterys is a 4000mAh 25c 2s battery and it says DO NOT charge battery at less that 1C or more than 2C does that mean i can charge it at up to 8000mAh? mt charger has a max charge of 6 amps. does that mean i can charge it at that rate with out damaging the battery? or am i better of to keep charging at at the 4amps i have been charging it at?

  5. #5
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    I always charge at 6 amps for my 6000s... 3s
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  6. #6
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    I just always default to a 1C charge rate. If your battery says it can charge at 5C thats MAH/1000X5... so a 5000MAH battery being charged at 5C would be 5000/1000=5amp X 5 = 25amps. I have trouble believeing any lipo can be safely charged at 25 amps without damaging or shortening the life of the battery. 2C I can imagine and many batteries can handle that without issues. But 5C... thats LIFE battery territory.
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  7. #7
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    Quote Originally Posted by moe323
    so if my batterys is a 4000mAh 25c 2s battery and it says DO NOT charge battery at less that 1C or more than 2C does that mean i can charge it at up to 8000mAh? mt charger has a max charge of 6 amps. does that mean i can charge it at that rate with out damaging the battery? or am i better of to keep charging at at the 4amps i have been charging it at?
    I think what your saying is right?
    but let me put it this way, you have a 4000mah pack and it says you can charge it at a 2c setting then that would be 8amps
    so your 6amp charge will work, and at only 6amps

    and some of these new batteries can be charged at 5C, and that's awesome charging speeds
    First MiniSlash
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  8. #8
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    Quote Originally Posted by moe323
    so if my batterys is a 4000mAh 25c 2s battery and it says DO NOT charge battery at less that 1C or more than 2C does that mean i can charge it at up to 8000mAh? mt charger has a max charge of 6 amps. does that mean i can charge it at that rate with out damaging the battery? or am i better of to keep charging at at the 4amps i have been charging it at?
    Yes moe you are right. The max charge for those particular batts. are 8A or 8,000mAh as you said. So charging @ 6A is just fine.
    Quote Originally Posted by e-reevo's
    What kind of charger would be able to charge at that kind of amperage....
    The iCharger 206B which I have charge my Hyperion and ThunderPower batts. @ a rate of 20A for 2 at a time in Parallel. The Hyps that I have a high C-Rating of 5C, while the TPs does 6C. The TPs are 5,000mAh batts. so they can be charged as high as 30A safely. Got my charger from progressiverc.com

    I think I can safely say that charger and accessories, along with my Lipos are the best money I spent in this hobby ever. Next to purchasing my EMBE of course.
    Last edited by makaveli72; 07-02-2010 at 10:44 PM.
    **I hope there are RCs in Heaven; EMBE + 6S FTW!**

  9. #9
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    Quote Originally Posted by makaveli72
    Yes moe you are right. The max charge for those particular batts. are 8A or 8,000mAh as you said. So charging @ 6A is just fine.

    The iCharger 206B which I have charge my Hyperion and ThunderPower batts. @ a rate of 20A for 2 at a time in Parallel. The Hyps that I have a high C-Rating of 5C, while the TPs does 6C. The TPs are 5,000mAh batts. so they can be charged as high as 30A safely. Got my charger from progressiverc.com

    I think I can safely say that charger and accessories, along with my Lipos are the best money I spent in this hobby ever. Next to purchasing my EMBE of course.

    You are charging them at 2C, when you are charging them in parallel 5c would be 50amps.

  10. #10
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    ^^^ Yes, that's true. For my TP lipos which have a total mAh of 5000; and a charge rate of 6C or 30A; a 1C charge rate for two of these packs in Parallel would = 10A, 2C = 20A, 3C = 30A, 4C = 40A, 5C = 50A and 6C = 60A. I'm only charging @ a third (1/3) of the max that I could be charging the two in Parallel at. (As my iCharger only does a max of 20A) But still, they finish charging from Storage level in ~15mins. which is darn good.
    **I hope there are RCs in Heaven; EMBE + 6S FTW!**

  11. #11
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    Quote Originally Posted by filmmaker
    it depends on the size of the pack
    a 5000mah pack charged at a 5c rating would be 25amps
    and you need a big charger to charge at that rating..
    most lipos can be charged at a greater rate than 1C
    2-3C is possible with most lipos
    but most do no know this
    I do not know much but I know that. Lipos can charge at up to 5C depending on the cells used. The $20 dollar lipos? Not so much.

    Which would be kinda awesome though... only need to buy 2 batteries to have never ending bashing time?

    (Of course like all things in this hobby two is never enough... soon you will start buying batteries for street, some for bashing, some for crawling... then come the cars, and the parts ...)
    Last edited by Neuromancer; 07-04-2010 at 11:37 PM.

  12. #12
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    Quote Originally Posted by Neuromancer
    I do not know much but I know that. Lipos can charge at up to 5C depending on the cells used. The $20 dollar lipos? Not so much.
    Which would be kinda awesome though... only need to buy 2 batteries to have never ending bashing time?

    (Of course like all things in this hobby two is never enough... soon you will start buying batteries for street, some for bashing, some for crawling... then come the cars, and the parts ...)
    most lipos can be charged over the common 1C charge rating
    and a lot of people make a bid deal that their lipos are rated to be able to charge at 5C but they don't have the charger to support them, and they end up charging them at 1C anyway
    and yes most of the cheap priced packs can be charged at 2C and higher
    and again bid deal if you don't have the charger to support the 2C and higher rates
    First MiniSlash
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  13. #13
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    what about discharging lipos. I was reading the manual for the venom pro plus charger and it seems complicated to discharge. I seems like u have to know exactly how many amps etc.....How do u know? I am most likely gonna get 5000MAH 40-45C 3S batteries? When do i discharge?

  14. #14
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    Quote Originally Posted by e-reevo's
    What kind of charger would be able to charge at that kind of amperage....
    iCharger 3010B 30 amps and 1000 watts http://www.progressiverc.com/index.p...edd32043ba7e75

    FMA Cell Lab 8 30 amps and 1000 watts

    Bob

    Quote Originally Posted by Shaun78
    what about discharging lipos. I was reading the manual for the venom pro plus charger and it seems complicated to discharge. I seems like u have to know exactly how many amps etc.....How do u know? I am most likely gonna get 5000MAH 40-45C 3S batteries? When do i discharge?
    Discharge when not using AT LEAST weekly. Storing high C rated packs at full charge will cause Internal Resistance to build up.

    Discharge to 50% Storage voltage 3.80 - 3.85 v per cell .... NOT mAhs!

    I use an array of 12 volt auto light bulbs to discharge .... but prefer to just use them and charge to storage voltage. Discharging using your charger causes a lot of heat in the charger.

    Bob
    Last edited by cooleocool; 07-23-2010 at 09:41 AM. Reason: merge
    I make tap adapters and power harnesses.

  15. #15
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    Quote Originally Posted by Shaun78
    what about discharging lipos. I was reading the manual for the venom pro plus charger and it seems complicated to discharge. I seems like u have to know exactly how many amps etc.....How do u know? I am most likely gonna get 5000MAH 40-45C 3S batteries? When do i discharge?
    best way for me to discharge my packs for storage is to use them and run them to about 3.75v per cell
    no need I think to use a charger for this
    First MiniSlash
    HK6XL Revo 4s 60mph Amsoil dealer

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