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  1. #1
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    Batteries Explained

    Hi Everyone,

    I have been in the hobby a very long and understand Lipo's incredibly well. This is a guide from what I have gathered over the years. This is a basic guide for the beginner to understand LIPO's and the ratings.

    Some of this may clash with TRAXXAS instructions of LIPO care and Safety. If you have any doubts about what is stated below please follow TRAXXAS instructions.

    If you do not understand something please ask.

    That being said I am going to break this down to be as simple as possible... A simple summary can be seen at the end.

    Which Battery to buy?

    Each Lipo has several different ratings, if you are unsure of which battery to use always safe to go with what is recommended by the manufacturer.
    If that battery is unavailable you may use alternative options.

    1) Voltage

    Voltage of a battery is decided by how many cells are in a single battery.
    There can be anywhere from 1S all the way to 7S.
    For Lipo batteries a single cell in a battery is considered 3.7 Volts.
    This means that a 2 cell (2S most commonly labeled on a battery) is 7.4 Volts and a
    3S (3 cell battery) is 11.1 Volts.
    The higher the voltage the more Power you get.

    BE SURE TO CHECK THAT THE TRAXXAS VEHICLE CAN SUPPORT THE
    VOLTAGE YOU ARE PUTTING INTO IT. I.E the Slash 2WD can handle a 2S Lipo but not a 3S.

    2) MAH (Milli-Amp Hour)

    This is the capacity of the battery, almost in comparision to the fuel tank in a car.
    It determines the amount of run time you will receive from a battery.

    i.e. a 5000 MAH battery will give you more run time than a 3000 MAH battery.

    This being said the 5000 MAH battery will be quite a bit heavier than the
    3000 MAH. If you purchase to large of a battery you may have trouble fitting the
    battery into the vehicle itself as the physical size of the battery may be too large.

    3) C ratings

    Here we have two different rating a charge rating (usually between 1C and 5C)
    and discharge ratings (25C - 70C).
    To explain further:

    1C is basically 1*(MAH/1000).
    So if we have a 5000 MAH battery, 5000/1000 = 5, then 1*5 = 5 Amps.
    This means that 1C is 5 amps.


    Charging - Charging is always safe to charge any battery at 1C.
    So for a 5000 MAH battery charge at 5 amps, or for a 2700 MAH battery charge
    at 2.7 amps. Any charge rate greater than this could potentially wreck a battery so be cautious.

    here is a table for charge rates:

    C rating MAH Charge Rate
    1 50000 5 Amps
    2 50000 10 Amps
    3 50000 15 Amps
    4 50000 20 Amps
    5 50000 25 Amps

    The higher the charge rate the quicker the charge, so at 1C a battery will take 1 hour,
    at 2C the battery will take 30 mins,
    at 3 C the batetry will take 20 minutes to charge so on and so forth.
    The TRAXXAS EZ-PEAK DUAL can only charge 8 amps for output or 4 amps when using both outputs.

    So if charging 2 5000 MAH batteries and the TRAXXAS charger at 4 amps will approximately take
    1 hour and 15 minutes to charge both batteries.
    If only charging 1 5000 MAH battery at 8 Amps then it would take approximately 40 mins to charge.



    Discharge Rate - this is how much umpf a battery can supply,
    theoritically a 65C 5000MAH battery can discharge 325 amps safely when fully charged,
    and a 25C 5000MAH battery can discharge no more than 125 amps safely however
    that is not why this number matters.

    Think about your car, as you drive it the fuel level goes down,same thing happens with Lipos
    as you drive it the MAH's available go down.
    So now after driving for 40 minutes there might only be 1000 MAH left in the battery.
    So now that 25C battery can only discharge 25 AMPs,
    while the 65C battery can discharge 65 amps.

    Do Not misunderstand this portion, as all TRAXXAS batteries have only a 25C discharge rating.
    Some of you might say well that's not good.

    Let me say this I cannot tell the difference between a 25C TRAXXAS battery and a 65C battery in my
    TRAXXAS Slash 2WD because simply put the Slash does not draw enough current.
    Furthermore why spend the money on 65C battery for a vehicle that doesnt need it.



    How to Charge - This applies to the EZ PEAK and EZ-PEAK DUO ONLY

    Read the Manual for the TRAXXAS charger.
    It is the simpliest charger on the market I believe I have seen, certainly one of the cheapest cost wise.
    They even make adapter so that you may use third party batteries with this charger (YAY TRAXXAS).
    Keep in mind this Charger will only handle 2S or 3S batteries.

    Always charge with what is called a balance charge. This keeps the individual cells within the battery equal.
    Aka in a 3S battery the charger will
    ensure that the cell voltage of Cell #1 is within its tolerance (Usually .05 of a volt or so) of Cell #2 and Cell #3.

    NEVER EVER CHARGE A DAMAGED BATTERY OR LEAVE A BATTERY UNATTENDED WHILE CHARGING!!!!!!!!!!

    Breaking in

    Not something I do very often and I probably should which is breakin the batteries.
    This "Wakes up" the cells within the battery and allows the battery to
    live longer.

    To break in a battery run the battery to about 70% of it's capacity for the
    first five or so runs you use it. Basically if you are to supposed to get 45 mins of
    run time out of the battery cut that to 10 mins for run #1, then to 12 mins, then 13,
    then 15 and 15 min runs.

    Storage

    To Store a Lipo the healthiest option for the lipo is to be at 3.8/3.85 volts per cell.
    If using the EX PEAK DUO there is a mode there that says storage.
    So run the battery down past 50% then throw it on the charger.
    I only do this to batteries that are not going to be run within the week. Any longer than
    that I put mine into storage mode.

    STORE THE LIPO SOMEWHERE COOL.

    I keep my Lipos in fire proof bags just incase.

    End of Life

    DO NOT THROW BATTERY INTO GARBAGE

    TRAXXAS has an amazing program to trade in batteries every year.
    They are the only ones that does this and another reason I use their batteries.

    *****RIGHT ON THEIR WEBSITE*******

    Lifetime Battery Exchange Program
    Traxxas stands by Power Cell LiPo batteries with the best warranty and exchange program available. For the first year of ownership, Traxxas will replace any battery found to be defective at no cost. After one year, any Power Cell LiPo battery in any condition can be exchanged for a new equivalent battery for just 50% of the new pack's retail price, no questions asked.

    HOW AWESOME IS THAT!!!

    If you dont take advantage of that I recommend to contact the local fire hall or
    dump to see as to the best/safest method to dispose of a Lipo

    In summary:

    Voltage - use what is recommended
    Capacity (MAH) - Use what is recommended (the larger the number the more run time)
    C rating - Anything above 25C discharge rating will work fine.
    Charging - Always balance charge and charge at 1C.. NEVER CHARGE A DAMAGED BATTERY OR LEAVE BATTERY UNATTENDED WHILE CHARGING.
    Storage - Use the storage setting on the charger after running battery down
    End of Life - Contract TRAXXAS or Local fire hall, DO NOT THROW INTO GARBAGE


    Again this meant for the Average TRAXXAS consumer who is looking at getting a TRAXXAS RC with a LIPO.
    If you have any questions please PM me or contact TRAXXAS themselves, whom are excellent.

  2. #2
    RC poster
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    Many thanks. I'm new here and I found what you wrote very helpful to me. Thx again.

  3. #3
    RC poster
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    I have a question. I have a 1300mah 3s lipo battery, 3s=11.1V, But i really don't know the mean of mAh. I know 1000ma=1A, h=1 hours,but What does the mAh represent? Does it represent the energy released ?
    Last edited by Double G; 09-22-2016 at 07:00 AM.

  4. #4
    RC Competitor
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    1000 mah is the capacity of the battery. It means 1 amp can be drawn for one hour from the battery. Think of it as the size of the gas tank in your car. a 3000 mah can supply 3 amps for 1 hour.
    Last edited by RcManChild; 09-27-2016 at 09:07 PM. Reason: grammar

  5. #5
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    Well written, the only thing i'd say, is do go with a better discharge rate.

    Though 25c maybe sufficient for today, at some stage you'll most likely be upgrading your motor for something better and perhaps even a new ESC. Then you might be limited to the fact that you've gone and bought all your lipo's at 25c only. At least if you bought 65c rated batteries you'll have all future motor and ESC upgrades covered.

    Also most decent batteries are fine at being charged at 2C. So if you have say a 6500mAh battery and have invested in a decent charger setup that does more than the 8amp Traxxas one, then go ahead and charge it at 13amps. At the end of the day, you want to be able to bring your batteries out from a storage charge in minutes, as appose to 30mins, right? Who wants to wait around ?

    A 20amp charger like an iCharger 206b is my recommendation. Can be had for a little over $100 (plus you need to power it, and using a redundant server PSU, is the best bet for that) $25 approx off eBay and a little modding involved. DPS-600PB is what i used. That gives me up to 20amps of charge.. I actually had a PowerLab 6 that would have given me upto 40amps, should i have ever felt the need to charge mutiple batteries at once, at 2C, but that died on me, and their CS was very very bad.. So went with an iCharger instead.

    This thread here, has everything you need to know about converting a server PSU.

    Hope that helps.
    Last edited by thedoc46; 10-27-2016 at 10:55 AM.

  6. #6
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    It Increase the weight of the truck, but more it increase the inherent amount of torque required to turn the same at the same rate of speed. Simply put for The Xmaxx, Revo brushless and D41 boat I personally would not run anything less than 50C due to the amount of power these machines take.

  7. #7
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    Great post. Can you tell me what is the minimum voltage that a 3s 5000May battery will charge at? With the easy peak I'd charger.

  8. #8
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    So off topic but i was wondering if my motor can handle a 3s lipo. I have a brand new hobbywing 10bl60 esc and a racers edge 3600kv. I can't find any information on it.

  9. #9
    Marshal Double G's Avatar
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    It's not if the motor can handle it, it is if the ESC can. Ask the manufacturer(s).
    The Super Derecho

  10. #10
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    The esc says 2-3s so it should be fine then huh?

  11. #11
    Marshal ksb51rl's Avatar
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    As stated above, for this kind of product SUPPORT, please contact the manufacturer.
    Alt-248 on the number pad =

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