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  1. #1
    RC Enthusiast
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    Specific advice for battery charging

    I have a Triton Jr. charger that I use for my heli. It has a peak detector and allows me to set the amount of charge in .1 amp/hr increments.
    I also have two sets of batteries, Venom 5000 7 cell 5000mah 8.4 volts (from LHS), and Promatch EnerG 4600's 7 cell 4600mah 8.4 volts (forum recommended).

    Exactly what amp setting should I use?
    The venom packaging said 4 amps/hr would work but 3/hr is better. When I do that they get rather hot at the end of the charging cycle. Right now I am charging at 2 amps/hr just to be safe.
    I don't want the math just the number. Not to be rude, I have done the math just don't have any practical experience. Also is there anything specific that I should watch for while charging?

    Thanks
    My wife wont touch the heli but she loves my truck

  2. #2
    RC poster
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    Jun 2009
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    Heating up during a charge is perfectly normal... A temp. of about 42 degrees CELSIUS (sorry.. i'm Dutch) is recommended as a cut-off point by most of the manufacturers.

    Charging ni-mh's is usually done at a rate of 1C , so that's 5 amp. for the Venom and 4.6 amp. for the Promatch.

  3. #3
    RC Qualifier
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    Nov 2008
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    i do 3 amp for my 7 cell 4600 promatch, it takes a bit longer but it keeps the temps down. If you charge at 5 amp you will probably get the battery temps to high and possibly cause venting of the cells, but your initial power surge would be greater for the first couple of high speed runs. The higher amp charge the quicker the the degrading of the battery pack.

  4. #4
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    Charging at 1C should be perfectly safe... A quote from the Pro-Match site on charging :

    2: Charging: There are so many theories of charging out there I get dizzy listening to them. Let me share my thoughts with you.. What is the best charge rate?
    There is no single answer here.The rate at which you charge a battery pack only affects the performance characteristics slightly. If you use a lower charge rate you will see better run time with less voltage. If you use a higher charge rate you will see higher voltage with less run time. Using a higher charge rate will increase the risk of cells venting so be very careful when using high charge rates (especially above 6 amps). You may notice that we final match our cells with an 8 amp charge rate. Remeber that we use Turbomatcher 8 * cell matchers that allows us to monitor both voltage and temperature of each cell seperately as it is being cycled. Our peak detection values can be adjusted in one thousandth of a volt increments giving us much more precise control over each cell. We do not recommend charging above 6 amps for charging packs
    1C for the 4600 would be "only" 4.6 amps well within de 6 amp range they refer to...

  5. #5
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    Thanks for the heads up. As I said, no practical experience.
    I will up it to 3 amps.
    My wife wont touch the heli but she loves my truck

  6. #6
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    42 degrees celsius works out to 107.6 Fahrenheit (gotta love spell check)

    Now I see why I was freaking out. When I picked up 100+ degree batteries my monkey brain kicked in.

    -Bad, very bad!!! Hot battery not good!!! Ook!!!-
    My wife wont touch the heli but she loves my truck

  7. #7
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    After actually reading Dutch Summits second reply I think I will kick it up to 4 amps/hr.

    Thanks again folks!
    My wife wont touch the heli but she loves my truck

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