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Thread: lipo and nimh

  1. #1
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    lipo and nimh

    if you have a 7.4 volts 5000 2 cell lipo and a 8.4 volts 5000 7 cell which one gives you the most power and toque???? whats the difference between them???? thanks
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  2. #2
    RC Turnbuckle Jr. mike-susieq1's Avatar
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    well the nimh will be higher in voltage for about 3-5mins during the beginning of the run but soon will drop off way down there and start to lose power and torque on the other hand the lipo will maintain that voltage longer and better supply the amps so they dont drop so far and runtime will be great because of that i have found out. lipos are by far better than nimh cells for that reason and many more
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  3. #3
    RC Turnbuckle Jr. DiggerPede's Avatar
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    The 8.4v nimh is actually faster, but steadily degrades as you are running the pack. You well notice the power band dropping. A Lipo will practically keep its full power until you hit LVC/ LVD. Once you start running them and time the run you will notice a small drop the pack will feed the system.

    You will really notice how much better the Lipo feeds a brushless system as there performance is based on "c" rating x mah = a that they provide. Ex. 5000mah x 25c 1000 = 125a.

    Hope this helps ya.

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    Okay what kind of charger would u recommend to buy and what size and brand of battery thanks
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    RC Turnbuckle Jr. Greatscott's Avatar
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    I think there is a night and day difference between my 8.4NiMH and my Lipos. The Lipos deliver so much more power and have so much more power.
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    Okay what kind of charger would u recommend to buy and what size and brand of battery thanks
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  7. #7
    RC Turnbuckle Jr. mike-susieq1's Avatar
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    well you want a good lipo charger i wouldnt cheap out on this area at all i did and regret it now. Dynamite passport ultra is a 8amp lipo charger that runs both ac/dc power well worth the price though if you want to stay with AC power and not deal with the power supply servers for higher amp chargers like Icharger 106B,206B,208B, powerlabs that can run 89-229+power supply server to power them.
    Lipos take a look at either smc-racing.com, spc-specpointbatteries.com both great sites w/good prices and lipos are very good and rated right.
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    I just pm you with some questions MIKE-SUSIEG1 thanks
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  9. #9
    RC Turnbuckle Jr. mike-susieq1's Avatar
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    alright checking right now.
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    WHAT IS THE RUN TIME ON A 8200 30c 2s LIPO ON A brushed SLASH 2WD? can i run this lipo on this truck???? THANKS
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  11. #11
    RC Turnbuckle Jr. mike-susieq1's Avatar
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    PM replied with some helpful info
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    yep that is alot of helping for me im new to this stuff i replied to you
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  13. #13
    RC Turnbuckle Jr. mike-susieq1's Avatar
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    runtimes would be around 1hr+ but that long will burn out your system more likely and i dont think this would fit the slash too big
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  14. #14
    RC Turnbuckle Jr. harry697's Avatar
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    Technically, the 8.4 nimh pack should be faster and have more torque than the 2S lipo. Unfortunately, I haven't seen a nimh pack that is even halfway decent quality and most of them aren't even faster during the first few minutes compared to a lipo. If you got yourself a matched 7-cell nimh pack made with high quality cells, it should out perform a lipo for the majority of the run. Lipo packs will lose power gradually just the same as a good matched nimh pack will. I guess it's not all that noticeable for bashing because the popular opinion is that lipo runs the same from full charge until LVC, which is definitely not the case. When running on the track, I usually take the truck off the track once I have trouble clearing the bigger jumps. Voltage is usually around 3.6-3.7 volts per cell. Far from LVC, but also far from full charge. I realize heat plays into the power loss too, but the voltage drop i the main cause.

  15. #15
    RC Turnbuckle Jr. DiggerPede's Avatar
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    Welll stated harry. Another thing to remember is a Lipo is lighter than a nimh pack. So that in turn is a plus especially at the track. I'm a basher and only hit the tracks up for fun. I don't have that much confidence nor do I have a track fairly close to practice at to build this up.

    Probably some of the best nimh packs around are from ProMatch. He still used the EnerG-4600 cells, which are probably some of the best made. He also offers them in Matched/ Unmatched.

    Spend a little extra at the begining on a good charger. The 2 chargers that I have used and do me a great job are: Dynamite Passport Ultra & Racer's Edge Surecharge 2010, both have 100W PS and can charge @ 8A. The one I used now is a FMA Powerlab-6 with 600W PS and parralel charges 6 packs @ 40A. Good combo here if you have a bunch of packs that need to be charged.
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  16. #16
    RC Turnbuckle Jr. harry697's Avatar
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    Quote Originally Posted by DiggerPede View Post
    Welll stated harry. Another thing to remember is a Lipo is lighter than a nimh pack. So that in turn is a plus especially at the track.

    Thanks. And another good point. You can have a good 6-cell nimh that will perform just as good as or very close to a 2S, but the weight savings of the lipo will make the truck accelerate harder and pull the front wheels easier.

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