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Old 10-21-2011, 07:29 PM   #31
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I have ran both and i prefer lipo hands down.

They biggest thing i hated with NiMh was that, they start out good. Power isnt bad, and run time is decent too. But it doesent take long for a brushless system to really put a hurting on them and they start losing run time and performance and keep going downhill from there.

If a NiMh kept its same performance as new through the life of the pack it would be more appealing, but the LiPo's dont degrade in performance any(that i have noticed) and the run time and power is as good as ever on mine even after a year or so. I store mine in an ammo can and charge in a bag. If anything ever happens i feel like the ammo can would keep it contained.
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Old 10-21-2011, 08:08 PM   #32
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Originally Posted by ridinloudprod View Post
spam ^^^ ????
That's not spam. I do however agree with the above poster.
There's just so many choices out there, it may not be too much
longer before I actually bite the bullet and go Lipo or A123 myself.

A123's are a different chemistry than Lipo, but I heard they are much safer.
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Old 10-21-2011, 11:13 PM   #33
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I like nimh better than lipos.
I ALWAYS have a habit to fully charge my NIMH packs when im storing them.
I try to cycle them once when i take them out of storage.
The maintenece doesnt bother me at all. Lipo's you have to do more maintence.
I have never seen a lipo fire either at the tracks i race at, only puffed lipos.

I'm just used to the "plug and play" aspect that NIMH has.
Lipo's have to be balanced, Nimh's do not.
There's just so many things you have to do to a lipo to keep it's performance to last. If one small thing goes wrong you can ruin the lipo.
Every once in a while I'll see someones ESC let out the magic smoke.
That's probably the reason why i have not smoked any of my esc's.

Personally Id rather play in the snow with a Nimh over a lipo.
I do it all the time, just let the battery dry for a few hours before i recharge it.
wrong, wrong, and wrong...Balance, ever see a Novak smart tray? NIMH cells become out of balance over time just like a lipo can.

voltage is voltage NO esc on the planet has gone up in smoke because a person used a lipo vs. a NIMH pack..

IMO, you need to educate yourself about lipos (which you say yourself that you don't own) before you try and give advice on how to properly use them.

To the OP, a 2 cell lipo will out perform even the best 7-cell NIMH pack in every way. Any battery can be dangerous, lipo is no more so than NIMH. Feel free to PM more info. Some posts in this thread are correct, some are not.
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Old 10-21-2011, 11:26 PM   #34
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wrong, wrong, and wrong...Balance, ever see a Novak smart tray? NIMH cells become out of balance over time just like a lipo can.

voltage is voltage NO esc on the planet has gone up in smoke because a person used a lipo vs. a NIMH pack..

IMO, you need to educate yourself about lipos (which you say yourself that you don't own) before you try and give advice on how to properly use them.

To the OP, a 2 cell lipo will out perform even the best 7-cell NIMH pack in every way. Any battery can be dangerous, lipo is no more so than NIMH. Feel free to PM more info. Some posts in this thread are correct, some are not.
i learn all my info from ready post by this guy!

Dont be afraid to ask him questions! he knows his lipos!
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Old 10-21-2011, 11:55 PM   #35
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i learn all my info from ready post by this guy!

Dont be afraid to ask him questions! he knows his lipos!
While I thank you for the compliment I too had help in fully understanding Lipos, I give Duster 340 a lot of credit for that.

E-Racer, my post wasn't meant to be a slam on you but you either haven't learned all the things there is to learn about using lipos or you've been given bad information.

Lipo and NIMH batteries can both be dangerous if not used properly, one is no worse than the other.
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Old 10-22-2011, 12:04 AM   #36
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If you're worried about the heat transfer from a metal box, in the case of a lipo fire, I'd suggest a ceramic flower pot. That's what I use to store my lips packs.
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Old 10-22-2011, 11:36 AM   #37
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Nothing is 100% safe. In your case I would stick with NiMH.
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Old 10-22-2011, 12:20 PM   #38
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That's one thing id never do is run brushed with a lipo.
Ive seen people cook the motor that way.
I do it all the time. I don't see why a lipo would cook a brushed motor when another battery won't. A 2s lipo is 7.4v. While a nimh or old nicad may be 7.2v, that .2v isn't enough to cook the motor. Especially when we used to run modified motors on 7 cell 8.4v batteries. The only way I can see these batteries affecting brushed motors is due to longer runtimes. Then again if we used to get 5 minute runtimes and we now get 25 minute runtimes, it's reasonable to expect to have to replace brushes much more often.
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Old 10-22-2011, 06:07 PM   #39
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Nicads may be harmfull to the environment, but they were dead easy to maintain. Punch them, pull them, zap them, deep discharge them, they were (almost) bullet proof. On the other hand, I hated NiMh with a passion, basically from day one when I first charged a pack of Panasonic Stock Metals. They vented on me and got too hot after only a 15 min charge (still no idea why).

Love LiPos. No assembly required, very punchy, no "cruise mode" towards the end of a run, and imo simple to maintain if you follow directions carefully.

Re: brushed & LiPo - the extra voltage is not a problem, but brushed motors fade big time after a 6 min run and get very hot. Watch your gearing.

FWIW, I'm getting back into racing after almost a 3 year break. My LiPos (TrakPower, Tekin and IP) were sitting on my bedroom floor for around 12 months. I was worried that they made have self discharged below 6V, but when I hooked them up to my charger, the lowest volts I saw were on one Tekin pack (7.5V). Just sharing, not suggesting that anyone leave their LiPos without charging for a long period of time
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Old 10-22-2011, 06:24 PM   #40
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Lipo IMO is less dangerous than NIMH and perform way better (wheelies with LiPo vs. no wheelies with NIMH) lipo hands down
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Old 10-22-2011, 06:31 PM   #41
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Guess I made a great thread here, lots of info. Starting to feel safe about leaving a lipo in my house though as long as its been checked over do damage. voltage is correct and for extra protection inside a lipo bag, inside a small metal box inside a steel tool box
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Old 10-22-2011, 07:01 PM   #42
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...the lowest volts I saw were on one Tekin pack (7.5V). Just sharing, not suggesting that anyone leave their LiPos without charging for a long period of time
Just an FYI, you never want to store Lipos at full charge. Most modern chargers have a "storage" mode, which will charge or discharge your battery to 3.8-3.85 volts per cell. In all honesty, you are probably safe as long as your Lipo is anywhere between 3.5-4.0 volts per cell. Full charge actually damages the battery, increasing the internal resistance (I'll be damned if I remember the exact mechanism of how this happens....I am sure you can google it though ). I actually remember someone saying in a thread that every minute you leave your Lipo at full charge (4.2 volts per cell), you are damaging your battery. That's a bit of a hardcore statement, but at the very least, if you aren't using the battery within a couple days, it should be discharged to proper storage voltage. Losiho, I highly doubt that your lipos were at risk sitting at 7.5 volts (assuming this is a 2s you are talking about). Think about how long those things sit on the store shelf at about that voltage.

As a sidenote, I love using lipos. Other than not draining them beyond 3 to 3.2 volts per cell (and most new cars have a lipo cutoff to save you from this) and not storing them at full charge for a long period of time, they are pretty maintenance-free. What's nice is that you can use them, charge them, use, charge, use and charge again over and over without worry of hurting the battery or suffering from memory effect. Plus car performance and runtimes with Lipos is spectacular.

Having said all that, it's probably good practice to store them in a metal case for good measure. Better safe than sorry. In fact, I should get one too, heh.
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Old 10-22-2011, 07:22 PM   #43
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Losiho, I highly doubt that your lipos were at risk sitting at 7.5 volts (assuming this is a 2s you are talking about). Think about how long those things sit on the store shelf at about that voltage.
I don't store them with a full charge. I stop the charge at around the 8V mark. My carpeted bedroom floor with a constant steady temperature is also hardly a high stress environment
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Old 10-22-2011, 07:34 PM   #44
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My carpeted bedroom floor with a constant steady temperature is also hardly a high stress environment
Hahahahah touché my friend!
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