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Old 11-19-2012, 12:34 PM   #1
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Default LiPo Help

After 25 years in rc I finally decided to make the switch to LiPo. I decided to post this here as it is battery related but it is a few really newbie questions. Any help would be great.

1. Should I leave the balancing plug plugged in when running the truck?
2. I bought a couple 7.4 Orion 5400 mah with a 45c. What amp do people suggest charging them at? I charged them last night on 2 amp but it took FOREVER.
3. What the heck does the "c" stand for in 45c?

I know these are real basic questions and before you flame yes I did use the search function but did not find specific enough info. Thanks again!!
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Old 11-19-2012, 12:41 PM   #2
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Default Re: LiPo Help

1. No
2. Typically, you're safe to charge lipo's at "1C". What that usually means is, with a 5400 mah pack, you should be fine to charge it at 5 amps. I've never used Orion packs, but they probably have info on their website about charge rates.
3. In short, the higher the C rating, the bigger the "punch" the battery can deliver. It's like hitting the accelerator in your car... A low "C" rating would result in very little acceleration. A high "C" rating would give you whiplash! Always go with the highest C rating pack you can afford. Your Orion packs are perfect...so no need to worry about anything!
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Old 11-19-2012, 12:49 PM   #3
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Default Re: LiPo Help

Quote:
Originally Posted by ssanderson1 View Post
1. No
2. Typically, you're safe to charge lipo's at "1C". What that usually means is, with a 5400 mah pack, you should be fine to charge it at 5 amps. I've never used Orion packs, but they probably have info on their website about charge rates.
3. In short, the higher the C rating, the bigger the "punch" the battery can deliver. It's like hitting the accelerator in your car... A low "C" rating would result in very little acceleration. A high "C" rating would give you whiplash! Always go with the highest C rating pack you can afford. Your Orion packs are perfect...so no need to worry about anything!


I would not say the highest you can afford, i would say the highest "C" rating your ESC can take. (someone correct me if i am wrong) I understand it as the "C" rating is the percentage of the total Amps of the pack which are released when you pull the trigger, like starting amps or Cold Cranking Amps on your 1:1 battery.
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Old 11-19-2012, 01:38 PM   #4
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Default Re: LiPo Help

Docwolf makes a good point. I assumed your esc could take it, but you'll want to check. Also, to be more specific, the "C" rating stands for Capacity. It's the maximum safe discharge rate of your battery. Your battery for example is a 5400mah 45C pack. So it has 5.4 amps. Multiply 5.4 by 45 to get the total number of amps your battery can provide continuosly. 5.4 x 45 = 243amps.

Back to the esc thing....I'm not sure if the C rating matters. The esc will only draw as many amps as it's rated for...right? So having more than enough battery capacity isn't necessarily a bad thing? I could be wrong.
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Old 11-19-2012, 02:04 PM   #5
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Default Re: LiPo Help

Thank you, that sounds much better then what I said LOL. there have been cases where a certain companies batteries have over discharged and blown out ESCs. ideally no, it should not pull more then it can handle.
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Old 11-19-2012, 02:19 PM   #6
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Default Re: LiPo Help

I've never heard of a battery over discharging...but I'm sure it can happen, especially with cheaper batteries. However, the Orion should be fine! Hope we didn't go overboard on answering your question Carolina Scaler!
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Old 11-19-2012, 02:24 PM   #7
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Default Re: LiPo Help

lol agreed, i go with 30C personally, running a zippy 3s 500Mah hard case, it has enough C to flip my RS10 with a set of 18T H&H cobalts on it's lid.
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Old 11-19-2012, 02:46 PM   #8
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Default Re: LiPo Help

You guys have been great!! Thanks a bunch. Can't wait to get them charged and start running them. Now when I go on my hikes I will only need to bring 2 packs instead of 4.
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Old 11-19-2012, 02:59 PM   #9
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Default Re: LiPo Help

maybe not even that, i got 4 hours out of my 2s 6000 mahs, haven't ran this 3s enough to know.
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Old 11-19-2012, 05:25 PM   #10
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Default Re: LiPo Help

Is it normal for the first charge on a Lipo to not last very long? I got 10 minutes or less from a 2250 11.1 45c pack on the first charge.

This is pretty new to me.
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Old 11-19-2012, 05:44 PM   #11
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Default Re: LiPO Help

I will say....I had a nice response until Windows crashed......sigh.

Here is a repost....sorta....

Some minor clarifications.
The "C" is the "rate the pack can provide power", has NOTHING to do with the ESC. The ESC will ONLY draw what it needs, you CAN'T "over-amp" the ESC, it will only draw what it needs, thus not an issue.
The "mah" is the capacity, not the "C".

On a large pack (say...5400mah), you can get away with a low "C" since they work together.
On a small pack (say 325mah) you NEED a high "C" to get the punch.
Out of "C" & "mah", if one is small, the other needs to be high for "punch".

Charging....take the mah (5400 in this case) and divide by 1000 to get charge rate.
A 5400mah pack charges at ~5.4Amps for ~1 hour.
A 325mah pack charges at ~.3Amps for ~1 hour.

If you balance charge, the time will likely be a bit longer, depending on the pack.

Get the feeling now?

For larger packs I use "Elites" from www.CheapBatteryPacks.com
For smaller packs, I use "ThunderPower" also from CBP.

Next comp packs I get may be NanoTech (SP?) since they seem to do well for the price.

As to, "Buy the biggest 'C' you can", I would likely suggest NOT getting MaxAmps packs. They may be decent, but NOT for 2-3 times the price of other packs.
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Old 11-19-2012, 06:15 PM   #12
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Default Re: LiPO Help

Quote:
Originally Posted by Charlie-III View Post

The "mah" is the capacity, not the "C".
The "C" literally stand for Capacity... But I agree that it's more intuitive to think of the mah as the capacity of a pack.
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Old 11-19-2012, 06:35 PM   #13
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Default Re: LiPO Help

Quote:
Originally Posted by ssanderson1 View Post
The "C" literally stand for Capacity... But I agree that it's more intuitive to think of the mah as the capacity of a pack.
OK, technically you are correct, but it's misleading to most users.

If they take "C" to be capacity, then a 100C pack will last longer than a 20C pack given the same mah.
This is incorrect.
The 100C pack can DISCHARGE at a higher rate than a 20C pack with each pack having the same mah.

While I may be "incorrect" stating "mah" is capacity & "C" is discharge rate, I think it is a better set of terms for ~90% of users.
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Old 11-19-2012, 06:38 PM   #14
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Default Re: LiPO Help

Quote:
Originally Posted by Charlie-III View Post
While I may be "incorrect" stating "mah" is capacity & "C" is discharge rate, I think it is a better set of terms for ~90% of users.
Totally agree. I should have clarified the two initially.
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Old 11-19-2012, 06:50 PM   #15
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Default Re: LiPo Help

Quote:
Originally Posted by Docwolf View Post
lol agreed, i go with 30C personally, running a zippy 3s 500Mah hard case, it has enough C to flip my RS10 with a set of 18T H&H cobalts on it's lid.
but how much time do you get out of them?
i have 3 turnigy 3s 500mah batteries and i dont get squat out of them..

55t novak, 15t pinion/87 spur
6lb 12oz ax10
i might get 5 minutes from each.....

bought a parallel adapter so i can run 2 and see if that is better.....

id say 1300mah minimum for some good fun....
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Old 11-19-2012, 07:02 PM   #16
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Default

I run 3000mah 40c 3s blue lipo packs from hobbypartz.com and I get almost 2 hours on my scx10 scaler with 45t motor. Truck weighs 8.5 pounds.

Same battery lasted only 6 minutes in my 4x4 slash.

The higher the mah the longer the run time.

Sent from my DROIDX using Tapatalk 2
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Old 11-20-2012, 04:54 AM   #17
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Default Re: LiPo Help

Quote:
Originally Posted by RootBreaker View Post
but how much time do you get out of them?
i have 3 turnigy 3s 500mah batteries and i dont get squat out of them..

55t novak, 15t pinion/87 spur
6lb 12oz ax10
i might get 5 minutes from each.....

bought a parallel adapter so i can run 2 and see if that is better.....

id say 1300mah minimum for some good fun....
My guess is that it's a typo, it should read 5000mah.
Your runtime from a 500mah sounds about right. Not much different than my comp rig with small packs.
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Old 11-20-2012, 07:53 AM   #18
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Default Re: LiPo Help

Quote:
Originally Posted by Charlie-III View Post
My guess is that it's a typo, it should read 5000mah.
Nope.
I remember from his other posts when he bought those. And it's highly unlikely he'da gotten as smokin' good of a deal on a 5,000 mAh pack unless it resembled a stack of ketchup packets.
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Old 11-20-2012, 08:15 AM   #19
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Default Re: LiPo Help

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Originally Posted by Trubble View Post
Nope.
I remember from his other posts when he bought those. And it's highly unlikely he'da gotten as smokin' good of a deal on a 5,000 mAh pack unless it resembled a stack of ketchup packets.
ding ding...

yup i got 3 x 500mah 3s turnigy lipos for $5 each... so for $15 i got 3 of them... for me to "try" lipo...
i have a parallel adapter coming to make them into 3s 1000mah...

also going to buy a larger pack as well.. just havent gotten to it yet...

im just letting the OP know that while there are small ones out there and they work well.. you dont get as much time out of them.. so yes a 3000-5000mah will give more run time.. but also weigh more and are bigger..
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Old 11-20-2012, 09:08 AM   #20
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Default Re: LiPo Help

Quote:
Originally Posted by RootBreaker View Post
but how much time do you get out of them?
i have 3 turnigy 3s 500mah batteries and i dont get squat out of them..

55t novak, 15t pinion/87 spur
6lb 12oz ax10
i might get 5 minutes from each.....

bought a parallel adapter so i can run 2 and see if that is better.....

id say 1300mah minimum for some good fun....

sorry that should say 5000 mah, not 500 not sure yer on run time, 2 hours Saturday then i shelled the front CVs. it is a 30c pack, i am hoping for 3.5 hours run time total.
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