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Thread: LiPO and Traxxas XL5??

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Old 03-14-2010, 11:29 PM   #1
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Question LiPO and Traxxas XL5??

Trying to get a little more run time from my traxxas waterproof XL5 and i was wondering if i can run LiPo on it without burning it out?

I've read that some people are running up to 11.1v without any issues....can anyone shed some light on what the max i can go with LiPo (traxxas says that you can run up to 4-8 Cells (4.8 to 9.6 Volts DC)) What does that mean? Is the XL5 only able to run at max 9.6 volts?

Also, what does someone mean when they refer to a battery like this 11.1 30c? What does the "C" mean after the 30?

Sorry for all the N00Bish talk but my brain hurts and i thought i'd ask the battery and tech head Gurus.

Thanks,
Twisted
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Old 03-14-2010, 11:48 PM   #2
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I run a 2s on mine with no problems. That 9.6v limit is there for a reason. Some people like to press their luck. I wont cause I'm not rich enough to just try a 3s and see if it goes poof or not.
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Old 03-16-2010, 01:24 AM   #3
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Quote:
Originally Posted by GB's 05 View Post
I run a 2s on mine with no problems. That 9.6v limit is there for a reason. Some people like to press their luck. I wont cause I'm not rich enough to just try a 3s and see if it goes poof or not.
GB by 2s do you mean two cells? also what voltage is the battery your using?
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Old 03-16-2010, 01:37 AM   #4
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2S = two cells = 7.4V or 3.7V per cell

3S x 3.7V = 11.1V, so the most you can run on the XL5 is 2S. Unless you're feeling lucky

C Rating is how many amps the battery can supply which is depends on the capacity.

For example, a 30C 3000mah lipo can provide 90amps (30 x 3amps or 3000mah).

If you have a higher capacity battery, you can still get the same amount of power with a lower C-rating.

For example, a 20C 5000mah battery can supply 100amps (20x5amps or 5000mah).

Last edited by K_B; 03-16-2010 at 01:42 AM.
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Old 03-16-2010, 01:39 AM   #5
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Originally Posted by K_B View Post
2S = two cells = 7.4V or 3.7V per cell

3S x 3.7V = 11.1V, so the most you can run on the XL5 is 2S. Unless you're feeling lucky

KB thanks for clearing that up...so im guessing that you can get 2S LiPos that are more than 7.4 correct?
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Old 03-16-2010, 03:37 AM   #6
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Nope... each cell is 3.7V, so it goes in increments of 3.7:

1 cell = 3.7V
2 cell = 7.4V (2 x 3.7)
3 cell = 11.1V (3 x 3.7)

If you want to run the maximum voltage that XL5 can handle, you'd have to run an 8-cell NiMH pack which is 9.6V.

I just re-read your post. You're looking for runtime, correct? In that case, you're getting voltage confused with capacity. The capacity of the battery is measured in mAh (milliamp-hours). The higher the number, the more runtime you get. For a crawler, you want small, light batteries, so you can get 2S lipos around 1300mah or so which gives you around 30-45 minutes of runtime depending on what kind of crawler you have.

You can get 2S lipos with as much as 12,000mah, but those are huge and won't exactly fit in a crawler.

Last edited by K_B; 03-16-2010 at 03:42 AM.
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Old 03-16-2010, 06:38 AM   #7
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When charged they will be 8.4
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Old 03-16-2010, 11:17 PM   #8
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An additional issue to consider to, is that there is no LIPO alarm or cutoff on the esc, so you will need to address that. Some people just wait to it slows down a lot, but the problem is that if the voltage goes too low, the pack is DOR, DOA, RIP!
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Old 03-16-2010, 11:49 PM   #9
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Quote:
Originally Posted by wanantrdsc View Post
An additional issue to consider to, is that there is no LIPO alarm or cutoff on the esc, so you will need to address that. Some people just wait to it slows down a lot, but the problem is that if the voltage goes too low, the pack is DOR, DOA, RIP!
Yup, what he said on the lack of any kind of li-po cut off, the EVX2 is the same way, but I'm not sure off hand about the XL2.5's from teh 16th scale trucks. What motor are you running with that ESC too, I've gotten away with higher voltage so long as I'm far away from the ESC's motor limit in the past on other brand ESC's.
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Old 03-17-2010, 01:30 AM   #10
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Quote:
Originally Posted by K_B View Post
Nope... each cell is 3.7V, so it goes in increments of 3.7:

1 cell = 3.7V
2 cell = 7.4V (2 x 3.7)
3 cell = 11.1V (3 x 3.7)

If you want to run the maximum voltage that XL5 can handle, you'd have to run an 8-cell NiMH pack which is 9.6V.

I just re-read your post. You're looking for runtime, correct? In that case, you're getting voltage confused with capacity. The capacity of the battery is measured in mAh (milliamp-hours). The higher the number, the more runtime you get. For a crawler, you want small, light batteries, so you can get 2S lipos around 1300mah or so which gives you around 30-45 minutes of runtime depending on what kind of crawler you have.

You can get 2S lipos with as much as 12,000mah, but those are huge and won't exactly fit in a crawler.
KB in terms of using NiMH how would you calculate volts per cell? Im planning on getting a integy 55T but right now running a stock tamiya silver can with the XL5

...and im guessing that different batteries can come in different "MAHs". How would i determine my correct mAH for my usage?

Quote:
Originally Posted by GB's 05 View Post
When charged they will be 8.4
Are you reffering to 2s when fully charged come up to 8.4?

Quote:
Originally Posted by wanantrdsc View Post
An additional issue to consider to, is that there is no LIPO alarm or cutoff on the esc, so you will need to address that. Some people just wait to it slows down a lot, but the problem is that if the voltage goes too low, the pack is DOR, DOA, RIP!
I have to look at if anyone is running a LiPo alarm on any of there rigs...i guess don't run your LiPos till they are dead?

Quote:
Originally Posted by BJoe View Post
Yup, what he said on the lack of any kind of li-po cut off, the EVX2 is the same way, but I'm not sure off hand about the XL2.5's from teh 16th scale trucks. What motor are you running with that ESC too, I've gotten away with higher voltage so long as I'm far away from the ESC's motor limit in the past on other brand ESC's.
Right now im running a stock Tamiya silver can in my CR01 but eventually looking into the Integy 55T
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Old 03-17-2010, 02:13 AM   #11
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"im guessing that different batteries can come in different "MAHs". How would i determine my correct mAH for my usage?"
MaH is the capacity of the battery. For example, on a car consider the mah as the gas tank, the larger the MaH the larger your tank.The C rateing is your discharge rate. The higher the C rateing the more amps your battery can put out at a time.
A 2S 5000MaH 30C battery and a 2S 1300MaH 30C battery are both going to put out the same power it's just the 5000MaH battery can do it longer.

"Are you reffering to 2s when fully charged come up to 8.4?"
Yes, 4.20 per cell.

"I have to look at if anyone is running a LiPo alarm on any of there rigs...i guess don't run your LiPos till they are dead?"
Correct, Never run lipo's below 3.0 per cell is what most MFG's recommend but to be safe try not to go below 3.2 per cell.

Theres not an external lipo cut-off made yet for the blue case Traxxas XL-5 ESC,alarms yes but cuttoff's No.
If you can find an older XL-5 in the yellow caseing(think Rustler) it WILL work wih a lipo cut-off like a Novak smart stop.
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Old 03-17-2010, 09:00 AM   #12
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I've ran 2s/3s on xl-5's with no cutoff. when power felt to drop I'd check lipo w/cell spy. 3s is pushing it thou.
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Old 03-18-2010, 01:52 AM   #13
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who makes a cell spy?
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Old 03-18-2010, 02:14 AM   #14
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Quote:
Originally Posted by transambill View Post
.
A 2S 5000MaH 30C battery and a 2S 1300MaH 30C battery are both going to put out the same power it's just the 5000MaH battery can do it longer.

Thats only true in terms of voltage, the 5000mah will put out 150 amps where as the 1300 will only supply 39 amps.


In terms, just run a 4000-5000mah 2s lipo with a novak 2s smart stop, you will have plenty of amps, super long runtime and you will have a low voltage cut off.
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Old 03-22-2010, 11:04 PM   #15
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Originally Posted by Satan6907 View Post
In terms, just run a 4000-5000mah 2s lipo with a novak 2s smart stop, you will have plenty of amps, super long runtime and you will have a low voltage cut off.
You cant do that with a Traxxas XL5.
The older yellow case one's yes but the recent,more common blue case XL5's like found in the Slash and Rustler WILL NOT WORK with a Novak 2s smart stop.
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Old 03-23-2010, 12:52 AM   #16
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Quote:
Originally Posted by transambill View Post
You cant do that with a Traxxas XL5.
The older yellow case one's yes but the recent,more common blue case XL5's like found in the Slash and Rustler WILL NOT WORK with a Novak 2s smart stop.
thanks transambill for the heads up...i was looking into that for a possible solution...

...so basically i can run any battery combo whether be NiCad, NiMH, or LIpo just don't exceed the 9.4 volt capacity of the XL5 correct?
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Old 03-23-2010, 02:56 AM   #17
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Yes
If you want to run lipo you can install a voltage alarm that plugs in and beeps or flashes a lite or both when it reads 3.2 per cell. Myself I've never seen XL5's live very long on lipo. If it was me I would run a good matched cell Nimh pack and be done with it.
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Old 06-19-2010, 11:02 PM   #18
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Quote:
Originally Posted by transambill View Post
"im guessing that different batteries can come in different "MAHs". How would i determine my correct mAH for my usage?"
MaH is the capacity of the battery. For example, on a car consider the mah as the gas tank, the larger the MaH the larger your tank.The C rateing is your discharge rate. The higher the C rateing the more amps your battery can put out at a time.
A 2S 5000MaH 30C battery and a 2S 1300MaH 30C battery are both going to put out the same power it's just the 5000MaH battery can do it longer.

"Are you reffering to 2s when fully charged come up to 8.4?"
Yes, 4.20 per cell.

"I have to look at if anyone is running a LiPo alarm on any of there rigs...i guess don't run your LiPos till they are dead?"
Correct, Never run lipo's below 3.0 per cell is what most MFG's recommend but to be safe try not to go below 3.2 per cell.

Theres not an external lipo cut-off made yet for the blue case Traxxas XL-5 ESC,alarms yes but cuttoff's No.
If you can find an older XL-5 in the yellow caseing(think Rustler) it WILL work wih a lipo cut-off like a Novak smart stop.
hey what if the battery 1200mah 10c how can i run it
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