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Old Dec 24, 2012, 07:36 PM
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United States, CA, Huntington Beach
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What C rating should I charge my Lipo's at?

Hi Guys, I've always charged my Lipo's at 1C. I recently purchased some nano techs that say they can be charged at a MAX 8C! I'd like to know if I can SAFELY charge my Lipo's a bit faster(not necessarily 8C, I am thinking more along the lines of 2-3C) WITHOUT prematurely wearing them out?

Thanks!
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Old Dec 24, 2012, 07:45 PM
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Yes. There are many of us who have been charging lipolys at 2-3C charge rate (and even higher) for many years with no detriment to longevity.

Much more important than charge rate is always performing balance charges and never storing at full charge.

Mark
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Old Dec 25, 2012, 05:13 AM
A man with too many toys
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I charge my LiPo’s at 3C and higher and have never had a problem with shortening the life. The new LiPo batteries are designed for high charge rates. I did have to get a Power Lab 8 V2 as my old charger just would not put out enough watts.

.
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Old Dec 25, 2012, 05:52 AM
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I too have been charging at 2 and 3 C without any reduction in battery life.

Glen
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Old Dec 26, 2012, 07:58 PM
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I am just getting into electric after 30+ years in the building and flying of nitro planes. I have 25C batteries. 11.1v 2650mah tell me about proper charge current. I do plan only a balancing charger. HELP!
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Old Dec 26, 2012, 08:10 PM
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Set a balance charge for 11.1v 3S and set the charge rate for 5 amps.That would be a 2c charge and would have your battery charged from dead to full in a 1/2 hour.
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Old Dec 27, 2012, 04:33 AM
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Quote:
Originally Posted by Red_Jeepster View Post
I am just getting into electric after 30+ years in the building and flying of nitro planes. I have 25C batteries. 11.7v 2650mah tell me about proper charge current. I do plan only a balancing charger. HELP!
Hi,
As said, 2 times the capacity number, in your case 2 x 2650 = 5300 mA(5.3 amp), is not going to be any problem with most moderna LiPo (some 1 cell LiPo do not want to be charged with more then 1C).
In the charger You set LiPo as type and how many cells Your LiPo battery has. Each cell in a LiPo battery has a standard voltage of 3.7 volt per cell so a 3 cell LiPo battery has 11.1 standard (nominal) voltage. It is written on the LiPo pack.
Normally You use the balance connector also in the charger and connect it to the LiPo battery so all cells in the battery pack gets charged to full (4.20 volt per cell) in controlled and proper way. As cells ages they takes little longer to get balanced and reach 4.20 volt and that is normal. You could maybe expect, with proper care, hundreds (maybe 200+) cycles on a normal quality LiPo pack. If You follow just some very basic rules of LiPo care they should last long time: balance charge as often as possible (at the field I charge to 95% usually since it goes faster, the last 5% is what takes time to balance upp to full in my experience), storage charge the LiPo pack when not in use (if I do not plan to fly next day or two I storage charge them and that is about 60% capacity, it is not important value but between 50-70% is OK).
And do not empty (at flying or otherwise) the LiPo below 20% capacity since they can get damaged if they are drained below that, at least repeatadly, and absolute miniumum is not below 10% according to some LiPo manufacturer for example Hyperion say that. But 20% capacity left after landing (in Your case 0.20 x 2650 mAh = 530 mAh should be left) is the general rule to follow. You use some trail and fly with a timer to find out how long You can fly without empty the LiPo below 20% of it's capacity. Then when You charge you take notes how many mAh You can get into the LiPo pack to get it full and that way You can figure out proper flying time to set in the radio timer/alarm. It is easy to find out this. Just remember if you at some flights run the motor on higher power (longer times) then You normally would do You should land little earlier to not exceed the 20% capacity left rule by to much.

I do not know if You have figured out the C rating of LiPo but with Your 25C battery it is that it can deliver current up to 25 times the capacity number, 25 x 2650= 66250 mA (66.250 amp). If Your setup will require more current than this You buy higher C rated battery, like 30, 35, 45, 65C (higher C is usually more expensive and usually little heavier). You use a so called Wattmeter or a current clamp meter to know how much current your setup draw.

If You need advice on charger and power supply just read here in this forum, many to choose from and You should be able to find something that fit Your need and wallet,

/Bo
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Old Dec 27, 2012, 07:53 AM
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Guys, we're happy to help but these questions have been answered over and over again... a simple Search or browsing the stickys at the top of this board will yield the answers you seek.
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Old Dec 27, 2012, 02:23 PM
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Guys, we're happy to help but these questions have been answered over and over again... a simple Search or browsing the stickys at the top of this board will yield the answers you seek.
The redundancy is getting to ridiculous levels. I've started to loose interest in even looking at this board it's that bad.
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Old Dec 28, 2012, 06:44 PM
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The redundancy is getting to ridiculous levels. I've started to loose interest in even looking at this board it's that bad.
A searchable Wiki might help to organise things?

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Old Dec 30, 2012, 06:39 AM
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IT has been my experience with Nano Tecs that any more than 2 c and the cell voltage starts spreading.I balance every time and have plenty of batteries so i only go at 1.5 c just because i am not in a hurry. IMHO The NanoTecs are not all they claim to be. perhaps some of the domestically purchased batteries have better success with high c rate charging but i have not has that experience with NanoTecs. I went with some 2200 zippys because the last 4 @ 40 c seem to hold up better than a 35-70 c nano. its bad when a NEW 2 cell 50000 40+c Nano tec isn't balanced by the third charge. NOT IMPRESSED WITH NANO TECS
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Old Dec 30, 2012, 10:53 AM
BWX
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Quote:
Originally Posted by w1indse7 View Post
Hi Guys, I've always charged my Lipo's at 1C. I recently purchased some nano techs that say they can be charged at a MAX 8C! I'd like to know if I can SAFELY charge my Lipo's a bit faster(not necessarily 8C, I am thinking more along the lines of 2-3C) WITHOUT prematurely wearing them out?

Thanks!
Why would you charge faster than 1C? Whats the purpose behind it, your faster at the field, charge faster at the field?

I purchased more packs and a (360watt)Dymond quatro charger, 4 packs in a hour.

Okey only 80watt per output but enough for my pack, only fly with 3s and 4s 2000-2500mah.

Yes you can savely charge at a higher C (as long the manufacture says it can) but i think they wear faster.
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Old Dec 30, 2012, 12:01 PM
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Originally Posted by BWX View Post
Why would you charge faster than 1C? Whats the purpose behind it, your faster at the field, charge faster at the field?

I purchased more packs and a (360watt)Dymond quatro charger, 4 packs in a hour.

Okey only 80watt per output but enough for my pack, only fly with 3s and 4s 2000-2500mah.

Yes you can safely charge at a higher C (as long the manufacture says it can) but i think they wear faster.
It is totally safe to charge at 2c, it takes less time to charge which means more flight time on fewer batteries.

If you follow the forum yu will see that it does not wear of damage your battery to charge at 2c

Charging at 1c is like driving on the freeway at 55 mph when the speed limit is 70 MPH, not really dangerous but why would you go that slow.

Dennis
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Old Dec 30, 2012, 12:38 PM
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My rule of thumb, if I'm charging at home for a flight later, I charge at 1c, simply because I'm in no hurry at that point, and less current=less chance of heating up a battery or lipo fire. At the field, 2-3c is normal, as we all want to get as many flights is as we can.
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Old Dec 30, 2012, 08:01 PM
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Grass Valley California
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certainly nothing wrong with charging at 1c, but there is no increased risk of charging at 2c
My batteries cool down at a 2c charge right after a flight.

Dennis
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