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Lipo-how do you know when.....

Lipo-how do you know when.....

Old 07-08-2007, 07:21 PM
  #16  
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and if your just to lazy to look

http://www.rcgroups.com/forums/showthread.php?p=1199486

http://www.rcgroups.com/forums/showt...hreadid=139208
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Old 07-08-2007, 07:23 PM
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Hmmm...so the charger is stopping at what it says is 8.4V but the multimeter is coming in lower? So one of them has to be wrong then as long as you are checking with the multimeter right after taking it off the charger. Got a spare charger or a friend's you could test with?
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Old 07-08-2007, 07:26 PM
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Its charging now, as soon as it comes off charge, ill check it with the multimeter.

Buy the way, I havnt over discharged this battery, i was wondering what the symtoms are in case i ever do.
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Old 07-08-2007, 07:28 PM
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OK, straight off charge:
Surpernova 8.42
Muti meter: 8.34

Through Balance port: Both are reading 4.17 with multimeter
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Old 07-08-2007, 07:30 PM
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Oh not too lazy, I've seen plenty. I do believe we are talking about Orion lipos at the moment and I guess you're too lazy to differentiate between the large array of pack types available. Educate yourself on the differences before you spout off the same crap all lipo fear spreaders use. I bet if you saw a pack fire from a moron who wired a bunch of cell phone lipos together and ran in a car with a 8 turn brushed the results would scare you too. But that has nothing to do with this discussion either.

Can you find picture/video/stories about Orion packs having this same scary problem? I'd like to see you try...
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Old 07-08-2007, 08:00 PM
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Originally Posted by Sime View Post
Yes it does have CC/CV and my charger says 8.4 but my mutimeter says 8.32, so who is telling the truth.........? And I do run till completion.
thats because every charger is calibrated differently.

one charger may read 8.4v another 8.35 another 8.45...

obviosly with regards to lipo, if your charger reads a higher voltage than what it actually is, then its a good thing (in terms of safety and longevity of the lipo) because it will slightly undercharge the lipo to 8.32v

what happens when a charger actually charges at a ccv at 8.45v? could be a safety risk
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Old 07-08-2007, 08:32 PM
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I'll have to get my Mutimeter tested against a calibrated MM to see how far out it is and go from there.

So, its safe to say, that if I charge my Lipo and its only getting a voltage of say 8.0v, I should worry?
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Old 07-08-2007, 09:05 PM
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it will be under-charge
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Old 07-08-2007, 09:12 PM
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OK, I need a bit more info.
So with Lipos, you cant fully discharge it, so when it comes to charging, your charger will say for example 3500mah was put in during that particular charge, so how do you know for sure that your Lipo is capable of its full 4800mah? if at 4800mah, you lipo should read 8.4 volts, so say that if your Lipo is fully charge now at say 4000mah, the voltage will read lower.

So in a round about way, 8.4v will only be read at a fully charged 4800mah?
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Old 07-08-2007, 09:35 PM
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Sime, to see the full capacity put back in the by the charger you need to discharge the lipo completely. To do that, you need to discharge it at 4.8A, and cutoff the discharge at about 3.5V. It'll probably cost you some cycle life, though.
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Old 07-08-2007, 09:38 PM
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Bugger hey, Ill give that a miss I think. They cost $300 here in Australia.........
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Old 07-08-2007, 10:13 PM
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Those are from 2003 . . .4 years ago . . and they're not orion cells.
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Old 07-08-2007, 10:42 PM
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chart 1
This link has a chart that shows a 7.4 will peak at 8.4 volts and test after the charge any where from 8.32 volts to 8.44. I assume thats why there rated nominal. Each pack can be a little better than the next.

Chart 2
I think is the burst that each cell can handle not sure though.
Accessing this site it wont load for me on some links.

http://lib.store.yahoo.net/lib/toytr...iPo-Safety.pdf

Good stuff.
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Old 07-08-2007, 10:51 PM
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Originally Posted by Sime View Post
OK, I need a bit more info.
So with Lipos, you cant fully discharge it, so when it comes to charging, your charger will say for example 3500mah was put in during that particular charge, so how do you know for sure that your Lipo is capable of its full 4800mah? if at 4800mah, you lipo should read 8.4 volts, so say that if your Lipo is fully charge now at say 4000mah, the voltage will read lower.

So in a round about way, 8.4v will only be read at a fully charged 4800mah?
Check the percent of charge or (charge capacity setting) I have my Ice set at 110. Orion recommends 90%
If your set at 80 that may be the reason for the voltage readings.?
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Old 07-09-2007, 12:38 AM
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Mines set at 100%
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