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Old 11-03-2009, 08:35 PM   #1
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Default Newbe LIPO Question

Do you have to balance your lipo packs each time you charge them. And also do you have to discharge the pack at the end of each day of use. Any help would be great!!!!
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Old 11-03-2009, 08:45 PM   #2
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Originally Posted by Potoczak View Post
Do you have to balance your lipo packs each time you charge them. And also do you have to discharge the pack at the end of each day of use. Any help would be great!!!!
Balancing is a good idea, you do not HAVE to do it everytime, to me its like brushing your teeth, the more often its done the longer they will last.
I have heard many different opinions on storage, but here is what I do: First I NEVER discharge a lipo on a charger...I run my last race, normal 6-7 min race and that's how I leave them until the next week or whenever. I dont like to store them at 100%, and have heard others with the same opinion..
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Old 11-03-2009, 09:21 PM   #3
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+1....... On the storage thing i have been told to store them at 75% of there rating,so if you have a 5000 store it at 3750 see what im saying? Thats how they come from factory is with a 75% charge on them. Hope this helps!!
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Old 11-04-2009, 12:26 AM   #4
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+1 i balance my pack around every 10 cycles, or when im really bored or all my cars are broke. some guys never balance them but i think that is just dumb and a waste of money on lipos
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Old 11-04-2009, 04:05 AM   #5
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If the individual cells are getting out of balance when you discharge your lipo, you need to balance them. If you run without the cells balanced, you can overdischarge a cell and damge it. Low voltage cutoff looks at total voltage, not cell voltage, so if you have one that 3v and 3.4v using a 6v lvc, it will let you continue to run. You'll pull the low cell down below 3v and potentially damage it. Can also overcharge a cell this same way by charging with them out of balance.

You can check cell voltage thru the balance connection with your dvm. If your cells dont show any imbalance, you don't need to balance every time. I use a balancing charger and its just too easy not to balance every time.

You don't discharge lipo the way NiMhs required. The only time I discharge mine is when I run them.
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Old 11-05-2009, 12:07 PM   #6
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Does it take longer to charge lipo when you balance charge?
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Old 11-05-2009, 01:00 PM   #7
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no. when you charge you balance at the same time. It should'nt take hardly any time at all to balance- 1 min or so. You will have the pack balanced before it is fully charged.
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Old 11-07-2009, 08:41 PM   #8
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On a Lipo pack how do you know when the battery is going to die???
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Old 11-07-2009, 09:25 PM   #9
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Are you asking die as in when the voltage dies during a run (like a NiMH slowing way down) or die as in the life of the pack?

If its die during a run, you should be using a low voltage cutoff to protect the lipo from overdischarging. Usually an lvc is built into the esc and may or may not be adjustable. Mine are set to stop at 3.2v/cell. With a 2S, lvc kick in at 6.4v to provide me a little safety cushion. Discharging lipo below ~3v/cell can result in puffing or damaging the cell.

If its the life time ques, they kind of tail off and loose punch. Charge numbers may look ok, but performance isn't there anymore.
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Old 11-16-2009, 08:34 PM   #10
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How long can you store lipo batteries for? Possibly for months?
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Old 11-16-2009, 09:00 PM   #11
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At least if not longer. Self discharge is very, very low on lipo.
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Old 11-17-2009, 01:23 AM   #12
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try to balance every time you charge and before you store should be fine for about 3 - 4 months.
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