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Trying to save a lipo?

Trying to save a lipo?

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Old 05-11-2010, 06:38 PM
  #16  
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Lipo chargers won't charge with a lipo that has a voltage reading thats below 3v/cell, so a 4S needs to be at 12v or better. There are inaccuracies in these chargers so its not surprising if you go to 12v on NiMh mode it may not charge yet as a lipo. I try to get teh voltage up to 12. something.

Another tip - 1.0amp on NiMh rate will cause voltage to go up too fast unless the capacity is large. I use 0.5amp - this also gives a more balanced charge to the cells at this lower rate.

The best way to fix low voltage cell issues is with a lipo charger that charges only thru the balance connector. If you're going to use lipos from HobbyKing, next time you see this in stock and are ordering, get one -

http://www.hobbycity.com/hobbycity/s...Charge_Capable


I have one and its already paid for itself. It forces the low voltage cell to come into balance with the others.
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Old 05-11-2010, 07:35 PM
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well it seems to be working now.

Im going to charge it and watch the cells. Right now the low voltage cell is actually .09 higher than the rest...

Im going to leave it on slow balance over night....
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Old 05-11-2010, 07:45 PM
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Look at my amp suggestion again it's .1 amp not 1 amp

Point one amp! :-)

===

Had a through the balance plug charger, cost about $8 shipped from Hong Kong (ebay) 12 volt input .8 output. Worked sweet, red LED charging, green LED charged. Gave it to a kid to charge his 3200 lipo.
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Old 05-11-2010, 07:58 PM
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Originally Posted by agarabaghi View Post
well it seems to be working now.

Im going to charge it and watch the cells. Right now the low voltage cell is actually .09 higher than the rest...

Im going to leave it on slow balance over night....
I don't know that I would leave a LiPo on any kind of charge overnight and unsupervised unless you have it out in the middle of your yard or something.
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Old 05-11-2010, 08:06 PM
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Hmm, it is outside, on a ceramic plate, but thats a good point... maybe just for a couple more hours then ill pass out....
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Old 05-12-2010, 01:01 AM
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When you connect the battery to the charger, all its doing is slow balancing.
Not charging.
Got 2 of my 2S' and my 4S back up to snuff so far by doing this.....
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Old 05-12-2010, 01:43 AM
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I tried that before, managed to get the cell up to 3v n above but it heat up n finally kill 2 cells.

So I downgraded from 6c to 4s. Bad idea
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Old 05-12-2010, 05:31 AM
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I left the battery outside, and will put it on the charger tonight again, and see if the cell lost all of its voltage. But from last night it seemed to be charging just fine

hopefully i dont end up in because i will look all and be slightly ....
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Old 05-12-2010, 04:18 PM
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I had a 4S pack go low low on 1 cell after letting it sit for a few days after I had used it on a LONG run before. Iwent to charge it and my charger said low voltage. I checked and one cell was 0.8V. I had always heard throw it away if they drop below 3.0V. I just slow charged the one cell through the balance connector until the voltage in that cell was close to the others(make an adapter out of and old reciever connector from a bad servo or esc). I then balance charged the pack at 0.5A until finished. Pack has been working just fine!!
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