Great Plains Electrifly Lipo batteries and balancing charger Issues

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ozwald

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Cottonwood, AZ.
Hey all. Picked up some 2s 7.4v 250ma and 600ma batteries and a Great Planes 2s balancing charger. Have been tinkering with setting them up to operate my GPS tracker and deployment electronics. My tracker didn't power up this morning and I found that battery had fallen to below 4 volts. Went to recharge and found that the lights flashed error. Checked the other three batteries and they all showed charged. Sent an email to hobbico support and when I got that done I came back and retried the first battery just for grins and it showed the same error. Checked the other three and they all showed error. WTF Is anyone familiar with this specific charger? Great Planes M# GPMM3321. I hope I didn't buy junk trying to save a few pennies?
 
That sounds like the charger is doing what it's supposed to..
The first thing any balance lipo charger does is check voltage..
If it is out of spec for what it should be it will not begin charging,, it'll just show "Error"...
A single lipo cell should be ( from memory, don't hang me if I'm a tenth off )
about 3.7 volts... That cell will be about 4.0 to 4.2 fully charged...
A 2s battery will be about 7.4 volts,,, about 8 to 8.4 fully charged...
What you have said is you have a 2s battery with a dead cell..
This is the reason I use a better quality charger,, not crazy expensive..
I take a battery like this and tell the charger it is Nimh,, the charger will start chatrging..
I leave it on for a short time at a slow charge rate and WATCH it while I'm doing this..
I stop and let it rest,, then do it again for a bit..
Soon the battery will show just enough voltage for the charger to start when it's set correctly as a 2s lipo ( or however many cells it is )..
I charge the battery on balance for a cycle.. Then put the charger on cycle,, I set the charger to be gentile with the battery,,
it will discharge it to say, 40%,, then a few minutes cool down,, then charge it to 97 or 98% then a cool down ,, then do the whole thing again,,
after this is done 3 cycles of discharge and then charge the battery should read good.. Monitor it,, if it keeps a charge and works well,, all good..
If not dispose of it properly............

Teddy
 
+3 to Teddy .. have had to trick my Turnigy charger before , only takes a minute then set charger for Lipo again
 
Thanks for the reply Teddy. The charger I have is a plug in the AC or car adapter and it has a 3 pin balance plug. That's it, no user settings. This stuff is new, never flown, and only used for testing. As I stated all of the batteries except the one that was 4 volts or less were charged and the 2S 600mah batteries were never hooked up to power anything. The funny thing is once I noticed the battery was low, I attempted to charge it. Got an error but checked the other three and they went through precharge test and charged. Now none of them do anything but code out? First use of lipos and considering the issues I'm going back to nine volt batteries like I've used since I started. Never had a problem with those. Kinda seems stupid that a rechargeable battery that discharges totally is junk after that?
 
Thanks for the reply Teddy. The charger I have is a plug in the AC or car adapter and it has a 3 pin balance plug. That's it, no user settings. This stuff is new, never flown, and only used for testing. As I stated all of the batteries except the one that was 4 volts or less were charged and the 2S 600mah batteries were never hooked up to power anything. The funny thing is once I noticed the battery was low, I attempted to charge it. Got an error but checked the other three and they went through precharge test and charged. Now none of them do anything but code out? First use of lipos and considering the issues I'm going back to nine volt batteries like I've used since I started. Never had a problem with those. Kinda seems stupid that a rechargeable battery that discharges totally is junk after that?

please post picture

I edited , from pictures appears only way to hook for charging , charger looks to lack features
 
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Posted on behalf of Ozwald

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Oz,,
Everything you're saying makes perfect sense...
I am really sorry I didn't make this more clear..
The one thing a lipo just will not tolerate at all is being over discharged...
The charger you received is only capable of doing one single thing,,
balance charge a 2s lipo battery..
It seems to be doing everything it is supposed to do...
All of the batteries you have received are no good...
If the battery is good the charger will charge it and you'll be good to go...
But the first thing the charger does when you plug it in and start it is check the battery,,
The charger through the balance plug has access to each cell individually..
If either cell shows any value out of spec ( bad ) the charger won't start,, it'll just show error...
Lipo's are so much better then alkalines Oz,, I hate to see this discourage you from getting into them..
I wish we lived closer / flew at the same field,, lol..
Just get the batteries exchanged,, tell them they gave you bad batteries,,
or if you want just return them and order the charger I showed you...
If you do I'll show you lipo batteries that cost just a few dollars each and will fly your rockets for years..
It really is a good investment...

Teddy
 
Oz,

I agree with Teddy. The Smart Charger I use requires both the balance leads and the power leads be connected, because it supports a wide range of batteries. Your charger is purpose built and will only work with a narrow range of batteries.

While it may be possible to revive them, I don't understand how or why they would self-discharge below their acceptable limit.

As I mentioned in my PM to you, I had success switching to lipo batteries, and I think it's because I invested in a quality smart charger like the others have posted.
 
Oz,

I agree with Teddy. The Smart Charger I use requires both the balance leads and the power leads be connected, because it supports a wide range of batteries. Your charger is purpose built and will only work with a narrow range of batteries.

While it may be possible to revive them, I don't understand how or why they would self-discharge below their acceptable limit.

As I mentioned in my PM to you, I had success switching to lipo batteries, and I think it's because I invested in a quality smart charger like the others have posted.

+1......

The charger is everything...
But these in general are still a great investment...

Teddy
 
Thanks for the great info and advice guys. Today is a much brighter day for me and I will wait to talk with the tech hopefully tomorrow. I honestly think that the batteries are fine and the charger is defective. I can't see 4 seperate batteries being bad but ya never know? I will definately get a smarter charger :)
 
Hey all. Finally got all of this sorted out. After numerous conversations with tech support they diagnosed a bad charger and shipped me a new one as well as a new 2S to replace the one that went low. Received the new charger and all batteries went to error like the first charger. I told them I wanted my money back and they did so quickly. So here I am weeks later still dicking around with Lipo concerns and curious what to do with this pile of items I've collected :)
 
save for $ for Hobbyking when they have back in stock you will be happy :)

I have your email , will email my charger book and pictures later today of Turnigy items
 
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