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Old 12-03-2008, 07:39 PM   #1
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Default Turbo 35GFX Lipo Balancing

This was in the Manual Addendum:
The charge state of each cell in a LiPo pack should be periodically balanced by setting up the GFX for a single cell pack (1S) and running a low current discharge cycle on each individual cell in the pack. This will equalize the charge state of each cell and when you run the charge cycle on the pack,
it will be back in balance again.

I think this means there is no need for an external balancer.

Is there anyone that has done this and is it as good as an external balancer?
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Old 12-03-2008, 08:15 PM   #2
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whoooaaaaaaa,
That addendum is not the right way to balance a lipo pack. Are you sure you typed in the addendum correctly?

As lipos age, their state of charge shifts and their capacities change as well. In a 2 cell pack, one cell may be loosing capacity faster than the other - which is the point of balancing.

For example if one cell is 5000mah and the other is 4800mah. If you discharge both of them to 0% charge and charge as a pack - the 5000 gets undercharged and the 4800 gets overcharged. It's important the the individual cell voltages are close to identical at the END of charge not the beginning.

If you cells start deviating and if you discharge each cell individually and charge them up again - you will have an unbalanced pack.

The correct way to balance with the GFX is to CHARGE each cell individually.
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Old 12-03-2008, 09:40 PM   #3
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Even if you tried to balance them by charging one at a time, wouldn't one cell begin to self-discharge while you were charging the other cell? I would think the only true way to balance the pack would be to have 2 turbo 35s hooked to the battery... one for each cell. Otherwise, you'd have to use a regular lipo balancer that charges both cells individually at the same time.
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Old 12-03-2008, 09:56 PM   #4
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Self discharging? Even if you lose a couple of mah in the 40 minutes it takes to charge the other cell it will not make a difference. The point of balance charging is not to OVERCHARGE the individual cells.
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Old 12-03-2008, 11:37 PM   #5
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Quote:
Originally Posted by Serzoni View Post
Even if you tried to balance them by charging one at a time, wouldn't one cell begin to self-discharge while you were charging the other cell? I would think the only true way to balance the pack would be to have 2 turbo 35s hooked to the battery... one for each cell. Otherwise, you'd have to use a regular lipo balancer that charges both cells individually at the same time.

no,
the amount of self discharge in 1 hour is negligible.
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Old 12-04-2008, 12:39 AM   #6
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Linger is completely correct. This is why you should never use a balancer alone in discharge mode as it will create what Linger explained. If someone wants to check the balance of there pack you need to check it when it's fully charged. You can do this by putting a voltmeter on the balance connector pins. On the SMC packs the Red wire equals + of cell 1 and the middle Black wire equald negative of cell 1. Then the middle Black wire becomes + of cell 2 and the outer wire becomes negative of cell 2.

Linger can tell you how off the voltage should be for it to be considered out of balance as I have never asked this question before so I'm not sure. I would think .02 should be o.k. but I maybe wrong.
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