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zeropointbug · 02:27 PM

Well, you can't really predict the 'full' mark' on a lipo pack if you were to increase the charge voltage, as it would just keep going until it permanently damaged itself.

A123's are different, the chemistry only has a limited amount of lithium ions in the cell, so once it nears the end of charge, the voltage rises quite rapidly... so you would be able to see a 'sign' of being full when using strictly CC phase. Life chemistry is better in this way, as it is safer for charging. This, I suppose you could call the traditional 'peaking' method as used with batteries like NiMH, but not quite the same outcome, or repercussions if things go wrong.

Lipo cells have, IIRC, over twice as the amount of lithium ions that are necessary, so you cannot see a voltage 'spike' at end of charge, which makes things dangerous.

I have found, when charging an A123 cell, you can use 3.9v/cell @ 10 amps using only CC phase and get, I would say, at least 95% capacity into the cell.

	(#12)
zeropointbug Z-Pinch racer Offline Posts: 3,141 Join Date: Nov 2006 Location: SK, Canada	08.16.2009, 02:26 PM Well, you can't really predict the 'full' mark' on a lipo pack if you were to increase the charge voltage, as it would just keep going until it permanently damaged itself. A123's are different, the chemistry only has a limited amount of lithium ions in the cell, so once it nears the end of charge, the voltage rises quite rapidly... so you would be able to see a 'sign' of being full when using strictly CC phase. Life chemistry is better in this way, as it is safer for charging. This, I suppose you could call the traditional 'peaking' method as used with batteries like NiMH, but not quite the same outcome, or repercussions if things go wrong. Lipo cells have, IIRC, over twice as the amount of lithium ions that are necessary, so you cannot see a voltage 'spike' at end of charge, which makes things dangerous. I have found, when charging an A123 cell, you can use 3.9v/cell @ 10 amps using only CC phase and get, I would say, at least 95% capacity into the cell. “The modern astrophysical concept that ascribes the sun’s energy to thermonuclear reactions deep in the solar interior is contradicted by nearly every observable aspect of the sun.” —Ralph E. Juergens Last edited by zeropointbug; 08.16.2009 at 02:27 PM.