RC-Monster Forums - View Single Post - Damnit, the Lipo battery industry needs better standards!

BrianG · 11.10.2009, 04:03 PM

Somewhat. I balance charge as well, but if there is a situation where the balancer cannot equalize the cells before the CC/CV threshold, one or more cells could go over the 4.2v limit. Of course, this only applies to non-balancing chargers.

I'm not sure how the Triton works internally, but most chargers apply a CC charge until the voltage hits 4.2v/cell, then switches to CV mode and the current dwindles down to a set value before it shuts off. Actually, to be accurate, most chargers are always doing a CC charge, but at the "CV" phase, they just monitor the voltage and make constant changes to the charge current. But that's just a technicality.

As far as the LVC point goes, I take it case by case. I like to see 3.5-3.6v/cell open-circuit voltage once the load is removed for about 10-15 minutes. All batteries will exhibit some voltage "drift" back up once you remove the load. How much they drift back up depends on their design. Cells with higher resistances will drop voltage under load more, and will drift back up more, so I set the LVC for 3.2v/cell. If you have a cell with extremely low resistance, there is much less drift once the load is removed. So, to get a decent resting voltage, the LVC needs to be set higher to compensate. The same approximate mAh is used, it's just a matter of understanding how batteries work and tailoring care and maintenance accordingly.

The only pack I have every puffed was a MA pack, but no surprise there. It was being used in a setup that it should easily have handled. Oh yeah, I did puff another higher quality pack, but that was because it was a 2p pack and one of the cell pairs came apart causing one cell to handle the entire load.

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BrianG RC-Monster Admin Offline Posts: 14,609 Join Date: Nov 2005 Location: Des Moines, IA	11.10.2009, 04:03 PM Somewhat. I balance charge as well, but if there is a situation where the balancer cannot equalize the cells before the CC/CV threshold, one or more cells could go over the 4.2v limit. Of course, this only applies to non-balancing chargers. I'm not sure how the Triton works internally, but most chargers apply a CC charge until the voltage hits 4.2v/cell, then switches to CV mode and the current dwindles down to a set value before it shuts off. Actually, to be accurate, most chargers are always doing a CC charge, but at the "CV" phase, they just monitor the voltage and make constant changes to the charge current. But that's just a technicality. As far as the LVC point goes, I take it case by case. I like to see 3.5-3.6v/cell open-circuit voltage once the load is removed for about 10-15 minutes. All batteries will exhibit some voltage "drift" back up once you remove the load. How much they drift back up depends on their design. Cells with higher resistances will drop voltage under load more, and will drift back up more, so I set the LVC for 3.2v/cell. If you have a cell with extremely low resistance, there is much less drift once the load is removed. So, to get a decent resting voltage, the LVC needs to be set higher to compensate. The same approximate mAh is used, it's just a matter of understanding how batteries work and tailoring care and maintenance accordingly. The only pack I have every puffed was a MA pack, but no surprise there. It was being used in a setup that it should easily have handled. Oh yeah, I did puff another higher quality pack, but that was because it was a 2p pack and one of the cell pairs came apart causing one cell to handle the entire load.