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BrianG · 04.08.2008, 02:22 PM

3.1v/cell with no load is too low. Once disconnected from the ESC for about 20 minutes, the cell voltage should drift back up to around 3.5v/cell. If you can, increase the LVC by to 3.1-3.2v/cell. Assuming the LVC is adjustable of course. The LVC will trip sooner, but the cells will rebound to a more healthy level. You won't get much reduction in runtime (might not be even noticeable) since lipo voltage generally drops off quickly near the LVC point.

Balancers only bleed off cells that have a higher voltage than the others. So, unless cell(s) were being actively balanced the whole time, a balancer won't eat up any of the charge capacity.

In case I wasn't clear before; let's say a balancer discharges high cells at 200mA. If you are charging at, say, 4A, the high cells will only get 3.8A (4A-200mA), while the low cells get the full 4A. So, if the balancer was actively balancing during the whole charge cycle, the high cells will only get 4400mAh out of the 4600mAh the charge display shows. If cells were actively balancing for half the charge cycle, they would get 4500mAh out of the displayed 4600mAh. Again, this is assuming a 200mA balancer discharge rate - if it's higher (like 400mA), these numbers will be different. I hope that all made sense.

NiMH cells don't like excessive heat, and 160-185*F is too hot IMO and probably reduced their life. It doesn't help that they have quite a bit of cycles on them.

	(#4)
BrianG RC-Monster Admin Offline Posts: 14,609 Join Date: Nov 2005 Location: Des Moines, IA	04.08.2008, 02:22 PM 3.1v/cell with no load is too low. Once disconnected from the ESC for about 20 minutes, the cell voltage should drift back up to around 3.5v/cell. If you can, increase the LVC by to 3.1-3.2v/cell. Assuming the LVC is adjustable of course. The LVC will trip sooner, but the cells will rebound to a more healthy level. You won't get much reduction in runtime (might not be even noticeable) since lipo voltage generally drops off quickly near the LVC point. Balancers only bleed off cells that have a higher voltage than the others. So, unless cell(s) were being actively balanced the whole time, a balancer won't eat up any of the charge capacity. In case I wasn't clear before; let's say a balancer discharges high cells at 200mA. If you are charging at, say, 4A, the high cells will only get 3.8A (4A-200mA), while the low cells get the full 4A. So, if the balancer was actively balancing during the whole charge cycle, the high cells will only get 4400mAh out of the 4600mAh the charge display shows. If cells were actively balancing for half the charge cycle, they would get 4500mAh out of the displayed 4600mAh. Again, this is assuming a 200mA balancer discharge rate - if it's higher (like 400mA), these numbers will be different. I hope that all made sense. NiMH cells don't like excessive heat, and 160-185*F is too hot IMO and probably reduced their life. It doesn't help that they have quite a bit of cycles on them.