RC-Monster Forums - View Single Post

BrianG · 11.18.2008, 05:03 PM

A 10A supply running at a constant 12v can only supply 120w. Chargers are around 80% efficient, so that is only 96w available for the cells. At 4s 5A, that is reaching the limit (84w). However, at 10A, the supply output voltage is probably dropping. So, if it hits, say 11v, that limits your charge level even more.

And it makes sense that it does this towards the CC/CV threshold since the power requirements are highest then.

That said, I have an old Hyperion EOS7i which displays a different error message ("voltage too high") near the CC/CV threshold when charging lipos at anything above 3.8A. I can charge at whatever current, but when the voltage gets to ~4.0v/cell, I have to drop the charge current to 3.8A. But in my case, it is a charger defect. Works fine at high currents with NiMHs though, so it is indeed a defect. You charger may simply have a similar defect.

	(#5)
BrianG RC-Monster Admin Offline Posts: 14,609 Join Date: Nov 2005 Location: Des Moines, IA	11.18.2008, 05:03 PM A 10A supply running at a constant 12v can only supply 120w. Chargers are around 80% efficient, so that is only 96w available for the cells. At 4s 5A, that is reaching the limit (84w). However, at 10A, the supply output voltage is probably dropping. So, if it hits, say 11v, that limits your charge level even more. And it makes sense that it does this towards the CC/CV threshold since the power requirements are highest then. That said, I have an old Hyperion EOS7i which displays a different error message ("voltage too high") near the CC/CV threshold when charging lipos at anything above 3.8A. I can charge at whatever current, but when the voltage gets to ~4.0v/cell, I have to drop the charge current to 3.8A. But in my case, it is a charger defect. Works fine at high currents with NiMHs though, so it is indeed a defect. You charger may simply have a similar defect.