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BrianG
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01.27.2009, 08:33 PM

Quote:
Originally Posted by pedeboi364 View Post
CV? CC? does not compute...

Looks pretty risky. Here's the link: http://www.losi.com/Products/Feature...rodId=LOSB9607

Hopefully i can get that charger from lincpimp and a balancer (anyone have a balancer for sale??)
Sorry. CC=Constant Current. CV=Constant Voltage.

Ready for the technical explanation? Well, heeere goes:

Most NiMH chargers use CC mode only. When the battery is fully charged, the charge voltage hits its peak and then starts to drop again. This drop is the "delta" value, and the charger knows to stop charging. Lipos do not behave this way.

When lipos charge, the charge current is kept steady and the voltage slowly climbs. This is the CC stage, and is exactly like NiMH charging. However, when the voltage hits 4.2v per cell, the charger then keep the charge voltage constant (the CV stage), and the current slowly falls to a preset value, usually something like 1/10 of the initial set charge current. At this point charging stops.

This device simply monitors the cell voltage until it hits the 4.2v/cell threshold. When this happens, the devices interrupts the charge current. This looks like an open circuit to the charger and it stops the charge (usually with an error, but the error is good in this case). As you can see, only the CC stage is done, so you lose whatever capacity that would have been put in during the CV stage. Usually, the amount charged during the CV stage is not very much, probably like 5-10%. But that means you are only putting back between 4500mAh and 4750mAh into a 5000mAh battery.

It's a cheap way to get a lipo charger if you don't care about that loss of capacity.
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