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Old 02-11-2009, 05:55 PM
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Default Question about Li-Po charging

Can you use a charger that says that it can charge Lithium-Ion batteries to charge Li-Po's ?
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Old 02-11-2009, 06:33 PM
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Yes.
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Old 02-12-2009, 06:21 AM
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You could use any charger actually, as long as they don't pulse/trickle charge (or else you will be charging forever). The only thing is you gotta balance the cells afterwards. Then you can balance the cells once every two weeks after that I believe.

Still new to the whole LiPo scene and going with what I know about them.
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Old 02-12-2009, 06:40 AM
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Originally Posted by HarryN
You could use any charger actually, as long as they don't pulse/trickle charge (or else you will be charging forever). The only thing is you gotta balance the cells afterwards. Then you can balance the cells once every two weeks after that I believe.

Still new to the whole LiPo scene and going with what I know about them.
You mean I can use NiMH/NiCD charger to charge lipo batts? I read somewhere that Lipo charge differently than NiMH so they need different charge software/programme?
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Old 02-12-2009, 06:43 AM
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Originally Posted by dameetz
You mean I can use NiMH/NiCD charger to charge lipo batts? I read somewhere that Lipo charge differently than NiMH so they need different charge software/programme?
you are right. they do charge differently, but it can be done. not reccomended, because it will take forever, and most nimh/nicd chargers trickle then pack, then trickle then pack, and it can cause the lipo to over charge.

lipo overcharge=possible fire
possible fire= not good.
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Old 02-12-2009, 07:45 AM
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Originally Posted by silverhkswrx
you are right. they do charge differently, but it can be done. not reccomended, because it will take forever, and most nimh/nicd chargers trickle then pack, then trickle then pack, and it can cause the lipo to over charge.

lipo overcharge=possible fire
possible fire= not good.
Not all NiMH/NiCD chargers trickle, then charge. There are products like the Duratrash ICE that allows you to change those features. Same with the Triton chargers. The trickle charging is a modular (as in you can select it on or off) function.

But still, you can use any charger to charge your LiPo batteries. It is recommended to use LiPo chargers since they have the features to properly charge/balance your cells. Plus they aren't all that expensive either. A great LiPo charger that has raving reviews is the Thunder Power 610TC. Only $130.00 and it charges, balances, and charges packs for storage like many other chargers out there. But it is very affordable. However, one bit of warning, these chargers can get pretty hot. Make sure you have some moving air on these chargers so they remain cool.
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Old 02-12-2009, 10:11 AM
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The Duratrax Ice you diss has a lipo charging mode, one wonders why someone would use nimh mode to charge lipos.

To answer the OPs question, it is much safer to purchase an inexpensive lipo specific charger than to chance destroying a perfectly good pack, and possibly the property you are charging the batteries in/on/near.

Also, a PSA to everyone - IF YOUR BATTERY COMES WITH DEANS CONNECTORS ON THE PACK, PUT DEANS CONNECTORS ON YOUR CHARGE LEADS, DON'T STUFF ALLIGATOR CLIPS INTO THE END OF THE CONNECTOR AND EXPECT THAT EVERYTHING IS GREAT.

I was at a big race recently and saw the end result of this maneuver...
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Old 02-12-2009, 10:13 AM
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Originally Posted by timmay70
The Duratrax Ice you diss has a lipo charging mode, one wonders why someone would use nimh mode to charge lipos.
It was used as an example.
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Old 02-12-2009, 10:30 AM
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The reason you need to use a LiPo charger has nothing to do with trickle. The reason is that a NiCAD/NIMH charger charges at a constant rate until the battery voltage peaks, then begins to drop off. At that point, the charger will STOP quick charging. Some chargers will then trickle, some won't.

THe problem is that a LiPO pack does NOT reach a peak voltage and then begin to drop, so a NiCAD/NIMH charger will NEVER be able to detect that the LiPO is full. As the LiPO pack reaches full charge, the voltage will continue to climb and the charger will happily keep cranking the juice to it even as the LiPO gets hotter and hotter until a catastrophic failure happens.

A LiPO charger will charge at a constant current until the pack voltage reaches 4.2V per cell, then switch from a constant current to a constant VOLTAGE charge. Once this takes place, the charge current is slowly tapering off. The charger watches the voltage of the pack, and tapers the current off to keep the voltage at 4.2V per cell. Once the current gets to a predetermined level, the charger considers the pack full, and stops.

To answer the original question in this thread...

Yes, you CAN use a LiION charger to charge a LiPO, but you will not get a completely full charge. LiION batteries are charged in the same manneer as LiPO, but the LiIOJN chemistry reches full charge at a slightly lower voltage. Chargers for LiION batteriesd will safely charge a LiPO, but to the slightly lower voltage of a LiION, which is about 90-95% full for a LiPO.

You wouldn't want to charge a LiION pack with a LiPO charger, the higher voltage of the LiPO charge would overcharge a LiION. YOu might get away with it, but you'd be overcharging and reducing the life of the pack. You'd also be inviting the possibility of a thremal runaway at some point. It probably wouldnt' go that far, but the possibility is there.
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Old 02-15-2009, 08:14 PM
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Originally Posted by Trips
The reason you need to use a LiPo charger has nothing to do with trickle. The reason is that a NiCAD/NIMH charger charges at a constant rate until the battery voltage peaks, then begins to drop off. At that point, the charger will STOP quick charging. Some chargers will then trickle, some won't.

THe problem is that a LiPO pack does NOT reach a peak voltage and then begin to drop, so a NiCAD/NIMH charger will NEVER be able to detect that the LiPO is full. As the LiPO pack reaches full charge, the voltage will continue to climb and the charger will happily keep cranking the juice to it even as the LiPO gets hotter and hotter until a catastrophic failure happens.

A LiPO charger will charge at a constant current until the pack voltage reaches 4.2V per cell, then switch from a constant current to a constant VOLTAGE charge. Once this takes place, the charge current is slowly tapering off. The charger watches the voltage of the pack, and tapers the current off to keep the voltage at 4.2V per cell. Once the current gets to a predetermined level, the charger considers the pack full, and stops.

To answer the original question in this thread...

Yes, you CAN use a LiION charger to charge a LiPO, but you will not get a completely full charge. LiION batteries are charged in the same manneer as LiPO, but the LiIOJN chemistry reches full charge at a slightly lower voltage. Chargers for LiION batteriesd will safely charge a LiPO, but to the slightly lower voltage of a LiION, which is about 90-95% full for a LiPO.

You wouldn't want to charge a LiION pack with a LiPO charger, the higher voltage of the LiPO charge would overcharge a LiION. YOu might get away with it, but you'd be overcharging and reducing the life of the pack. You'd also be inviting the possibility of a thremal runaway at some point. It probably wouldnt' go that far, but the possibility is there.
Thanks for the info.
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Old 02-15-2009, 09:50 PM
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Originally Posted by THE DOCTOR
Thanks for the info.
And it only took 9 posts to get the answer you wanted. Not too shabby.
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