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Old 02-04-2009, 10:57 AM   #16
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If you don't have a fully "empty" Lipo (they never are) - you try to force in the full charge amount of 6500mAh you may overcharge it.

If you ran the LiPo for a while and it had a 1/2 charge in it - then hooked it up trying to do a 5A 5000mAh charge - you'd surely puff it up and over charge it unless the charger is knowledgeable about LiPo constraints.

If the charger will sense the proper voltage peak for charging LiPo - then maybe it'll work out.
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Old 02-04-2009, 11:14 AM   #17
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Originally Posted by RyyRyy View Post
Trickle is way different... any current up to date Lipo specific charger does not have trickle on it...

Do what you please but I am confident in saying that it is not the healthiest thing you can do for your pack... Many people do not realize the danger that these batteries can bring and end up treating them like toys...

I've been using lipos even before they were brought to R/C cars... so believe me when I say i Know a bit about them...

Don't believe me? then take the yellow instruction sheet of any Thunder Power pack and skim through it, you'll see something there that says the same thing I wrote in my first post...
Thats not what I meant by trickle, I meant if someone tries to charge a lipo at say .5 amp and for some reason the charger does not limit itself at the 8.40 properly and it goes over. All of the chargers I've used don't have this problem I was just speculating it was to prevent some chargers from accidentally over charging...

Charging a 6Ah battery at 5A is not going to hurt it, find me any hard evidence that says otherwise... 1C is typically the maximum stated and some manufacturers on their battery state a minimum as well from what I have seen usually around 2A (such as the Team Orion batteries). The CC phase of charging is usually not that long anyway before it must reduce amperage to keep voltage under 8.40v anyway... So that whole ending CV phase the charge current is ALWAYS less than 1C that must be bad for your battery too

And to jmcvicker the chargers use a CC/CV charge method, they don't care how much Ah they put in to the battery at all, it relies totally on voltage (with the exception of the safety cut off some chargers have if it breaks an artificial threshold and it thinks it may have put in too much). You will NEVER overcharge a lipo pack using a proper lipo charger...
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Old 02-04-2009, 12:52 PM   #18
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Originally Posted by tazeat View Post
Thats not what I meant by trickle, I meant if someone tries to charge a lipo at say .5 amp and for some reason the charger does not limit itself at the 8.40 properly and it goes over. All of the chargers I've used don't have this problem I was just speculating it was to prevent some chargers from accidentally over charging...

Charging a 6Ah battery at 5A is not going to hurt it, find me any hard evidence that says otherwise... 1C is typically the maximum stated and some manufacturers on their battery state a minimum as well from what I have seen usually around 2A (such as the Team Orion batteries). The CC phase of charging is usually not that long anyway before it must reduce amperage to keep voltage under 8.40v anyway... So that whole ending CV phase the charge current is ALWAYS less than 1C that must be bad for your battery too

And to jmcvicker the chargers use a CC/CV charge method, they don't care how much Ah they put in to the battery at all, it relies totally on voltage (with the exception of the safety cut off some chargers have if it breaks an artificial threshold and it thinks it may have put in too much). You will NEVER overcharge a lipo pack using a proper lipo charger...
forget everything else that he said.
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Old 02-04-2009, 05:57 PM   #19
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Ok your right I shouldn't have made that statement a few assumptions are made there.

First I'm defining overcharging as having a cell over 4.20v.

Second I'm assuming the charging hardware is in good working order, set to lipo mode, and the correct number of cells in series are set (2S in this discussion, meaning a 8.40v CV finish).

Third I'm assuming your lipo battery is in good working order, balanced, and not damaged.

In this scenerio you could take a fully charged 1200mah cell, hook it up to a hyperion charger, set it to a 10A charge rate or a 10000mah capacity battery hit charge and either 1 of 2 things will happen:
1) It will see the 8.40v and say full
2) It will see slightly less (say for discussion 8.30v) and charge very slowly (NOT 10A CC charging!!!) keeping the voltage under 8.40v aka CV charging then say full a few seconds later when the pack is full. It won't explode.

It will NOT try and charge all 10000mah in to the battery. That's stupid. That's like saying when you run a 5000mah battery for 2 minutes throw it back on the charger it wil try to put 5000mah back in to it... Of course not, it will only put back in what it takes to get it back to full.

Come on this isn't rocket science, just keep your cells under 4.20v. Don't let them fall below 3.00v. Don't charge faster than what it says on the label (1C typically). Make sure you pick lipo with the correct number of cells in series on the charger. And you should not have any problems charging.

I'm not saying you can be careless, use your lipo sack or ammo box whatever, cells do go bad, but not because of the charger.
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Old 02-04-2009, 07:35 PM   #20
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ya, that's all I was wondering..

So after all these comments my charger is FINE to charge a 8000mah pack.. All I need to do is set the same settings as I would for my 5000mah 2s 7.4v pack and let it charge.. It will just take a few more minutes..
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Old 02-04-2009, 07:51 PM   #21
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ya, that's all I was wondering..

So after all these comments my charger is FINE to charge a 8000mah pack.. All I need to do is set the same settings as I would for my 5000mah 2s 7.4v pack and let it charge.. It will just take a few more minutes..



You are correct. Set the charger to its max amp rate and select the proper number of cells and you will be good to go.
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