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Old Dec 30, 2011, 02:10 PM
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United States, PA, Dover
Joined Aug 2011
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How much time would .5 amps knock of my charging time.

I have a 3-cell 2200mah 30c eflite lipo that came with a 1.8 amp charger and i only have the aligator clips for it. So i use the hobby zone charger to charge from the house wall which is for a 3-cell 1300mah 15c lipo which charges at 1.3 amp. So my question is if im charging the 3-cell 2200mah 30c from the wall at 1.3 amps and it takes an hour to charge, About how much time would i knock off if i charge the 3-cell 2200mah 30c lipo with the 1.8 amp charger with aligator clips to the car?
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Old Dec 30, 2011, 02:41 PM
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United States, CA, Westminster
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Quote:
Originally Posted by Stoned doggie View Post
So my question is if im charging the 3-cell 2200mah 30c from the wall at 1.3 amps and it takes an hour to charge, About how much time would i knock off if i charge the 3-cell 2200mah 30c lipo with the 1.8 amp charger with aligator clips to the car?
Seems like it would be 38% less time.

It should not matter if it is from the wall or your car the charge amount should stay the same.
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Old Dec 30, 2011, 03:35 PM
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If it's taking 1 hour to charge at 1.3A, that's possibly only 50 minutes at full 1.3A rate followed by 10 minutes at reducing amps, constant voltage, rate. So your charger may have only put about 1100mAh into the pack (i.e. the pack was only half discharged). To do the same thing at 1.8A would take about 33 minutes full rate plus the same 10-minute constant voltage phase.

As TheWoodCrafter has said, it doesn't matter where the charger is getting its power from. But the battery's condition, and the way the chargers are designed, will affect my assumption about how long it takes for the reduced-amp constant-voltage phase of the charging and, thus, the calculations for total charge time.
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Old Dec 30, 2011, 03:40 PM
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Joined Oct 2000
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Probably much less than you think. The constant current phase will last longer with the lower current so in the end, the difference isn't that great.
See the note on "Fast Charging" in this article.
http://sites.google.com/site/tjinguy...-chargers-work
From Battery University -
Increasing the charge current does not hasten the full-charge state by much. Although the battery reaches the voltage peak quicker with a fast charge, the saturation charge will take longer accordingly. The amount of charge current applied simply alters the time required for each stage; Stage 1 will be shorter but the saturation Stage 2 will take longer. A high current charge will, however, quickly fill the battery to about 70 percent.

Fast charging will be faster but not linear to the charge current.

The advantage of fast charging is much greater if the user is happy at cutting off the charge at 90-95%. The CC phase quickly takes it up to 70% and then cut the CV stage by accepting a lower charge %.
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Last edited by hoppy; Dec 30, 2011 at 03:55 PM.
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