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Any good to constantly keep top charging LiPo's?

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Old 04-07-2011, 04:39 AM
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tcraftpo
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Default Any good to constantly keep top charging LiPo's?

Due to many factors beyond my control, I seem to be constantly top charging my LiPo's to get ready to go flying, then for some reason or another I can't go. These are big 5S, 5000 mAh batteries so charging at the field will usually take too long. My question is: Is there any potential issue of constantly top charging LiPo's, then letting them sit for a week or so, then doing it again?

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Pat
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Old 04-07-2011, 01:49 PM
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Default RE: Any good to constantly keep top charging LiPo's?

Hi Pat -

I don't think you'll damage the batteries as long as you are using a good quality charger. However, you may find that you don't really need to top off lipos if they are only sitting unused for a week. Lipos have a very low self-discharge rate. Check the voltage of a battery that has been sitting for a week. If it measures close to 4.2V per cell (21V for a 5S pack), it is ready to fly without topping off.

- Jeff
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Old 04-09-2011, 07:49 AM
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Default RE: Any good to constantly keep top charging LiPo's?

Thanks Jeff, I appreciate and will use the info. in the future.

Pat
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Old 05-24-2011, 12:42 PM
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Default RE: Any good to constantly keep top charging LiPo's?

I heard that if you keep topping them off, eventually they go bad, they need to be kept below a certain voltage to be stored and then used at that voltage before charging again, apparently, every charge put on the battery takes away one life. They have no memory but are sensitive to over charging and over use.  I asked about cycling the Lipos, and was told in uncertain terms, do it once, after that you will kill the battery. I have a charger for NiMH that will cycle the batteries, and a car charger that will do the same, it puts a draw on the battery so it draws down to a set level and then gets recharged, a sort of conditioning for them. Lipos cant be done like that.
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