Why did a 5Ah battery I used for 15+ minutes mowing the lawn indicate that it was fully charger when I attempted to charge it?

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I have 2 5Ah batteries that I use for mowing and leaf blowing. To finish my mowing, I swapped to 2nd battery for last 15 or so minutes. When I used the quick charger, it showed 100% and refused to charge. Therefore, I used my blower for 2 to 3 minutes and then it started charging.

Is this normal?

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Howard Halstead

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Posted 2 years ago

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Lehigh Lawn Pros

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Hi Howard,
I've had the same thing happen a number of times with the 5.0Ah batteries.
If I only use them for a short period of time, they won't charge on the standard chargers either.
It seems like they need to be discharged to a certain level before the chargers will charge them.

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Ken, Champion

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That seems to be true of a lot of “smart” lithium-ion batteries. I can use one of my drone batteries for three or four minutes (which have a 25 minute runtime) and the charger will still show it as fully charged. I have to deplete it a bit more before I can charge it.