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Is there anything that could cause the battery's "cycles count" in the Power section of System Information app to report number of charge cycles greater than the actual number?

I ask because the number of charge cycles displayed for my MacBook Air is greater than the number of days I have owned the computer, and I certainly have not used it every day, nor charged and then used the battery more than once a day. What could cause the number to be so high?

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Just to be clear, you never plug and unplug throughout the day, it's plugged in at most one time each day? – Kyle Cronin Mar 24 '12 at 0:37
Generally speaking (I can't claim there is never an exception), I use the computer away from the power cord for (at most) one stretch in a day; the rest of the time, if I use it, it is plugged in to the wall. – Daniel Mar 24 '12 at 0:41
up vote 3 down vote accepted

A faulty sensor could do it. Apple says:

"A charge cycle means using all of the battery’s power, but that doesn’t necessarily mean a single charge. For instance, you could use your notebook for an hour or more one day, using half its power, and then recharge it fully. If you did the same thing the next day, it would count as one charge cycle, not two, so it may take several days to complete a cycle."

Looks like a good case for a visit to the Genius Bar, and perhaps having your battery replaced. I agree it does not seem at all plausible that your cycle count is higher than the days you have owned it.

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It's easily possible the number of cycles exceeds the number of days owned, just in this case Daniel says it's not. – Kyle Cronin Mar 24 '12 at 0:32
OK, you could try hard and make it so. But not in average usage. – Adam Eberbach Mar 24 '12 at 0:34
I would guess that last week when I was working on the MacBook Air I averaged 2 cycles/day. Worked all morning. Charged at lunch. Unplugged when charge was full and moved to porch. Worked into the evening. Charged over night. Wasn't trying at all. ;) – jaberg Mar 24 '12 at 1:57

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