I was reading this other topic and it said something like "battery health at 92% after 17 cycles." What does that mean? I looked at my iStat and it said mine is 99%health after 3 cycles. Is that good or bad?? How long do batteries usually last??
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Battery question for the MacBook (late '09)
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That is good. 
Some people on this forum might try to claim otherwise, but there's no reason a battery can't last several thousand cycles (albeit being in bad condition at the end). After a couple of hundred cycles you'll start to notice the battery life being slightly shorter, but there shouldn't be any other problems.
Some people on this forum might try to claim otherwise, but there's no reason a battery can't last several thousand cycles (albeit being in bad condition at the end). After a couple of hundred cycles you'll start to notice the battery life being slightly shorter, but there shouldn't be any other problems.
There almost bi-daily threads about this:
http://www.google.com/cse?cx=011016...e:forums.macrumors.com&hl=en&as_qdr=all&meta=
Health is percent of original maximum capacity.
If original capacity is 12000mAh and health is at 95%, then the current maximum battery capacity 11400mAh.
Cycles are the complete discharge from 100% capacity to 0% capacity (not to be confused with maximum capacity, as 100% can be 12000mAh or 1200mAh after many, many cycles and 10% health).
If you discharge (use the computer on battery), then one cycle can be added up by having five discharges from 100% to 80%, or two discharges from 100% to 50%, or one from 100% to 37% and one from 100% to 63%, and so on.
There is also www.apple.com/batteries .
http://www.google.com/cse?cx=011016...e:forums.macrumors.com&hl=en&as_qdr=all&meta=
Health is percent of original maximum capacity.
If original capacity is 12000mAh and health is at 95%, then the current maximum battery capacity 11400mAh.
Cycles are the complete discharge from 100% capacity to 0% capacity (not to be confused with maximum capacity, as 100% can be 12000mAh or 1200mAh after many, many cycles and 10% health).
If you discharge (use the computer on battery), then one cycle can be added up by having five discharges from 100% to 80%, or two discharges from 100% to 50%, or one from 100% to 37% and one from 100% to 63%, and so on.
There is also www.apple.com/batteries .
Consider yourself lucky. I recently took my 15" MBP to Apple Store as the laptop was showing that my battery needs to be serviced after just barely under 50 cycles. Fortunately, I have AppleCare and so after doing some testing they just gave me a new battery.
Good luck!