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Young Spade

macrumors 68020
Original poster
Mar 31, 2011
2,156
3
Tallahassee, Florida
For the past 3 days or so, the health of my battery went from the mid-high 80s down to around 50%, causing me to drastically limit the amount of time I could use while off the charger;I could get around 2 hours max if I did light things like surf the web or compose documents.

I recently bought a replacement battery so it should get here soon, however just today I pulled it off the charger and the health went back up to 85 percent and I'm getting around 3.5 hours off the charger.

I'm glad the new battery is coming, however do you have any idea why it would jump around like this? I turned it off multiple times during this whole charade along with sleeping (which I do regularly) so I have no idea why this is happening.

41 month old with 546 cycles.

08 BlackBook. Thanks :)
 
Reset the SMC and calibrate your battery to make sure your readings are accurate. Also, be aware your battery is designed to retain up to 80% of its original capacity up to 300 cycles. you're well beyond that. This should answer most, if not all, of your battery questions:
 
For the past 3 days or so, the health of my battery went from the mid-high 80s down to around 50%, causing me to drastically limit the amount of time I could use while off the charger;I could get around 2 hours max if I did light things like surf the web or compose documents.

I recently bought a replacement battery so it should get here soon, however just today I pulled it off the charger and the health went back up to 85 percent and I'm getting around 3.5 hours off the charger.

I'm glad the new battery is coming, however do you have any idea why it would jump around like this? I turned it off multiple times during this whole charade along with sleeping (which I do regularly) so I have no idea why this is happening.

41 month old with 546 cycles.

08 BlackBook. Thanks :)

With a battery that old you need to condition at least once a month. I have found that coconut battery give a quick insight to where battery health.
 
546 cycles is up there, I would not be surprised with strange experiences with such a high cycle count. Definitely condition your battery if possible though Complete charge to 100% if possible, complete usage to as low as possible. Repeat this cycle again, never connecting the power in between.
 
546 cycles is up there, I would not be surprised with strange experiences with such a high cycle count. Definitely condition your battery if possible though Complete charge to 100% if possible, complete usage to as low as possible. Repeat this cycle again, never connecting the power in between.
That's not how you "condition" a Mac battery. Read the CALIBRATION section of the FAQ I posted.
 
546 cycles is up there, I would not be surprised with strange experiences with such a high cycle count. Definitely condition your battery if possible though Complete charge to 100% if possible, complete usage to as low as possible. Repeat this cycle again, never connecting the power in between.

Uh.. yea that's not how you calibrate the battery... and I calibrate it monthly already... but thanks for that though.
 
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