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dr.devious

macrumors regular
Original poster
Nov 30, 2008
206
56
Truckee Meadows, NV
Tonight I accidently left my MacBook on and it some how ran down to 1% and shut off. I immediately plugged it back in and began charging back up. Have done any damage to the battery or it's capacity?
 
Nope, if anything it will start showing MORE accurate information as far as time remaining and max capacity goes than it did before. How else do you think battery calibrations work? :D
 
you can't run the battery dry. it has protection to keep the cells from fully discharging. so even though it says 1% that only means it has 1% left till the battery voltage is low enough to trigger the cut off. this is what I really like about Li ion cells.
but fully draining the cells if you could would not be a good thing.
 
Just don't let it happen too often. It's actually not recommended to continually let it run down then charge it back up, unless you are doing your monthly Calibration (but there are additional steps to that process).
 
you can't run the battery dry. it has protection to keep the cells from fully discharging. so even though it says 1% that only means it has 1% left till the battery voltage is low enough to trigger the cut off. this is what I really like about Li ion cells.
but fully draining the cells if you could would not be a good thing.

If you leave it for months they can lose their residual charge and die.
 
It is not something I would plan on letting happen regularly, but at the same time is also part of the battery calibration process you should be doing every so often - every six months or so depending on how hard you are on the battery.

The theory is that if you completely discharge the battery by letting it run out completely, then recharge the battery back to full, it gives the meter a more accurate reading of the power remaining in the battery (and helps remove against memory effects - this an issue with li-ion?)
 
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