AceNeerav wrote:
Hi,
My macbook is 6 months old and I have had 128 charge cycles so far. The battery life has reduced to 94% (3845 mAh) from the original 4100 mAh.
That sounds just about right. In fact, your battery might even be above average. The typical result that Apple reports is 300 cycles to an average 80% of original capacity. It's not really a linear progression, but your numbers sound fine. Loss of capacity from using and recharging a rechargeable battery is inevitable. There might be some extreme things that can be done for exponentially higher battery life, but I don't think most people would be able to do these things adequately. Let's just say you would have to ALWAYS keep the battery's state of charge between 40 to 75%. This is what hybrid cars do with their batteries, and this maintains their capacity for a long time.
Rechargeable batteries lose capacity all the time. There is better technology (like Apple's new supposedly 1000 cycle batteries) but all will suffer the same fate given enough usage. I've replaced Li-ion cell phone batteries that suddenly lost their charge, and just recently I replaced a car battery. That's what rechargeable batteries do. They hopefully give you a long life, but a little piece of their capacity is reduced for every discharge-charge cycle.
I recalibrated my battery yesterday using the procedure provided on this website here...
http://support.apple.com/kb/HT1490
However, there is no change. This loss of battery life is indicated in 3 different places... the System Profilers, Battery health monitor and iStat Nano widget.
Battery calibration only updates the information on the state of the battery and gives the charging system a better idea of what condition it's in. You might get it reporting the occasional percentage point higher if the previous information was off after not being calibrated regularly. Battery calibration won't restore battery capacity that was truly lost. If it's lost, it's not coming back.
What can I d to save my battery from eventual death?
Don't use battery power if you can find a place to plug in. Calibrate maybe once a month.
If you need to use your machine on battery power, the loss of capacity is inevitable.