Your laptop battery is one of the most critical components and often the first to give you problems. If you own a Mac, you can get detailed information about your battery with a few simple clicks of the mouse.
A window will appear, showing information about your Mac.
Click on the Power heading, located under Hardware in the list of Contents on the left hand side of the System Profiler window. Battery and other Power Settings information will be displayed in the right-hand pane.
The Model Information section shows the battery’s serial number, manufacturer and other data about its manufacture.
The Charge Information and Health Information sections are the ones which you want to keep an eye on.
A charge cycle is couunted when the battery is run flat and then recharged to full capacity. If you run the battery partly down and recharge it, that will count as part of one cycle.
The battery’s capacity to store a charge is measure in Milliamps Per Hour (mAh).
My battery is only in ‘fair’ health. It has been through 547 charge cycles, which is a reasonable number and its full capacity is only 3088 mAh. As an indication, the full capacity of a new Apple MacBook Pro battery for my particular model is 5500mAh. So for my battery, its best days are most definitely behind it!
Apple expects your battery to retain approximately 80% of its charge after about 300 full cycles, so you can use this measure to gauge how your battery is performing.
Go check your battery today. It just might forewarn you of potential problems ahead.