Not all batteries are created equal, but one thing's for sure—they all lose capacity over time. Thankfully, the advanced lithium-ion batteries in your MacBook and iPhone are meant to last for several years before they begin to lose their overall charge capacity. Of course, that's under ideal conditions. Everything from an overload of apps running to excessive use and high temperatures can play a part in speeding up the deterioration of your battery—until one day when it stops working, acc...
