IFixIt: “Charging your phone’s battery to 100% is drastically shortening its useful life. But the fix is easy, and while auto companies have known about this and mitigated its consequences for some time, now most major smartphone brands—including Apple, Samsung, and Google—are finally jumping on board.  When we think about battery longevity, we think about the number of charging cycles that it can stand until it will no longer hold a useful charge. The li-ion batteries used in phones, laptops, and other rechargeable gadgets can be charge-cycled a limited number of times before they no longer hold a useful charge. That’s why we want manufacturers to design devices with replaceable batteries. But that’s not the whole story. How you charge the battery matters, and keeping the maximum charge below 100% can increase the most relevant stat: the total amount of energy the battery can deliver over its lifetime…”