To be clear, this isn't actually a real thing. Think of it this way: You buy a 400hp car. You run it hard for 10 years, put 150,000 miles on it, then put it on a dyno. Are you really pissed that it only turns 300hp now? Of course not. Your car isn't expected to as good as it once was because parts wear down and things become less efficient in time. Lithium-Ion batteries are AWFUL at sustaining a maximum charge point, especially when baked into the horrific ways we all use our phones (hot weather, random charging times, no ventilation, etc). Yet you put a Li-Ion battery in a car and it can easily run for a decade, often much longer than that. Why the difference? Cooling. And battery monitoring. All those cells give the opportunity for displacement of use, heat, and power, which can be controlled by a computer. And cooling keeps the entire battery in check and optimizes itself for longevity. A phone? Nah, you just churn and burn them because the money isn't there to attempt that sort of thing because people simply don't give a ****.