This battery phenomenon actually boggles my mind, if somebody knows what's going on and is willing to help clarify.
Lithium batteries are lithium batteries. They all degrade over time and with cycle count, nothing manufacturers can do about it.
But why are lithium batteries from the GameBoy Advance still capable of holding a charge today, and why you can find old power sucking laptops with original batteries that at least hold charge for an hour, but modern lithium batteries simply die after three years?