> He multiplies by 1.59 annually and gets a 25X increase in total battery in seven years. That actually takes eight years, but whatever. (1.59)^7 = 25.69 But

> He multiplies by 1.59 annually and gets a 25X increase in total battery in seven years. That actually takes eight years, but whatever. (1.59)^7 = 25.69 But yeah, not eight doublings. I guess we'll have to wait another four years then :).