Originally Posted by gsa103

Thanks for the link, I had been looking for data like that. I was really curious to see how battery charging impacts life.

Using 100-25% charge (75% eff. cap) = 2100 cycles to 85% remaining.
Using 85-25% charge (60% eff. cap) = 4500 cycles to 85% -- 1.7x lifespan of 100-25 cycle
Using 75-25 charge (50% eff. cap) = 7000 cycles to 85% -- 2.2x lifespan of 100-25 cycle
Using 75-45 charge (30% eff. cap) = ~10k cycles to 85% -- 1.9x lifespan of 100-25

The effective lifespan actually goes down for lowest duty cycles. For example, compared to the 85-25 case, it takes 2 cycles of 75-45 for each 85-25 cycle, which means that its effective lifespan is ~5k cycles and very close to the 85-25 depth cycle.

TL;DR -- 85%-25% is basically the optimum for battery lifespan, anything else offers minor improvements at best.