@josecastillo Forgot to post this yesterday! Battery test, day 390: 2.51 volts. I think we're finally near the end with the old firmware; I expect it'll die within a week or two. There's an app note that once the LCD voltage is more than 700 mV above the system voltage, current consumption increases, and I think I can see that on the red line: it's dropping faster now that we've crossed the threshold. New, more efficient firmware though: still going strong! 3.07 volts at day 285.