Bangle.js 2 - Battery always 100%

@fanoush You're right, only hi should be needed. I'm now experimenting with trying to get getBattery to be more accurate since volts/% is not linear. My daughter noted that her watch was claiming 40% remaining battery shortly before it shut down. Based on a discharge graph shown here https://learn.adafruit.com/li-ion-and-lipoly-batteries/voltages, I've come up with the following:

E.getBattery = function () {
    const hi = 0.48;
    var v = analogRead(D3) / hi * 4.2;
    if (v >= 4.2) {
        return 100;
    } else if (v >= 4.1) {
        return Math.round(97 + 30 * (v - 4.1));
    } else if (v >= 4.0) {
        return Math.round(87 + 100 * (v - 4.0));
    } else if (v >= 3.9) {
        return Math.round(75 + 120 * (v - 3.9));
    } else if (v >= 3.8) {
        return Math.round(59 + 160 * (v - 3.8));
    } else if (v >= 3.7) {
        return Math.round(26 + 330 * (v - 3.7));
    } else if (v >= 3.6) {
        return Math.round(12 + 140 * (v - 3.6));
    } else if (v >= 3.5) {
        return Math.round(6 + 60 * (v - 3.5));
    } else if (v >= 3.4) {
        return Math.round(3 + 30 * (v - 3.4));
    } else {
        return 0;
    }
};