diff --git a/main/battery.h b/main/battery.h
index 07ca95e..ffb340f 100644
--- a/main/battery.h
+++ b/main/battery.h
@@ -17,25 +17,98 @@ DECLARE_TYPESAFE_ENUM(BatteryCellType, : uint8_t, BatteryCellTypeValues)
 
 namespace {
 
+float mapFloat(float x, float in_min, float in_max, float out_min, float out_max) {
+    return (x - in_min) * (out_max - out_min) / (in_max - in_min) + out_min;
+}
+#define CURVE(higherVoltage,lowerVoltage,fromAh,toAh) if(cellVoltage >= lowerVoltage && cellVoltage <= higherVoltage) return 100 * mapFloat(cellVoltage, higherVoltage, lowerVoltage, fromAh, toAh) / expected_ah;
+
 float getBatteryPercentage(float batVoltage, BatteryCellType cellType)
 {
-    float percentage = 12.34;
+    const float cellVoltage = batVoltage / settings.battery.cellsSeries;
+
     switch (cellType) {
-        case BatteryCellType::_22P:
+        case BatteryCellType::_22P: {
+            const float expected_ah = 2.2;
+            CURVE(4.15, 4.04, 0, 0.25)
+            CURVE(4.04, 3.95, 0.25, 0.5)
+            CURVE(3.95, 3.86, 0.5, 0.75)
+            CURVE(3.86, 3.74, 0.75, 1.0)
+            CURVE(3.74, 3.64, 1.0, 1.25)
+            CURVE(3.64, 3.59, 1.25, 1.5)
+            CURVE(3.59, 3.54, 1.5, 1.75)
+            CURVE(3.54, 3.43, 1.75, 2.0)
+            CURVE(3.43, 3.35, 2.0, 2.1)
+            CURVE(3.35, 2.50, 2.1, 2.2)
             break;
-        case BatteryCellType::MH1:
+        }
+        case BatteryCellType::MH1: {
+            const float expected_ah = 3.2;
+            CURVE(4.15, 4.09, 0, 0.25)
+            CURVE(4.09, 4.04, 0.25, 0.5)
+            CURVE(4.04, 3.95, 0.5, 0.75)
+            CURVE(3.95, 3.88, 0.75, 1.0)
+            CURVE(3.88, 3.79, 1.0, 1.25)
+            CURVE(3.79, 3.70, 1.25, 1.5)
+            CURVE(3.70, 3.65, 1.5, 1.75)
+            CURVE(3.65, 3.60, 1.75, 2.0)
+            CURVE(3.60, 3.56, 2.0, 2.25)
+            CURVE(3.56, 3.50, 2.25, 2.5)
+            CURVE(3.50, 3.40, 2.5, 2.75)
+            CURVE(3.40, 3.30, 2.75, 3.0)
+            CURVE(3.30, 2.5, 3.0, 3.2)
             break;
-        case BatteryCellType::HG2:
+        }
+        case BatteryCellType::HG2: {
+            const float expected_ah = 3.0;
+            CURVE(4.15, 4.08, 0, 0.25)
+            CURVE(4.08, 4.01, 0.25, 0.5)
+            CURVE(4.01, 3.92, 0.5, 0.75)
+            CURVE(3.92, 3.84, 0.75, 1.0)
+            CURVE(3.84, 3.75, 1.0, 1.25)
+            CURVE(3.75, 3.67, 1.25, 1.5)
+            CURVE(3.67, 3.62, 1.5, 1.75)
+            CURVE(3.62, 3.55, 1.75, 2.0)
+            CURVE(3.55, 3.44, 2.0, 2.25)
+            CURVE(3.44, 3.30, 2.25, 2.5)
+            CURVE(3.30, 3.05, 2.5, 2.75)
+            CURVE(3.05, 2.50, 2.75, 3.0)
             break;
-        case BatteryCellType::VTC5:
+        }
+        case BatteryCellType::VTC5: {
+            const float expected_ah = 2.6;
+            CURVE(4.15, 4.08, 0, 0.25)
+            CURVE(4.08, 3.98, 0.25, 0.5)
+            CURVE(3.98, 3.89, 0.5, 0.75)
+            CURVE(3.89, 3.79, 0.75, 1.0)
+            CURVE(3.79, 3.71, 1.0, 1.25)
+            CURVE(3.71, 3.64, 1.25, 1.5)
+            CURVE(3.64, 3.53, 1.5, 1.75)
+            CURVE(3.53, 3.44, 1.75, 2.0)
+            CURVE(3.44, 3.20, 2.0, 2.25)
+            CURVE(3.20, 2.80, 2.25, 2.5)
+            CURVE(2.80, 2.50, 2.5, 2.60)
             break;
+        }
     }
-    return percentage;
+    return 0.f;
 }
 
 float getRemainingWattHours()
 {
-    return 42.69;
+    float target_mah = 2000; //default
+    if(BatteryCellType(settings.battery.cellType) == BatteryCellType::_22P) target_mah = 2200;
+    if(BatteryCellType(settings.battery.cellType) == BatteryCellType::HG2) target_mah = 3000;
+    if(BatteryCellType(settings.battery.cellType) == BatteryCellType::MH1) target_mah = 3200;
+    if(BatteryCellType(settings.battery.cellType) == BatteryCellType::VTC5) target_mah = 2600;
+
+    float avgVoltage = 0;
+    for (auto &controller : controllers)
+    {
+        avgVoltage += controller.getCalibratedVoltage(settings.battery.applyCalibration);
+    }
+    avgVoltage = avgVoltage / controllers.size();
+
+    return (target_mah / 1000.f) * 3.7 * settings.battery.cellsParallel * settings.battery.cellsSeries * (getBatteryPercentage(avgVoltage, BatteryCellType(settings.battery.cellType)) / 100);
 }
 
 std::string getBatteryPercentageString()