diff --git a/src/battery_utils.cpp b/src/battery_utils.cpp
index b33f12e..8b1d79a 100644
--- a/src/battery_utils.cpp
+++ b/src/battery_utils.cpp
@@ -1,3 +1,4 @@
+#include <Arduino.h>
 #include "battery_utils.h"
 #include "configuration.h"
 #include "boards_pinout.h"