diff --git a/openbsd/Battery.c b/openbsd/Battery.c
index f9d0969a..3a0bae14 100644
--- a/openbsd/Battery.c
+++ b/openbsd/Battery.c
@@ -7,10 +7,65 @@ in the source distribution for its full text.
 */
 
 #include "BatteryMeter.h"
+#include <sys/sysctl.h>
+#include <sys/sensors.h>
+#include <errno.h>
 
-void Battery_getData(double* level, ACPresence* isOnAC) {
-   // TODO
-   *level = -1;
-   *isOnAC = AC_ERROR;
+static bool findDevice(const char* name, int* mib, struct sensordev* snsrdev, size_t* sdlen) {
+   for (int devn = 0;; devn++) {
+      mib[2] = devn;
+      if (sysctl(mib, 3, snsrdev, sdlen, NULL, 0) == -1) {
+         if (errno == ENXIO)
+            continue;
+         if (errno == ENOENT)
+            return false;
+      }
+      if (strcmp(name, snsrdev->xname) == 0) {
+         return true;
+      }
+   }
 }
 
+void Battery_getData(double* level, ACPresence* isOnAC) {
+   static int mib[] = {CTL_HW, HW_SENSORS, 0, 0, 0};
+   struct sensor s;
+   size_t slen = sizeof(struct sensor);
+   struct sensordev snsrdev;
+   size_t sdlen = sizeof(struct sensordev);
+
+   bool found = findDevice("acpibat0", mib, &snsrdev, &sdlen);
+   
+   *level = -1;
+   if (found) {
+      /* last full capacity */
+      mib[3] = 7;
+      mib[4] = 0;
+      double last_full_capacity = 0;
+      if (sysctl(mib, 5, &s, &slen, NULL, 0) != -1) {
+         last_full_capacity = s.value;
+      }
+      if (last_full_capacity > 0) {
+         /*  remaining capacity */
+         mib[3] = 7;
+         mib[4] = 3;
+         if (sysctl(mib, 5, &s, &slen, NULL, 0) != -1) {
+            double charge = s.value;
+            *level = 100*(charge / last_full_capacity);
+            if (charge >= last_full_capacity) {
+               *level = 100;
+            }
+         }
+      }
+   }
+   
+   found = findDevice("acpiac0", mib, &snsrdev, &sdlen);
+   
+   *isOnAC = AC_ERROR;
+   if (found) {
+      mib[3] = 9;
+      mib[4] = 0;
+      if (sysctl(mib, 5, &s, &slen, NULL, 0) != -1) {
+         *isOnAC = s.value;
+      }
+   }
+}