diff --git a/src/battery/battery.c b/src/battery/battery.c
index 8e65e1a..babedf1 100644
--- a/src/battery/battery.c
+++ b/src/battery/battery.c
@@ -258,8 +258,6 @@ void init_battery_panel(void *p)
 
 
 int update_battery() {
-	int64_t energy_now = 0,
-			energy_full = 0;
 	int seconds = 0;
 	int8_t new_percentage = 0;
 	int errors = 0;
@@ -337,7 +335,7 @@ int update_battery() {
 	else
 		new_percentage = sysctl_out;
 #else
-	update_linux_batteries(&battery_state.state, &energy_now, &energy_full, &seconds);
+	update_linux_batteries(&battery_state.state, &new_percentage, &seconds);
 #endif
 
 	battery_state.time.hours = seconds / 3600;
@@ -346,9 +344,6 @@ int update_battery() {
 	seconds -= 60 * battery_state.time.minutes;
 	battery_state.time.seconds = seconds;
 
-	if (energy_full > 0)
-		new_percentage = 0.5 + ((energy_now <= energy_full ? energy_now : energy_full) * 100.0) / energy_full;
-
 	battery_state.percentage = new_percentage;
 
 	// clamp percentage to 100 in case battery is misreporting that its current charge is more than its max
diff --git a/src/battery/battery.h b/src/battery/battery.h
index c016637..f9441da 100644
--- a/src/battery/battery.h
+++ b/src/battery/battery.h
@@ -96,7 +96,7 @@ void battery_action(int button);
 #ifdef __linux
 gboolean init_linux_batteries();
 void free_linux_batteries();
-void update_linux_batteries(enum chargestate *state, gint64 *energy_now, gint64 *energy_full, int *seconds);
+void update_linux_batteries(enum chargestate *state, int8_t *percentage, int *seconds);
 char* linux_batteries_get_tooltip();
 #endif
 
diff --git a/src/battery/linux.c b/src/battery/linux.c
index 8dcabb2..6234c82 100644
--- a/src/battery/linux.c
+++ b/src/battery/linux.c
@@ -48,6 +48,10 @@ struct psy_battery {
 
 static GList *batteries = NULL;
 
+static guint8 energy_to_percent(gint energy_now, gint energy_full) {
+	return 0.5 + ((energy_now <= energy_full ? energy_now : energy_full) * 100.0) / energy_full;
+}
+
 static gboolean power_supply_is_battery(const gchar *entryname) {
 	gchar *path_type = g_build_filename("/sys/class/power_supply", entryname, "type", NULL);
 	GError *error = NULL;
@@ -237,7 +241,7 @@ static gboolean update_linux_battery(struct psy_battery *bat) {
 	return TRUE;
 }
 
-void update_linux_batteries(enum chargestate *state, gint64 *energy_now, gint64 *energy_full, int *seconds) {
+void update_linux_batteries(enum chargestate *state, int8_t *percentage, int *seconds) {
 	GList *l;
 
 	gint64 total_energy_now = 0;
@@ -261,10 +265,6 @@ void update_linux_batteries(enum chargestate *state, gint64 *energy_now, gint64
 		full |= (bat->status == BATTERY_FULL);
 	}
 
-	/* global energy stats */
-	*energy_now = total_energy_now;
-	*energy_full = total_energy_full;
-
 	/* build global state */
 	*state = BATTERY_UNKNOWN;
 	if (charging && !discharging)
@@ -282,6 +282,9 @@ void update_linux_batteries(enum chargestate *state, gint64 *energy_now, gint64
 		else if(*state == BATTERY_DISCHARGING)
 			*seconds = 3600 * total_energy_now / total_power_now;
 	}
+
+	/* calculate percentage */
+	*percentage = energy_to_percent(total_energy_now, total_energy_full);
 }
 
 static gchar* energy_human_readable(struct psy_battery *bat) {
@@ -341,7 +344,7 @@ char* linux_batteries_get_tooltip() {
 		gchar *energy = energy_human_readable(bat);
 		gchar *state = (bat->status == BATTERY_UNKNOWN) ? "Level" : chargestate2str(bat->status);
 
-		guint percentage = 0.5 + ((bat->energy_now <= bat->energy_full ? bat->energy_now : bat->energy_full) * 100.0) / bat->energy_full;
+		guint8 percentage = energy_to_percent(bat->energy_now, bat->energy_full);
 
 		g_string_append_printf(tooltip, "\t%s: %s (%u %%)\n\tPower: %s",
 			state, energy, percentage, power);