diff --git a/libraries/AP_BattMonitor/AP_BattMonitor.cpp b/libraries/AP_BattMonitor/AP_BattMonitor.cpp
index 133358bda1..3abad91421 100644
--- a/libraries/AP_BattMonitor/AP_BattMonitor.cpp
+++ b/libraries/AP_BattMonitor/AP_BattMonitor.cpp
@@ -376,14 +376,13 @@ bool AP_BattMonitor::consumed_wh(float &wh, const uint8_t instance) const {
     }
 }
 
-/// capacity_remaining_pct - returns the % battery capacity remaining (0 ~ 100)
-uint8_t AP_BattMonitor::capacity_remaining_pct(uint8_t instance) const
+/// capacity_remaining_pct - returns true if the percentage is valid and writes to percentage argument
+bool AP_BattMonitor::capacity_remaining_pct(uint8_t &percentage, uint8_t instance) const
 {
     if (instance < _num_instances && drivers[instance] != nullptr) {
-        return drivers[instance]->capacity_remaining_pct();
-    } else {
-        return 0;
+        return drivers[instance]->capacity_remaining_pct(percentage);
     }
+    return false;
 }
 
 /// pack_capacity_mah - returns the capacity of the battery pack in mAh when the pack is full
diff --git a/libraries/AP_BattMonitor/AP_BattMonitor.h b/libraries/AP_BattMonitor/AP_BattMonitor.h
index 33289a73a5..4dcac08abf 100644
--- a/libraries/AP_BattMonitor/AP_BattMonitor.h
+++ b/libraries/AP_BattMonitor/AP_BattMonitor.h
@@ -161,9 +161,9 @@ public:
     /// consumed_wh - returns total energy drawn since start-up in watt.hours
     bool consumed_wh(float&wh, const uint8_t instance = AP_BATT_PRIMARY_INSTANCE) const WARN_IF_UNUSED;
 
-    /// capacity_remaining_pct - returns the % battery capacity remaining (0 ~ 100)
-    virtual uint8_t capacity_remaining_pct(uint8_t instance) const;
-    uint8_t capacity_remaining_pct() const { return capacity_remaining_pct(AP_BATT_PRIMARY_INSTANCE); }
+    /// capacity_remaining_pct - returns true if the percentage is valid and writes to percentage argument
+    virtual bool capacity_remaining_pct(uint8_t &percentage, uint8_t instance) const WARN_IF_UNUSED;
+    bool capacity_remaining_pct(uint8_t &percentage) const WARN_IF_UNUSED { return capacity_remaining_pct(percentage, AP_BATT_PRIMARY_INSTANCE); }
 
     /// pack_capacity_mah - returns the capacity of the battery pack in mAh when the pack is full
     int32_t pack_capacity_mah(uint8_t instance) const;