diff --git a/Cargo.toml b/Cargo.toml
index cb9fdeb..6131b0c 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -16,7 +16,7 @@ members = [
 ]
 
 [workspace.package]
-version = "0.4.0"
+version = "0.4.1"
 edition = "2021"
 repository = "https://git.bfpower.io/BFPOWER/physical"
 readme = "README.md"
diff --git a/src/quantity/voltage.rs b/src/quantity/voltage.rs
index 682a8ba..f7e12ed 100644
--- a/src/quantity/voltage.rs
+++ b/src/quantity/voltage.rs
@@ -8,7 +8,7 @@ quantity_type! {Volts, "V"}
 
 impl<V: Value> Volts<V> {
     #[inline]
-    pub fn to_millivolts(self) -> MilliVolts<V> {
+    pub fn to_milli_volts(self) -> MilliVolts<V> {
         let multiplier = V::from_u16(VOLT_MV_RATIO).unwrap();
         MilliVolts(self.0 * multiplier)
     }
@@ -37,7 +37,7 @@ mod tests {
         let volts: Volts<u32> = 3.volts();
         let millivolts: MilliVolts<u32> = 3_000.milli_volts();
 
-        assert_eq!(volts.to_millivolts().0, millivolts.0);
+        assert_eq!(volts.to_milli_volts().0, millivolts.0);
         assert_eq!(millivolts.to_volts().0, volts.0);
     }
 
@@ -46,7 +46,7 @@ mod tests {
         let volts: Volts<f64> = 3.0.volts();
         let millivolts: MilliVolts<f64> = 3_000.0.milli_volts();
 
-        assert_approx_eq!(f64, volts.to_millivolts().0, millivolts.0);
+        assert_approx_eq!(f64, volts.to_milli_volts().0, millivolts.0);
         assert_approx_eq!(f64, millivolts.to_volts().0, volts.0);
     }
 }