diff --git a/src/main/java/com/glodblock/github/appflux/common/me/cell/FluxCellInventory.java b/src/main/java/com/glodblock/github/appflux/common/me/cell/FluxCellInventory.java
index ddc30834..2a215245 100644
--- a/src/main/java/com/glodblock/github/appflux/common/me/cell/FluxCellInventory.java
+++ b/src/main/java/com/glodblock/github/appflux/common/me/cell/FluxCellInventory.java
@@ -14,6 +14,7 @@
 import com.glodblock.github.appflux.common.me.key.FluxKey;
 import com.glodblock.github.appflux.common.me.key.type.EnergyType;
 import com.glodblock.github.appflux.common.me.key.type.FluxKeyType;
+import com.glodblock.github.appflux.config.AFConfig;
 import net.minecraft.network.chat.Component;
 import net.minecraft.world.item.ItemStack;
 import org.jetbrains.annotations.Nullable;
@@ -88,15 +89,16 @@ public long insert(AEKey what, long amount, Actionable mode, IActionSource sourc
         if (!(what instanceof FluxKey)) {
             return 0;
         }
-
-        var inserted = Math.min(getMaxEnergy() - this.storedEnergy, amount);
+        var convertedAmount = (long)(amount * AFConfig.getConversionRate());
+        var inserted = Math.min(getMaxEnergy() - this.storedEnergy, convertedAmount);
 
         if (mode == Actionable.MODULATE) {
             this.storedEnergy += inserted;
             saveChanges();
         }
 
-        return this.hasVoidUpgrade ? amount : inserted;
+        // Need to return the amount before conversion loss so it will be deducted from the source correctly.
+        return this.hasVoidUpgrade ? amount : (long)(inserted / AFConfig.getConversionRate());
     }
 
     @Override
diff --git a/src/main/java/com/glodblock/github/appflux/config/AFConfig.java b/src/main/java/com/glodblock/github/appflux/config/AFConfig.java
index d02dc3c7..1490d838 100644
--- a/src/main/java/com/glodblock/github/appflux/config/AFConfig.java
+++ b/src/main/java/com/glodblock/github/appflux/config/AFConfig.java
@@ -14,6 +14,9 @@ public class AFConfig {
     private static final ModConfigSpec.IntValue FLUX_PER_BYTE = BUILDER
             .comment("FE can be stored per byte.")
             .defineInRange("flux_cell.amount", 1024 * 1024, 1, Integer.MAX_VALUE);
+    private static final ModConfigSpec.DoubleValue CONVERSION_LOSS_RATE = BUILDER
+            .comment("Percentage of FE lost when stored into Flux Cells.")
+            .defineInRange("flux_cell.conversion_loss_percentage", 0.025, 0, 0.999999);
     private static final ModConfigSpec.LongValue FLUX_ACCESSOR_IO = BUILDER
             .comment("The I/O limit of Flux Accessor. 0 means no limitation.")
             .defineInRange("flux_accessor.io_limit", 0L, 0L, Integer.MAX_VALUE);
@@ -34,6 +37,10 @@ public static int getFluxPerByte() {
         return fluxPerByte;
     }
 
+    public static double getConversionRate() {
+        return conversionRate;
+    }
+
     public static long getFluxAccessorIO() {
         return fluxAccessorIO <= 0 ? Long.MAX_VALUE : fluxAccessorIO;
     }
@@ -51,6 +58,7 @@ public static boolean miSupport() {
     }
 
     private static int fluxPerByte;
+    private static double conversionRate;
     private static long fluxAccessorIO;
     private static boolean selfCharge;
     private static boolean allowImportBus;
@@ -59,6 +67,7 @@ public static boolean miSupport() {
     @SubscribeEvent
     static void onLoad(final ModConfigEvent event) {
         fluxPerByte = FLUX_PER_BYTE.get();
+        conversionRate = 1.0 - CONVERSION_LOSS_RATE.get();
         fluxAccessorIO = FLUX_ACCESSOR_IO.get();
         selfCharge = NETWORK_CHARGE.get();
         allowImportBus = ENABLE_IMPORT.get();
diff --git a/src/main/resources/assets/appflux/ae2guide/appflux/flux_accessor.md b/src/main/resources/assets/appflux/ae2guide/appflux/flux_accessor.md
index 29f71b66..b447a445 100644
--- a/src/main/resources/assets/appflux/ae2guide/appflux/flux_accessor.md
+++ b/src/main/resources/assets/appflux/ae2guide/appflux/flux_accessor.md
@@ -25,6 +25,8 @@ changed in Appflux config.
 They have fast and normal mode. In fast mode, it outputs energy in every tick, which may cause lag if it is heavily used.
 In normal mode, it outputs energy depends on target's stored energy, which won't cause lag issues.
 
+When the Flux Accessor is storing energy to FE Storage Cells, a percentage of the incoming energy is lost. The default is 2.5%,
+matching the default loss when transfering energy via an Energy P2P Tunnel. This percentage is configurable.
+
 * Notice: The "energy" mentioned here is FE stored in your [FE Storage Cells](./flux_cells.md), not the energy in
 [Energy Cells](ae2:items-blocks-machines/energy_cells.md).
-