# Refill
You can charge your Hero NFTs at the charging station to restore their energy.
Click the **\[+]** button of the charging station to select the hero that needs to be charged.
Click **\[CONFIRM]** to charge. It takes a certain amount of time to charge, and the hero under charing will display the charging time required.
**Batch Charging:**
Heroes can be collected into batches for charging.
**Batch Removal:**
Remove all charging heroes.
**Charging Slot Unlocked:**
Each player initially has 3 charging slots.
Each time a dungeon challenge is completed, an additional charging slot can be obtained, with 19 slots at maximum.VIP users can obtain 3 additional charging slots, with 22 in total.
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