diff --git a/contracts/EthStorageContractL2.sol b/contracts/EthStorageContractL2.sol
index 7164417..6743311 100644
--- a/contracts/EthStorageContractL2.sol
+++ b/contracts/EthStorageContractL2.sol
@@ -20,6 +20,12 @@ interface IL1Block {
     function timestamp() external view returns (uint64);
 }
 
+/// @title ISoulGasToken
+/// @notice Interface for the SoulGasToken contract.
+interface ISoulGasToken {
+    function chargeFromOrigin(uint256 _amount) external returns (uint256);
+}
+
 /// @custom:proxied
 /// @title EthStorageContractL2
 /// @notice EthStorage contract that will be deployed on L2, and uses L1Block contract to mine.
@@ -36,6 +42,9 @@ contract EthStorageContractL2 is EthStorageContract2 {
     /// @notice A slot to store both `blockLastUpdate` (left 224) and `blobsUpdated` (right 32)
     uint256 internal updateState;
 
+    /// @notice The address of the soul gas token.
+    address public soulGasToken;
+
     /// @notice Constructs the EthStorageContractL2 contract.
     constructor(
         Config memory _config,
@@ -47,6 +56,28 @@ contract EthStorageContractL2 is EthStorageContract2 {
         UPDATE_LIMIT = _updateLimit;
     }
 
+    /// @notice Set the soul gas token address for the contract.
+    function setSoulGasToken(address _soulGasToken) external onlyOwner {
+        soulGasToken = _soulGasToken;
+    }
+
+    /// @inheritdoc StorageContract
+    function _checkAppend(uint256 _batchSize) internal virtual override {
+        uint256 kvEntryCountPrev = kvEntryCount - _batchSize; // kvEntryCount already increased
+        uint256 totalPayment = _upfrontPaymentInBatch(kvEntryCountPrev, _batchSize);
+        uint256 sgtCharged = 0;
+        if (soulGasToken != address(0)) {
+            sgtCharged = ISoulGasToken(soulGasToken).chargeFromOrigin(totalPayment);
+        }
+        require(msg.value >= totalPayment - sgtCharged, "EthStorageContractL2: not enough batch payment");
+
+        uint256 shardId = kvEntryCount >> SHARD_ENTRY_BITS; // shard id after the batch
+        if (shardId > (kvEntryCountPrev >> SHARD_ENTRY_BITS)) {
+            // Open a new shard and mark the shard is ready to mine.
+            infos[shardId].lastMineTime = _blockTs();
+        }
+    }
+
     /// @notice Get the current block number
     function _blockNumber() internal view virtual override returns (uint256) {
         return L1_BLOCK.number();
diff --git a/contracts/StorageContract.sol b/contracts/StorageContract.sol
index 529b00c..ade3604 100644
--- a/contracts/StorageContract.sol
+++ b/contracts/StorageContract.sol
@@ -175,7 +175,7 @@ abstract contract StorageContract is DecentralizedKV {
     }
 
     /// @notice Upfront payment for a batch insertion
-    function _upfrontPaymentInBatch(uint256 _kvEntryCount, uint256 _batchSize) private view returns (uint256) {
+    function _upfrontPaymentInBatch(uint256 _kvEntryCount, uint256 _batchSize) internal view returns (uint256) {
         uint256 shardId = _kvEntryCount >> SHARD_ENTRY_BITS;
         uint256 totalEntries = _kvEntryCount + _batchSize; // include the batch to be put
         uint256 totalPayment = 0;
diff --git a/contracts/test/EthStorageContractL2Test.t.sol b/contracts/test/EthStorageContractL2Test.t.sol
index 2427af8..b5b2e9b 100644
--- a/contracts/test/EthStorageContractL2Test.t.sol
+++ b/contracts/test/EthStorageContractL2Test.t.sol
@@ -5,6 +5,12 @@ import "forge-std/Test.sol";
 import "./TestEthStorageContractL2.sol";
 import "@openzeppelin/contracts/proxy/transparent/TransparentUpgradeableProxy.sol";
 
+contract SoulGasToken {
+    function chargeFromOrigin(uint256 _amount) external pure returns (uint256) {
+        return _amount;
+    }
+}
+
 contract EthStorageContractL2Test is Test {
     uint256 constant STORAGE_COST = 0;
     uint256 constant SHARD_SIZE_BITS = 19;
@@ -76,4 +82,51 @@ contract EthStorageContractL2Test is Test {
         vm.expectRevert("EthStorageContractL2: exceeds update rate limit");
         storageContract.putBlobs(keys, blobIdxs, lengths);
     }
+
+    function testSGTPayment() public {
+        TestEthStorageContractL2 imp = new TestEthStorageContractL2(
+            StorageContract.Config(MAX_KV_SIZE, SHARD_SIZE_BITS, 2, 0, 0, 0),
+            block.timestamp,
+            1500000000000000,
+            0,
+            UPDATE_LIMIT
+        );
+        bytes memory data = abi.encodeWithSelector(
+            storageContract.initialize.selector, 0, PREPAID_AMOUNT, 0, address(0x1), address(0x1)
+        );
+        TransparentUpgradeableProxy proxy = new TransparentUpgradeableProxy(address(imp), owner, data);
+
+        TestEthStorageContractL2 l2Contract = TestEthStorageContractL2(address(proxy));
+
+        uint256 size = 6;
+        bytes32[] memory hashes = new bytes32[](size);
+        bytes32[] memory keys = new bytes32[](size);
+        uint256[] memory blobIdxs = new uint256[](size);
+        uint256[] memory lengths = new uint256[](size);
+        for (uint256 i = 0; i < size; i++) {
+            keys[i] = bytes32(uint256(i));
+            hashes[i] = bytes32(uint256((i + 1) << 64));
+            blobIdxs[i] = i;
+            lengths[i] = 10 + i * 10;
+        }
+        vm.blobhashes(hashes);
+
+        vm.expectRevert("EthStorageContractL2: not enough batch payment");
+        l2Contract.putBlobs{value: 1500000000000000 * 5}(keys, blobIdxs, lengths);
+
+        l2Contract.putBlobs{value: 1500000000000000 * 6}(keys, blobIdxs, lengths);
+
+        SoulGasToken sgt = new SoulGasToken();
+        vm.prank(owner);
+        l2Contract.setSoulGasToken(address(sgt));
+
+        for (uint256 i = 0; i < size; i++) {
+            keys[i] = bytes32(uint256(i + 6));
+            hashes[i] = bytes32(uint256((i + 1) << 64));
+            blobIdxs[i] = i;
+            lengths[i] = 10 + i * 10;
+        }
+        vm.blobhashes(hashes);
+        l2Contract.putBlobs(keys, blobIdxs, lengths);
+    }
 }