What is this strange balance transfer that occurs during utility.batch?

Question

I'm putting a single transaction into a batch utility call with zero value. The batch extrinsic is shown below. Each time I submit the batch transaction, a huge value is submitted to an unknown account. The value is approximately 500 times the gas fee of the single transaction in the batch. The receiving account is not a contract. It is always the same account that receives the balance.

What is this balance transfer for?

I'm using substrate in dev mode on branch polkadot-v0.9.40.

Batch Extrinsic:

{
  "isSigned": true,
  "method": {
    "args": {
      "calls": [
        {
          "args": {
            "dest": {
              "Id": "5Fmo4KdCK7jTLbaSbZ5RYXhYMZxzPCxEv7SVHwzTJ3WUbGJJ"
            },
            "value": "0",
            "gas_limit": {
              "refTime": "9,946,641,144",
              "proofSize": "709,519"
            },
            "storage_deposit_limit": "1,448,339,956,379,238",
            "data": "0x5b965eaba456d313ea79628d7a768d77e3e5089289c4ada9170a647895125b73c3c1eee80105797b3529e14b9ff72548ef16865d4d9e0f79f1e393decd2f435ff5f2cc0c133b73f06b9945447b664b3f12cf45d227a315623db8611b110b2955b2531c10340f9161523bb730b4a180f9ab0144f89ce5d0c09d0934a386fbd3b804a0a9675a0b71a30f2531b3ac73f88bd8d0a15f1e3ce7840d456947a9c3235ff5f40e720101"
          },
          "method": "call",
          "section": "contracts"
        }
      ]
    },
    "method": "batch",
    "section": "utility"
  },
  "era": {
    "MortalEra": {
      "period": "128",
      "phase": "117"
    }
  },
  "nonce": "3",
  "signature": "0x01010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101010101",
  "signer": {
    "Id": "5DExyKNTzoweUafckatwBs4TDCyPH4C4zjXJhJpPzP8J7xqr"
  },
  "tip": "0"
}

The hex encoded extrinsic:

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

Answer 1

Edited after feedback from @German Nikolishin below.

It seems this transfer is the cost associated with storing data in the contract. The value inside the transfer is sent to what I presume is the contract's deposit_account, which is why it isn't a contract itself.

The value sent to the deposit_account is the storageDeposit

faucetWithStore response.storageDeposit { Charge: '480.0000 Unit' }

The deposit stays in the deposit account until the contract is terminated, at which point the deposit account uses the funds to remove any storage associated with the contract and then sends the remaining funds back to the recipient.

            ink::env::terminate_contract::<ink::env::DefaultEnvironment>(recipient);

I've created a demo repo to demonstrate the fees shown above.