In the Taobao seller backend, you can follow the steps below to set up 24-hour delivery in batches:

1. Log in to your Taobao seller backend.

2. Click "Transaction Management" in the left navigation bar.

3. Click "Order Management".

4. On the order management page, select the orders you need to set up in batches, and then click the "Batch Operation" button.

5. Select the "Batch Modify Delivery Time" option in the drop-down menu.

6. In the pop-up window, set "Delivery Time" to "Within 24 hours".

7. Click the "OK" button to complete the batch setting.

In this way, you can set the delivery time of the selected orders to within 24 hours.