If I use a magsafe case on my iPhone 11, can I use the magsafe battery pack?

In order to use the battery pack, you will need to have an iPhone 12 or higher, according to apples product specifications in the online store

Thanks for posting in the Apple Support Communities AdamSaeed123,

If you use an Apple case with MagSafe, you can leave the case on your iPhone and attach the MagSafe Battery to charge.

If you use a case from another manufacturer, you may want to check with the manufacturer on what capabilities are supported while using their case.

You can find additional information about the MagSafe Battery here: How to use your MagSafe Battery Pack

We hope this helps!