please I need a new battery model A1664 for iPad 9.7

You need to search online for your nearest, “local” Apple store location and call contact phone numbers and call to make an appointment to have your Apple iPad diagnosed and options presented you.

Failing that,

You need to contact Apple support via the contact support link located at the upper right hand corner of every Webpage of these Apple support communities.

Use the Hardware Repair & Battery usage & Charging support categories.

OR

by installing and using the Apple Support app found in the iOS App Store.

Tap the iOS App Store link below.

https://apps.apple.com/us/app/apple-support/id1130498044

OR

Call contact Apple via the support numbers found in the link bekow.

Contact - How to Contact Us - Apple

Tap the link below.

https://www.apple.com/contact/

Best of Luck to You!

Also, in most countries, Apple does NOT do repairs or battery replacements on iPads.

Apple Stores ONLY do in/out warranty device replacement for any repairs OR battery replacement.

If, IF your older iPad has no external damage, an out of warranty device replacement, in lieu of an actual battery replacement, will cost $99 U.S.D..

If that iPad has any noticeable dents, bends or other signs of possible hardware damages, out of warranty costs could increase significantly.

Best of Luck to You!