Macbook Air Battery Replacement

Not directly from Apple, but if you were to contact Apple they can probably refer you to an authorized Apple repair facility that may be able to help. Start here: Get Support.

To find one on your own, start here: https://locate.apple.com/ and scroll down to Explore Service Locations.

While Apple recently changed their policy and now offers Battery replacement for up to 10 years (as long as parts are still available), this change was introduced after this laptop became "Obsolete" so I doubt Apple or an AASP will be able to provide an official Apple battery repair. However, some AASPs may provide an option to replace the battery with a third party battery.

If Apple does not provide a battery repair for this laptop, then your best option for a third party battery is from OWC. I would not purchase a third party battery from anyone else since the quality of third party Lithium-ion batteries is extremely poor. I will always prefer an official OEM battery repair over using a third party battery, but sometimes it just is not possible. It is a relatively easy replacement for this model and OWC does provide video installation guides for reference, plus some repair shops will perform the installation for you.