I used a Newer Technology NuPower battery for my spouse’s 2014 Air and it has been great for a few years. Bonus: it was super easy to install. It looks like that might be the same battery for a 2017, but I’m not sure. I bought mine from OWC.

I have used no-name batteries from eBay many years ago in a plastic case MacBook, and I was not thrilled with them. They swelled and stopped taking a charge sooner that I would have liked. I recommend spending a little extra on something from a recognized name like Newer Tech if it’s available in your area.