Looking for Genuine Dell Latitude 5480 Battery with Original Backup Performance

Hi everyone,
I’m using a Dell Latitude 5480, and the original battery used to give a solid 5–6 hours of backup, which was perfect for my workflow. Unfortunately, it’s no longer holding a charge, and I’m looking to replace it.

I want to purchase a genuine Dell battery that offers the same backup performance (5–6 hours). Can anyone from the community or Dell support guide me on where to find an original, high-quality replacement—preferably from a trusted source?

Would also appreciate any tips on verifying authenticity before buying.
Thanks in advance!