Our 2007 Macbook Pro said: “Replace Battery Immediately”.
I bought a replacement on Lazada online, it got delivered within a week, opened the Macbook and once I had removed the screws the back popped open. The old battery swollen.
Replaced it within 10 minutes, back to normal, for another 10 years. Despite all the Apple Bashing, I never had a windows computer for more than 5 years.