Use the flat end of a spudger to gently pry up the RTC battery, separating the adhesive securing it to the frame.

Remove the RTC battery.

If your replacement battery comes with adhesive pre‑installed, remove the old adhesive from the frame before installing the new battery.

If it doesn't, you can reuse the adhesive if it's still sticky. If not, use thin, double‑sided tape to secure your new battery.