Peel the black pull tab from battery and pull slowly but firmly to separate the battery from the frame.

A few drops of high concentration (90% or higher) isopropyl alcohol along each side may help soften the adhesive.

If the pull tab breaks, use a spudger to gently pry around the edges of the battery until it comes loose.

Don't deform or puncture the battery—it can catch fire and/or explode if damaged.

Never reinstall a damaged or deformed battery. Replace the battery.