The battery is strongly adhered to the Steam Deck. The adhesive loosens with constant, steady force, and it will require repeated heating and prying cycles.

Heating a charged battery is a fire hazard. Make sure you've completely discharged your battery before starting this step.

Don't reuse the battery after it's been removed, as doing so is a potential safety hazard. Replace it with a new battery.

Use a heat gun to heat the adhesive underneath the battery for 1-2 minutes.

Alternatively, a hair dryer may also be used.

Try your best to not overheat the battery or surrounding plastic components. Keep the heat gun or hair dryer ~2 inches above the battery and constantly moving at all times—don't keep it heating one place for too long.

Although high-concentration isopropyl alcohol (>90%) may be an effective method to loosen this adhesive, there's a high risk of excess leaking onto or into the display or other components through the cutouts on the battery tray.