Never reuse a deformed or damaged battery—it's a fire hazard. Replace it with a new battery.

Peel the battery away from the extra tape on its left edge and remove it.

During reassembly:

Temporarily reconnect the battery to the motherboard before you press it into place to ensure correct alignment. Disconnect the battery after it's seated.

Secure the new battery with pre-cut adhesive or double-sided adhesive tape. In order to position it correctly, apply the new adhesive into the frame where the old adhesive was located, not directly onto the battery itself.

Press the new battery firmly into place to secure it.