Use a Phillips #00 to remove the five screws securing the battery to the laptop.

Use the wide end of a spudger to push on the connector tab to slide it out of its socket.

If that doesn't work, pull the bundled cable away from the connector in the same direction as the wires are running.

Pull evenly on the full width of the cable so that no individual wires are overly strained.

Use both hands to remove the battery from the laptop.