While using a pair of tweezers to hold the motherboard shield out of the way, use the pointed end of a spudger to pry up the battery press connector.

Take care to pry only under the edge of the connector to prevent damaging the socket itself and surrounding components.

To re-attach press connectors like this one, carefully align and press down on one side until it clicks into place, then repeat on the other side. Do not press down on the middle. If the connector is misaligned, the pins can bend, causing permanent damage.