Solder the positive battery wire back to the second position solder pad.

Apply glue to cover the exposed wire and ground terminals.

Continue reassembly in reverse order.

Once assembly is complete, complete the charging process with the USB cable.

If you have it, it is recommended to monitor the charge with a USB power meter.

Note: the battery will require a few deep cycles (empty -> full) to re-stabilize after being drained for an extended period of time.