There are basically two options for shipping damaged lithium batteries. Option 1 is procurement of a damaged, defective, recall shipping kit commonly known as a DDR kit and pack and ship the material yourself. These are fairly easy to use, but it is critical that you follow the packing instructions to the letter or risk punitive action from the federal government. Option 2 is to contact a dangerous good packing company and have them pack the materials for you. In this case, it will be important to confirm that they either hold a special permit from the US Department of Transportation that permits them to pack and ship damaged/defective lithium batteries or that they are using an approved DDR kit. In either case, the battery should be protected from shorting and discharged below 30% capacity in advance (if practical) to minimize the chance for a thermal event while the unit is in transit.