Step 1: Gather the Tools You Will Need.
Tools needed: 1x Wire Stripers, 2 Different colors of wire, Solder and Soldering Gun, Electrical Tape, 2x Crocodile Clips, A Multimeter.And of course a battery to recycle.
Step 2: Test the Battery and Weld Wires to Contacts.
Use the wire cutters to strip a few lengths of different color wire and connect crocodile clips to each wire on one end,now heat up your soldering gun/iron and carefully weld the wires to the right connections,be careful not to melt the plastic on the battery itself,melted plastic coats the metal and makes welding harder,so be quick about it.
When done,take it over the charger and see if it still works and your welding was good,if it was,just nicely cover the whole battery in duct tape,and some of the wire also so it do not pull out when you drop it etc.