As Bighurt mentions, there are wires that connect to your current battery. But you will need 2 additional jumper wires to connect a second battery.
Carefully review the terminal type on your current battery. Buy another matching battery. Then buy jumpers with the connectors already attached, in the length that you need. 12" will likely do you well.
Matching battery groups and capacities is somewhat important. If possible, just get the exact same battery. Your dealer can likely sell you one as well - or any auto-parts store and evens Sams/Costco.
Best of luck.
Moving this thread to Bighorn Electrical
Jim