I havent done this on my car on any Suby for that matter. I have done it on a friends car though, we relocated it into a battery case in the trunk. We used a 150A fuse and 0 or 2 awg wire....I forgot which. If you do this be sure that you get a battery case, just incase something might happen you wouldnt be making a mess of your trunk.
you just used a 150amp fuse? perfect! i've got a 150 amp circuit breaker that I can use. yeah i'm actually going to get a different battery, forgot the model but it's an odyssey. measure something like 7" x 7" x 3", and it will fit under the passenger seat so that's where i'm planning on putting it. completely sealed battery, 250 some CCAs. i'll probably try out the circuit breaker and change accordingly if it keeps opening the circuit.
Make sure you leave a vent from the case to the outside. Even though its sealed, if it ever does start venting gas (hydrogen, BTW) by mistake, you don't want it building up. 1 spark and its no more car.