I added a 1.5 farad capacitor and a 36aH deep cycle battery I got from Amazon to the trunk of my car. I wanted my auxiliary electronics on a completely separate and isolated switched circuit so it didn't screw with the sensitive equipment or computers in the car and I can turn it on and off at my leisure with a switch I mounted by my seat. I use it for my amp which powers some subwoofers and some extra 6x9s I put in the package tray. I also have my trailer lights and harness powered by it, and a 12v socket that is always on I can use to charge stuff when I'm away or power other things like coolers and lights and boomboxes etc.
I use an 80 amp isolator relay to charge the second circuit from the main battery as needed, but only when the switch is on. I use the same switch to control the remote input for the amp, and the lights for the sub box. An added bonus is if my main battery dies, I can jump myself off by flipping a switch, or at least charge the main battery at the rate of 80 amps. I'll add some pictures of the battery box in the trunk and the subs where you can also see the trailer wiring harness hanging from the grocery hook and the 12v socket sitting on top of the battery box. Pictures are not currently working at this time.
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I use an 80 amp isolator relay to charge the second circuit from the main battery as needed, but only when the switch is on. I use the same switch to control the remote input for the amp, and the lights for the sub box. An added bonus is if my main battery dies, I can jump myself off by flipping a switch, or at least charge the main battery at the rate of 80 amps. I'll add some pictures of the battery box in the trunk and the subs where you can also see the trailer wiring harness hanging from the grocery hook and the 12v socket sitting on top of the battery box. Pictures are not currently working at this time.
