I am the kind of guy who likes to run my electronics. I like to run them non-stop. When I turn the key off, I want the tunes and the lights to keep going. The party should not stop when the tires stop rolling.
Yet Teryx and Teryx4 enthusiasts know that the stock electrical system, even in the newer rigs, is pretty meager. The charging system and the primary battery leave only but a small amount of wiggle room for aftermarket accessories. The stock battery is good for starting the 783cc motor and running a phone charger. I don't trust that U1 sized battery to start the engine back up when I'm a few miles from camp down in an area that isn't real accessible.
So it came time to think about dual batteries.
I went back and forth between a few setups. I really like the Fuel UTV dual Odyssey 925 battery holder. But the specs on the 925 as an auxiliary battery were not quite up to what I had in mind. I wanted something with more AH and more reserve capacity.
My electrical load is not completely over the top: a dome lamp, 40" LED lightbar, and SSV stereo. Realistically, my current draw is about 24A when everything is turned on, and slightly closer to the 20A mark when the stereo is at more nominal volumes.
The other big electrical parasite is the Warn ProVantage 4500lb winch. A winch will pull over 250A of current at maximum load; however, the winch isn't used continuously like the lights and stereo.
I went scouring the internet looking for the best battery I could find that was still reasonable in size. I wanted to mount the battery under the driver seat. When you look for good batteries on the internet, you come across the car audio community. Those guys know batteries that needed to meet similar requirements as I did: to be sealed, to have a decent reserve capacity for extended run time without charging, and to have great, dependable power.
I decided on the XS Power brand battery. I chose the XP2000 battery which is designed to be a supplemental power source in systems. The battery is sized to be a group 24 battery and rated at 80 amp hours. When I got my hands on this battery, it is a beast. I love it. Talk about nice.
I also determined I would need a battery separator, so I chose the Sure Power 1315 dual voltage sensing smart relay. It will connect the auxiliary battery to the main battery and charging system when the main battery's voltage is at or above 13.2V. The relay will open when the main battery voltage falls below 12.8V, separating the auxiliary battery from the main battery. This ensures that the main battery stays fully charged, connects the auxiliary battery for charging but only after the stock system is satisfied. Bottom line is if all your accessories are wired to the auxiliary battery, you do not have to worry about draining your starting battery!
I took my time wiring everything up. I use my Teryx4 800 in a lot of wet and muddy conditions. I followed generally accepted marine wiring practices which includes tinned wiring and making connections up with heat, shrink adhesive lined connectors and ring terminals.
The battery separator was wired up with Kicker Hyperflex 8AWG wire. The Blue Seas fuse block was wired with 4AWG wire. The wiring to my lights and other accessories is 14AWG wire from Anchor Marine.
All in all, this was a bit bigger project than I initially though it would be. It took me several days of working 2-3 hours at a time after dinner in the evening.
Check out a few of my pics.
The wiring I used
Here is a pic of the ring terminals
Don't bust my chops too bad for using a #10 terminal on a #8 wire... lol!
This is a 50A self resetting circuit breaker
The breaker is mounted inline from the main battery to the separator.
The Sure Power 1315 separator
It is mounted under the dash panel, to the right of the glove box.
Wiring under the console
I ran the charge wire and fuse block wire under the console, protected in loom.
Blue Seas Fuse Block
This was kind of an after-thought. I wanted to be able to see the status of my new auxiliary battery. I wired this cheap waterproof digital gauge into the cubby by the driver's left knee. I'm not sure if I will leave it or not.
So there you go. It's not perfect but it works pretty good so far.