Jeep JK Dual-Battery System
Installing Genesis Offroad’s JK Dual-Battery System
When the crew at Genesis Offroad in Olive Branch, Mississippi, wanted to install a dual-battery system in their project JK, they did what any of us would and searched the Internet high and low for a kit that would meet their needs. When all they found were basic trays that didn’t include any wiring or relays or isolators, let alone instructions on how to assemble a system, they got smart and decided to make their own. What resulted is the most complete and easiest to install dual-battery system for the JK Wrangler.
Launched at Jeep Beach 2013 in Daytona, Florida, the dual-battery system is now offered for 2007-to-2013 Jeep JKs (including those with HEMI engine swaps). The new heavy-duty dual-battery box replaces the stock bulky plastic battery tray and has an integrated relay box holder that makes it quick and simple to re-install the relay box securely. Extra gussets are built into the bottom mounting bracket to stiffen the entire box, making this one of the toughest battery trays available.
The top cover plate has quite a few innovative features. All of the wiring has already been completed, and the smart isolator comes pre-installed. Welded gussets on top have holes with rubber grommets to route the wires directly to the correct battery post, so there’s no guesswork involved to make the connections. High-quality battery terminal connectors are soldered, not crimped, to the flexible 2-gauge wire connecting the batteries together.
This is an awesome system that creatively and completely adds a second battery to your JK without any major modifications. In fact, all of the factory pieces can be re-installed should you elect to ever remove the system to use on a different JK. We’re impressed with the quality of this system as well as the constructive planning behind it. If you are looking for a dual-battery system for your JK, look no further. Genesis Offroad has got you covered.
How it Works
The smart isolator provides automatic control of all the charging functions with no interaction required. When both your batteries are fully charged at 13.2 volts, they are automatically connected and are charged at the same time. When you park and turn off the engine, but continue to use accessories like lights, the stereo, or a CB, both batteries begin to drain down. When your main cranking battery reaches 12.7 volts, the smart isolator separates the batteries to ensure your cranking battery will have enough power to start the engine. The second battery continues to power your accessories for as long as it will last. After you crank the vehicle, your main cranking battery will be charged up to 13. 2 volts first, and then the isolator will begin charging your accessory battery. By only charging one battery at a time, your alternator is protected from excessive strain.
If the cranking battery is somehow drained down too low to be able to start the vehicle, simply press the Start Boost button. The isolator will connect both batteries together for one minute, acting like built-in jumper cables to jumpstart the engine using the accessory battery. As long as the combined voltage of the two batteries is at least 12.7 volts, you’ll be able to start the engine. You can also add a remote status indicator light to the dash to show when the batteries are connected and when they are both fully charged.