What is a Dual Battery Install?
Overlanding & Off-Roading often take you down remote roads miles away from pavement and civilization. Often times I take these trips solo since Group Runs with my the Off-Roading Groups I'm a member of don't coordinate with my schedule. There's a certain level of risk taken when you go down an un-maintained National Park "road" or logging road alone. Installing a Second Battery in your vehicle gives you several advantages over running just a single one. In this article I'll cover the pros, cons, design, and parts used for my Dual Battery Install. Click the "Read More" button to continue.
Pros & Cons
How Does It Work?
In order to connect two batteries in a vehicle there needs to be a device which connects the two and provides some sort of electrical control. The ML-ACR serves as a relay between the House and Start battery in order to ensure both batteries stay charged while the engine is turned on and the alternator is charging the batteries. When the engine is turned off and there is an electrical load on the batteries, the ML-ACR automatically isolates these batteries in order to prevent a full discharge of the Starting battery. As mentioned before the ML-ACR can also bridge the batteries in high-load electrical scenarios such as winching. This is highly useful to have to ensure your battery won't die in the middle of a recovery scenario.
Looking at this diagram you can see how the new House battery connects to the ML-ACR which in turn connects to the engine & engine alternator. Shown connected to the House battery is a power block which allows you have a single location for fused add-on circuits such as LED light bars, USB charging ports, and air compressors. The large box on the right above the engine is a switch which is included with the Blue Sea ML-ACR which allows you to remotely control the relay from the vehicle cabin.
After researching this topic for several weeks I finally pulled the trigger on the follow parts. There's some parts such as the Blue Seas ML-ACR which have multiple similar options on the market. As with anything else there are individual pros & cons but for my application I found the ML-ACR checks all the boxes. Here is the parts list:
Continue reading about the Dual Battery Install in Part 2...
On Part 2 we'll cover the actual install of these parts and how this systems comes together. Learn from my mistakes and find out what I would do different if I had to do this all over again.