12v Dual Battery System

Having one portable battery for the outdoors is good, but imagine how powerful it is to have two. This is exactly the perk you get from having a 12V dual battery system. This is typically done in RVs, 4WDs, and boats-basically, outdoor rides that require a good run of both the engine and all the appliances inside it. 

Opting for this type of off-road or caravan battery setup adds extra peace of mind for every camper, especially those who like to go off-grid. A 12V dual battery setup ensures that you will never run out of power provided that you have sized both of your batteries properly depending on your load and the longevity of your stay at the campsite. 

Since a lot of adventurers are now switching to a 12V dual battery system, more battery providers are offering ways to make this easier. For example, you can get a Kings dual battery kit now, or opt for a Redarc dual battery system. Here at Outbax, we also have premium quality lithium batteries that will make the ideal secondary batteries.

Our range of power packs are all LiFePO4 batteries and therefore are considered lithium deep cycle batteries. These are definitely your best pick when it comes to runtime, particularly if you're camping in a remote location. Visit us today and choose which power pack best suits your upcoming adventures. 

What Is a 12V Dual Battery System?

A 12V dual battery system is mainly installed to provide sufficient power to both your vehicle's engine and the appliances on board it. It consists of a starter battery and a service battery which serve functions that cannot be interchanged. 

This means that your starter battery is not designed to provide a consistent stream of power to run electronics, the same way that a service or auxiliary battery is not fit for kickstarting vehicle engines. 

Take note that these batteries operate as two isolated systems. When your vehicle is running, your starter battery coordinates with your alternator to power your vehicle, while the secondary service battery powers all gears and accessories inside your ride once your vehicle turns off.

This independent function of the batteries is made possible through the isolator. An isolator works to disconnect your starter battery from your secondary power pack so you only draw power from one source at a time. It also ensures that both batteries charge properly to prevent damage or insufficient output. 

Keeping your battery isolated during operation is crucial so you do not drain your vehicle battery and prevent it from starting up. In some cases, there are 4x4 dual battery setups that have isolators allowing you to simultaneously use both batteries, boosting the starting power to your vehicle in case the main battery suddenly drops in voltage. 

What Type of Battery is Best For a 12V Dual Battery System?

There are tons of starter batteries you can choose from but when it comes to auxiliary batteries, the best choice will always be lithium batteries, specifically LiFePO4 batteries. These are 1/3 the weight of conventional lead-acid batteries, so you won't have to weigh down your vehicle that much. A 100Ah lithium battery can weigh as light as 13kgs or even less plus, can even have a slimline lithium battery version for those who have limited space inside the RV.

You win most in a LiFePO4 pack in terms of composition and performance. This battery type is a deep cycle or deep cell battery, meaning you get 80% of useable capacity instead of the usual 50% DoD. Aside from this, it can also handle a higher charge current, allowing your battery to charge faster. This is why it's considered the ideal off-grid battery as it provides ample power for an extended period of time without needing a recharge. 

Backed with a built-in battery management system (BMS), you won't have to worry about overcharging, overheating, and short circuits anymore. Safety is another top priority in a LiFePO4 battery, which is why it was designed not to explode or catch fire. This is one of the reasons why it’s highly recommended by outdoor enthusiasts, especially if you’re a first-time battery user.

The only downside of this power pack is probably the expensive price, which can still be considered a good investment given the quality and lifespan that can last for up to a decade with proper maintenance. Another thing, this would require a specific lithium battery charger as well to prevent damage and ensure an efficient charging process.

What about the size? Many RV owners opt for a 200Ah lithium battery nowadays. It packs enough power for most camping appliances, even high-current ones like air conditioners and microwave ovens. Avid travellers even pair their dual battery systems with solar panels just to make sure that they never run out of power on the road.

Is a 12V Dual Battery System Worth It?

Dual battery system installation sure has its benefits and it's definitely worth investing in for every RV or 4x4 owner. If you're constantly going on road trips, this would be perfect for your RV or 4WD 12V electrical setup. This would also be a wise idea if you're living off-grid, like in a caravan or camper trailer. Pair it with equally efficient solar panels and you can go anywhere you like for a longer period such as during vacations.

If you like going on shorter trips, you can switch up your second battery for an inverter generator or even a portable power station too. It all boils down to your camping power requirements, but for any serious traveller, you'll never go wrong with this type of setup. It can be pricey considering that you would have to buy two batteries especially if you're planning for a lithium battery, but definitely worth it for the long term.

More from Outbax

Still searching for the "best dual battery system 4x4?" Forget that and visit Outbax instead! We have an impressive collection of 12V rechargeable batteries including lithium battery 4WD and even deep cycle marine batteries! It's a haven for every outdoor lover here mainly because we focus not just on quality but on affordability as well. Our camping gear including power sources retail for significantly lower costs-in fact, you can buy double batteries here for the price of one!

We made shopping extra convenient too. Our checkout systems are easy to understand plus, we have an expert team of customer service ready to help you out with any concern. Buy your battery with a few taps on your computer whether they're batteries in Dandenong or batteries in Toowoomba. Enjoy browsing through premium outdoor equipment and have them shipped to your doorstep for FREE!